HISTORY. Questions: 1. What diagnosis is suggested by this history? 2. How do you explain her symptoms during pregnancy?

Transcription

1 HISTORY 33-year-old woman. CHIEF COMPLAINT: months duration. Dyspnea, fatigue and nocturnal wheezing of six PRESENT ILLNESS: At ages 5 and 9, she had migratory arthritis. At age 29, in the third trimester of her second pregnancy, she had paroxysmal nocturnal dyspnea and hemoptysis. Questions: 1. What diagnosis is suggested by this history? 2. How do you explain her symptoms during pregnancy? 3-1

2 Answers: 1. The history of arthritis in childhood is consistent with acute rheumatic fever. The cardinal manifestations of acute rheumatic fever include: arthritis, carditis, chorea, subcutaneous nodules and erythema marginatum. The diagnosis of rheumatic fever may be made when these occur associated with evidence of prior group A beta hemolytic streptococcal infection. Paroxysmal nocturnal dyspnea and hemoptysis in the third trimester of pregnancy, in association with her present symptoms, are highly suggestive of pulmonary venous congestion due to rheumatic mitral valve disease. 2. Cardiac decompensation is likely to occur during the third trimester of pregnancy (especially the 28th week), the period of maximal increase in cardiac output. Proceed 3-2

3 PHYSICAL SIGNS a. GENERAL APPEARANCE - Slender young woman in no distress at rest. b. VENOUS PULSE - The CVP is estimated to be 11 cm H 2 O. JUGULAR VENOUS PULSE ECG Question: How do you interpret the venous pulse? 3-3

4 Answer: The mean CVP is elevated, reflecting an increased right atrial filling pressure. There is a giant a wave (arrow) that reflects the increased force of right atrial contraction against a stenotic tricuspid valve or a poorly compliant right ventricle. c. ARTERIAL PULSE - (BP = 120/80 mm Hg) PHONO UPPER RIGHT STERNAL EDGE S1 S2 CAROTID 1.0 SECOND Question: How do you interpret the arterial pulse? 3-4

5 Answer: The arterial pulse is normal. A normal arterial pulse in a patient with suspected rheumatic valvular heart disease severe enough to cause moderate symptoms of left heart failure, suggests a mixed valvular lesion. Isolated stenosis or regurgitation of the mitral valve (the most commonly affected by rheumatic fever) may cause a change in pulse contour. In mitral stenosis the pulse may be diminished, and in mitral regurgitation it may be enhanced. Proceed 3-5

6 d. PRECORDIAL MOVEMENTS ECG LOWER LEFT STERNAL EDGE APEX Question: How do you interpret these impulses? 3-6

7 Answer: The systolic impulses at the apex and the lower left sternal edge are sustained, consistent with hypertrophy of both ventricles. Left ventricular hypertrophy is not typical of isolated mitral stenosis (MS) and, therefore, significant mitral regurgitation (MR) and/or aortic valve disease should be suspected. Right ventricular hypertrophy suggests significant pulmonary hypertension is present. e. CARDIAC AUSCULTATION ECG PHONO UPPER RIGHT STERNAL EDGE S1 S2 Question: How do you interpret these acoustic events? 3-7

8 Answer: The first heart sound (S1) at the upper right sternal edge is increased in intensity, so that it is as loud as the normal aortic second sound (A2). S1 is normally less intense than A2 in this area. In the absence of a short P-R interval or a hyperkinetic state, this finding implies the presence of MS. e. CARDIAC AUSCULTATION (continued) UPPER LEFT STERNAL EDGE ECG 2L A 2 P 2 A 2 P sec EXPIRATION INSPIRATION Question: How do you interpret these acoustic events? 3-8

9 Answer: At the upper left sternal edge, the second heart sound (S2) splits physiologically. The pulmonic sound (P2) is louder than the normal A2, compatible with some degree of pulmonary hypertension. e. CARDIAC AUSCULTATION (continued) ECG S1 S1 A2 PHONO APEX 0.1 sec Question: How do you interpret these acoustic events? 3-9

10 Answer: An opening snap (OS) (arrow) occurs.06 sec. after A2 and is followed by a long diastolic rumble with presystolic accentuation (broken arrow) ending with a loud S1. There is a high frequency holosystolic murmur. These acoustic events identify combined MS and MR. The accentuated S1 and the OS are also typically heard at the lower left sternal edge. The OS is the acoustic equivalent of mitral valve opening and may be heard in patients with MS and a pliable valve. The interval from A2 to OS is an index of severity. The more severe the MS, the higher the left atrial pressure and the earlier the mitral valve is snapped open in diastole. Hence, the more severe the MS, the shorter the A2-OS interval. An A2-OS interval <.06 sec. usually indicates at least moderately severe stenosis. While assessment of this interval is valuable, it is affected by a variety of hemodynamic factors, and must be interpreted in the total clinical context. Proceed 3-10

