Echocardiographic Abnormalities in Autosomal Dominant Polycystic Kidney Disease (ADPKD) Patients

Cardiovascular abnormalities, such as left ventricular hypertrophy and valvular disorders, particularly mitral valve prolapse, have been described as highly prevalent among adult patients with autosomal dominant polycystic kidney disease (ADPKD). The present study aimed to assess echocardiographic parameters in a large sample of both normotensive and hypertensive ADPKD patients, regardless of kidney function level, and evaluate their association with clinical and laboratorial parameters. A retrospective study consisted of the analysis of clinical, laboratorial, and transthoracic echocardiograms data retrieved from the medical records of young adult ADPKD outpatients. A total of 294 patients (120 M/174 F, 41.0 ± 13.8 years old, 199 hypertensive and 95 normotensive) with a median estimated glomerular filtration rate (eGFR) of 75.5 mL/min/1.73 m² were included. The hypertensive group (67.6%) was significantly older and exhibited significantly lower eGFR than the normotensive one. Increased left ventricular mass index (LVMI) was seen in 2.0%, mitral valve prolapse was observed in 3.4%, mitral valve regurgitation in 15.3%, tricuspid valve regurgitation in 16.0%, and aortic valve regurgitation in 4.8% of the whole sample. The present study suggested that the prevalence of mitral valve prolapse was much lower than previously reported, and increased LVMI was not seen in most adult ADPKD patients.

Understanding the Role of Sex in Heart Valve and Major Vascular Diseases

Cardiovascular disease (CVD) is the major cause of mortality in the elderly population. The cost of CVD treatment and surgeries was over $300 billion in the United States alone in 2010, making this disorder a critical healthcare issue. Many studies have suggested sex as a risk factor for heart valve and major vascular diseases, such as aortic valve stenosis, mitral prolapse and regurgitation, atherosclerosis, coronary artery disease, and abdominal aortic aneurysm. Unfortunately, only a handful of studies have illustrated the role of sex in the etiology and progression of these disorders. Moreover, knowledge of biomolecular factors that affect these diseases in men and women is very limited. Numerous clinical studies have revealed obvious differences in the prevalence of these diseases between the sexes. These reports were supported by a few molecular and cellular physiology studies that associated this difference to sex and sex hormones. In particular, male sex has commonly been identified as a risk factor for majority of heart valve and vascular diseases, whereas females have been identified as higher risk for certain disorders as well. In addition, menopause is a critical issue that turns the tables against women and enhances complications in their cardiovascular structure due to hormonal change. In this review, major vascular and heart valve diseases for which sex is associated as a risk factor have been reviewed to highlight the importance of this risk factor in CVDs.

Mitral valve prolapse in the general population: the benign nature of echocardiographic features in the Framingham Heart Study

OBJECTIVE

The aim of this study was to examine the echocardiographic features and associations of mitral valve prolapse (MVP) diagnosed by current two-dimensional echocardiographic criteria in an unselected outpatient sample.

BACKGROUND

Previous studies of patients with MVP have emphasized the frequent occurrence of echocardiographic abnormalities such as significant mitral regurgitation (MR) and left atrial (LA) enlargement that are associated with clinical complications. These studies, however, have been limited by the use of hospital-based or referral series.

METHODS

We quantitatively studied all 150 subjects with possible MVP by echocardiography and 150 age- and gender-matched subjects without MVP from the 3,491 subjects in the Framingham Heart Study. Based on leaflet morphology, subjects were classified as having classic (n = 46), nonclassic (n = 37), or no MVP.

RESULTS

Leaflet length, MR degree, and LA and left ventricular size were significantly but mildly increased in MVP (p < 0.0001 to 0.004), with mean values typically within normal range. Average MR jet area was 15.1 +/- 1.4% (mild) in classic MVP and 8.9 +/- 1.5% (trace) in nonclassic MVP; MR was severe in only 3 of 46 (6.5%) subjects with classic MVP, and LA volume was increased in only 8.7% of those with classic MVP and 2.7% of those with nonclassic MVP.

