HISTORY. Question: What category of heart disease is suggested by the fact that a murmur was heard at birth?

Transcription

1 HISTORY 23-year-old man. CHIEF COMPLAINT: Decreasing exercise tolerance of several years duration. PRESENT ILLNESS: The patient is the product of an uncomplicated term pregnancy. A heart murmur was discovered at birth. He matured normally and had no previous limitation in physical or mental abilities. Question: What category of heart disease is suggested by the fact that a murmur was heard at birth? 20-1

2 Answer: Outflow tract obstruction (aortic or pulmonary), as shunt lesions require time for pulmonary resistance to fall after birth before shunting begins and the associated murmur is heard. PHYSICAL SIGNS a. GENERAL APPEARANCE - Normal 23-year-old man. b. VENOUS PULSE - The CVP is estimated to be 10 cm H 2 O. JUGULAR VENOUS PULSE ECG Question: What is the significance of the jugular venous pulse? 20-2

3 Answer: The jugular venous pulse has a giant a wave (arrow), reflecting enhanced right atrial contraction against increased resistance to outflow, most likely associated with decreased right ventricular compliance. c. ARTERIAL PULSE - (BP = 110/80 mm Hg) UPPER RIGHT STERNAL EDGE CAROTID ECG Question: What is your interpretation of the arterial pulse? 20-3

4 Answer: The arterial pulse is normal. d. PRECORDIAL MOVEMENT and e. CARDIAC AUSCULTATION PRECORDIAL MOVEMENT MID LEFT STERNAL EDGE S1 S2 ECG Question: How do you interpret the precordial movements at the mid-left sternal edge? 20-4

5 Answer: There is a sustained systolic impulse as is typically seen when the right ventricle is after-(pressure) loaded. e. CARDIAC AUSCULATION (continued) RESP EXPIRATION INSPIRATION PHONO UPPER LEFT STERNAL EDGE S1 A 2 P 2 A 2 P 2 ECG 0.1 sec Question: What is the significance of the length of the systolic murmur and the heart sound shown by the arrow at the upper left sternal edge? 20-5

6 Answer: The magnitude of obstruction is a major determinant of the duration of right ventricular ejection which, in turn, determines the length of the systolic murmur. The murmur is moderately long and late-peaking, reflecting relatively severe stenosis. The ejection sound (arrow) increases with expiration and decreases with inspiration, identifying the obstruction at the pulmonary valve level. The sound decreases with inspiration because inspiration augments filling of the nondistensible right ventricle and, in combination with a low pulmonary artery pressure, causes the valve to move toward the open position. With the onset of right ventricular systole, the valve is already in a systolic configuration, and the sound associated with its opening is reduced. Question: What is your explanation for the fact that the pulmonary component of the second heart sound (P2) is not clearly heard in this patient? 20-6

7 Answer: It indicates that the patient has severe stenosis. The intensity of P2 is inversely related to the degree of stenosis, as with greater narrowing there is less valve mobility and lower pulmonary artery diastolic pressure. The sound is delayed in proportion to the severity of the stenosis as right ventricular ejection is prolonged. f. PULMONARY AUSCULTATION Question: How do you interpret the acoustic events in the pulmonary lung fields? Proceed 20-7

8 Answer: In all 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 ECG? 20-8

9 Answer: The ECG shows right axis deviation and right atrial and right ventricular hypertrophy. It also shows ST-T wave abnormalities in leads V1 and V2. CHEST X RAYS Questions: 1. What abnormalities are shown in these chest X rays? 2. Based on the history, physical examination, ECG and chest X rays, what is your initial diagnostic impression and plan to further evaluate this patient? 20-9

10 Answers: 1. The chest X rays show dilation of the pulmonary trunk and the left pulmonary artery (arrow). This is typical of valvular pulmonary stenosis, as the jet flows upwards and to the left. The peripheral vascular markings are normal. In contrast, patients with atrial septal defects demonstrate prominent pulmonary arterial markings bilaterally. 2. The history, physical examination, ECG and chest X rays are characteristic of severe valvular pulmonic stenosis. Echocardiographic study will further define the diagnosis. Proceed 20-10

