The late apical systolic murmur. Clinical, hemodynamic and angiographic observations

Abnormal chordal insertion: a cause of mitral valve prolapse

Although the morphology of mitral valve prolapse (MVP) has been described, abnormalities of chordal arrangement and insertion have not been emphasized. We retrospectively reviewed 23 surgically-excised MVP and 10 control mitral valves removed at necropsy. Two-dimensional echocardiograms (2DE) were available in 10 MVP and in six additional controls. 2DE accurately assessed the length of anterior leaflet (AL) and posterior leaflet (PL) of the mitral valve (3.2 +/- 0.7 cm and 2.2 +/- 0.6 cm, respectively) as compared to morphologic measurements (3.0 +/- 0.4 cm and 2.1 +/- 0.4 cm, respectively). However, annular diameter as assessed by echocardiography was significantly less (4.6 +/- 0.7 cm) than that derived by morphologic measurements of annular circumference (AC) (5.3 +/- 0.7 cm). The AL and PL lengths and the mitral anuli were significantly larger in patients with MVP as compared to controls (p less than 0.01) when assessed both by 2DE and by morphology. The ratio of the maximum distance of chordal separation/AC was 0.11 +/- 0.04 in MVP and 0.13 +/- 0.02 in controls (p less than 0.05). Chordal divisions were increased in MVP (4.2) compared to controls (3.1, p less than 0.01). The most striking morphologic feature of MVP was abnormal chordal insertion and a random, unpredictable pattern of chordal distribution. We postulate that abnormal chordal architecture may be responsible for unequal stress on the valve leaflets and may thus lead to MVP.

Mitral valve prolapse: a cardiomyopathic state?

Patients with diseases of the myocardium, structural abnormalities of the heart, and valvular disease may have mitral valve prolapse demonstrated as a consequence of these disease entities. However, there appears to be a primary disease of the mitral leaflets in which left ventricular cineangiography has demonstrated abnormal contraction patterns of the left ventricle in some patients. The cause of these abnormal contraction patterns is controversial, but most of the evidence points to these abnormalities being a consequence of the abnormal leaflet tissue motion during systole creating abnormal stress on the papillary muscles and supporting left ventricle wall. Biopsy evidence of myocardial changes and abnormal cardiac metabolic studies in some patients have suggested that myocardial function may not be entirely normal in every patient with mitral valve prolapse. However, there is not sufficient evidence currently to ascribe these histologic, metabolic and angiographic changes to a primary cardiomyopathic condition.

Anaesthetic considerations in patients with mitral valve prolapse

Mitral valve prolapse (MVP), reported as occurring in up to 17% of healthy individuals, is considered to be the commonest cardiac valvular abnormality. Although the anaesthetic course may be uneventful, complications may arise for the first time in the peri-operative period and include life threatening dysrhythmias, mitral regurgitation and infective endocarditis. Anaesthetic management of three of the seven patients with MVP treated at our institution over a 12-month period is discussed and the literature reviewed.

The floppy mitral valve. Study on pathogenesis

The pathogenesis of the floppy valve syndrome is not fully solved. An almost invariable histological finding is the great accumulation of mucinous material in the valve leaflets and constitutes the basis of the valvular theory of the syndrome. The presence of a mucinous layer in normal valves-- the zona spongiosa--is not well recognised. To establish the normal range of the extent of this zone, 50 excised mitral valves from patients aged 2 to 89 years and who died as a result of road traffic accidents or non-cardiac causes have been analysed by measuring the thickness of the zone in relation to the valve thickness. A range of 0 to 60 per cent was found and this was not influenced by age. The findings were compared with 50 patients clinically diagnosed as suffering from the floppy valve syndrome. A value of over 60 per cent (range 62 to 94%) was found in 43 patients. The increase in the extent of the mucinous material was considered to be a secondary change in the thickened fibrosa which normally accompanies the floppy valve syndrome. Measurements of zona spongiosa falling within the normal range were found in seven patients. The clinical features, complications, and accompanying conditions have also been analysed. Chordal rupture had occurred in 20 patients, infective endocarditis in three, and calcification was found in four valves. In four patients the aortic valve was also involved and accompanying aortic root dilatation in an additional patient. It is suggested that these patients should not be included in the group of Marfan's forme fruste, nor in the typical floppy mitral valve syndrome. Apart from the valvular theory, the myocardial theory in the pathogenesis of the syndrome has been discussed and the components ensuring normal mitral valve function have been reviewed. It is concluded that an inherent, prominent zona spongiosa predisposes to the floppy valve syndrome, particularly if any one of the components of normal valve function is abnormal.