CONCLUSIONS

Although the echocardiographic characteristics of subjects with MVP in the Framingham Heart Study differ from those without MVP, they display a far more benign profile of associated valvular, atrial, and ventricular abnormalities than previously reported in hospital- or referral-based series. Therefore, these findings may influence the perception of and approach to the outpatient with MVP.

Exercise-induced mitral regurgitation is a predictor of morbid events in subjects with mitral valve prolapse

OBJECTIVES

This study attempted to determine whether a subset of patients with mitral valve prolapse and no mitral regurgitation at rest will develop mitral regurgitation during exercise and have a higher than anticipated risk of morbid cardiovascular events.

BACKGROUND

Mitral regurgitation in patients with mitral valve prolapse identifies a subset of patients at higher risk for morbid events. However, mitral regurgitation in patients with mitral valve prolapse may be intermittent and could go unrecognized. A provocative test to unmask mitral regurgitation in these patients would be useful.

METHODS

Ninety-four adult patients with mitral valve prolapse and no mitral regurgitation at rest were studied during supine bicycle ergometry using color flow Doppler echocardiography in the apical four-chamber and long-axis views. Patients were prospectively followed up for morbid events.

RESULTS

Thirty (32%) of 94 patients had exercise-induced mitral regurgitation. Prospective follow-up (mean 38 months) showed more morbid events in the group with than without mitral regurgitation and included, respectively, syncope (43% vs. 5%, p < 0.0001), congestive heart failure (17% vs. 0%, p < 0.005) and progressive mitral regurgitation requiring mitral valve replacement surgery (10% vs. 0%, p < 0.05). Cerebral embolic events, endocarditis or sudden death were rare and not different between groups.

CONCLUSIONS

In patients with mitral valve prolapse without mitral regurgitation at rest, exercise provokes mitral regurgitation in 32% of patients and predicts a higher risk for morbid events.

Genes, gender and geometry and the prolapsing mitral valve

Mitral Valve Prolapse (MVP) is usually a variant of normal occurring in about 4% of the population. Complications are relatively uncommon, but false associations due to ascertainment bias have had a potential for iatrogenic harm. Adverse outcomes which do occur in a subset of MVP subjects are considered here in relation to the contributions of genes, gender and geometry. There are definite associations between MVP and several dominantly inherited connective tissue abnormalities; it occurs in 85% of adults with Marfan syndrome. All these contribute to a very small proportion of the MVP population. A larger less easily characterised group with dominant inheritance and some features of a connective tissue disorder awaits DNA studies for identification. For most MVP subjects our data define significant family aggregation consistent with polygenic inheritance; the likelihood of a first degree relative having MVP is about two and a half times the population average. There is a higher prevalence in young women than in men-5% versus 3%; this has also been demonstrated for floppy mitral valve (MV) at autopsy. MVP complications of chordal rupture, severe mitral regurgitation and infective endocarditis are, however, two to three times more common in men, are age related and evident after the age of 50 years. Higher blood pressure in men may contribute to this in accordance with a response-to-injury hypothesis to explain progressive valve changes. Leaflet, annulus and left ventricular size differences and septal changes are geometric variants with a potential for increasing tension-related valve injury.(ABSTRACT TRUNCATED AT 250 WORDS)

Coexistence of mitral valve prolapse in a consecutive group of 528 patients with hypertrophic cardiomyopathy assessed with echocardiography