11 Answer (continued): The length of the diastolic rumble is also an index of severity. With more severe stenosis, the murmur is longer, as there is a persistent gradient across the valve during more of diastole. Presystolic accentuation is due to increased turbulence at the time of atrial contraction and mitral valve closure. The intensity of the holosystolic murmur is not, per se, an index of the severity of MR. Question: Would isometric handgrip help assess this patient s auscultatory findings? 3-11

12 Answer: Yes. Her response is shown below. ECG 0.2 sec PHONO LOWER LEFT STERNAL EDGE S1 S2 OS S1 S2 OS S1 PHONO APEX CONTROL HANDGRIP Question: How do you explain the changes with the handgrip? 3-12

13 Answer: With handgrip exercise, the apical systolic murmur (arrow) and diastolic murmur (broken arrow) increase in intensity. Isometric handgrip increases peripheral resistance (ventricular afterload) and heart rate. The increased resistance increases the degree of MR and the murmur. The increased heart rate shortens diastolic filling time, raising left atrial pressure, resulting in an increase in the intensity of the diastolic rumble. Question: Would amyl nitrite help assess the patient s auscultatory findings? 3-13

14 Answer: Yes. This patient s response to amyl nitrite inhalation is shown below. 0.2 sec ECG PHONO LOWER LEFT STERNAL EDGE S1 S2 OS S1 S2 OS S1 PHONO APEX CONTROL AMYL NITRITE Question: How do you interpret these changes? 3-14

15 Answer: With amyl nitrite, the apical systolic murmur diminishes (arrow), while the diastolic murmur (broken arrow) intensifies. Amyl nitrite reduces peripheral resistance and, therefore, the MR. In addition, the reflex increase in heart rate shortens diastolic filling time, increasing left atrial pressure and, hence, the intensity of the mitral diastolic rumble. f. PULMONARY AUSCULTATION Question: How do you interpret the acoustic events in the pulmonary lung fields? Proceed 3-15

16 Answer: In the lower anterior and posterior lung fields, there are inspiratory crackles and expiratory wheezes bilaterally, reflecting chronic pulmonary congestion and bronchospasm. In all other lung fields, there are normal vesicular breath sounds. ELECTROCARDIOGRAM I II III avr avl avf V1 V2 V3 V4 V5 V6 NORMAL STANDARD Question: How do you interpret this electrocardiogram? 3-16

17 Answer: There is normal sinus rhythm with a vertical axis. The P-R interval is normal, with a deep negative P wave in V1, suggesting left atrial enlargement. These changes are consistent with rheumatic mitral valve disease. The clinically observed right ventricular hypertrophy may be less apparent electrocardiographically because it is masked by the greater left ventricular mass. Left ventricular hypertrophy that is associated with MR is also frequently not reflected in the electrocardiogram. Proceed 3-17

18 CHEST X RAYS PA LEFT LATERAL Question: How do you interpret these chest X rays? 3-18

19 Answer: The PA chest X ray shows prominence of the venous pattern in the upper lobes and a decrease in the lower lobes. This inversion of the usual pattern is typical of pulmonary venous hypertension. The cardiac silhouette is enlarged, with prominence of the pulmonary artery. Left atrial enlargement is reflected by straightening of the left heart border with a prominent left atrial appendage (arrow), a double density along the right heart border (broken arrows) and some superior displacement of the left stem bronchus. The left lateral chest X ray confirms left atrial enlargement (arrow) and shows obliteration of the retrosternal space consistent with right ventricular enlargement (broken arrow). Calcification in the area of the mitral valve is also seen (double arrow). Question: Based on the history, physical examination, electrocardiogram and chest X rays, what is your diagnosis and plan for further evaluation? 3-19

20 Answer: The history, physical examination, ECG and chest X rays are consistent with rheumatic mitral valve disease with moderately severe MS and MR associated with pulmonary hypertension. An echo Doppler study also confirmed the diagnosis. The patient was treated with salt restriction and diuretics. She remained moderately dyspneic with minimal activity. Because of her significant symptoms and the relative severity of her disease, cardiac catheterization was advised as a prelude to surgical correction. The patient refused further evaluation. After several days, the patient left the hospital against medical advice. She returned six months later complaining of the sudden onset of rapid irregular heart action, severe shortness of breath and marked weakness of her left arm and leg. An electrocardiogram was obtained immediately. Proceed 3-20