Prevalence of mitral valve prolapse in presumably healthy young men

We determined the prevalence of mitral valve prolapse (MVP) in presumably healthy young men by studying 107 male house officers and medical students with cardiac auscultation in the supine, sitting and standing positions. Echocardiograms were performed at rest in the supine position before and after amyl nitrite inhalation and were obtainable in 101 subjects. Eleven of the 101 subjects had abnormal findings on auscultation: four had an isolated click and seven had a click and late systolic murmur. Correlation of the independent auscultatory and echocardiographic data in the 101 subjects showed that all seven of the subjects with a click and a murmur had echocardiographic evidence of prolapse. None of the 90 subjects with normal auscultation or the four with an isolated click had an abnormal echocardiogram. All seven subjects with MVP had thoracic skeletal abnormalities, but only one was symptomatic. These data suggest that the prevalence of MVP in healthy young males is similar to the reported 6-10% prevalence in healthy young females.

Real-time sector scan study of the mitral valve prolapse syndrome

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Mitral valve prolapse in rheumatic mitral stenosis

Four adult women with histories of rheumatic fever and clinical findings of mitral stenosis and regurgitation had echocardiograms demonstrating moderately severe mitral stenosis (EF slope less than 20 mm/sec, mean left atrial size 3.0 cm/m2, mean anterior mitral leaflet excursion 25 mm) as well as typical mitral valve prolapse. Three patients underwent cardiac catheterization which confirmed the presence of mitral stenosis, as well as systolic prolapse and excessive scalloping of the mitral valve with no visible mitral calcium and no coronary artery disease. One patient had associated mild aortic stenosis and regurgitation. Two patients underwent mitral valve surgery which revealed anterior and posterior commissural fusion consistent with rheumatic disease and intact chordal apparatus. Both leaflets were large and the anterior leaflets were redundant. There were no vegetations. Pathology revealed myxomatous degeneration of the valve leaflets. In the absence of heavy calcification and thickening, the presence of mitral stenosis with commisural fusion does not exclude the possibility of a redundant mitral valve. When these entities coexist, systolic clicks may be absent.

Idiopathic prolapsed mitral leaflet syndrome. Angiographic-clinical correlations

Angiographic clinical correlations were made in 59 patients with prolapsed mitral leaflet syndrome. Eight had nonejection systolic clicks (group I), 20 had early, mid or late systolic murmurs with or without a systolic click (group II), and 31 had pansystolic murmurs (group III). Isolated prolapse of posterior leaflet (PL) scallops occurred in 42 and 17 had combined leaflet prolapse. The study demonstrated the following: (I) Group II patients usually had isolated PL prolapse with a predominant biscallop involvement while a high incidence of triple scallop prolapse and combined mitral leaflet prolapse occurred in group III. (II) Severe mitral regurgitation and a greater incidence of atrial fibrillation were seen in patients with triscallop prolapse and combined mitral leaflet prolapse. Mitral regurgitation was milder in patients with single and biscallop prolapse and, when severe, was associated with ruptured chordae. (III) ST-T wave abnormalities in the inferior leads were most frequent in patients with isolated PL prolapse. (IV) Systolic and diastolic asynergy occurred in 41 patients, most frequently in group II but also relatively frequently in group III (19 of 31). Segmental anterior dysfunction with normal ejection fraction was found in 18 patients, of whom 13 had early anterior wall relaxation. (V) Patients without asynergy were slightly older than those with it. More in the former group had severe mitral regurgitation and were clinically disabled from it.

