FUNÇÃO VENTRICULAR ESQUERDA POR ECO-3D/4D - UM NOVO PARADIGMA DE AVALIAÇÃO? LEFT VENTRICULAR FUNCTION BY 3D/4D-ECHO - A NEW PARADIGM OF ASSESSMENT?

Transcription

1 MULTIMODALIDADE DE IMAGEM NA DOENÇA CARDÍACA ISQUÉMICA MULTIPLE MODALITIES OF IMAGING IN ISCHEMIC CARDIAC DISEASE FUNÇÃO VENTRICULAR ESQUERDA POR ECO-3D/4D - UM NOVO PARADIGMA DE AVALIAÇÃO? LEFT VENTRICULAR FUNCTION BY 3D/4D-ECHO - A NEW PARADIGM OF ASSESSMENT?

2 THE HEART AND ULTRASOUND TECHNOLOGY 1941; Ultrasound human diagnosis; Karl Theo 1953; M Mode; Inge Edler & Carl Hertz 1960 s; Two-dimensional Echo; Omoto and N.Bom 1968: contrast agents in echocardiog; Gramiak and Shah 1979; Doppler; Hatle 1980; Color Doppler; Brandestini 1981; Transvenous intracardiac echo; Glassman, Kronzon 1990; Transesophageal Echo; Frazin 1992; Tridimensional Echo; Ramm et al 2000; Intracardiac echo guiding Interventions and EP 2002; Tridimensional Echo - 3D/4D 2006; Real time TE 3D

3 LV function quantification Determinants of left ventricular function Ejection fraction - Heart rate - Myocardial contractility - Haemodynamic state (Frank-Starling mechanism) Preload and afterload

4 LV function quantification How? Evaluation of left ventricular (LV) size and function - The most common reasons for performing echocardiography in the adult patient. M-Mode and 2D have poor inter- and intra-observer variability and inaccurate. M mode and 2D echocardiography make incorrect geometric assumptions about the LV. Elipsoid longitudinal - diameter Elipsoid longitudinal - area (4C) Elipsoid longitudinal - area (4C e EC) Simpson (biplane) Automated border detection Algorithms for automatic interpretation (auto-ef) * Visual estimation ( eyeball ) * Canesson et al, JACC Vol 49 nº 2, 2007

5 QUALITY ASSURANCE OF EJECTION FRACTION IN THE ECHO LAB. HOW ARE WE PERFORMING COMPARED TO GUIDELINES? N Elmayergi et al.; 2010 The most recent American Society of Echocardiography (ASE) Guidelines recommends Biplane Simpson's as the preferred method of quantitation of ejection fraction (EF) 360 studies; 2 centros (Canadá) 44% for LVF evaluation Simpson in 14,5% studies 46% with normal LVF Simpson feasibility 82,2% Original vs reanalise (Simpson) CONCLUSION: Despite the published recommendations regarding acceptable methods of ejection fraction determination, the usage of Simpson's methodology in the real world setting is highly physician dependent and generally infrequent. This is true even in situations where 2D image quality is technically feasible. Significant interobserver variation in EF determination is observed. Our findings have significant implications in every day clinical decision making and in the determination of patient prognosis. Greater physician education, quality assurance and perhaps alternative echo techniques are required to improve consistency in ejection fraction determination within echo laboratories.

6 Fracção de Ejecção é tradição (Estudos sobre IC; guidelines) Conclusion Stuart Self et al; Ultrasound 2010; 18: This study showed that the limits of agreement between four echocardiographic methods (visual estimation, wall motion scoring, biplane Simpson s method and 3D echocardiography) were unacceptable in a clinical setting. This demands accurate and reproducible assessment of LVEF in the context of absolute ejection fractions used as inclusion criteria for some interventions and therapies. In view of these findings, these methods should not be used interchangeably in the serial assessment of LVEF. Qual é a Fracção de Ejecção?

7 LV function and Echocardiography The same technology to everyone? We are in an era when so many important and often costly decisions are made. Echocardiography is able to meet the challenge.

8 Clinical case, 68 yr Previous MI CHF

9 Quantification of LV function Errors and assumptions Calculations? Why not measurements? 2D Simpson method use 2 orthogonal apical plans, the geometric assumption of LV ellipsoid shape and based on tracing boundaries Volumetric measurements using 3-dimensional echocardiography (3DE) avoid the need for geometric assumptions and the risk of underestimating volumes in foreshortened views Consequently, the evaluation of left ventricular (LV) volumes and the ejection fraction (EF) has been shown to be more reproducible and accurate with 3DE than both 2-dimensional and M-mode based techniques

10 What changed: 3D Echocardiography in 2011 Improve image quality from dedicated 3D probes Move to single probe solution - equivalent image quality to standard 2D probes and 3D imaging with same probe - allow improved bi-plane and tri-plane image quality Move to Transesophageal solutions Single beat (full volume) now available - Larger volume data sets in a single beat - Less stitch and problems with arrhythmia Software analysis greatly simplified Recent advances in computer processing and transducer construction techniques have meant that real time transthoracic 3D echocardiography is now available from major ultrasound system manufacturers.