11 LABORATORY - ECHOCARDIOGRAM The two-dimensional echocardiogram shows a doming, thick pulmonic valve and dilation of the pulmonic trunk. The pulmonary valve annulus is of normal size, enhancing the probability of a successful balloon angioplasty. The continuous wave Doppler follows

12 LABORATORY (continued) CONTINUOUS WAVE ECHO DOPPLER 1 1 M/S The systolic peak velocity (arrow) estimates the pressure difference across the valve to be 100 mm Hg. Because of the severity of the obstruction, cardiac catheterization is indicated, primarily in order to accomplish valvuloplasty. The results of this patient s study follow

13 LABORATORY RIGHT VENTRICULAR ANGIOGRAM ADDITIONAL DATA: MAIN PULMONARY ARTERY (MPA) = 20/10 mm Hg RIGHT VENTRICLE (RV) = 120/5 mm Hg CARDIAC INDEX = 3.0 L / Min / M 2 Questions: 1. How do you interpret this angiogram? 2. How would you treat this patient? LEFT LATERAL 20-13

14 Answers: 1. Contrast is seen passing out of the right ventricle through a hypertrophied infundibulum and then across a dome-shaped stenotic valve (arrows). Post-stenotic dilation of the pulmonary artery is also present. There is a 100 mm Hg gradient between the right ventricle (normal 30/5 mm Hg) and pulmonary artery (normal 30/10 mm Hg), confirming severe pulmonary stenosis. The cardiac index is normal. 2. Treatment is indicated because of the severity of the obstruction. Cardiac catheterization and balloon pulmonic valvuloplasty is the treatment of choice. Angiographic depiction of this procedure follows

15 TREATMENT BALLOON PULMONIC VALVULOPLASTY A B A. Shows indentation (waist) of the balloon at the level of the valve. B. After full expansion the waist is nearly obliterated

16 SUMMARY Congenital obstruction to right ventricular outflow with intact ventricular septum can be valvular, subvalvular or supravalvular. Valvular pulmonic stenosis is the most common type and may be familial. It is usually characterized by a domeshaped narrowing of the valve without identifiable separate leaflets, poststenotic dilation of the main and left pulmonary arteries and secondary right ventricular hypertrophy. In some severe cases the foramen ovale may remain patent and a small right to left shunt may occur. The typical gross pathology follows with the dilated pulmonary artery opened and the stenotic dome-shaped valve well seen

17 PATHOLOGY MAIN PULMONARY ARTERY STENOTIC VALVE RIGHT VENTRICLE Proceed for Case Review 20-17

18 To Review This Case of Congenital Valvular Pulmonic Stenosis: The HISTORY is typical, including murmur heard at birth, years without symptoms, and then diminished exercise tolerance which may proceed to rightsided heart failure. PHYSICAL SIGNS a. The GENERAL APPEARANCE is that of a normal young man. b. The JUGULAR VENOUS PULSE mean venous pressure is moderately elevated and reflects the increased right atrial pressure caused by the thickened less compliant right ventricle. The wave form shows a giant a wave from increased right atrial contraction. Proceed 20-18

19 c. The CAROTID ARTERIAL PULSE is normal. d. PRECORDIAL MOVEMENT reveals a sustained systolic right ventricular impulse. e. CARDIAC AUSCULTATION reveals an ejection sound that diminishes with inspiration, an inaudible pulmonary component of the second sound, and a late-peaking long crescendo-decrescendo murmur best heard in the second left intercostal space. f. PULMONARY AUSCULTATION reveals normal vesicular breath sounds in all lung fields. The ELECTROCARDIOGRAM shows right axis deviation, ST-T wave abnormalities and right atrial and right ventricular hypertrophy. Proceed 20-19

20 The CHEST X RAYS show dilation of the main and left pulmonary arteries. LABORATORY STUDY including echo Doppler evaluation and cardiac catheterization shows elevated right ventricular pressures with a severe pulmonic valve gradient, normal cardiac output and a dome-shaped stenotic valve. TREATMENT is balloon valvuloplasty. Only this type of valvular pulmonary stenosis is amenable to this procedure. Stenosis due to a dysplastic valve or a hypoplastic pulmonary annulus requires surgical therapy