Surgical treatment of degenerative mitral regurgitation

Between October 1965 and April 1975, mitral valve replacement was preformed in 66 patients with myxomatous degeneration of the mitral valve ("floppy valve syndrome"). Operative mortality was 6 percent (four patients). Current evaluation was obtained for all patients; the average postoperative follow-up interval for surviving patients was 3.5 years (range 1 month to 9.9 years); the total duration of postoperative follow-up for all patients was 180 patient-years. Overall survival rates, calculated by the actuarial method, were 81, 68 and 50 percent, respectively, 1, 2 and 5 years after mitral valve replacement. Preoperative variables with a significantly adverse effect on patient survival included patient age greater than 50 years, New York Heart Association functional class IV, left ventricular end-diastolic pressure greater than 12 mm Hg and mean pulmonary arterial wedge pressure greater than 16 mm Hg. Support is advanced for the concept that mitral valve dysfunction associated with myxomatous degeneration constitutes a broad spectrum of clinicopathologic involvement. Acute clinical and hemodynamic deterioration may often occur in the setting of chronic mitral valve dysfunction. Postoperative mortality is directly related to preoperative functional disability and hemodynamic evidence of impaired left ventricular function. Consideration should be given to earlier operative intervention in patients with myoxmatous mitral degeneration and mitral insufficiency before severe and probably irreversible impairment of ventricular function occurs.

Non-ejection systolic clicks and mitral systolic murmurs in black schoolchildren of Soweto, Johannesburg

A survey was conducted on 12 050 Black schoolchildren, aged 2 to 18 years, in the South Western Townships of Johannesburg (Soweto), and the prevalence of non-ejection systolic clicks and late systolic murmurs was determined. One or both of these auscultatory findings were detected in 168 children, yielding a prevalence rate of 13-99 per 1000 in the school population. A female preponderance of 1-9:1 was present and there was a strong linear increase in prevalence with age, with a peak rate of 29-41 per 1000 in 17-year-old children. A non-ejection click was the only abnormal auscultatory finding in 123 children (73%) and a mitral systolic murmur in 8 (5%), whereas in 37 (22%) both these findings were present. Of the latter 37 children, the murmur was late systolic in 32; in 5 it was early systolic. Auscultation in different postures was important in the detection of both non-ejection clicks and mitral systolic murmurs. Experience in the detection of these auscultatory findings influenced the frequency with which they were heard. Electrocardiographic abnormalities compatible with those previously described in the billowing mitral leaflet syndrome were present in 11 of 158 children. The aetiology of these auscultatory findings in this community remains unknown. In the same survey, a high prevalence rate of rheumatic heart disease was recorded and the epidemiology of the non-ejection clicks and these mitral systolic murmurs showed similarties to that of rheumatic heart disease. Though the specific billowing mitral leaflet syndrome almost certainly accounts for some of these auscultatory findings, a significant proportion may have early rheumatic heart disease. Further elucidation of this problem is necessary.

Mitral valve prolapse. Recent concepts and observations

The conditions associated with prolapse of the posterior leaflet of the mitral valve are multiple. The mechanisms of mitral valve prolapse as well as the pathogenesis of pain and ectopic impulse formation are reviewed. Propranolol appears to be the drug of choice for the symptomatic treatment of patients with this syndrome since it decreases myocardial oxygen demand and wall tension thus reducing or abolishing the discrepancy between myocardial oxygen demand and supply within the mitral apparatus. It has also been reported to modify the auscultatory findings associated with this condition. The frequency of this mitral valve abnormality in patients with obstructive coronary artery disease is reviewed. It appears that prolapse of the posterior leaflet scallops in patients with significant obstructive coronary artery disease represents an intermediate stage before mitral insufficiency occurs. This group of patients with papillary muscle dysfunction includes those with prolapsed leaflets without mitral insufficiency, those with systolic murmurs and compensated heart failure and others with progressive cardiac decompensation and severe mitral regurgitation.

