asynchronous wall motion and impairs ventricular relaxation.

Size: px
Start display at page:

Download "asynchronous wall motion and impairs ventricular relaxation."

Transcription

1 Increased afterload intensifies asynchronous wall motion and impairs ventricular relaxation TOSHIRO MIURA, VALMIK BHARGAVA, BRIAN D. GUTH, KATHARINA STIBRANT SUNNERHAGEN, SHUNICHI MIYAZAKI, CIRO INDOLFI, AND KIRK L. PETERSON University of California, San Diego, and Veterans Affairs Medical Center, San Diego, California MIURA, TOSHIRO, VALMIK BHARGAVA, BRIAN D. GUTH, KATHARINA STIBRANT SUNNERHAGEN, SHUNICHI MIYAZAKI, CIRO INDOLFI,AND KIRK L. P~~~~~~~Jncreasedafterload intensifies asynchronous wall motion and impairs ventricular relaxation. J. Appl. Physiol. 75(l): , To clarify whether impaired left ventricular relaxation elicited by increased afterload is attributable to regional dyssynchrony, we analyzed in dogs simultaneous left ventricular contrast ventriculography and pressure before and during angiotensin II infusion. Regional shortening was measured by a centerline method and a video-intensity method that served to define asynchronous motion. During angiotensin II, peak left ventricular pressure increased 35 ~fr 6 mmhg, and the isovolumic pressure time constant (7) was prolonged from 32.7 k 4.1 to 39.2 t 7.6 ms (P < 0.01). During increased afterload, early diastolic asynchrony, confined to the apical (5 of 7) and inferior regions (2 of 7), was detected in all dogs. Early systolic asynchrony was detected in the apical (5 of 7) and inferior (1 of 7) regions in six dogs. At control, systolic excursion was lower in the anteroapical than in the anterobasal region (P < 0.05). During angiotensin II, excursion of all regions was reduced, with the apical region lower than other regions (P < 0.01). In the normal dog heart, impaired relaxation with augmented afterload is coincident with asynchronous wall motion, especially in the apicalinferior region. Temporal dispersion of regional contraction may explain delayed left ventricular relaxation associated with increased afterload. ventricular afterload; myocardial relaxation; regional asynchrony LEFT VENTRICULAR RELAXATION in the normal heart can be influenced by several factors, including loading conditions, asynchrony, and deactivation (8, 13, 30, 34). Since Karliner et al. (20) first reported an impairment of ventricular relaxation after increasing aortic pressure, afterload has been considered an independent factor influencing left ventricular relaxation (1, 2, 7, 8, 10, 12, 15, 19-21). On the other hand, asynchronous wall motion of the left ventricle has been considered a further determinant of isovolumic relaxation rate (5,8,10,15,18,25,27). Lew and LeWinter (24) also demonstrated that asynchrony induced by the intracoronary injection of isoproterenol impaired early diastolic relaxation; later, volume loading was also shown to impair isovolumic relaxation (15). Moreover, it has also been documented that asynchronous wall motion affects left ventricular pressure fall in ischemic heart disease (23), during ventri- cular pacing (18), or with altered loading conditions (24, 27). We hypothesized that increased afterload itself impairs early diastolic relaxation by inducing asynchrony somewhere in the left ventricle, even in the normal heart. To test this hypothesis, contrast ventriculograms, along with hemodynamic measurements including isovolumic pressure decay, were obtained in closed-chest dogs before and after angiotensin II infusion. Ventricular wall motion was analyzed in detail by both a geometric method (32) and a video-intensity method that does not necessitate manual tracing of the chamber silhouette and provides an objective assessment in terms of location and timing of asynchronous wall motion (3, 4). METHODS Seven mongrel dogs (22-35 kg) were anesthetized with sodium thiamylal (25 mg/kg iv) and intubated; respiration and anesthesia were maintained using a mixture of 1.0% oxygen and 1.5% isofluorane via an endotracheal tube and ventilated by a respirator. Blood gases were examined and maintained within normal range throughout the experiment. Rectal temperature was monitored using an electrical thermometer and maintained at ~37 C with a heating pad under the dog. From the right carotid artery a catheter-tip micromanometer (7F Millar) was inserted retrograde into the left ventricle. The micromanometer was immersed in the 37OC water bath for 230 min before insertion to reduce baseline drift and then was calibrated with use of a mercury manometer. The pressure of the micromanometer was matched to the fluid-filled pressure transducer (Statham P23 Db) measured via the lumen of the Millar catheter. Zero pressure level was defined at the level of the right atrium. A polyethylene catheter (2.5 mm ID) with multiple side holes was inserted from the jugular vein to the superior vena cava for contrast injection. Another polyethylene catheter (0.5 mm ID) was inserted from a contralateral jugular vein to the right ventricle for pressure measurement. A femoral vein was used for fluid replacement and drug infusion. Experimental Protocol Left ventriculography was performed at baseline and after angiotensin II infusion ( pglmin). Angiotensin II increased peak left ventricular pressure by $2.00 Copyright the American Physiological Society 389

2 l 390 AFTERLOAD, VENTRICULAR RELAXATION, AND ASYNCHRONY mmhg. Hemodynamic data were recorded simultaneously on an eight-channel Brush-Gould recorder and on a Hewlett-Packard O.&in. FM tape recorder for subsequent playback, digitization, and analysis. Left Ventriculography The ventilator was stopped at end expiration, and nonionic contrast medium (Omnipaque 350) was injected into the superior vena cava at a rate of 15 ml/s for 2 s using a power injector. Continuous fluoroscopic images were obtained with a g-in. cesium iodide image intensifier (Fluoricon 300, General Electric) and television camera (Plumbicon) in a lateral projection. The radiographic technique was manually selected between KVP and 2-3 ma and held constant throughout the injection. The analog images were recorded on a high-performance video cassette recorder (VO 5800, 0.75 in., Sony) at 30 frames/s. During acquisition of the image we confirmed the absence of spontaneous respiratory motion. At least 20 min were allowed for the hemodynamic conditions to recover from the influence of previous ventriculography, and then angiotensin II ( pg/min) was infused with a Harvard infusion pump to increase peak left ventricular pressure by mmhg above control level. After a steady state was achieved, ventriculography was again performed. The order of ventriculography for pre- and post-angiotensin II infusion was random to minimize the potential influence of previous ventriculography on regional wall motion. In three dogs the left ventriculogram with angiotensin II infusion was obtained first and the control ventriculogram was acquired later. In those dogs in which angiotensin II was first infused, sufficient time was allowed for hemody- namics to recover to baseline levels before the control ventriculogram was acquired. Analysis of the Hemodynamic Data The data on FM tape were played back and digitized at 333 Hz. Ten to 15 consecutive beats were averaged using a PDP 11/03 computer system. The following variables were estimated from the averaged beat: I) left ventricular peak systolic, end-systolic, and end-diastolic pressures [end-systolic pressure defined as that occurring 20 ms before minimal left ventricular rate of pressure development (-dpldt)]; 2) left ventricular peak maximum rate of pressure development (+dp/dt) and -dp/dt; 3) right ventricular peak systolic and end-diastolic pressures, 4) heart rate, and 5) time constant of isovolumic left ventricular pressure fall (7). Left ventricular dp/dt was obtained by digitally differentiating left ventricular high-fidelity pressure. 7 was estimated as the inverse of the slope of the linear regression of the log (left ventricular pressure) vs, time during the isovolumic relaxation, i,e., from peak -dp/dt to 5 mmhg above the end-diastolic pressure (32). This model for estimation of 7 has been demonstrated to be useful for comparing the effects of interventions in a given subject (34). Image Digitization The fluoroscopic images were recorded on video tape and digitized in real time (30 frames/s) at a resolution of 512 X 512 pixels X 256 shades of gray using an image R4 Ai Excursion for Region i = v 1 Total Length FIG. 1. Schematic illustration of two-frame analysis using a modified centerline method. Li, centerline length of region (R) i (i = l-6). Ai, area of region i (i = 1-6). Total length, length of diastolic perimeter excluding valve plane. processing system (DeAnza IP8500, Gould) interfaced to a VAX 11/750 computer. During digitization of the images, care was taken to prevent any over- and underflow of video intensities. A sinus beat with homogeneous left ventricular opacification was used for analysis. We excluded premature or postextrasystolic beats from analysis. To improve the temporal resolution from 30 to 60 images/s, interlaced fields of each video frame were separated. This lowered the resolution from 512 X 512 to 512 X 256. Pixel replication was then used to obtain 512 X 512 resolution for image processing and display. Regional Wall Motion Analysis Two-frame analysis. An algorithm similar to the centerline method (32) was used to analyze regional wall motion from end-diastolic and end-systolic images. The end-diastolic frame was defined as the image with the maximum projected left ventricular area and the endsystolic frame -as the smallest projected ventricular area. Left ventricular end-diastolic and end-systolic contours were manually traced using a trackball and saved as a region of interest. Both end-diastolic and end-systolic regions of interest were displayed and overlaid with no correction for translation or rotation. The centerline between the end-diastolic and end-systolic contours was manually c lreated. The left ventricular perimeter wa.s divided i nto six regions, and th.e mean excu.rsion for each region was ca lculated as the ratio 0 f the area for that re$on divided by the length of the centerline for that region (Fig. 1). The normalized mean excursion (NMEX) for each region was estimated by dividing the mean excursion by the whole perimeter of the end-diastolic left ventricular silhouette to compensate for differences of heart size between dogs. Regional NMEX for each of the regions at control was Rci and after angiotensin II infusion was Rai for the ith region. Comparisons were made between Rci and Rcj as well as between Rai and Raj (where i,j equals 1, 2,... 6, and i does not equal j) for the six regions. Comparisons were also made between Rci and Rai, and the difference between them was defined as Ai. Video- intensity method. The video-intensity method for describing regional asynchrony ( S 1.ope method) was developed and used previously in o ur laboratory (3, 4).