Hypertrophic cardiomyopathy and mitral valve prolapse are both conditions that may be genetically transmitted and incur a risk for sudden cardiac death. Although the small left ventricular cavity and distorted geometry characteristic of hypertrophic cardiomyopathy might suggest a predisposition to mitral valve prolapse, the frequency with which these two entities coexist and the potential clinical significance of such an association are not known. To further define the relation of hypertrophic cardiomyopathy and mitral valve prolapse, 528 consecutive patients with hypertrophic cardiomyopathy were studied by echocardiography. Patients ranged in age from 1 to 86 years (mean 45); 335 (63%) were male. Unequivocal echocardiographic evidence of systolic mitral valve prolapse into the left atrium was identified in only 16 (3%) of the 528 patients. The mitral valve excised at operation from three of the patients had morphologic characteristics of a floppy mitral valve, which was judged to be responsible for the echocardiographic findings. Occurrence of clinically evident atrial fibrillation was common in patients with hypertrophic cardiomyopathy and mitral valve prolapse (9 [56%] of 16). Hence, in a large group of patients with hypertrophic cardiomyopathy, the association of echocardiographically documented mitral valve prolapse was uncommon. The coexistence of mitral valve prolapse in patients with hypertrophic cardiomyopathy appears to predispose such patients to atrial fibrillation.

Mitral valve prolapse in childhood: the incidence and clinical presentations in different age groups

To elucidate the incidence and natural history of mitral valve prolapse (MVP) during childhood, we investigated a total of 4,238 children (aged from 1 day to 15 years) classified by age into 4 groups: Group 1:1 to 28-day-old full-term normal newborns (n = 108), Group 2: 6 to 18-month-old infants (n = 391), Group 3: 6 to 7-year-old children (n = 2,801), and Group 4: 12 to 15-year-old children (n = 938). The incidence of MVP was determined by videorecorded two-dimensional echocardiography in a double-blind method twice-over. There were 109 cases diagnosed as having MVP. The incidence rates of MVP were as follows: Group 1: 0%, Group 2: 0.25%, Group 3: 2.1% and Group 4: 5.1%. Arrhythmias were detected in 49% (27/55) by Holter ECG, and by exercise stress test in 4.7% (2/43). Eighty-three (77%) of 108 cases in Groups 3 and 4, excluding the 1 case in Group 2, showed no symptoms. Ventricular premature contraction (VPC) was the most common arrhythmia, and was benign in all cases. A mid-systolic click (MSC), late systolic murmur (LSM), MSC + LSM, and a pansystolic murmur were detected in 23.1%, 3.7%, 4.6% and 5.6%, respectively. Symptoms caused by MVP increased and appeared more apparently with age. Further prospective long-term follow-up studies to adulthood are necessary.

Osteogenesis imperfecta in childhood: cardiac and renal manifestations

We examined 58 children aged 1-16 years with various forms of osteogenesis imperfecta (OI). Congenital cardiac malformations were diagnosed in 4 children (valvular aortic stenosis, 2 with atrial septal defect II, Fallot Tetralogy). Two additional children developed holosystolic mitral valve prolapse and regurgitation. Children suffering from a severe clinical course (type III according to the Sillence classification) showed aortic root dilatation (28%) and increased septal (40%) and posterior left ventricular wall thickening (68%) on initial evaluation. All three parameters were significantly correlated to body surface area. Kidney stones and renal papillary calcifications were detected in 4 children. Cardiovascular abnormalities and nephrolithiasis may be important extraskeletal manifestations of childhood OI.

Neurologic aspects of mitral valve prolapse

Mitral valve prolapse (MVP), the most frequently encountered valvular condition in the population, has been reported in an increasing variety of neurologic, muscular, and psychiatric disorders during the last twelve years. Extensive review of reports indicates this has resulted from observations of either (1) inordinate incidence of MVP in well-defined neurologic entities or (2) development of neurologic or ophthalmologic complications attributed to MVP. In the review presented, basis is found for categorizing MVP by its association with (1) well-defined, genetically determined neurologic disorders; (2) disorders characterized by structural abnormalities, many genetically determined, or inflammatory processes of connective tissues; (3) "mechanical" prolapse resulting from disproportion of mitral valve annulus and left ventricular size, which is, at times, reversible; and (4) a generally asymptomatic state that, at times, is associated with ischemic, thrombotic, embolic, and infectious disorders of the brain and eye. The paradox between the large number of persons with MVP in the general population who remain healthy and a subpopulation of patients with complications of MVP (eg, stroke) or other entities has been identified. A second paradox is found between the well-known increased incidence of MVP, especially in young patients with stroke, and the apparent rarity of stroke among patients with both common (eg, migraine) and unusual (eg, myotonic dystrophy) neurologic entities in which an extraordinary high prevalence of MVP is known to exist.