Effect of exercise on left ventricular ejection time in patients with prolapsing mitral leaflet syndrome

The effect of exercise on left ventricular ejection time was determined in 12 subjects with prolapsing mitral valve leaflet syndrome (PML). A single lead ECG (CM5), phonocardiogram and carotid pulse contour were recorded simultaneously with the subjects at supine rest before and immediately after multistage treadmill exercise. Systolic time intervals were measured from five consecutive complexes to determine the pre-ejection period (PEP), left ventricular ejection time (LVET) and total electromechanical systole (QS2). LVET was corrected for heart rate and defines as LVETc. In nine subjects, an increase of 1 to 49 msec was observed in the LVETc following exercise. A shorter resting LVETc and greater afterload at peak exercise was related to an increase in LVETc of 10 msec or more. Exercise elicited or evoked evidence of left ventricular dysfunction. The results support the concept that impaired left ventricular performance is a concomitant of this syndrome.

The systolic click-murmur syndrome: clinical recognition and management

The midsystolic click-late systolic murmur syndrome is a complex entity with variable manifestations that involves a primary process causing myxomatous degeneration of the mitral valve leaflet(s) and subsequent systolic mitral valve leaflet prolapse. Other cardiac diseases may cause mitral valve prolapse and regurgitation associated with a midsystolic click that mimics this primary syndrome. The prolapsing mitral valve leaflet(s) syndrome occasionally may be familial. Most patients are asymptomatic but some complain of chest pain, palpitation, dyspnea or fatigue. Prolapsing mitral valve leaflet(s) can be distinguished from other causes of systolic clicks and mitral regurgitation murmurs by the characteristic movement of the clikmurmur complex in systole with various hemodynamic interventions. The clinical diagnosis usually can be confirmed by echocardiography, which demonstrates the abnormally prolapsdrome usually is minimal but can be progressive and lead to the need for prosthetic valve replacement. Most symptomatic patients can be managed medically but some require cardiac catheterization to evaluate the possibility of coexistent coronary artery disease, to assess the degree of mitral regurgitation and to evaluate other associated cardiac lesions. All patients with this syndrome should receive antibiotic prophylaxis prior to any surgical or dental procedures. Those patients suspected of having arrhythmias should be evaluated by continuous ambulatory ECG monitoring and dangerous arrhythmias probably should be treated. The prognosis usually is excellent, but sudden death and rapidly progressive mitral regurgitation due to ruptured chordae tendineae have been reported. Although more than a decade has elapsed since the midsystolic click-late systolic murmur syndrome was first recognized, much remains to be learned about this common but complex clinical entity.

Double mitral leaflet prolapse: echocardiographic-phonocardiographic correlation

Ten per cent of all patients referred to the echocardiography laboratory for diagnostic evaluation had mitral valve prolapse. Of these 35 patients, 19 (54 per cent) had prolapse of both the anterior and posterior mitral leaflets. Of the 19 patients, 13 had Type A or midsystolic prolapse, whereas six had Type B or pansystolic prolapse of the mitral leaflets. Simultaneous phonocardiographic examination of the patients revealed either midsystolic click and late systolic murmur, pansystolic murmur, or isolated click and short systolic murmur. There was no apparent correlation between the echocardiographic prolapse pattern and the auscultatory events. One patient with Type A prolapse had no auscultatory abnormalities at the time of the examination. It is suggested that the abnormal sounds may be generated by a redundant mitral leaflet rather than chordae tendineae.

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.

Secundum atrial septal defect and mitral valve incompetence

Mitral regurgitation associated with secundum atrial septal defect is described in 4 patients, each with a different mitral lesion: rheumatic valvular disease, congenitally cleft valve, subacute bacterial endocarditis with disruption of the chordae tendineae, and traumatic valve rupture. The pathological spectrum of mitral valve disease associated with atrial septal defect is reviewed, and it is suggested that structural abnormality of the mitral valve may accompany the atrial septal defect. More general awareness of this association will allow the surgeon more accuracy in defining and repairing this rather unusual combination of lesions.