3 AFTERLOAD, VEN TRICULAR RELAXATION, AND ASYNCHRONY 391 Fields (time) Slope Image coefficient = r Average Intensity (whole LV region) 4 Fields (time) Correlation Coefficient Image FIG. 2. Schematic illustration of video-intensity method (slope method): time-intensity curve of a pixel (top left); global time-intensity curve from end diastole to end diastole (temporal resolution, 16.7 ms; top right); method of calculating slope and corresponding correlation coefficient (r; middle). Sets of 4 consecutive points from a pixel and global region of interest were correlated, and slope and r were calculated. Slope and r of a given pixel were mapped, and a functional image of slope (bottom left) and r (bottom right) was created every 16.7 ms. LV, left ventricular. This method has been shown to be more sensitive in detecting regional wall motion abnormalities associated with ischemic heart disease than pixel-by-pixel temporal Fourier phase and amplitude analysis (6). A region of interest is created around the end-diastolic ventricular silhouette excluding the mitral valve and aortic valve plane. This region of interest includes the ventricular silhouette in all frames. The average time-intensity curve of the region of interest is computed for the entire cardiac cycle (Fig. 2). For any pixel location within the region of interest, its time-intensity curve is plotted. For four consecutive fields (50 ms), or data points, the video intensity of this pixel location is correlated with the corresponding intensity of the global region (independent variable) by use of linear regression analysis to yield values for slope and correlation coefficients (Fig. 2). The slope value (from to +5.12) and correlation coefficient (from -1 to +I) are then mapped as shades of gray between 0 and 255. This analysis is repeated for every pixel within the region of interest to create two parametric (functional) images, slope and correlation coefficient. These functional images are created for the whole cardiac cycle by including one new image and dropping the earliest, overlapping the previous interval by 33.3 ms. When the directional changes in regional volume of the left ventricle are similar to that of the whole left ventricle (defined as synchronous ), then the slope value of the regression of regional and global intensity changes over a given period is greater than one (3, 4). When the directional changes in regional volume of the left ventricle are opposite to that of the whole left ventricle, or the extent of regional volume change is disproportionally small (defined as asynchronous ), then the slope values are less than one. To describe the location of asynchrony, the ventricle was divided into five anatomic regions, i.e., anterobasal, anterior, apical, inferior, and inferobasal (Fig. 3). The duration of asynchrony (4) was computed as: 4 = (f - 1) + 50 ms, where f is the number of consecutive images in which the same region showed asynchrony. It is apparent from the definition of the slope that small or absent changes in global intensity (independent variable) can lead to an erroneous estimate of the slope. We therefore excluded the isovolumic phases of the cardiac cycle, as well as diastasis, from the analysis. The late diastolic phase was also not evaluated. The center of the left ventricle was excluded from quantitation because the changes in intensity in this area are small because of saturation (3). The area of asynchrony was expressed as a percentage of the analyzed shell area (Fig. 3). Global ejection fraction. Ejection fraction was calculated using the area-length method (11) and was used as an index of global left ventricular function. Statistics Hemodynamic data and changes in the NMEX before and after angiotensin II infusion were compared using the paired t test. Differences between the normal and abnormal slope values, as measured by the video-intensity method, were compared by unpaired t test. Comparison of regional differences in NMEX both at control (Rci vs. Rcj) and after angiotensin II infusion (Rai vs. Raj) was made using analysis of variance (ANOVA) for repeated measures, and each comparison was performed by Tukey s multiple comparison test (35). Regional differences in NMEX between control and after angiotensin II infusion, Ai, were again assessed using ANOVA for repeated measures. P < 0.05 was considered significant. All results are given as means t SD. RESULTS Hemodynamics The hemodynamic data at control and after angiotensin II infusion are presented in Table 1. After angiotensin II infusion, the average peak left ventricular pressure Abnormal region (number of pixels in abnormal area).,oo Abnormal Area (%) = - (number of pixels in true shell) FIG. 3. Location of abnormal regions detected by slope method was categorized as 5 anatomic regions. Analyzed region (shaded) was calculated as percentage of total shell area (see text).

4 392 AFTERLOAD, VENTRICULAR RELAXATION, AND ASYNCHRONY TABLE 1. Hemodynamic parameters before and after angiotensin II infusion,h loo la T - Control Angiotensin II HR, beatslmin PLVP, mmhg ESP, mmhg EDP, mmhg +dpldt, mmhg/s -dpldt, mmhg/s 7, ms PRVP, mmhg EDRVP, mmhg EF, % 117.4k t k t t k k t k k t *14.8* 126.5t t3.6* 179Ok Ok t7.6* t t10.2 Values are means t SD of 7 dogs. HR, heart rate; PLVP, peak left ventricular pressure; ESP, end-systolic left ventricular pressure; EDP, left ventricular end-diastolic pressure; +dpldt and -dpldt, maximum and minimal rates of left ventricular pressure development, respectively; f, time constant of isovolumic relaxation of left ventricle; PRVP, peak right ventricular pressure; EDRVP, end-diastolic right ventricular pressure; EF, left ventricular ejection fraction calculated by ventriculography. * P ( 0.01 vs. control. increased by 35 mmhg above control (P < O.OOOl), endsystolic pressure increased by 29 mmhg (P < O.OOl), and left ventricular end-diastolic pressure increased by 3.7 mmhg (P < 0.005). Heart rate, peak +dpldt and -dp/dt, and peak systolic and end-diastolic right ventricular pressures showed no significant changes. 7 increased after angiotensin II infusion from 32.7 t 4.1 to 39,2 t 7.6 ms (P c 0.005). Ejection fraction decreased after angiotensin II infusion from 45.6 t 12.7 to 32.6 t 10.2% (P < 0.001). Ventricular Wall Motion Analysis Two-frame analysis. NMEX data for each of six regions (means t SD for all seven dogs), area + length + total length, before and after angiotensin II, are presented in Fig. 4. During the control state, NMEX in the antero,apical region (Rc3) was significantly smaller than that in the anterobasal region (Rcl) (P c 0.05). All regions showed a significant reduction in NMEX after angiotensin II infusion (P < 0.01 for all regions). After angiotensin II infusion, NMEX showed difference between Ral and Ra3 (P < O.Ol), Ral and Ra4 (P < O.Ol), Ra2 and Ra3 (P < O.Ol), and Ra3 and Ra5 (P < 0.05). The excursion before and after angiotensin II (Ai) and Ai as a percentage of Rci in each region were compared and showed no significant regional differences (Fig. 5, A and B) I 1 1 L 0 I I I I I 1 1 Rl R2 R3 R4 R5 R6 FIG. 5. A: percentage change in wall NMEX after angiotensin II. No statistically significant differences between regions were observed. B: difference in wall NMEX before and after angiotensin II infusion. No statistically significant difference between regions was noted. Video-intensity method (slope method). Figure 6 shows the slope functional image before and after angiotensin II during early systole (end diastole through the following 150 ms) and early diastole (end systole through the following 150 ms). Early systole is defined as the phase of the cardiac cycle when the video intensity initially increases after a minimum value; early diastole is defined as the segment first reducing in intensity after the peak. In the control state, the entire ventricle showed slopes >l, i.e., indicating normal motion, both in early systole and early diastole (Table 2, Fig. 7). The average slope of the anterior region during early systole (1.70 t 0.43) was smaller than that in the inferior region (2.49 t 0.28, P < 0.01). At control in early diastole, no statistical differences in slope between anterior and inferior regions were observed. After angiotensin II infusion, six of seven dogs showed asynchrony in early systole and all seven in early diastole. Asynchrony was most frequently observed in the apical region in both systole and diastole (Table 2). In early systole, five dogs showed asynchrony in the apical region and one in the inferoapical region. In early diastole, five of seven dogs showed abnormality in the apical, one in the inferior, and one in the inferobasal region. The average slopes of the asynchronous regions ranged from -3.0 to 0.76 (-0.32 t 1.39) in early systole and from to 0.64 (-0.73 t 1.17) in early diastole (Table 2, Fig. 6). The average asynchronous area as a percentage of the shell area was t 9.23% during early systole and t 6.41% during early diastole. The average Q in systole was 86.1 t 16.3 ms and in diastole 81.0 t 18.4 ms. Postmortem Examination Postmortem examination demonstrated macroscopitally no scar or abnormal myocardial muscle. RI R2 R3 84 R5 R6 FIG. 4. Regional function analyzed by two-frame analysis before (0) and after angiotensin II infusion (a). Wall normalized mean excursion (NMEX), area + length + total length; Rl-R6, regions shown in Fig. 1. * P < 0,01 vs. control; t P < 0.05 vs. control; tt P < 0.05 vs. ang-iotensin II. DISCUSSION The time constant of isovolumic left ventricular pressure decay (7) may be controlled by inactivation, loading conditions, nonuniformity, or a combination of these factors (8). The load dependence of myocardial relax-

5 AFTERLOAD, VENTRICULAR RELAXATION, AND ASYNCHRONY 393 L:C:C3:CLC:ZEI:CfIEST w FIG. 6. A: functional images of slope method before angiotensin II infusion. Bottom left: during early systole; bottom right: during early diastole. Top curues show corresponding time-intensity curves from end diastole to end diastole. Red arrows depict phase of cardiac cycle analyzed. Pseudocolor lookup table bottom: negative slopes are coded in purple, blue, dark green, and green; positive slopes are coded in yellow and various hues of red and white. B: functional images of slope method after angiotensin II. Bottom left: during early systole; bottom right: during early diastole. Note that inferior-apical segment exhibits reduced negative slopes (coded in green, blue, and purple) in both early systole and diastole. Note also reduced slopes in anterior segment, depicted by narrowing of red pixel area.