Mitral leaflet billowing and prolapse: its prevalence around the world

Primary mitral leaflet billowing, or so-called mitral valve prolapse, has become the most common valve anomaly in the United States and is also frequently found throughout the world. Its prevalence varies from less than 1% to 38%, differing not only between countries but also within the same country. The prevalence depends on whether the study is clinical or echocardiographic, based on autopsy or surgical material, or of hospital or non-care-seeking population. Other explanations for the varying prevalence are the age, sex and weight differences of the study population, imprecise terminology, the care with which auscultation and/or echocardiography are carried out and interpreted, and some selection biases. Although prevalent throughout the world, the condition is generally benign and can often be regarded as a normal variant. Among the complications of mitral valve prolapse, progressive mitral regurgitation and infective endocarditis are particularly noteworthy. Primary mitral valve prolapse is currently a leading cause of mitral regurgitation and also of infective endocarditis.

Lifetime risk for patients with mitral valve prolapse of developing severe valve regurgitation requiring surgery

Severe mitral regurgitation requiring surgery is the most common life-threatening complication of mitral valve prolapse (MVP) and is due to progressive myxomatous change in the valve. We identified all residents of New South Wales, Australia, who had mitral valve surgery for myxomatous valve disease during 1982 and, using these data and the adult population statistics from 1982, estimated the cumulative risk of valve surgery in patients with MVP. In 1982, 50 of the 5.36 million New South Wales residents required surgery for this complication of MVP. Of the 50, 36 were men and 14 were women, which was significantly different from the population sex distribution (p less than 0.02) for mean age +/- SD of 60 +/- 11 years (range, 26-78 years). Using our previously determined 4% prevalence of adult MVP in New South Wales, we estimated the number of male and female patients with MVP at risk for each 5-year age interval and calculated age-specific event rates. The results show that the cumulative risk is minimal below the age of 50 years but then rises steeply, particularly in men. The risks in men aged 50, 60, and 70 years (with 95% confidence intervals) were 1:202 (130-448), 1:53 (37-82), and 1:28 (22-41), respectively. In women, the risk was less than half that in men (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Reconsideration of echocardiographic standards for mitral valve prolapse: lack of association between leaflet displacement isolated to the apical four chamber view and independent echocardiographic evidence of abnormality

Mitral valve prolapse by current echocardiographic criteria can be diagnosed with surprising frequency in the general population, even when preselected normal subjects are examined. In most of these individuals, however, prolapse is present in the apical four chamber view and absent in roughly perpendicular long-axis views. Previous studies have shown that systolic annular nonplanarity can cause apparent prolapse in the four chamber view without actual leaflet displacement above the most superior points of the anulus, and there is evidence for such nonplanarity in vivo. It is then reasonable to ask whether superior leaflet displacement limited to the four chamber view has any pathologic significance or complications. The purpose of this study, therefore, was to address the following hypothesis: that patients with superior leaflet displacement confined to the four chamber view have no higher frequency of associated echocardiographic abnormalities than do patients without displacement in any view. Such abnormalities, which would provide independent evidence of mitral valve pathology or dysfunction, include leaflet thickening, left atrial enlargement and mitral regurgitation. Leaflet displacement was measured in the parasternal long-axis and apical four chamber views in 312 patients who were studied retrospectively and selected for the absence of forms of heart disease other than mitral valve prolapse. Leaflet thickness and left atrial size were measured and mitral regurgitation was graded. Patients with leaflet displacement limited to the four chamber view were no more likely to have associated abnormalities than were patients without displacement in any view (0 to 2% prevalence, p greater than 0.5). In contrast, patients with leaflet displacement in the long-axis view were significantly more likely to have associated abnormalities (12 to 24%, p less than 0.005), the frequency of which increased with the extent of leaflet displacement in that view (p less than 0.0001). These results suggest that displacement limited to the apical four chamber view is, in general, a normal geometric finding unassociated with echocardiographic evidence of pathologic significance.

