Systolic clicks: A clinical, phonocardiographic, and hemodynamic evaluation

Localization of the origin of systolic clicks using echo-pulsed Doppler technique

Echo-pulsed doppler (EPD) studies were performed in 2 surgically controlled patients with systolic clicks. The recorded blood samples documented the click to be originated in the right atrium, at the site of the prolapsed anterior tricuspid leaflet in 1 case of heroin-induced tricuspid acute endocarditis. In the second patient suffering from aortic valve disease, an ejection click was recorded, and could be demonstrated by using EPD, to originate from the aortic leaflet at its time of maximal excursion. EPD apears to be a safe, noninvasive method to solve the problem of the origin of systolic clicks.

Echocardiographic and hemodynamic relationships of ejection sounds

The physiologic correlates of ejection sounds have been studied by simultaneous phonocardiograms, echocardiograms and high fidelity pressure tracings. Ejection sounds associated with semilunar valve stenosis or hypertension of the systemic or pulmonary circulation occur at the moment of complete opening of the aortic or pulmonary valve recorded echocardiographically. The start of opening of these valves occurs at the onset of the pressure rise in the corresponding great vessel and completion of valve opening always occurs on the pressure upstroke. The ejection sound in the presence of stenotic valves occurs with checking of the opening motion of the thickened valve cusps. Although the hypertensive ejection sounds also occur at the precise moment of full opening of the valve it remains to be seen whether this relationship is causal or coincidental.

Mitral valve prolapse in one hundred presumably healthy young females

Clinical, electrocardiographic, phonocardiographic, and echocardiographic examinations were performed in 100 presumably healthy young females. Treadmill testing and ambulatory electrocardiographic monitoring were performed in a selected group of these subjects. Phonocardiograms, recorded with the subjects supine at rest, after inhalation of amyl nitrite, and in the upright position, revealed a 17% incidence of nonejection clicks and/or late or mid- to late systolic murmurs (PHONO-MSCLSM). Echocardiographic studies were performed in the second, third, fourth, and fifth intercostal space with emphasis on the importance of transducer angulation on the chest. Studies obtained with the transducer perpendicular to the chest in the sagittal plane, or pointing cephalad at a time when both mitral leaflets and left atrium are recorded, are optimal to study the mitral valve systolic motion. With the transducer in this position, 21 subjects were found to have pansystolic or late systolic prolapse, as previously defined on the echocardiogram. The presence of these echocardiographic findings was statistically related to the presence of PHONO-MSCLSM. Other echocardiographic patterns were identified and their relation to PHONO-MSCLSM and transducer position is discussed. Ten subjects with both echocardiographic evidence of mitral valve prolapse and PHONO-MSCLSM were identified (group EP), while 18 other subjects had either echocardiographic or phonocardiographic findings suggestive of mitral valve abnormality (group EorP). Seventy-two subjects had no abnormality (group noEP). The incidence of various clinical, electrocardiographic, and echocardiographic findings in these three groups was determined. Some findings said to be common in patients with proven mitral valve prolapse were seen more frequently in group EP subjects. Echocardiographic and phonocardiographic findings suggesting mitral valve abnormalities were found more commonly than expected in a population of presumably healthy young females.

The problem of nonejection systolic clicks and associated mitral systolic murmurs: emphasis on the billowing mitral leaflet syndrome

Nonejection clicks and associated mitral systolic murmurs are common in routine cardiologic practice and can result from multiple etiologic factors affecting the complex mitral valve mechanism. Such factors include a specific syndrome the essential feature of which is that the mitral leaflets or part thereof, primarily the posterior one, are voluminous. The syndrome has stimulated widespread interest and study during the last decade and various descriptive terms, including the "billowing mitral leaflet syndrome" (BMLS), have been applied to it. A familial occurrence of the BMLS may be detected and symptoms include chest pain, palpitations, syncope, and anxiety. Arrhythmias, conduction defects, and ECG abnormalities which mimic occlusive coronary artery disease are important features which remain ill understood. It is suggested that there is a possible relationship between the so-called "athlete's heart" and the BMLS. We also postulate that the entity of acute myocardial infarction without demonstrable occlusive coronary artery disease is, in at least some instances, a complication of the BMLS-possibly on the basis of coronary spasm. More severe mitral regurgitation, infective endocarditis, or, rarely, sudden death may supervene in the BMLS but we conclude, from published data and our own experience, that the prognosis is generally good.