6 394 AFTER LOAD, VENTRICULAR RELAXATION, AND ASYNCHRONY TABLE 2. Abnormalities after angiotensin II infusion detected by slope method Slope Dog Area of Duration, No. NOR ABNL ABNL ms Location Early systole C c c c D C Mean SD - to.51 Al.39 k Early diastole C C C C E D C Mean SD to.49 t1.17 k6.41 t18.35 NOR, normal region; ABNL, abnormal region; Area of ABNL, abnormal area as percentage of diastolic silhouette area; Duration, duration of asynchronous wall motion. Location, region of abnormality: C, apical; D, inferoapical; E, inferobasal. ation has been shown in various models, e.g., isolated muscle preparation (7, 16), isolated canine heart (2, 19), anesthetized or conscious intact canine heart (18,20,34), and normal human hearts (21). Recently, Hori et al. (19) further emphasized that the time course of loading conditions during contraction substantially influences isovolumic relaxation. The underlying mechanism of loaddependent relaxation is still unknown, but altered calcium reuptake by the sarcoplasmic reticulum may contribute to this phenomenon (1). In this series of experiments, we have demonstrated that during augmentation of afterload with angiotensin II 1) the time constant of isovolumic left ventricular pressure decay (7) was prolonged, 2) regional function assessed by systolic NMEX was uniformly reduced in all regions, and 3) in contrast to the two-frame analysis, i.e., end diastole and end systole, sequential frame-by-frame analysis of regional wall motion by a video-intensity method revealed temporal discordance of left ventricular wall motion both in early systole and early diastole, most frequently around the left ventricular apical region. These observations are in accord with the studies cited above but in addition point to an interdependence of increased afterload and nonuniformity of contraction in their effect on delayed relaxation in the intact heart. Our data suggest that impaired relaxation during an increase in afterload may be caused, at least in part, by asynchrony between various segments of the left ventricle (e.g., basal and apical regions). The systolic-diastolic geometry of the left ventricle is related to myocardial stress distribution, and regional wall motion can be influenced by regional stress changes (37). Previous angiographic observations by Rushmer (31) showed substantial deformation of the left ventricle during the isovolumic contraction phase. During the ejection phase of a normally depolarized beat at rest and under normal loading conditions, symmetrical contraction of the left ventricle has been observed, consistent with a matching of regional wall stress and regional contractility in all wall segments (26). In the animals studied here, an increase in afterload was accompanied by uniformly decreased excursion from end diastole to end systole (Fig. 5), but asynchrony was also detected during early systole and early diastole, especially in the apical region. This latter region has a relatively thin wall and the least radius of curvature, and the fibers are less circumferentially oriented than those of other regions (33). Under normal loading conditions, the stress distribution may be uniform in this region; however, with increased afterload, stress distribution becomes nonuniform, giv- ing rise to asynchronous contraction. In similar fashion, LeWinter et al. (26) studied regional differences of midwall shortening of the left ventricle at the basal, mid, and apical regions, using segment length crystals in normal dog hearts. They noted a significant disparity in regional percent segment shortening as well as a nonuniform response in segment shortening to an increase in afterload. Our study extends their findings further by use of a closed-chest animal model with intact pericardium and with angiotensin II to increase afterload. Nonuniformity unrelated to an increase in afterload has been recognized as a determinant of delayed isovolumic relaxation. Gillebert and Lew (15) showed that regional changes in contractility and asynchronous wall motion induced by the local administration of isoproterenol prolonged the time constant of isovolumic pressure fall independently of afterload or preload. Heyndrickx et al. (18) used right ventricular pacing to induce nonuniformity both at rest and during exercise and showed dyssynchronous alteration in contraction and relaxation. Improvement of systolic function and diastolic properties 4 I p < 0.01 I I p < 0.01 id ~~, ii 1 p < Anterior Inferior Abnormal Normal 1 I I 1 Control Angiotensin FIG. 7. Slope values during early systole (A) and early diastole (B). Anterior, mean slope of anterior region; Inferior, mean slope of inferior region; Abnormal, averaged slope of abnormal region detected after angiotensin II infusion; Normal, averaged slope of normal region after angiotensin II infusion; Control, before angiotensin II infusion; Angiotensin, after angiotensin II infusion.

7 AFTERLOAD, VENTRICULAR RELAXATION, AND ASYNCHRONY after nitroglycerin administra tion has been shown to im- tion and the contribution of asynchrony to impaired diaprove asynchronous relaxation; conversely, with aug- stolic function. mented preload and afterload induced by isometric exercise, segmental asynchrony was exaggerated (27). Critiques and Limitations of the Present Study The potential influences of other hemodynamic variables in this experimental preparation should also be con- The video-intensity method for analyzing regional wall sidered. The induced increase in afterload by angiotensin motion on a frame-by-frame basis does not require trac- II was accompanied by an increase in the left ventricular ing of endocardial edges, and it is automated. Manual end-diastolic pressure, reflecting an increase in end- tracing of the endocardial edges may cause poor reprodiastolic fiberstretch and volume. However, the relative ducibility in the angiographic analysis of regional wall independence of relaxation from changing preload ob- motion, making it difficult to detect subtle changes over a served by Gaasch et al. (13) suggests independence of left short interval. Furthermore, no assumption of ventricuventricular dilatation and relaxation if the afterload is lar shape or reference point is needed with the video-innot altered. By contrast, Raff and Glantz (30) found that tensity method. Thus, we believe this approach is more acute volume loading was associated with a significant sensitive in identifying asynchronous regions than other slowing of relaxation (as measured by 7); moreover, multiple linear regression analysis suggested that end-diastolic pressure, in addition to mean aortic pressure, was an independent determinant of 7. In our experiments, therefore, the small increases in fiber stretch and enddiastolic stress may have had an independent influence on relaxation, but since we did not volume load the animals acutely, this effect is presumably small in magnitude. Methodological Considerations Our geometric or two-frame method to analyze wall excursion is analogous to the centerline method developed by others (32). Sheehan et al. (32) divided the ventricular perimeter between end diastole and end systole into 100 chords; this method was shown to have less inter- and intraobserver variability than other methods of analyzing the ventriculogram. However, it has been shown that chord excursion is quite sensitive to a tracing error. Thus, in the present study we used a similar algorithm to the centerline method, but the excursion was averaged for six large regions to minimize any tracing artifact. The extent of wall shortening was greater in the anterobasal than in the apical region. This pattern is quite similar to the data presented by Sheehan et al. in a study of normal humans. After angiotensin II infusion, the difference of the excursion between regions became apparent (Fig. 5), although the extent of reduction of excursion was quite uniform (Fig. 6) by two-frame analysis of end diastole and end systole. This indicates that increased afterload not only causes global reduction of left ventricular ejection but also induces nonuniformity of regional wall motion during contraction and relaxation. Our data strongly suggest that, in the analysis of the effect of increased afterload, it is important to assess the temporal concordance of the regional wall motion in addition to the extent of contraction calculated from end diastole to end systole. One might speculate whether nonuniformity of contraction might also have a role in the delayed relaxation of chronic afterload excess in humans. For example, Chen and Gibson (10) showed prolongation of the isovolumic relaxation period in hypertensive patients. Other studies also indicated impaired relaxation and ventricular filling in hypertensive patients (9, 12). None of these reports, however, examined in detail regional wall mo- existing methods because of its higher spatial and temporal resolution. Fourier phase and amplitude analysis may provide similar information (6), but its sensitivity has been shown to be less than that of the slope method (4). Hansen et al. (17), using midwall markers, showed an increase in torsional deformation after cessation of rapid atria1 pacing. This type of whole heart motion could con- ceivably contribute to the effects observed in our study. Contrast ventriculographic assessment of regional wall motion cannot be used to differentiate between rotational, torsional, or translational motion, and it cannot be used to separate early relaxation from late systolic contraction. Translation or rotation of the heart in the closed chest and intact pericardium is relatively small. Moreover, compared with the control state, increased afterload may not alter whole heart motion; rather, with increased afterload the left ventricle dilates, global sys- tolic shortening decreases, and less space becomes available in the pericardium for whole heart motion. Thus it seems unlikely that increased whole heart torsion, translation, or rotation affected our conclusions. It has been shown that angiotensin II has positive inotropic effects that are complex and modulated by converting enzyme activity (28). Therefore, an increase in afterload induced by this vasoconstrictor may also be accompanied by a change in inotropic state. However, in this protocol, peak positive dpldt was not significantly changed, and the small increase in peak positive dpldt can be explained by the increase in preload. It seems unlikely, therefore, that a hidden regional inotropic effect could have contributed to the asynchrony noted in these animals. A more plausible side effect of angiotensin II would be its potential for causing coronary vasoconstriction and regional ischemia. However, the uniform decrease in segment shortening in all regions of the left ventricle belies this interpretation. Finally, iodinated contrast medium may also influence regional wall motion, but use of nonionic contrast medium for levophase opacification and randomization of the sequence of ventriculography should have minimized this potential influence on wall synchrony. In summary, this experimental protocol in the closed- chest anesthetized dog suggests that increased afterload is associated with significant early-systolic and earlydiastolic asynchrony of left ventricular contraction. In view of other experimental observations relating nonuniformity of contraction to delayed relaxation, the infer-