Results of screening a large group of intercollegiate competitive athletes for cardiovascular disease

To determine the feasibility of detecting cardiovascular disease in a large group of young competitive athletes, a prospective screening evaluation of intercollegiate student athletes was undertaken at the University of Maryland. Initial clinical screening (including personal and family history, physical examination and 12 lead electrocardiogram) was performed in 501 athletes. Ninety of these subjects had positive findings on one or more of the three studies and agreed to further cardiologic evaluation. The vast majority (75 [84%] of 90) had no definitive evidence of cardiovascular disease, although 1 athlete had mild systemic hypertension and 14 (15%) had echocardiographic evidence of relatively mild mitral valve prolapse that had not been previously suspected. In three athletes with relatively mild ventricular septal hypertrophy (14 to 15 mm), it was not possible to discern with absolute certainty whether the wall thickening was a manifestation of hypertrophic cardiomyopathy or secondary to athletic conditioning ("athlete heart"). Therefore, this screening protocol identified no athletes with definite evidence of hypertrophic cardiomyopathy, Marfan's syndrome or other cardiovascular diseases that convey a significant potential risk for sudden death or disease progression during athletic activity. This failure to identify such diseases could have been due to a lack of sensitivity of the screening tests or to the low frequency with which these diseases occur in youthful healthy athletes. A systematic preparticipation screening program (such as the present one) does not appear to be an efficient means of detecting clinically important cardiovascular disease in young athletes.

Mitral valve prolapse

Mitral valve prolapse is a common mitral valve disorder manifested clinically as a midsystolic click and/or a late systolic murmur (the click-murmur syndrome) and pathologically as billowing or prolapsing mitral leaflets (the floppy valve syndrome). Not only is it one of the two most common congenital heart diseases and the most common valve disorder diagnosed in the United States, but it is also prevalent throughout the world. Mitral valve prolapse may be associated with a variety of other conditions or diseases. Diagnosis of mitral valve prolapse should be made on clinical grounds and, if necessary, supported by echocardiography. The majority of patients with mitral valve prolapse suffer no serious sequelae. However, major complications such as disabling angina-like chest pains, progressive mitral regurgitation, infective endocarditis, thromboembolism, serious arrhythmias, and sudden death may occur. Unless these serious complications occur, most of the patients with mitral valve prolapse need no treatment other than reassurance, including those with atypical chest pain or palpitation unconfirmed by objective data. Therapy with a beta-blocker for disabling chest pain and/or arrhythmias and antiplatelet therapy for cerebral embolic events may be indicated. In occasional patients with significant mitral regurgitation surgery may be necessary.

The relationship of mitral annular shape to the diagnosis of mitral valve prolapse