21 ELECTROCARDIOGRAM I II III avr avl avf V1 V2 V3 V4 V5 V6 V5-6 1/2 STANDARD Question: How do you interpret this ECG? 3-21

22 Answer: The ECG shows coarse atrial fibrillation with a ventricular response of approximately 90. The axis has shifted further to the right and the R/S ratio in V1 is greater, suggesting right ventricular hypertrophy. With increasing evidence of right ventricular hypertrophy, left ventricular voltage usually decreases. Therefore, the increase in voltage in leads reflecting the left ventricle (2, 3, F, V5-6 ½ standard), associated with ST-T changes, suggests left ventricular hypertrophy as well. Question: How do you explain the patient s symptoms? 3-22

23 Answer: Her symptoms are typical of atrial fibrillation causing pulmonary congestion. With the increase in heart rate, diastole is shortened, decreasing the time for left atrial emptying. In addition, without atrial contraction, the atrial contribution to ventricular filling and cardiac output is lost. The result is an increase in pulmonary venous pressure that produces pulmonary edema. Patients with rheumatic mitral valve disease frequently have left atrial thrombi. In this case, atrial fibrillation has precipitated a cerebral embolism from the left atrium to the right hemisphere causing a left hemiparesis. Question: How would you confirm this scenario in this patient? 3-23

24 Answer: Transesophageal Echocardiogram (TEE). TEE, because of its proximity to the heart, gives excellent resolution of both the left atrium and left atrial appendage. The patient s study is shown below. LA LAA Clot LAA LA Ao = Left Atrial Appendage = Left Atrium = Aorta Ao Question: How would you treat this patient? Transesophageal Echocardiogram 3-24

25 Answer: The patient was treated for pulmonary edema with oxygen and elevation of the head of the bed. She was given an intravenous beta-blocker to reduce the ventricular response to her atrial fibrillation. Furosemide was also given intravenously to reduce pulmonary congestion. Because of the risk of recurrent emboli, intravenous heparin was subsequently administered. Over the next several days, her ventricular response decreased to a normal level and her pulmonary congestion and left hemiparesis resolved. The patient was again advised that surgery was indicated, especially in view of the recent complications. She agreed, and preoperative cardiac catheterization was carried out. Proceed 3-25

26 mm Hg LABORATORY- CATHETERIZATION ADDITIONAL DATA: LV LA Pulmonary Artery Pressure = 63 / 37 (Mean = 50) 20 LV LA D LA = Left Atrium LV = Left Ventricle SHORT LONG Question: How do you interpret this pressure tracing? 3-26

27 Answer: The simultaneous left atrial and left ventricular pressure tracing shows a diastolic gradient (cross hatching) of 12 mm Hg, reflecting moderate MS. The pulmonary artery pressure is also moderately elevated. During the first short cycle, left atrial pressure exceeds left ventricular pressure throughout diastole. During the long second cycle, with more time in diastole for the left atrium to empty, left atrial and left ventricular pressures equilibrate in late diastole (D). This is the hemodynamic explanation for the variation in the mitral diastolic rumble seen in patients with MS and atrial fibrillation. A phonocardiogram demonstrating this bedside finding in this patient follows. Proceed 3-27

28 Note that during the long diastolic cycle the murmur wanes in late diastole (arrow), due to equilibration of the left atrial and left ventricular pressures. PHONO APEX S1 A2 S1 A2 ECG SHORT LONG 0.2 sec Question: What is your explanation for the lack of presystolic accentuation of the diastolic murmur (broken arrow)? 3-28

29 Answer: It is likely due to the atrial fibrillation associated with a loss of presystolic augmentation in mitral valve flow. LABORATORY (continued) ANGIOGRAMS Left Ventricular Injection - Systole LA = LEFT ATRIUM LAA = LEFT ATRIAL APPENDAGE LV = LEFT VENTRICLE PA LEFT LATERAL Question: How do you interpret these angiograms? 3-29

30 Answer: The PA film shows mitral regurgitation as dye flows from the left ventricle into an enlarged left atrium during systole. The left atrial appendage is also enlarged and straightens the left heart border, a finding that correlates with the PA chest film interpretation. Left atrial enlargement is particularly well seen on the left lateral projection. Hemodynamic study has confirmed the clinical impression of moderately severe combined mitral stenosis and regurgitation with moderate pulmonary hypertension. The patient was treated with prosthetic mitral valve replacement and was successfully cardioverted to sinus rhythm. Her postoperative course was uneventful. Proceed 3-30