The pathophysiology of idiopathic mitral valve prolapse

Left ventricular structure, function, and the coronary circulation were studied in a subset of patients with mitral valve leaflet prolapse. This group of 26 patients (21 females, five males, with mean age of 46 years), had the syndrome identified as idiopathic mitral valve prolapse (IMVP), which was characterized by a systolic click-murmur, clinical symptoms that were highly variable in duration and intensity, angiographically-documented mitral prolapse, and no obvious associated systemic or cardiovascular disease. Mitral regurgitation was of moderate degree in four, mild in 14, and absent in eight. The left ventricular (LV) end-diastolic volume index was elevated in ten of 25 (40%), the LV mass index was elevated in six of 17 (35%), but the LV anterior wall thickness was increase in only one of 17. Three major patterns of ventricular contraction were identified: 1) normal in seven; 2) abnormal, usually an inferior deformity and/or anterior asynergy, in eight; and 3) hyperkinetic in 11. Normal resting left ventricular function, assessed as an ejection fraction greater than 55%, was present in 17 of 25 (68%). Selective coronary arteriography was essentially normal in all 25 patients studied. An ischemic ECG response was detected during only one of 12 maximal treadmill exercise tests and in none of ten atrial pacing stress tests (AP). Myocardial lactate extraction did not change significantly during AP in six patients. We conclude that cardiomyopathy does not appear to be a primary cause or an important associated component of the IMVP syndrome. Abnormalities of the coronary circulation or of myocardial metabolism were not demonstrated by available methods. A proposed pathophysiological mechanism to explain the clinical and angiographic findings in IMVP is discussed.

Mitral valve prolapse and coronary artery disease. Clinical, hemodynamic, and angiographic correlations

Among 95 patients with angina pectoris and angiographically documented coronary artery disease (CAD), prolapse of the scallops of the posterior leaflet of the mitral valve (PLMV) was noted in 30 patients. Left ventriculograms in the right anterior oblique (RAO) projection revealed isolated prolapse of the posteromedial commissural scallop (PMCS) in 12 patients and the anterolateral commissural scallop (ALCS) in two patients. Seven patients had prolapse of both PMCS and ALCS, three had prolapse of the PMCS and middle scallop (MS), and six had prolapse of all three scallops of the PLMV. Left ventricular dilatation with increase trabeculations was observed in 19 patients. Contractility determined in a quantitative fashion by segmental motion analysis was markedly impaired in 29 patients. None of the patients had angiographic evidence of mitral insufficiency. Left ventricular dysfunction was documented in 28 patients by either elevated left ventricular end-diastolic pressure (LVEDP), low cardiac index (CI) or decreased ejection fraction (EF). In two patients in whom left ventricular contractility improved after aortocoronary by pass, previously prolapsed scallops could not be identified in the postoperative ventriculogram. Prolapsed PLMV is a frequent angiographic finding in patients with angiographically observed CAD. Impaired contractility of the ventricular myocardium and papillary muscles, left ventricular dilatation, and hypertrophy appear to play a significant role in the pathogenesis of this abnormality through distortion of the directional axis of the papillary muscles, asynergic contraction of the related free wall of the left ventricle, and changes in the normal spatial alignment necessary for mitral valve closure. The syndrome of papillary muscle dysfunction in patients with coronary artery disease represents a wider clinical spectrom than previously described.

Late systolic murmur of rheumatic mitral insufficiency

Of 184 patients with acute rheumatic fever and associated mitral insufficiency encountered during a 15 year period, 34 manifested a mid-late systolic murmur or a nonejection click, or both, during the course of follow-up. The mid-late systolic murmur later disappeared in four patients whose condition is now considered normal. In one of the four, systolic prolapse of the mitral valve was demonstrated on an angiocardiogram obtained when the systolic murmur was present. Since disappearance of the murmur there has been no evidence of systolic prolapse on meticulous echocardiographic study of the mitral valve. In another child with angiographically demonstrated systolic prolapse of the mitral valve the systolic murmur has also disappeared, but systolic prolapse is still evident on echocardiographic study. None of the 34 patients with a mid-late systolic murmur manifested the T wave abnormalities commonly associated with the familial variety of mitral valve prolapse.