The geometric or anatomic diagnosis of mitral valve prolapse, as opposed to the pathologic diagnosis of myxomatous valve disease, is based on the relationship of the mitral leaflets to the surrounding anulus. Current echocardiographic criteria for this diagnosis include leaflet displacement above the annular hinge points in any two-dimensional view; implicit in this equivalent use of intersecting views is the assumption that the mitral anulus is a euclidean plane. Prolapse by these criteria is found in a surprisingly large proportion of the general population. In most of these individuals, however, prolapse is present in the apical four-chamber view and absent in roughly orthogonal long-axis views of the left ventricle. This frequently observed discrepancy between leaflet-annular relationships in intersecting views suggests an underlying geometric property of the mitral apparatus that would produce the appearance of prolapse in one view without actual leaflet distortion. To address this possibility, a model of the mitral valve and anulus was constructed. When the model anulus was given a nonplanar, saddle-shaped configuration, the clinical observations were reproduced: the leaflets appeared to lie above the low points of the anulus in one plane, and below its high points in a perpendicular plane. Therefore, the appearance of mitral valve prolapse can occur without actual leaflet displacement above the most superior points of the mitral anulus if the anulus is nonplanar. To determine whether this pattern is reflected in the human mitral anulus, two-dimensional echocardiographic views of the mitral apparatus were obtained by rotation about the cardiac apex in 20 patients without evident annular or rheumatic valvular disease. In all cases the mitral anulus, as reconstructed from these views, had a nonplanar systolic configuration, with high points located anteriorly and posteriorly. This is consistent with the findings of other groups in animals, and would favor the appearance of prolapse in the four-chamber view and its absence in long-axis views that are oriented anteroposteriorly. This model can therefore explain the frequently observed discrepancy between leaflet-annular relationships in roughly orthogonal views. It challenges the assumption that the mitral anulus is planar as well as the diagnosis of prolapse in many otherwise normal individuals based on that assumption.

Mitral valve prolapse and retinal infarction

Several neurological syndromes, including syncope, convulsions, amnesia, transient ischaemic attacks and cerebral infarction, have been associated with mitral valve prolapse. It has been presumed that emboli may account for some of these. We report a case of retinal infarction in association with mitral valve prolapse.

Risk of infective endocarditis in mitral valve prolapse with and without precordial systolic murmurs

The risk of infective endocarditis (IE) associated with a systolic murmur in patients with mitral valve prolapse (MVP) was investigated in a case-control study. The case group comprised all patients with MVP (n = 19) from a series of 136 consecutive adult admissions for IE. Three matched control subjects were chosen for each case from a series of 144 MVP patients without IE. Seventeen of the 19 cases (89%) had documented evidence of systolic murmurs existing before the IE episode; systolic murmurs were documented in 25 of the 57 control subjects (47%). The data indicate a significant increase in the risk of IE in MVP patients with a systolic murmur (p less than 0.01). The absolute probability of IE developing in a patient with MVP and a murmur was estimated to be approximately 1 in 1,400 per year; this was 35 times greater than the probability in a patient with MVP without a murmur. The results suggest that by restricting prophylaxis to MVP patients with a systolic murmur, cover would be provided for almost 90% of those with MVP in whom IE would be likely to develop.

Relation between clinical features of the mitral prolapse syndrome and echocardiographically documented mitral valve prolapse

Mitral valve prolapse, the most common inherited cardiovascular condition, has been associated with a variety of signs, symptoms and electrocardiographic abnormalities, but the true spectrum of the mitral prolapse syndrome remains in doubt because clinical findings often contribute to patient identification and their prevalence in patient groups may be overstated because of ascertainment bias. Accordingly, clinical findings in 88 patients with echocardiographic mitral prolapse were compared with those in 81 of their adult first degree relatives with mitral prolapse (a group free of ascertainment bias) and in two control groups without mitral prolapse: 172 first degree relatives and 60 spouses. Comparison of relatives with and without mitral prolapse demonstrated true associations between mitral prolapse and clicks or murmurs, or both (67 versus 9%, p less than 0.001), thoracic bony abnormalities (41 versus 16%, p less than 0.001), systolic blood pressure less than 120 mm Hg (53 versus 31%, p less than 0.001), body weight 90% or less of ideal (31 versus 14%, p less than 0.005) and palpitation (40 versus 24%, p less than 0.01). In contrast, relatives with mitral prolapse showed no significant increase over normal relatives or spouses without mitral prolapse in prevalence of chest pain, dyspnea, panic attacks, high anxiety or repolarization abnormalities, but these features were all more common in women than in men (p less than 0.01 to less than 0.001). Thus, the true spectrum of the mitral prolapse syndrome encompasses a midsystolic click and late systolic murmur, thoracic bony abnormalities, low body weight and blood pressure and palpitation. Other suggested clinical features, including nonanginal chest pain, dyspnea, panic attacks and electrocardiographic abnormalities, have appeared to be associated with mitral valve prolapse because of ascertainment bias and an erroneous classification of differences between men and women as being due to mitral valve prolapse.