First heart sound and ejection sounds. Echocardiographic and phonocardiographic correlation with valvular events

To provide additional information on the relation of valvular events to the principal components of the first heart sound (s1), combined echocardiograms and phonocardiograms were recorded in 49 subjects, chosen because of audible splitting of S1 or a combination of S1 and an ejection sound. The subjects included 14 normal persons, 16 patients with a variety of predominantly right-sided heart conditions, 7 with mitral stenosis, 3 with pulmonary stenosis and 9 with aortic valve disease or systemic hypertension. A precise relation was found between completion of closure of the atrioventricular (A-V) valves manifested in the echocardiogram and the high-frequency components of S1 (M1 and T1). The average time from the Q wave of the electrocardiogram to M1 was 0.06 plus or minus 0.003 second and the Q-T1 interval was 0.09 plus or minus 0.002 second. In mitral stenosis the Q-M1 interval was delayed to 0.10 plus or minus 0.005 second, resulting in some instances in reversed splitting of S1. In pulmonary stenosis, the ejection sound occurred 0.10 plus or minus 0.003 second from the Q wave. In 7 of the 16 patients with various right-sided abnormalities, but without valvular stenosis, an ejection sound of pulmonary origin occurred 0.18 plus or minus 0.012 second from the Q wave. In the nine patients with aortic valve disease or systemic hypertension, the time from the Q wave to the aortic ejection sound was 0.13 plus or minus 0.004 second. With only two exceptions the ejection sounds of aortic and plumonary origin coincided exactly with achievement of a fully opened position of the respective semilunar valve. Our findings support the postulate that M1, T1 and the ejection sounds occur in association with closing or opening of valves with consequent sudden deceleration or acceleration of a column of blood that, in turn, results in vibrations of the cardiohemic system and audible sounds.

Auscultatory recognition of aneurysm of the membranous ventricular septum associated with small ventricular septal defect

The clinical diagnosis of aneurysmal formation of the membranous ventricular septum associated with a small ventricular defect has been made previously only by means of angiocardiography.

Active movement of the aneurysm during cineangiocardiography suggested the possibility of a corresponding auscultatory event. When careful auscultatory and phonocardiographic examinations were performed on 21 patients previously documented as having a small membranous ventricular defect with an associated aneurysm, a distinct early systolic sound was heard in 17 (81%). This sound was "clicky" in quality, confined to a narrow area along the lower left sternal edge, and best heard in expiration. It occurred during the upstroke of the carotid arterial tracing and followed the Q wave by 100 to 130 msec.

On the basis of experience with other patients the development of this early systolic sound in a patient with a small ventricular septal defect suggests the diagnosis of associated septal aneurysm, but such a sequence requires confirmation by serial angiocardiography. Aneurysmal formation may be a prelude to spontaneous closure of the septal defect in which case auscultation of an early systolic sound should not only prove to be a valuable diagnostic sign for the clinician but may also be of considerable prognostic significance for the patient.

The ejection click of valvular pulmonic stenosis

Ten patients with valvular pulmonic stenosis were studied by simultaneous external phonocardiograms and intracardiac pressure recordings during successive respiratory cycles to examine the mechanism of the respiratory variation in the ejection click. Selective cineangiograms were performed in four. During inspiration right ventricular end-diastolic pressure (RVEDP) exceeded the pressure in the pulmonary artery (+2.7 mm) and no ejection click was recorded. During expiration RVEDP was lower than the pressure in the pulmonary artery (-3.6 mm) and a click was recorded. The click was present throughout the respiratory cycle when pulmonary artery diastolic pressure consistently exceeded RVEDP. Clicks were associated with sudden "doming" of the valve demonstated by cineangiography. These data support the valvular origin of the ejection click in pulmonic stenosis and provide the following explanation for the respiratory variation: Inspiratory increase in venous return causes the valve leaflets to move to an open or "domed" position. Ventricular systole at this time produces no sound since there is no slack. With expiration pulmonary artery pressure exceeds RVEDP. Ventricular systole at this time produces an opening motion of the closed, slack leaflets. The click occurs when the opening motion is suddenly checked.