The variable spectrum of echocardiographic manifestations of the mitral valve prolapse syndrome

The variety of echographic features associated with the mitral valve prolapse syndrome (MVPS) is not yet completely understood. Therefore, ultrasound recordings were obtained in 33 patients in whom mitral prolapse had been documented by biplane left ventricular cineangiography. Echographic abnormailities of the mitral leaflets during systole were recorded in 26/27 MVPS patients and 6/6 with ruptured chordae tendineae. In MVPS, the midsystolic mitral buckling, emphasized in early echocardiographic studies, was observed in only 12 patients. In our study, the most common aberrancy was abnormal pansystolic mitral motion in 14 patients, which in 12 was similar to the pansystolic bowing observed in all six patients with torn chordae. An additional echographic abnormality in MVPS was localized mitral collapse throughout systole in 10/14 patients with pansystolic prolapse; this finding was the most striking defect noted in five, in two of whom it was the only disturbance. Phonocardiography in MVPS showed typical midsystolic click and/or late systolic murmur in only 15/26 patients of whom ten had midsystolic mitral buckling. A variety of systolic clicks and/or murmurs occurred in the 14 patients with generalized bowing and/or localized collapse throughout systole on echocardiography. Thus, the mitral echographic spectrum of MVPS is comprised of three different abnormal patterns of systolic prolapse: buckling in midsystole, pansystolic bowing, and pansystolic collapse. These echocardiographic disorders commonly occur in the absence of classical auscultatory findings in MVPS and the most frequent abnormality on ultrasound is pansystolic bowing of both mitral leaflets.

The syndrome of systolic click, murmur, and mitral valve prolapse--a cardiomyopathy?

Twenty six patients with systolic clicks, murmurs, and prolapsed mitral valve leaflets were studied because of distressing chest pain or troublesome arrhythmias. Cardiac catheterization revealed normal coronary arteries and a high incidence of left ventricular (LV) dysfunction.

The patients, 20 of whom were women, averaged 41 years of age. Thirteen of the 22 patients experienced chest pain of sufficient severity to warrant hospital admission for suspected acute myocardial infarction. Twenty of 26 had abnormal ECG patterns including sinus bradycardia, 1°, 2°, and 3° block, atrial and ventricular arrhythmias and abnormal ST-T wave vectors. Three had patterns of healed transmural infarctions and five of 16 had positive exercise tests.

LV dysfunction was hemodynamically documented in 20 patients by either elevated LV end diastolic pressure, low resting cardiac index, or inappropriate rise in cardiac index during exercise. In the remaining six, impaired LV dynamics were demonstrated angiographically.

Left ventriculography revealed mitral valve prolapse in all patients, mitral regurgitation in 20, and mild to severe LV hypertrophy in 14 patients. Contractility, determined angiographically, was markedly impaired in 13 patients with marked hypokinesis of the antero-lateral wall of the LV resulting in the appearance of an unusual prominent convexity in this portion of the ventricle in end systole and early diastole. Seven others had similar but less severe impairment of LV contractility.

These results indicate that LV dysfunction, possibly related to a primary myocardial disorder, is a significant component of the syndrome of prolapsed mitral valve leaflet. The findings in the symptomatic patients described in this study cannot be generalized to all patients with this syndrome as our sample excluded patients with mild asymptomatic forms of the disease.