Cardiovascular involvement in osteogenesis imperfecta

While aortic root dilatation and valvular dysfunction have been well-documented in osteogenesis imperfecta (OI), the nature and extent of cardiovascular involvement in OI have not been clearly delineated. A clinical and echocardiographic survey involving 109 individuals with various nonlethal OI syndromes from 66 separate families was undertaken. Clinically discernible valvular dysfunction was encountered in only four of the 109 individuals (aortic regurgitation in two, aortic stenosis in one, and mitral valve prolapse in one), none of whom were related. Aortic root dilatation was recognized echocardiographically in eight (12.1%) of 66 individuals comprising a subset of the sample in which each family was represented by a single individual. The extent of the aortic root dilatation was mild (the largest dimension measuring 4.3 cm) and was unrelated to the age of the individual. Dilatation was seen in each of the different OI syndromes but was strikingly segregated within certain families (p less than .001). In the same subset of 66 individuals, mitral valve prolapse was encountered in two or 6.9% of the 29 individuals aged 15 years or greater in whom adequate studies were obtained. This observed frequency was not different from that seen in a normal adult population. Aortic root dilatation appears to represent a distinct phenotypic trait in patients with OI that is nonprogressive and occurs in about 12% of affected individuals. Whether mitral valve prolapse should be considered as a part of the cardiovascular phenotype in OI, or alternately segregates as an independent autosomal dominant trait has yet to be determined.

Bodily habitus and mitral valve prolapse

We investigated the hypothesis that patients with idiopathic mitral valve prolapse (MVP) have distinctive anthropometric characteristics as part of an ill-defined connective tissue abnormality. In 100 consecutive patients with MVP identified at echocardiography, 56 women and 44 men (age range 28-78 years), we compared measurements of height, weight, arm span, upper and lower body segments, anteroposterior chest diameter, anteroposterior chest diameter/height index, body mass index, and metacarpal index with those from an age and sex matched control group. We also compared the frequency of thoracic asymmetry in MVP patients and controls. Both male and female MVP patients had lower body mass indices than their controls (p less than 0.01 and p less than 0.01 and p less than 0.001, respectively). Women with MVP were lighter than their controls (p less than 0.001) and the same trend was seen in men (p = 0.14). There were no significant differences with any of the other measurements or in the frequency of thoracic asymmetry. We conclude that patients of both sexes with idiopathic MVP are leaner than control subjects but do not otherwise have a specific bodily habitus or an increased frequency of thoracic cage abnormalities. The findings do not support the hypothesis of an underlying generalised connective tissue abnormality but raise the interesting question of why MVP patients should be lean.

Primary (spontaneous) chordal rupture: relation to myxomatous valve disease and mitral valve prolapse

The excised valves of 152 consecutive patients who underwent isolated primary mitral valve replacement between May 1979 and July 1983 were studied to determine the cause of primary (spontaneous) rupture of the chordae tendineae and estimate the prevalence of floppy mitral valve with underlying myxomatous disease. Of these 152 patients, 72 had nonrheumatic disease; 42 (28% of the total group) had a floppy valve, and 39 of these valves had microscopic changes of myxomatous disease. Primary chordal rupture had occurred in 31 patients, including 29 with myxomatous disease. Seven of these patients had prior documentation of mitral valve prolapse and an additional 20 patients had a long-standing murmur. Ischemic mitral regurgitation (22 patients) accounted for the majority of the remaining 30 patients with nonrheumatic disease. Therefore, approximately half of all isolated mitral valve replacements in this institution are now performed for nonrheumatic disease, the majority for a floppy valve in which myxomatous disease was the underlying abnormality. Primary chordal rupture almost invariably occurs as a complication of myxomatous disease, and mitral valve prolapse may be a common precursor.