8 396 AFTERLOAD, VENTRI CULAR RELAXATION, AND ASYNCHRONY ence is strong that the asynchrony secondary to increased afterload is responsible, in whole or in part, for the well-known effect of increased arterial pressure on the time constant of isovolumic pressure decline. Our data also suggest that, in the normal heart operating under normal loading conditions, regional wall stress is closely matched to regional wall thickness and curvature so as to maximize the synchronicity of left ventricular contraction and optimize the rate of isovolumic relaxation. We thank Margaret R. Hill, Denice Jio, and Farid Abdel Wahhab for technical assistance; Mark Miller for computer and electronics support; and Elizabeth Gilpin for advice in the statistical analyses. Address for reprint requests: K. L. Peterson, Dept. of Medicine (H- 20. fill), Univ. of California, San Diego, Medical Center, San Diego, CA Received 23 December 1990; accepted in final form 1 March REFERENCES 1. ALLEN, D. G., AND S. KURIHA~. Length changes during contraction affect the intracellular Ca++ of heart muscle. J. Physiol. Lond. 310: 75P-76P, ARIEL, Y., W. H. GAASCH, D. K. BOGEN, AND T. A. MCMAHON. Load-dependent relaxation with late systolic volume steps: servopump studies in the intact canine heart. Circulation 75: , BHARGAVA, V. New video-intensity based wall motion analysis technique. Conput. 1Med. Imaging Graphics 14: , BHARGAVA, V., K. S. SUNNERHAGEN, M. RASHWAN, R. A. PODO- LIN, AND R. SHABETAI. Effect of atria1 pacing on left ventricular regional wall motion using a new video intensity technique. Coronary Artery Dis. 1: 65-74, BLAUSTEIN, A. S., AND W, H. GAASCH. Myocardial relaxation. VI. Effects of beta-adrenergic tone and asynchrony on LV relaxation rate. Am. J. Physiol. 244 (Heart Circ. Physiol. 13): H417-H422, BOTVINICK, E., R. DUNN, M. FRAIS, W. O CONNELL, D. SHOSA, R. HERFKENS, AND M. SCHEINMAN. The phase image: its relationship to patterns of contraction and conduction. Circulation 65: , BRUTSAERT, D. L., N. M. DE CLERCK, M. A. GOETHALS, AND P. R. HO&MANS. Relaxation of ventricular cardiac muscle. J. Physiol. Lond. 283: , BRUTSAERT, D. L., F. E. RADEMAKERS, AND S. U. SYS. Triple control of relaxation: implications in cardiac disease. Circulation 69: ,1983. CARUANA, M., I. AL-KHAWAJA, A. LAHIRI, J. LEWIS, AND E. B. R~RY. Radionuclide measurements of diastolic function for assessing left ventricular abnormalities in the hypertensive patient. Br. Heart J. 59: , CHEN, W., AND D. GIBSON. Relation of isovolumic relaxation to left ventricular wall movement in man. Br. Heart J. 42: 51-56, DODGE, H. T., H. SANDLER, W. A. BAXLEY, AND R. R. HAWLEY. Usefulness and limitation of radiographic methods for determining left ventricular volume. Am. J. Curdiol. 18: 10-24, FOUAD, F. M., R. C. TARAZI, J. H. GALLAGHER, W. J. MACINTYRE, AND S. A. COOK. Abnormal left ventricular relaxation in hypertensive patients. Clin. Sci. Lond. 59: , GAASCH, W. H., A. S. BLAUSTEIN, C. W. ANDRIAS, R. P. DONAHUE, AND B. AVITAL. Myocardial relaxation. II. Hemodynamic determinants of rate of left ventricular isovolumic pressure decline. Am. J. Physiol. 239 (Heart Circ. Physiol. 8): Hl-H6, GAASCH, W. H., J. D. CARROLL, A. S. BLAUSTEIN, AND 0. H. L. BING. Myocardial relaxation: effects of preload on the time course of isovolumetric relaxation. Circulation 73: , GILLEBERT, T. C., AND W. Y. W. LEW. Nonuniformity and volume loading independently influence isovolumic relaxation rates. Am. J. Physiol. 257 (Heart Circ. Physiol. 26): H1927-H1935, GOETHALS, M. A., P. R. HOUSMANS, AND D. L. BRIJTSAERT. Load ing determinants of relaxation in cat papillary muscle. Am. J. Physiol. 242: ,1982. HANSEN, D. E., G. T. DAUGHTERS II, E. L. ALDERMAN, N. B. IN- GELS, AND D. C. MILLER. Torsional deformation of the left ventricle midwall in human hearts with intramyocardial markers: regional heterogeneity and sensitivity to the inotropic effects of abrupt rate changes. Circ. Res. 62: , HEYNDRICKX, G. R., P. J. VANTRIMPONT, M. F. ROUSSEAU, AND H. POULEUR. Effects of asynchrony on myocardial relaxation at rest and during exercise in conscious dogs. Am. J. Physiol. 254 (Heart Circ. Physiol. 23): H817-H822,1988. HORI, M., M. INOIJE, M. KITAKAZE, K. TSUJIOKA, Y. ISHIDA, M. FUXIJNAMI, S. NAKAJIMA, A. KITABATAKE, AND H. ABE. Loading sequence is a major determinant of afterload-dependent relaxation in intact canine heart. Am. J. Physiol. 249 (Heart Circ. Physiol. 18): H747-H754,1985. KARLINER, J. S., M. M. LEWINTER, F. MAHLER, R. ENGLER, AND R. A. O ROURKE. Pharmacologic and hemodynamic influences on the rate of isovolumic left ventricular relaxation in the normal conscious dog. J. Clin. Invest. 60: , KATAYAMA, K., T. K~MADA, M. MATSUZAKI, T. FUJII, M. KOHNO, H. OGAWA, M. OZAKI, Y. MATSUDA, AND R. KUSUKAWA. Effect of afterload on the left ventricular pressure fall during isovolumic relaxation period in man. Jpn. Circ. J. 52: , KLAUSNER, S. C., T. J. BLAIR, W. F. BULAWA, G. M. JEPPSON, R. L. JENSEN, AND P. D. CLAYTON. Quantitative analysis of segmental wall motion throughout systole and diastole in the normal human left ventricle. Circulation 65: , KUMADA, T., J. S. KARLINER, H. POULEUR, K. P. GALLAGHER, K. SHIRATO, AND J. ROSS, JR. Effects of coronary occlusion on early ventricular diastolic events in conscious dogs. Am. J. Physiol. 237 (Heart Circ. Physiol. 6): H542-H549, LEW, W. Y. W., AND M. M. LEWINTER. Regional circumferential lengthening patterns in canine left ventricle. Am. J. Physiol. 245 (Heart Circ. Physiol. 14): H741-H748, LEW, W. Y. W., AND C. M. RASMUSSEN. Influence of nonuniformity on rate of left ventricular pressure fall in the dog. Am. J. Physiol. 256 (Heart Circ. Physiol. 25): H222-H232, LEWINTER, M. M., R. S. KENT, J. M. KROENER, T. E. CAREW, AND J. W. COVELL. Regional differences in myocardial performance in the left ventricle of the dog. Circ. Res. 37: , LUDBROOK, P. A., J. D. BYRNE, AND A. J. TIEFENBRIJNN. Association of asynchronous protodiastolic segmental wall motion with impaired left ventricular relaxation. Circulation 64: , MEULEMANS, A. L., L. J. ANDRIES, AND D. L. BRIJTSAERT. Does endocardial endothelium mediate positive inotropic response to angiotensin I and angiotensin II? Circ. Res. 66: , PINTO, J. G., AND R. WIN. Non-uniform strain distribution in papillary muscles. Am. J. Physiol. 233 (Heart Circ. Physiol. 2): H410- H416,1977. RAFF, G. L., AND S. A. GLANTZ. Volume loading slows left ventricular isovolumic relaxation rate: evidence of load dependent relaxation in the intact dog heart. Circ. Res. 48: , RUSHMER, R. F. Initial phase of ventricular systole: asynchronous contraction. Am. J. Physiol. 184: , SHEEHAN, F. H., D. K. STEWART, H. T. DODGE, S. MI?TEN, E. L. BOLSON, AND B. G. BROWN. Variability in the measurement of regional left ventricular wall motion from contrast angiograms. Circulation 68: ,1983. STREETER, D. D., H. B. SPOTNITZ, D. P. PATEL, J. R. Ross, JR., AND E. H. SONNENBLICK. Fiber orientation in the canine left ventricle during diastole and systole. Circ. Res. 24: , WEISS, J., 3. W. FREDERIKSEN, AND M. L. WEISFELDT. Hemodynamic determinants of the time-course of fall in canine left ventricular pressure. J. Clin. Inuest. 58: , WINER, B. J. Statistical Principles in Experimental Design (2nd ed.). New York: McGraw-Hill, 1971, p YELLIN, E. L., M. HORI, C. YORAN, E. H. SONNENBLICK, S. GAB- BAY, AND R. W. M. FRATER. Left ventricular relaxation in the filling and nonfilling intact canine heart. Am. J. Physiol. 250 (Heart Circ. Physiol. 19): H620-H629, YIN, F. C. P. Ventricular wall stress. Circ. Res. 49: , ZILE, M. R., A. S. BLAUSTEIN, G. SHIMUZU, AND W. H. GAASCH. Right ventricular pacing reduces the rate of left ventricular relaxation and filling. J. Am. Coil. Cardiol. 10: , 1987.