Sound-pressure correlates of the aortic ejection sound. An intracardiac sound study

The sound-pressure correlates of the aortic ejection sound (AES) were studied in six patients without aortic valve disease (group 1) and in nine patients with valvular aortic stenosis (group 2) during diagnostic left heart catheterization. Aortic root sound and pressure events were recorded by a catheter-tip micromanometer simultaneously with the external phonocardiogram, indirect carotid pulse, and electrocardiogram. The AES in group 1 patients was coincident with the onset of pressure rise in the aortic root. This relationship was not altered by drug administration, although variations in the amplitude of the AES occurred. It was concluded that the AES in patients without aortic valvular disease is an exaggerated ejection component of the normal first heart sound, and that it is a root phenomenon related to the forceful ejection of blood into the aorta. The AES in group 2 patients was delayed 24 to 40 msec after the onset of pressure rise in the aortic root, was coincident with the anacrotic notch, and introduced the aortic ejection murmur. Aortic root sound and pressure were recorded simultaneously with aortic valve motion during angiography in two patients utilizing a cine trace system. The AES occurred when the domed valve reached its maximal excursion, and the interval between the onset of aortic pressure rise and the AES was equal to the total time required for the piston-like ascent of the dome. It was concluded that the AES in valvular aortic stenosis is valvular in origin. The amplitude of the valvular AES correlated best with valve mobility on the angiogram, and no correlation existed between its presence and the severity of the valvular stenosis.

Assessment of site and severity in congenital aortic stenosis

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Early systolic sounds in aortic valve stenosis

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Cineradiographic Studies of the Early Systolic Click in Aortic Valve Stenosis

An early systolic click and a normal or accentuated aortic second sound have been found in cases of aortic valve stenosis characterized cineradiographically by a mobile, dome-shaped valve. Impaired valve mobility was usually associated with a systolic click of low intensity, and in the presence of an immobile aortic valve there was no systolic click. The aortic second sound was correspondingly diminished or absent.

Early systolic clicks and loud aortic closure sounds were also present in patients in whom a diseased aortic valve had been replaced by three Teflon prosthetic leaflets. In most of these patients there was no systolic click before insertion of the prosthesis.

In the patients studied, the systolic click occurred at the end of the opening movement of the aortic valve at the onset of left ventricular ejection. It followed the crossover point of the left ventricular and aortic pressure pulses by a time interval ranging from 15 to 45 msec. (average 33 msec.).

The opening movement of the valve was thought to produce the systolic click by causing sudden tension of the valve membrane or sudden alteration in the velocity of blood flow. By analogy with the opening snap in mitral stenosis, the early systolic click may be regarded as the "opening snap" of the aortic valve. A systolic click is clinical evidence of a mobile aortic valve in patients with aortic valve disease.

Hemodynamic Correlates of the Various Components of the First Heart Sound

Previous studies in this laboratory having demonstrated that AV valve closure is not directly responsible for the rapid vibrations of the first heart sound, the mechanism of production of this "sound" was studied further in 30 experiments in dogs. The experiments were performed with multiple pressure catheterization, and intracardiac phonocatheterization, and were compared with external phonocardiograms and electrocardiograms. In 10 experiments, the first derivatives of the left and right ventricular pressures were also recorded. In four experiments, direct epicardial and arterial sound tracings were obtained.

These experiments revealed that three groups of vibrations, or components, were often visible in the external phonocardiogram, and in intracardiac and epicardial tracings. The first component follows the onset of left ventricular pressure rise and closure of the mitral valve but coincides with the rapid rise of the first derivative of LV pressure. The second component has no relationship with right heart events, occurs before aortic valve opening, and coincides with the sudden change of course of the first derivative of LV pressure. The third component occurs slightly after aortic valve opening, and seems related to sudden increase of aortic wall tension. It is probably the physiological equivalent of the aortic "ejection sound." Thus, the first two components are both left ventricular in origin while the third is of aortic origin.

Stenosis of the Right Main Pulmonary Artery

Ten cases of isolated stenosis of the right main pulmonary artery are presented, 7 with associated anomalies. Although right heart catheterization and angiocardiography are usually necessary to demonstrate this malformation, a knowledge of the existence of this anomaly correlated with auscultatory and roentgenologic findings may often lead to a correct clinical diagnosis.