Prevalence of mitral valve prolapse in normal children

Although echocardiography has become the standard noninvasive method of diagnosing mitral valve prolapse, the diagnostic criteria have been established without clearly defining the range of normal patterns for mitral valve closure. The current study reports the analysis of mitral valve closure patterns in 193 children (aged 5 days to 18 years) making scheduled visits for well child care who were screened by history and physical examination to exclude structural heart disease. Mitral valve systolic leaflet position was analyzed for the appearance of any portion of either leaflet superior to the plane of the anulus. Superior systolic motion was noted in 13% of the overall study group; this pattern was uncommon in infants but more frequent in older children, with a prevalence of 35% in the 10 to 18 year age group. There was no statistically significant difference between male and female children at any age. The prevalence of superior systolic motion decreased markedly if consideration was given to its presence in more than one echocardiographic view (1%) or to displacement of the coaptation point of the mitral valve leaflets (0.5%). Superior systolic motion occurs with such frequency in normal children as to call into question the reliability of this pattern of mitral valve closure as a standard for the diagnosis of mitral valve prolapse. More restrictive diagnostic criteria which consider the degree of leaflet displacement or its presence in multiple echocardiographic views may be necessary to identify those subjects whose mitral valve closure patterns truly fall outside the range of normal.

Mitral valve prolapse and bacterial endocarditis: when is antibiotic prophylaxis necessary?

We investigated the association between mitral valve prolapse (MVP) and bacterial endocarditis (BE) in a case-control study of 56 patients with BE and 168 age- and sex-matched controls who had had echocardiography. Cases and controls were selected from patients without other known cardiovascular risk factors for BE. Twenty percent of the BE cases (11 of 56) and 4% of the controls (7 of 168) had MVP; the odds ratio of 5.3 (95% confidence interval 2.0 to 14.4) indicated a significantly greater risk of BE in patients with MVP. This increased those who had preexisting systolic murmurs (9 of 11). Exposure to repeated vascular instrumentation also increased the risk of BE (odds ratio 6.2, 95% confidence interval 2.3 to 16.4); this was independent of the risk associated with MVP. Based upon these data and the incidence of BE in New South Wales, Australia, in 1980, we estimate that 14 of every 100,000 adult patients with MVP would develop BE over a 1-year period, compared with three people in every 100,000 without other known risk factors for BE in the general population. Thus, although the risk of BE is five times greater in patients with MVP, the absolute risk remains small. This indicates that antibiotic prophylaxis is unnecessary for the majority of patients with MVP. We suggest that for patients with MVP not otherwise known to be at high risk of BE, routine antibiotic prophylaxis should be advised only for those who have systolic murmurs.

Independence of mitral valve prolapse and neurosis

An association has been claimed between mitral valve prolapse and the neuroses, especially the anxiety states, panic disorders, and agoraphobia. In this study 103 patients with echocardiographically confirmed mitral valve prolapse were tested with the Eysenck Personality Inventory for neuroticism and with the General Health Questionnaire for the presence of neurotic symptoms. The scores for neuroticism and neurotic symptoms were not significantly different from those of patients with other cardiac diseases or from those of patients presenting in primary care. In addition 50 patients with agoraphobia were screened by echocardiography for mitral valve prolapse, but no cases were detected. It appears that some of the earlier evidence for an association between mitral valve prolapse and neurosis may have been based on groups which were incorrectly diagnosed. It is concluded that mitral valve prolapse and neurosis are independent conditions.