Starling s Law Regulation of Myocardial Performance Intrinsic Regulation of Myocardial Performance

Starling s Law Regulation of Myocardial Performance Intrinsic Regulation of Myocardial Performance Regulation of Myocardial Performance Intrinsic Regulation of Myocardial Performance Just as the heart can initiate its own beat in the absence of any nervous or hormonal control, so also can the myocardium

More information

Section Four: Pulmonary Artery Waveform Interpretation

Section Four: Pulmonary Artery Waveform Interpretation Section Four: Pulmonary Artery Waveform Interpretation All hemodynamic pressures and waveforms are generated by pressure changes in the heart caused by myocardial contraction (systole) and relaxation/filling

More information

Note: The left and right sides of the heart must pump exactly the same volume of blood when averaged over a period of time

Note: The left and right sides of the heart must pump exactly the same volume of blood when averaged over a period of time page 1 HEART AS A PUMP A. Functional Anatomy of the Heart 1. Two pumps, arranged in series a. right heart: receives blood from the systemic circulation (via the great veins and vena cava) and pumps blood

More information

Flash, Rocking on others Added value in DCM and CRT. C. Parsai Polyclinique des Fleurs France

Flash, Rocking on others Added value in DCM and CRT. C. Parsai Polyclinique des Fleurs France Flash, Rocking on others Added value in DCM and CRT C. Parsai Polyclinique des Fleurs France Cleland JGF et al. (2007) Nat Clin Pract Cardiovasc Med 4: 90 101 Predicting CRT Response Device Related Patient

More information

RACE I Rapid Assessment by Cardiac Echo. Intensive Care Training Program Radboud University Medical Centre NIjmegen

RACE I Rapid Assessment by Cardiac Echo. Intensive Care Training Program Radboud University Medical Centre NIjmegen RACE I Rapid Assessment by Cardiac Echo Intensive Care Training Program Radboud University Medical Centre NIjmegen RACE Goal-directed study with specific questions Excludes Doppler ultrasound Perform 50

More information

Normal & Abnormal Intracardiac. Lancashire & South Cumbria Cardiac Network

Normal & Abnormal Intracardiac. Lancashire & South Cumbria Cardiac Network Normal & Abnormal Intracardiac Pressures Lancashire & South Cumbria Cardiac Network Principle Pressures recorded from catheter tip Electrical transducer - wheatstone bridge mechanical to electrical waveform

More information

Anatomi & Fysiologi 060301. The cardiovascular system (chapter 20) The circulation system transports; What the heart can do;

Anatomi & Fysiologi 060301. The cardiovascular system (chapter 20) The circulation system transports; What the heart can do; The cardiovascular system consists of; The cardiovascular system (chapter 20) Principles of Anatomy & Physiology 2009 Blood 2 separate pumps (heart) Many blood vessels with varying diameter and elasticity

More information

Normal Intracardiac Pressures. Lancashire & South Cumbria Cardiac Network

Normal Intracardiac Pressures. Lancashire & South Cumbria Cardiac Network Normal Intracardiac Pressures Lancashire & South Cumbria Cardiac Network Principle Pressures recorded from catheter tip Electrical transducer - wheatstone bridge mechanical to electrical waveform display

More information

Exchange solutes and water with cells of the body

Exchange solutes and water with cells of the body Chapter 8 Heart and Blood Vessels Three Types of Blood Vessels Transport Blood Arteries Carry blood away from the heart Transport blood under high pressure Capillaries Exchange solutes and water with cells

More information

Practical class 3 THE HEART

Practical class 3 THE HEART Practical class 3 THE HEART OBJECTIVES By the time you have completed this assignment and any necessary further reading or study you should be able to:- 1. Describe the fibrous pericardium and serous pericardium,

More information

The P Wave: Indicator of Atrial Enlargement

The P Wave: Indicator of Atrial Enlargement Marquette University e-publications@marquette Physician Assistant Studies Faculty Research and Publications Health Sciences, College of 8-12-2010 The P Wave: Indicator of Atrial Enlargement Patrick Loftis

More information

Electrocardiography I Laboratory

Electrocardiography I Laboratory Introduction The body relies on the heart to circulate blood throughout the body. The heart is responsible for pumping oxygenated blood from the lungs out to the body through the arteries and also circulating

More information

Direct Arterial Blood Pressure Monitoring Angel M. Rivera CVT, VTS (ECC) Animal Emergency Center Glendale, WI March 2003

Direct Arterial Blood Pressure Monitoring Angel M. Rivera CVT, VTS (ECC) Animal Emergency Center Glendale, WI March 2003 Direct Arterial Blood Pressure Monitoring Angel M. Rivera CVT, VTS (ECC) Animal Emergency Center Glendale, WI March 2003 Introduction Direct measurement of arterial blood pressure is obtained via a peripheral

More information

Circulatory System Review

Circulatory System Review Circulatory System Review 1. Draw a table to describe the similarities and differences between arteries and veins? Anatomy Direction of blood flow: Oxygen concentration: Arteries Thick, elastic smooth

More information

Doppler. Doppler. Doppler shift. Doppler Frequency. Doppler shift. Doppler shift. Chapter 19

Doppler. Doppler. Doppler shift. Doppler Frequency. Doppler shift. Doppler shift. Chapter 19 Doppler Doppler Chapter 19 A moving train with a trumpet player holding the same tone for a very long time travels from your left to your right. The tone changes relative the motion of you (receiver) and

More information

Clinical Training for Visage 7 Cardiac. Visage 7

Clinical Training for Visage 7 Cardiac. Visage 7 Clinical Training for Visage 7 Cardiac Visage 7 Overview Example Usage 3 Cardiac Workflow Examples 4 Remove Chest Wall 5 Edit Chest Wall Removal 6 Object Display Popup 7 Selecting Optimal Phase 8 Thick

More information

Distance Learning Program Anatomy of the Human Heart/Pig Heart Dissection Middle School/ High School

Distance Learning Program Anatomy of the Human Heart/Pig Heart Dissection Middle School/ High School Distance Learning Program Anatomy of the Human Heart/Pig Heart Dissection Middle School/ High School This guide is for middle and high school students participating in AIMS Anatomy of the Human Heart and

More information

Lecture Outline. Cardiovascular Physiology. Cardiovascular System Function. Functional Anatomy of the Heart

Lecture Outline. Cardiovascular Physiology. Cardiovascular System Function. Functional Anatomy of the Heart Lecture Outline Cardiovascular Physiology Cardiac Output Controls & Blood Pressure Cardiovascular System Function Functional components of the cardiovascular system: Heart Blood Vessels Blood General functions

More information

HeAT: A Software Assistant for the Analysis of LV Remodeling after Myocardial Infarction in 4D MR Follow-Up Studies

HeAT: A Software Assistant for the Analysis of LV Remodeling after Myocardial Infarction in 4D MR Follow-Up Studies HeAT: A Software Assistant for the Analysis of LV Remodeling after Myocardial Infarction in 4D MR Follow-Up Studies D. Säring 1, A. Stork 2, S. Juchheim 2, G. Lund 3, G. Adam 2, H. Handels 1 1 Department

More information

Introduction to Electrocardiography. The Genesis and Conduction of Cardiac Rhythm

Introduction to Electrocardiography. The Genesis and Conduction of Cardiac Rhythm Introduction to Electrocardiography Munther K. Homoud, M.D. Tufts-New England Medical Center Spring 2008 The Genesis and Conduction of Cardiac Rhythm Automaticity is the cardiac cell s ability to spontaneously

More information

Heart Failure. Myocardial Relaxation, Restoring Forces, and Early-Diastolic Load Are Independent Determinants of Left Ventricular Untwisting Rate

Heart Failure. Myocardial Relaxation, Restoring Forces, and Early-Diastolic Load Are Independent Determinants of Left Ventricular Untwisting Rate Heart Failure Myocardial Relaxation, Restoring Forces, and Early-Diastolic Load Are Independent Determinants of Left Ventricular Untwisting Rate Anders Opdahl, MD; Espen W. Remme, MSc, Dr ing; Thomas Helle-Valle,

More information

(From the Department of Physiology, College of Medicine, University of Illinois, Chicago)

(From the Department of Physiology, College of Medicine, University of Illinois, Chicago) ENERGY METABOLISM OF THE FAILING HEART BY GEORGE DECHERD, M.D., Am) MAURICE B. VISSCHER, M.D. (From the Department of Physiology, College of Medicine, University of Illinois, Chicago) (Received for publication,

More information

Vascular System The heart can be thought of 2 separate pumps from the right ventricle, blood is pumped at a low pressure to the lungs and then back

Vascular System The heart can be thought of 2 separate pumps from the right ventricle, blood is pumped at a low pressure to the lungs and then back Vascular System The heart can be thought of 2 separate pumps from the right ventricle, blood is pumped at a low pressure to the lungs and then back to the left atria from the left ventricle, blood is pumped

More information

Introduction to CV Pathophysiology. Introduction to Cardiovascular Pathophysiology

Introduction to CV Pathophysiology. Introduction to Cardiovascular Pathophysiology Introduction to CV Pathophysiology Munther K. Homoud, MD Tufts-New England Medical Center Spring 2008 Introduction to Cardiovascular Pathophysiology 1. Basic Anatomy 2. Excitation Contraction Coupling

More information

Chapter 20: The Cardiovascular System: The Heart

Chapter 20: The Cardiovascular System: The Heart Chapter 20: The Cardiovascular System: The Heart Chapter Objectives ANATOMY OF THE HEART 1. Describe the location and orientation of the heart within the thorax and mediastinal cavity. 2. Describe the

More information

Acute heart failure may be de novo or it may be a decompensation of chronic heart failure.