11 3D ECHOCARDIOGRAPHY The real world 69,7% 30,3% 33 Echo Labs

12 3DQ Adv Technical factors affecting assessment: - Manual editing - Software sensitivity for Automated Border Detection - Image quality

13 Pros: - No LV foreshortening - No geometric assumption about LV shape - Semi-automatic tracking - Accurate - Reproducible Cons: - Multiple heart beat acquisition - Off-line process - Frame rate - Feasibility/quality of image - Time consuming - Costs

14 Real-Time 3-Dimensional Echocardiographic Quantification of Left Ventricular Volumes Multicenter Study for Validation With Magnetic Resonance Imaging and Investigation of Sources of Error Mor-Avi V et al; JACC Imaging, D Quantification of LV function Reproducibility of LV volumes and ejection fraction

15 Real-Time 3-Dimensional Echocardiographic Quantification of Left Ventricular Volumes Multicenter Study for Validation With Magnetic Resonance Imaging and Investigation of Sources of Error Mor-Avi V et al; JACC Imaging, 2008 Accuracy of volumes by tracing modality Spatial resolution Trabeculae interface Basal LV slices show images of a water-filled balloon with the boundaries traced in 3 different ways

16 Contrast RT3D Good image is a prerequisite for accurate quantification of LV volumes using semi-automated border detection; Left heart contrast administration has been used to enhance border detection in pts with poor endocardial visibility Cosyns B, Cardiovascular Ultrasound 2009, 7:27 Montant P, Circ Cardiovasc Imaging Jul 1;3(4):415-23

17 Transesophageal RT3D Echo Intra-operative patients ICU patients (usually ventilated) Quality image generally good (but can be a challenge) Important to accurately guiding therapy in difficult patients Benefit and advantages? LV volumes Ejection fraction Cardiac output

18 Single beat acquisition (the true real time for LV evaluation 4D) Rapid LV quantification LVA

19 Single beat acquisition (the true real time for LV evaluation 4D) LV segments Regional LV function Quality of image

20 Single versus multi-beat acquisition Lower spacial resolution Lower frame rate (25 ±4 vps) No breath-hold Irregular rhythm (A.Fib) Instantaneous acquisition True real time Higher spacial resolution Superior frame rate (52 ±16 vps) Breath-hold Regular rhythm 4x acquisition time

21 Single-Beat Versus Multibeat Real-Time 3D Echocardiography for Assessing Left Ventricular Volumes and Ejection Fraction A Comparison Study With Cardiac Magnetic Resonance Macron L; Circ Cardiovasc Imaging. 2010;3: Compared with conventional multibeat acquisitions, the 2-beat modality provides similar accuracy in LV volumes and EF measurements and should be preferred due to fewer stitching artifacts. The temporal resolution of single-beat imaging appears insufficient to capture end-diastolic and endsystolic volumes. Bland-Altman analysis for LVEF assessment by RT3DE using 1, 2, and 4 cardiac cycles. Agreement with CMR is expressed as mean difference SD.

22 Besides ejection fraction! Segmentar evaluation - Dissynchrony The change in the spiral pattern of the myocardium by remodeling, regional myocardial dysfunction or asynchronous electric conduction, may change its efficiency in terms of ejection and filling.

23 Besides ejection fraction! (SDI) Sistolic Dyssynchrony Index Timing and excursion (SDI) Sistolic Dyssynchrony index RR normalized for LV segments (time contraction minimum volume in each segment; SDI is the SD of these timings, expressed as a % of cardic cycle duration)

24 Assinchrony evaluation Real-Time 3D Echo in patient selection for cardiac resynchronization therapy Kapetanakis S; JACC Cardiov Imaging, Jan 2011 Inter-Hospital agreement for 3D Echo 187 pts (62 cases shared) 2 Hospitals (London; Hong Kong) LV Vol; LVEF and SDI

25 At baseline: QRS duration was not significantly different between patients R and NR The optimal SDI predicting response was 10,4% (sensitivity 90%; specificity 67%) Response criteria: Improvement functional class NYHA Increase EF 20% Decrease LVESV 15% Increase EF 10% Kapetanakis S; JACC Cardiov Imaging, Jan 2011

26 3D Echo provides more accurate volumetric information than conventional 2D Echo in patients whose LV quantification is critical for management; New generation 3D Echo equipments have semi-automated contour detection programs with limited operators interaction; For volume quantification, operators needs to know how to do it and its limitations; These novel algorithms compete in accuracy with CMR, but only 3D Echo can be used in every patient at his bedside. 3D Echo is a good tool to evaluate global and regional (dissynchrony) function in CRT patients