Left ventricular abnormalities in prolapsed mitral leaflet syndrome. Review of eighty-seven cases

Eighty-seven patients with proven mitral leaflet prolapse were studied emphasizing cardiodynamics and left ventricular asynergy. Significant associated features were female preponderance (83%), skeletal anomalies (pectus excavatum, straight back, scoliosis, narrow antero-posterior diameter of the chest), and anomalous coronary arteries (cork-screw patterns, short left main coronary artery, anomalous origin of the coronary arteries). Prolapse of the tricuspid leaflets was found in 15 (54%) who had right ventriculography. Five types of abnormal left ventricular systolic contraction patterns were seen in 82% of the cases and these were categorized as: 1) "ballerina foot" pattern (vigorous posteromedial contraction with anterior convexity), 2) "hour glass" pattern (vigorous ring-like contraction involving the middle portion of the left ventricle), 3) inadequate long axis shortening, 4) posterior akinesis, and 5) cavity obliteration pattern. The over-all left ventricular performance was normal generally, as indicated by normal values for functional parameters including left ventricular end-diastolic pressure, cardiac index, ejection fraction, contractility index (stroke work per end-diastolic volume) and pre-ejection period/left ventricular ejection time (PEP/LVET). The myocardial component of the syndrome of prolapsed mitral (and/or tricuspid) leaflets is expressed as asynergistic patterns of ventricular motion and usually does not impair over-all cardiac dynamics.

Familial syndrome of midsystolic click and late systolic murmur

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Midsystolic clicks in arteriosclerotic heart disease. A new facet in the clinical syndrome of papillary muscle dysfunctiion

Midsystolic clicks (MSC), or nonejection systolic clicks, were discovered in 15 patients with arteriosclerotic heart disease (ASHD). The diagnosis of ASHD was established by the presence of angina or the history of a documented myocardial infarction (MI) or both. The MSCs were recorded in 13 patients. A late systolic murmur was introduced by the MSC in four patients, and one patient had a soft holosystolic murmur. The mitral origin of the MSCs and murmurs was established by noting their change in timing and intensity following administration of vasoactive drugs. One patient underwent cardiac catheterization, and evidence of an old MI and papillary muscle dysfunction (PMD) was demonstrated. We think that the PMD that occurs secondary to ischemic fibrosis in ASHD permits slack chordae tendineae suddenly to become taut in midsystole and produce a snap. Although the mechanism for the production of chordal snaps has been previously postulated, ASHD has only recently been found responsible for producing these sounds. The diagnosis of ASHD should be considered in patients with MSCs, even though they frequently occur in its absence.

The praecordial honk

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Association of prolapse of posterior cusp of mitral valve and atrial septal defect

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The varying clinical spectrum of the systolic click-late systolic murmur syndrome

Striking auscultatory variations with changes in posture were observed in 30 individuals with either mid-late systolic clicks, late systolic murmurs, or both, particularly in the upright position. Twenty-seven patients had late systolic murmurs; in nine, however, the murmur was not heard until assumption of the sitting position. Mid-late systolic clicks were heard in 20 patients while supine and in three only on sitting. Click movement (usually toward the first sound) was common during sitting or standing. Late systolic murmurs became holosystolic in 25 patients. In 20, the murmur did not become holosystolic until standing. Systolic whoops, not heard in the supine position, developed on assumption of the sitting position (three patients) or standing (three patients). With prompt squatting, the auscultatory findings reverted to those heard in the supine position in eight of nine patients. All observations were confirmed with phonocardiograms. Structural alterations in the mitral valve complex resulting in systolic prolapse of leaflets into the left atrium occur in these patients. Posture related changes in mitral valve function most likely explain the auscultatory phenomena.

Ballooning deformity (mucoid degeneration) of atrioventricular valves

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The familial occurrence of the syndrome of mid-late systolic click and late systolic murmur

Patients with late systolic murmurs, with and without mid-late systolic extra sounds, have recently been shown to have mitral regurgitation. This syndrome has been found to be familial in each of the four families we have studied. These families were found to have a high prevalence of mid-late systolic extra sounds, late systolic murmurs, pansystolic murmurs, abnormal electrocardiograms, and unexplained premature sudden death.

The prognosis for these patients is unknown but is generally considered good. Periodic medical observation of these patients and their families seems warranted, however, in view of the current lack of knowledge concerning the cause of the chest pain, the rate of progression of the mitral regurgitation, the significance of the electrocardiographic abnormalities, the frequency of important arrhythmias, and the mechanism of sudden death. In addition, antibiotic prophylaxis to attempt to prevent bacterial endocarditis seems clearly indicated.