Acute heart failure may be de novo or it may be a decompensation of chronic heart failure. Management of Acute Left Ventricular Failure Acute left ventricular failure presents as pulmonary oedema due to increased pressure in the pulmonary capillaries. It is important to realise though that left

More information

12-Lead EKG Interpretation. Judith M. Haluka BS, RCIS, EMT-P

12-Lead EKG Interpretation. Judith M. Haluka BS, RCIS, EMT-P 12-Lead EKG Interpretation Judith M. Haluka BS, RCIS, EMT-P ECG Grid Left to Right = Time/duration Vertical measure of voltage (amplitude) Expressed in mm P-Wave Depolarization of atrial muscle Low voltage

More information

HEART HEALTH WEEK 3 SUPPLEMENT. A Beginner s Guide to Cardiovascular Disease HEART FAILURE. Relatively mild, symptoms with intense exercise

HEART HEALTH WEEK 3 SUPPLEMENT. A Beginner s Guide to Cardiovascular Disease HEART FAILURE. Relatively mild, symptoms with intense exercise WEEK 3 SUPPLEMENT HEART HEALTH A Beginner s Guide to Cardiovascular Disease HEART FAILURE Heart failure can be defined as the failing (insufficiency) of the heart as a mechanical pump due to either acute

More information

Edwards FloTrac Sensor & Edwards Vigileo Monitor. Measuring Continuous Cardiac Output with the FloTrac Sensor and Vigileo Monitor

Edwards FloTrac Sensor & Edwards Vigileo Monitor. Measuring Continuous Cardiac Output with the FloTrac Sensor and Vigileo Monitor Edwards FloTrac Sensor & Edwards Vigileo Monitor Measuring Continuous Cardiac Output with the FloTrac Sensor and Vigileo Monitor 1 Topics System Configuration Physiological Principles Pulse pressure relationship

More information

THE HEART Dr. Ali Ebneshahidi

THE HEART Dr. Ali Ebneshahidi THE HEART Dr. Ali Ebneshahidi Functions is of the heart & blood vessels 1. The heart is an essential pumping organ in the cardiovascular system where the right heart pumps deoxygenated blood (returned

More information

Resuscitation in congenital heart disease. Peter C. Laussen MBBS FCICM Department Critical Care Medicine Hospital for Sick Children Toronto

Resuscitation in congenital heart disease. Peter C. Laussen MBBS FCICM Department Critical Care Medicine Hospital for Sick Children Toronto Resuscitation in congenital heart disease Peter C. Laussen MBBS FCICM Department Critical Care Medicine Hospital for Sick Children Toronto Evolution of Congenital Heart Disease Extraordinary success: Overall

More information

123 Main St NY, New York 12345 ph: (202) 555 5555 fax: (202) 555 5555

123 Main St NY, New York 12345 ph: (202) 555 5555 fax: (202) 555 5555 Patient Name: DOE, JOHN D. Gender: M Date of Study: 4/2/2013 Date of birth: 6/28/1962 Age: 50 Medical Record #: 45869725 Ordering Physician: JANE INTERNIST, MD History: Atypical Angina, Abn ECG, High Cholesterol,

More information

The mhr model is described by 30 ordinary differential equations (ODEs): one. ion concentrations and 23 equations describing channel gating.

The mhr model is described by 30 ordinary differential equations (ODEs): one. ion concentrations and 23 equations describing channel gating. On-line Supplement: Computer Modeling Chris Clausen, PhD and Ira S. Cohen, MD, PhD Computer models of canine ventricular action potentials The mhr model is described by 30 ordinary differential equations

More information

Edwards FloTrac Sensor & Edwards Vigileo Monitor. Understanding Stroke Volume Variation and Its Clinical Application

Edwards FloTrac Sensor & Edwards Vigileo Monitor. Understanding Stroke Volume Variation and Its Clinical Application Edwards FloTrac Sensor & Edwards Vigileo Monitor Understanding Stroke Volume Variation and Its Clinical Application 1 Topics System Configuration Pulsus Paradoxes Reversed Pulsus Paradoxus What is Stroke

More information

Update on Small Animal Cardiopulmonary Resuscitation (CPR)- is anything new?

Update on Small Animal Cardiopulmonary Resuscitation (CPR)- is anything new? Update on Small Animal Cardiopulmonary Resuscitation (CPR)- is anything new? DVM, DACVA Objective: Update on the new Small animal guidelines for CPR and a discussion of the 2012 Reassessment Campaign on

More information

Heart and Vascular System Practice Questions

Heart and Vascular System Practice Questions Heart and Vascular System Practice Questions Student: 1. The pulmonary veins are unusual as veins because they are transporting. A. oxygenated blood B. de-oxygenated blood C. high fat blood D. nutrient-rich

More information

Disclosure. All the authors have no conflict of interest to disclose in this study.

Disclosure. All the authors have no conflict of interest to disclose in this study. Assessment of Left Atrial Deformation and Dyssynchrony by Three-dimensional Speckle Tracking Imaging: Comparative Studies in Healthy Subjects and Patients with Atrial Fibrillation Atsushi Mochizuki, MD*;

More information

Heart Failure EXERCISES. Ⅰ. True or false questions (mark for true question, mark for false question. If it is false, correct it.

Heart Failure EXERCISES. Ⅰ. True or false questions (mark for true question, mark for false question. If it is false, correct it. Heart Failure EXERCISES Ⅰ. True or false questions (mark for true question, mark for false question. If it is false, correct it. ) 1. Heart rate increase is a kind of economic compensation, which should

More information

HTEC 91. Topic for Today: Atrial Rhythms. NSR with PAC. Nonconducted PAC. Nonconducted PAC. Premature Atrial Contractions (PACs)

HTEC 91. Topic for Today: Atrial Rhythms. NSR with PAC. Nonconducted PAC. Nonconducted PAC. Premature Atrial Contractions (PACs) HTEC 91 Medical Office Diagnostic Tests Week 4 Topic for Today: Atrial Rhythms PACs: Premature Atrial Contractions PAT: Paroxysmal Atrial Tachycardia AF: Atrial Fibrillation Atrial Flutter Premature Atrial

More information

PSIO 603/BME 511 1 Dr. Janis Burt February 19, 2007 MRB 422; 626-6833 jburt@u.arizona.edu. MUSCLE EXCITABILITY - Ventricle

PSIO 603/BME 511 1 Dr. Janis Burt February 19, 2007 MRB 422; 626-6833 jburt@u.arizona.edu. MUSCLE EXCITABILITY - Ventricle SIO 63/BME 511 1 Dr. Janis Burt February 19, 27 MRB 422; 626-6833 MUSCLE EXCITABILITY - Ventricle READING: Boron & Boulpaep pages: 483-57 OBJECTIVES: 1. Draw a picture of the heart in vertical (frontal

More information

X X X a) perfect linear correlation b) no correlation c) positive correlation (r = 1) (r = 0) (0 < r < 1)

X X X a) perfect linear correlation b) no correlation c) positive correlation (r = 1) (r = 0) (0 < r < 1) CORRELATION AND REGRESSION / 47 CHAPTER EIGHT CORRELATION AND REGRESSION Correlation and regression are statistical methods that are commonly used in the medical literature to compare two or more variables.

More information

Electrocardiography Review and the Normal EKG Response to Exercise

Electrocardiography Review and the Normal EKG Response to Exercise Electrocardiography Review and the Normal EKG Response to Exercise Cardiac Anatomy Electrical Pathways in the Heart Which valves are the a-v valves? Closure of the a-v valves is associated with which heart

More information

Milwaukee School of Engineering Gerrits@msoe.edu. Case Study: Factors that Affect Blood Pressure Instructor Version

Milwaukee School of Engineering Gerrits@msoe.edu. Case Study: Factors that Affect Blood Pressure Instructor Version Case Study: Factors that Affect Blood Pressure Instructor Version Goal This activity (case study and its associated questions) is designed to be a student-centered learning activity relating to the factors

More information

Hemodynamic Pressure and Volume Signals

Hemodynamic Pressure and Volume Signals Hemodynamic Pressure and Volume Signals PowerLab Systems, LabChart Software and Millar Mikro-Tip and Ventri-Cath Catheters Features & Benefits n Excellent signal frequency response n No motion artifact

More information

Biol 111 Comparative & Human Anatomy Lab 9: Circulatory System of the Cat Spring 2014

Biol 111 Comparative & Human Anatomy Lab 9: Circulatory System of the Cat Spring 2014 Biol 111 Comparative & Human Anatomy Lab 9: Circulatory System of the Cat Spring 2014 Philip J. Bergmann Lab Objectives 1. To learn how blood flows through a dual circuit circulation with lungs. 2. To

More information

Functions of Blood System. Blood Cells

Functions of Blood System. Blood Cells Functions of Blood System Transport: to and from tissue cells Nutrients to cells: amino acids, glucose, vitamins, minerals, lipids (as lipoproteins). Oxygen: by red blood corpuscles (oxyhaemoglobin - 4

More information

Human Anatomy & Physiology II with Dr. Hubley

Human Anatomy & Physiology II with Dr. Hubley Human Anatomy & Physiology II with Dr. Hubley Exam #1 Name: Instructions This exam consists of 40 multiple-choice questions. Each multiple-choice question answered correctly is worth one point, and the

More information

Diagnostic and Therapeutic Procedures

Diagnostic and Therapeutic Procedures Diagnostic and Therapeutic Procedures Diagnostic and therapeutic cardiovascular s are central to the evaluation and management of patients with cardiovascular disease. Consistent with the other sections,

More information

Magnetic Resonance Quantitative Analysis. MRV MR Flow. Reliable analysis of heart and peripheral arteries in the clinical workflow

Magnetic Resonance Quantitative Analysis. MRV MR Flow. Reliable analysis of heart and peripheral arteries in the clinical workflow Magnetic Resonance Quantitative Analysis MRV MR Flow Reliable analysis of heart and peripheral arteries in the clinical workflow CAAS MRV Functional Workflow Designed for imaging specialists, CAAS MRV

More information

1 Congestive Heart Failure & its Pharmacological Management

1 Congestive Heart Failure & its Pharmacological Management Harvard-MIT Division of Health Sciences and Technology HST.151: Principles of Pharmocology Instructor: Prof. Keith Baker 1 Congestive Heart Failure & its Pharmacological Management Keith Baker, M.D., Ph.D.