31 SUMMARY Mitral stenosis is virtually always due to rheumatic heart disease. Commissural fusion and scarring of leaflet tissue often combine to produce mixed MS and MR. A prior history of rheumatic fever is found in approximately half of adult patients with rheumatic mitral valve disease. Acute rheumatic fever is the result of group A beta hemolytic streptococci reacting through an immune mechanism with certain constituents of the heart to produce inflammation. This reaction, along with subsequent scarring, fusion of the chordae and valves, and calcification results in the valvular lesions of chronic rheumatic heart disease. The mitral valve is invariably involved, with the aortic valve next in frequency. When both of these valves are affected, the tricuspid valve may also be involved. In the United States, the pulmonic valve is virtually never affected. Proceed 3-31

32 Rheumatic mitral valve disease is more frequent in women. Such patients with predominant stenosis often become symptomatic in the third trimester of pregnancy. Patients with predominant regurgitation usually become symptomatic later in life. Rheumatic mitral valve disease typically presents with insidious symptoms of fatigue and dyspnea. Subsequently, paroxysmal nocturnal dyspnea, nonproductive cough, hemoptysis and palpitations may occur. Atrial fibrillation occurs as the left atrium enlarges, and is generally associated with symptomatic deterioration, especially when there is rapid ventricular response. Thrombi commonly form in the large left atrium, and emboli to the brain, kidneys and extremities may occur. Infective endocarditis may also occur, especially if there is associated significant mitral regurgitation. Proceed 3-32

33 PATHOLOGY This specimen shows the typical chronic rheumatic lesions associated with long standing MS and MR. FIBROTIC, THICKENED ANTERIOR MITRAL LEAFLET FIBROTIC, FUSED, SHORTENED CHORDAE TENDINEAE DILATED LEFT ATRIUM FIBROTIC, THICKENED POSTERIOR MITRAL LEAFLET DILATED LEFT VENTRICLE Proceed for Case Review 3-33

34 To Review This Case of Rheumatic Heart Disease with Moderately Severe Mitral Stenosis and Regurgitation and Pulmonary Hypertension: The HISTORY is typical, with acute rheumatic fever in childhood, nocturnal dyspnea and hemoptysis during the third trimester of pregnancy, and the subsequent development of congestive failure, with atrial fibrillation precipitating pulmonary edema and a cerebral embolus. PHYSICAL EXAMINATION a. The GENERAL APPEARANCE is normal. b. The JUGULAR VENOUS PULSE mean pressure is elevated, with a giant a wave due to increased right atrial contraction into a poorly compliant, failing right ventricle. c. The CAROTID PULSE is normal as a result of the combination of MS and MR. Proceed 3-34

35 d. PRECORDIAL MOVEMENTS reveal sustained impulses at the apex and lower left sternal edge due to hypertrophy of both ventricles. e. CARDIAC AUSCULTATION at the apex reveals a loud S1, a holosystolic murmur, an OS approximately.06 sec. after A2 and a long diastolic rumble with presystolic accentuation. These findings are typical of moderately severe combined MS and MR. P2 is increased at the base, due to associated pulmonary hypertension. f. PULMONARY AUSCULTATION reveals inspiratory crackles and expiratory wheezes in the lower anterior and posterior lung fields, reflecting chronic pulmonary congestion and bronchospasm. In all other lung fields, there are normal vesicular breath sounds. The initial ELECTROCARDIOGRAM shows normal sinus rhythm, a vertical axis and left atrial enlargement. A subsequent tracing shows more advanced findings, with coarse atrial fibrillation, a shift of the axis to the right and probable right and left ventricular hypertrophy. Proceed 3-35

36 The CHEST X RAYS show pulmonary venous congestion, left atrial, pulmonary artery and right ventricular enlargement with mitral valve calcification. LABORATORY STUDIES with cardiac catheterization and angiography confirm the presence of moderately severe mitral stenosis and regurgitation associated with pulmonary hypertension. TREATMENT consists of medical therapy for congestive heart failure, and tachydysrhythmias, including rate control, cardioversion to sinus rhythm, and anticoagulants for thromboembolic disease. For severe disease, treatment consists of prosthetic mitral valve replacement. Techniques for definitive treatment of atrial fibrillation should also be considered at the time of surgery. 3-36