More information

Systematic Approach to 12 Lead EKG Interpretation

Systematic Approach to 12 Lead EKG Interpretation Systematic Approach to 12 Lead EKG Interpretation Maureen Knechtel MPAS, PA-C Wellmont CVA Heart Institute Disclosure Statement of Financial Interest I, Maureen Knechtel, do not have a financial interest/arrangement

More information

Electrodes placed on the body s surface can detect electrical activity, APPLIED ANATOMY AND PHYSIOLOGY. Circulatory system

Electrodes placed on the body s surface can detect electrical activity, APPLIED ANATOMY AND PHYSIOLOGY. Circulatory system 4 READING AND INTERPRETING THE ELECTROCARDIOGRAM Electrodes placed on the body s surface can detect electrical activity, which occurs in the heart. The recording of these electrical events comprises an

More information

ANNE ARUNDEL MEDICAL CENTER CRITICAL CARE MEDICATION MANUAL DEPARTMENT OF NURSING AND PHARMACY. Guidelines for Use of Intravenous Isoproterenol

ANNE ARUNDEL MEDICAL CENTER CRITICAL CARE MEDICATION MANUAL DEPARTMENT OF NURSING AND PHARMACY. Guidelines for Use of Intravenous Isoproterenol ANNE ARUNDEL MEDICAL CENTER CRITICAL CARE MEDICATION MANUAL DEPARTMENT OF NURSING AND PHARMACY Guidelines for Use of Intravenous Isoproterenol Major Indications Status Asthmaticus As a last resort for

More information

Cardiovascular Physiology

Cardiovascular Physiology Cardiovascular Physiology Heart Physiology for the heart to work properly contraction and relaxation of chambers must be coordinated cardiac muscle tissue differs from smooth and skeletal muscle tissues

More information

Cardiac Arrest VF/Pulseless VT Learning Station Checklist

Cardiac Arrest VF/Pulseless VT Learning Station Checklist Cardiac Arrest VF/Pulseless VT Learning Station Checklist VF/VT 00 American Heart Association Adult Cardiac Arrest Shout for Help/Activate Emergency Response Epinephrine every - min Amiodarone Start CPR

More information

Activity 4.2.3: EKG. Introduction. Equipment. Procedure

Activity 4.2.3: EKG. Introduction. Equipment. Procedure Activity 4.2.3: EKG The following is used with permission of Vernier Software and Technology. This activity is based on the experiment Analyzing the Heart with EKG from the book Human Physiology with Vernier,

More information

ME 315 - Heat Transfer Laboratory. Experiment No. 7 ANALYSIS OF ENHANCED CONCENTRIC TUBE AND SHELL AND TUBE HEAT EXCHANGERS

ME 315 - Heat Transfer Laboratory. Experiment No. 7 ANALYSIS OF ENHANCED CONCENTRIC TUBE AND SHELL AND TUBE HEAT EXCHANGERS ME 315 - Heat Transfer Laboratory Nomenclature Experiment No. 7 ANALYSIS OF ENHANCED CONCENTRIC TUBE AND SHELL AND TUBE HEAT EXCHANGERS A heat exchange area, m 2 C max maximum specific heat rate, J/(s

More information

INTRODUCTORY GUIDE TO IDENTIFYING ECG IRREGULARITIES

INTRODUCTORY GUIDE TO IDENTIFYING ECG IRREGULARITIES INTRODUCTORY GUIDE TO IDENTIFYING ECG IRREGULARITIES NOTICE: This is an introductory guide for a user to understand basic ECG tracings and parameters. The guide will allow user to identify some of the

More information

Section Two: Arterial Pressure Monitoring

Section Two: Arterial Pressure Monitoring Section Two: Arterial Pressure Monitoring Indications An arterial line is indicated for blood pressure monitoring for the patient with any medical or surgical condition that compromises cardiac output,

More information

Measurement of Specific Heat Capacity Using Differential Scanning Calorimeter

Measurement of Specific Heat Capacity Using Differential Scanning Calorimeter INL/EXT-08-15056 Measurement of Specific Heat Capacity Using Differential Scanning Calorimeter J. E. Daw November 2008 The INL is a U.S. Department of Energy National Laboratory operated by Battelle Energy

More information

How should we treat atrial fibrillation in heart failure

How should we treat atrial fibrillation in heart failure Advances in Cardiac Arrhhythmias and Great Innovations in Cardiology Torino, 23/24 Ottobre 2015 How should we treat atrial fibrillation in heart failure Matteo Anselmino Dipartimento Scienze Mediche Città

More information

Sign up to receive ATOTW weekly email worldanaesthesia@mac.com

Sign up to receive ATOTW weekly email worldanaesthesia@mac.com INTRODUCTION TO CARDIOVASCULAR PHYSIOLOGY ANAESTHESIA TUTORIAL OF THE WEEK 125 16 TH MARCH 2009 Toby Elkington, Specialist Registrar Carl Gwinnutt, Consultant Department of Anaesthesia, Salford Royal NHS

More information

Correcting the Lateral Response Artifact in Radiochromic Film Images from Flatbed Scanners

Correcting the Lateral Response Artifact in Radiochromic Film Images from Flatbed Scanners Correcting the Lateral Response Artifact in Radiochromic Film Images from Flatbed Scanners Background The lateral response artifact (LRA) in radiochromic film images from flatbed scanners was first pointed

More information

ELECTROCARDIOGRAPHY (I) THE GENESIS OF THE ELECTROCARDIOGRAM

ELECTROCARDIOGRAPHY (I) THE GENESIS OF THE ELECTROCARDIOGRAM ELECTROCARDIOGRAPHY (I) THE GENESIS OF THE ELECTROCARDIOGRAM Scridon Alina, Șerban Răzvan Constantin 1. Definition The electrocardiogram (abbreviated ECG or EKG) represents the graphic recording of electrical

More information

Vtial sign #1: PULSE. Vital Signs: Assessment and Interpretation. Factors that influence pulse rate: Importance of Vital Signs

Vtial sign #1: PULSE. Vital Signs: Assessment and Interpretation. Factors that influence pulse rate: Importance of Vital Signs Vital Signs: Assessment and Interpretation Elma I. LeDoux, MD, FACP, FACC Associate Professor of Medicine Vtial sign #1: PULSE Reflects heart rate (resting 60-90/min) Should be strong and regular Use 2

More information

Measuring central venous pressure

Measuring central venous pressure Elaine Cole Senior lecturer ED/Trauma, City University Barts and the London NHS Trust 1 Learning outcomes That the clinician can: Describe the sites of central venous catheterisation Understand why central

More information

What is the Future of Epinephrine in Cardiac Arrest? Pros and Cons

What is the Future of Epinephrine in Cardiac Arrest? Pros and Cons What is the Future of Epinephrine in Cardiac Arrest? Pros and Cons Melissa L. Thompson Bastin, PharmD., BCPS Komal A. Pandya, PharmD., BCPS 0 Presenter Disclosure Information Melissa L. Thompson Bastin,

More information

MYOCARDIAL PERFUSION COMPUTED TOMOGRAPHY PhD course in Medical Imaging. Anne Günther Department of Radiology OUS Rikshospitalet

MYOCARDIAL PERFUSION COMPUTED TOMOGRAPHY PhD course in Medical Imaging. Anne Günther Department of Radiology OUS Rikshospitalet MYOCARDIAL PERFUSION COMPUTED TOMOGRAPHY PhD course in Medical Imaging Anne Günther Department of Radiology OUS Rikshospitalet CORONARY CT ANGIOGRAPHY (CTA) Accurate method in the assessment of possible

More information

CHAPTER 1: THE LUNGS AND RESPIRATORY SYSTEM

CHAPTER 1: THE LUNGS AND RESPIRATORY SYSTEM CHAPTER 1: THE LUNGS AND RESPIRATORY SYSTEM INTRODUCTION Lung cancer affects a life-sustaining system of the body, the respiratory system. The respiratory system is responsible for one of the essential

More information

Low-gradient severe aortic stenosis with normal LVEF: A disturbing clinical entity

Low-gradient severe aortic stenosis with normal LVEF: A disturbing clinical entity Low-gradient severe aortic stenosis with normal LVEF: A disturbing clinical entity Jean-Luc MONIN, MD, PhD Henri Mondor University Hospital Créteil, FRANCE Disclosures : None 77-year-old woman, mild dyspnea

More information

Medical management of CHF: A New Class of Medication. Al Timothy, M.D. Cardiovascular Institute of the South

Medical management of CHF: A New Class of Medication. Al Timothy, M.D. Cardiovascular Institute of the South Medical management of CHF: A New Class of Medication Al Timothy, M.D. Cardiovascular Institute of the South Disclosures Speakers Bureau for Amgen Background Chronic systolic congestive heart failure remains

More information

ACLS PHARMACOLOGY 2011 Guidelines

ACLS PHARMACOLOGY 2011 Guidelines ACLS PHARMACOLOGY 2011 Guidelines ADENOSINE Narrow complex tachycardias or wide complex tachycardias that may be supraventricular in nature. It is effective in treating 90% of the reentry arrhythmias.

More information

Traumatic Cardiac Tamponade. Shane KF Seal 19 November 2003 POS

Traumatic Cardiac Tamponade. Shane KF Seal 19 November 2003 POS Traumatic Cardiac Tamponade Shane KF Seal 19 November 2003 POS Objectives Definition Pathophysiology Diagnosis Treatment Cardiac Tamponade The decompensated phase of cardiac compression resulting from

More information

Cardiovascular System

Cardiovascular System Topics to Review Diffusion Skeletal muscle fiber (cell) anatomy Membrane potential and action potentials Action potential propagation Excitation-contraction coupling in skeletal muscle skeletal muscle

More information

BIPOLAR LIMB LEADS UNIPOLAR LIMB LEADS PRECORDIAL (UNIPOLAR) LEADS VIEW OF EACH LEAD INDICATIVE ECG CHANGES

BIPOLAR LIMB LEADS UNIPOLAR LIMB LEADS PRECORDIAL (UNIPOLAR) LEADS VIEW OF EACH LEAD INDICATIVE ECG CHANGES BIPOLAR LIMB LEADS Have both a distinctive positive and negative pole. Lead I LA (positive) RA (negative) Lead II LL (positive) RA (negative) Lead III LL (positive) LA (negative) UNIPOLAR LIMB LEADS Have

More information

Introduction to Electrophysiology. Wm. W. Barrington, MD, FACC University of Pittsburgh Medical Center

Introduction to Electrophysiology. Wm. W. Barrington, MD, FACC University of Pittsburgh Medical Center Introduction to Electrophysiology Wm. W. Barrington, MD, FACC University of Pittsburgh Medical Center Objectives Indications for EP Study How do we do the study Normal recordings Abnormal Recordings Limitations

More information

Anaesthesia and Heart Failure

Anaesthesia and Heart Failure Anaesthesia and Heart Failure Andrew Baldock, Specialist Registrar, Southampton University Hospitals NHS Trust E mail: ajbaldock@doctors.org.uk Self-assessment The following true/false questions may be

More information

II. DISTRIBUTIONS distribution normal distribution. standard scores

II. DISTRIBUTIONS distribution normal distribution. standard scores Appendix D Basic Measurement And Statistics The following information was developed by Steven Rothke, PhD, Department of Psychology, Rehabilitation Institute of Chicago (RIC) and expanded by Mary F. Schmidt,

More information

Vascular Effects of Caffeine

Vascular Effects of Caffeine Vascular Effects of Caffeine John P. Higgins MD, MBA, MPHIL, FACC, FACP, FAHA, FACSM, FASNC, FSGC Director of Exercise Physiology Memorial Hermann Sports Medicine Institute Chief of Cardiology, Lyndon

More information

Introduction Hypothesis Methods Results Conclusions Figure 11-1: Format for scientific abstract preparation

Introduction Hypothesis Methods Results Conclusions Figure 11-1: Format for scientific abstract preparation ABSTRACT AND MANUSCRIPT PREPARATION / 69 CHAPTER ELEVEN ABSTRACT AND MANUSCRIPT PREPARATION Once data analysis is complete, the natural progression of medical research is to publish the conclusions of

More information

The heart then repolarises (or refills) in time for the next stimulus and contraction.

The heart then repolarises (or refills) in time for the next stimulus and contraction. Atrial Fibrillation BRIEFLY, HOW DOES THE HEART PUMP? The heart has four chambers. The upper chambers are called atria. One chamber is called an atrium, and the lower chambers are called ventricles. In

More information

How an electronic shutter works in a CMOS camera. First, let s review how shutters work in film cameras.

How an electronic shutter works in a CMOS camera. First, let s review how shutters work in film cameras. How an electronic shutter works in a CMOS camera I have been asked many times how an electronic shutter works in a CMOS camera and how it affects the camera s performance. Here s a description of the way

More information

The Sepsis Puzzle: Identification, Monitoring and Early Goal Directed Therapy

The Sepsis Puzzle: Identification, Monitoring and Early Goal Directed Therapy The Sepsis Puzzle: Identification, Monitoring and Early Goal Directed Therapy Cindy Goodrich RN, MS, CCRN Content Description Sepsis is caused by widespread tissue injury and systemic inflammation resulting

More information

Blood Pressure. Blood Pressure (mm Hg) pressure exerted by blood against arterial walls. Blood Pressure. Blood Pressure

Blood Pressure. Blood Pressure (mm Hg) pressure exerted by blood against arterial walls. Blood Pressure. Blood Pressure Blood Pressure Blood Pressure (mm Hg) pressure exerted by blood against arterial walls Systolic pressure exerted on arteries during systole Diastolic pressure in arteries during diastole 120/80 Borderline

More information

CHAPTER XV PDL 101 HUMAN ANATOMY & PHYSIOLOGY. Ms. K. GOWRI. M.Pharm., Lecturer.

CHAPTER XV PDL 101 HUMAN ANATOMY & PHYSIOLOGY. Ms. K. GOWRI. M.Pharm., Lecturer. CHAPTER XV PDL 101 HUMAN ANATOMY & PHYSIOLOGY Ms. K. GOWRI. M.Pharm., Lecturer. Types of Muscle Tissue Classified by location, appearance, and by the type of nervous system control or innervation. Skeletal

More information

Blood vessels. transport blood throughout the body

Blood vessels. transport blood throughout the body Circulatory System Parts and Organs Blood vessels transport blood throughout the body Arteries blood vessels that carry blood AWAY from the heart Pulmonary arteries carry the deoxygenated blood from heart

More information

Clinical Observations with the Lead System

Clinical Observations with the Lead System Clinical Observations with the Lead System Frank Precordial By J. A. ABILDSKOv, M.D., W. W. STREET, M.D., N. SOLOMON, B.A., AND A. H. TOOMAJIAN, B.A. Several new lead systems for electrocardiography and

More information

Cardiovascular System & Its Diseases. Lecture #4 Heart Failure & Cardiac Arrhythmias

Cardiovascular System & Its Diseases. Lecture #4 Heart Failure & Cardiac Arrhythmias Cardiovascular System & Its Diseases Lecture #4 Heart Failure & Cardiac Arrhythmias Dr. Derek Bowie, Department of Pharmacology & Therapeutics, Room 1317, McIntyre Bldg, McGill University derek.bowie@mcgill.ca

More information

For more information about the use of the Propaq monitor, refer to the Propaq Directions For Use.

For more information about the use of the Propaq monitor, refer to the Propaq Directions For Use. Clinical Support 8500 S.W. Creekside Pl. Beaverton, OR 97008-7107 U.S.A. Telephone: 503-526-4200 Toll Free: 800-289-2500 clinicalsupport@protocol.com ELECTROCARDIOGRAPHY Introduction This article provides

More information

MECHANICAL PROPERTIES OF THE HEART AND ITS INTERACTION WITH THE VASCULAR SYSTEM. November 11, 2002

MECHANICAL PROPERTIES OF THE HEART AND ITS INTERACTION WITH THE VASCULAR SYSTEM. November 11, 2002 Cardiac Physiology Page 1 of 23 MECHANICAL PROPERTIES OF THE HEART AND ITS INTERACTION WITH THE VASCULAR SYSTEM Daniel Burkhoff MD PhD, Associate Professor of Medicine, Columbia University November 11,

More information

Cardiology. Anatomy and Physiology of the Heart.

Cardiology. Anatomy and Physiology of the Heart. Cardiology Self Learning Package Module 1: Anatomy and Physiology of the Heart. Module 1: Anatomy and Physiology of the Heart Page 1 CONTENT Introduction Page 3 How to use the ECG Self Learning package.page

More information

Pacers use a 5-letter code: first 3 letters most important

Pacers use a 5-letter code: first 3 letters most important PACEMAKERS 2 Pacemakers: Nomenclature Pacers use a 5-letter code: first 3 letters most important t First Letter: Chamber Paced A= Atrium V= Ventricle D= Dual (A+V) 2nd Letter: Chamber Sensed A= Atrium

More information

TWO-DIMENSIONAL TRANSFORMATION

TWO-DIMENSIONAL TRANSFORMATION CHAPTER 2 TWO-DIMENSIONAL TRANSFORMATION 2.1 Introduction As stated earlier, Computer Aided Design consists of three components, namely, Design (Geometric Modeling), Analysis (FEA, etc), and Visualization

More information

Hemodynamic Monitoring: Principles to Practice M. L. Cheatham, MD, FACS, FCCM

Hemodynamic Monitoring: Principles to Practice M. L. Cheatham, MD, FACS, FCCM SUMMARY HEMODYNAMIC MONITORING: FROM PRINCIPLES TO PRACTICE Michael L. Cheatham, MD, FACS, FCCM Director, Surgical Intensive Care Units Orlando Regional Medical Center Orlando, Florida Fluid-filled catheters

More information

CHAPTER THREE COMMON DESCRIPTIVE STATISTICS COMMON DESCRIPTIVE STATISTICS / 13

CHAPTER THREE COMMON DESCRIPTIVE STATISTICS COMMON DESCRIPTIVE STATISTICS / 13 COMMON DESCRIPTIVE STATISTICS / 13 CHAPTER THREE COMMON DESCRIPTIVE STATISTICS The analysis of data begins with descriptive statistics such as the mean, median, mode, range, standard deviation, variance,

More information

California Health and Safety Code, Section 1256.01

California Health and Safety Code, Section 1256.01 California Health and Safety Code, Section 1256.01 1256.01. (a) The Elective Percutaneous Coronary Intervention (PCI) Pilot Program is hereby established in the department. The purpose of the pilot program

More information

Provider Checklist-Outpatient Imaging. Checklist: Nuclear Stress Test, Thallium/Technetium/Sestamibi (CPT Code 78451-78454 78469)

Provider Checklist-Outpatient Imaging. Checklist: Nuclear Stress Test, Thallium/Technetium/Sestamibi (CPT Code 78451-78454 78469) Provider Checklist-Outpatient Imaging Checklist: Nuclear Stress Test, Thallium/Technetium/Sestamibi (CPT Code 78451-78454 78469) Medical Review Note: Per InterQual, if any of the following are present,

More information

Effect of Spinal Cord Stimulation on Myocardial Flow Reserve in Patients with Refractory Angina Pectoris

Effect of Spinal Cord Stimulation on Myocardial Flow Reserve in Patients with Refractory Angina Pectoris Effect of Spinal Cord Stimulation on Myocardial Flow Reserve in Patients with Refractory Angina Pectoris Antti Varis, Heikki Ukkonen, Antti Saraste, Tuija Vasankari, Satu Tunturi, Markku Taittonen, Pirkka

More information

Anaerobic and Aerobic Training Adaptations. Chapters 5 & 6

Anaerobic and Aerobic Training Adaptations. Chapters 5 & 6 Anaerobic and Aerobic Training Adaptations Chapters 5 & 6 Adaptations to Training Chronic exercise provides stimulus for the systems of the body to change Systems will adapt according to level, intensity,

More information

CONSTRICTIVE PERICARDITIS

CONSTRICTIVE PERICARDITIS 33 Profiles in Constrictive Pericarditis, Restrictive Cardiomyopathy, and Cardiac Tamponade Beverly H. Lorell and William Grossman BHL: Harvard Medical School, Hemodynamic and Molecular Physiology Research

More information