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Query: UMLS:C0033377 (prolapse)
 11,717 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Postexercise systolic time intervals (STI) were measured in ten patients (PMV group) with auscultatory evidence of the midsystolic click syndrome (i.e. one or more systolic nonejection clicks alone or in association with the late systolic murmur), and compared to eight age-matched volunteers (control group) with no evidence of heart disease. Following measurement of supine STIs, the subjects pedalled an upright bicycle ergometer at progressive work loads until a target heart rate (HR) representing 85% of the age-adjusted maximum was attained, or an abnormal end point was noted. Immediately postexercise, a repeat measurement of STIs, was obtained. A shortened or unchanged postexercise left ventricular ejection time corrected for HR (deltaLVETc) and a marked shortening of total electromechanical systole after exercise (deltaQS2c) constituted a normal STI response to stress testing and was noted in all control subjects. All of the PMV group exhibited evidence of left ventricular dysfunction characterized by a prolonged deltaLVETc. It is concluded that an abnormal STI response to exercise consistent with left ventricular dysfunction can be demonstrated in patients with prolapse of the mitral valve by the response of the STI.
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PMID:Postexercise systolic time intervals in the midsystolic click syndrome. 87 54

A contraction abnormality of the left ventricle has previously been described in patients with systolic click-late systolic murmur syndrome. To determine if the contraction abnormality is present in the preprolapse period, LV dimensions and the instantaneous velocity of circumferential fiber shortening (VCF) were studied in 18 patients with the mitral valve prolapse and 16 normal subjects using computer analysis of echocardiograms. VCF attained its maximum (max VCF) during the preprolapse period an average of 94 msec before the mid-systolic click. Max VCF was significantly reduced in patients with mitral valve prolapse (2.06 vs 2.55 circ/sec in normal subjects, P less than 0.001). Despite the reduction in max VCF, no difference in the extent and percentage of diameter shortening was found between patients and normal subjects. This discrepancy is explained by a sustained rate of mid-to-late systolic diameter shortening in the presence of mitral valve prolapse as manifested by a typical VCF profile (P less than 0.001) and a longer duration of diameter shortening (353 vs 306 msec in normal subjects, P less than 0.01). The decrease of max VCF in patients with mitral valve prolapse suggests a reduction in LV contractility. Since the abnormality is present in the preprolapse period, it is unrelated to a direct mechanical effect of the prolapse itself. Additional fiber shortening in mid-to-late systole indicates that the sudden displacement of the mitral leaflets may have an unloading effect on the left ventricle.
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PMID:Abnormal left ventricular contraction pattern in the systolic click-late systolic murmur syndrome. 87 26

Three children with loud systolic honks were studied noninvasively with phonocardiography and echocardiography. It was shown that the precordial honk, like the late systolic mitral murmur and the clicking apical systolic sound, is part of a continuum of auscultatory sounds that result from a defect of mitral valve support and are classified under the general heading of mitral valve prolapse syndrome. Prolapse of one or both of the mitral valve leaflets is believed to cause the characteristic auscultatory findings of click, murmur or honk. The timing of these sounds in systole varies with different physiologic or pharmacologic maneuvers. Variations in the onset of prolapse are associated with changes in left ventricular end-diastolic dimensions.
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PMID:Systolic honks in young children. 87 28

In order to assess the reliability of the echocardiogram in detecting valvular vegetations in patients with mitral valve prolapse (MVP), echocardiograms from 85 consecutive patients with mitral valve prolapse were reviewed. Eleven patients had thick shaggy echoes confined to the anterior mitral leaflet; eighteen patients had shaggy echoes on the posterior leaflet; and five had abnormal echoes on both the anterior and posterior leaflets. Only one patient had clinical evidence of infective endocarditis. Redundant leaflets which present multiple surfaces for the production of echoes may explain the abnormal echoes that were observed. Patients with echographic features suggesting mild prolapse less commonly exhibited shaggy leaflet echoes than those with more severe prolapse. Because a significant proportion (40%) of patients with MVP had shaggy echoes which closely resembled those seen in valvular vegetations, we feel that the echocardiogram is of limited value in diagnosing infective endocarditis in patients with mitral valve prolapse.
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PMID:Limitations of the echocardiogram in diagnosing valvular vegetations in patients with mitral valve prolapse. 88 98

A 24-year-old white man had a history of "epilepsy" since the age of eight years. Prolapse of the mitral valve was documented by auscultation and echocardiographic and left ventriculographic studies. At 120 hours after stopping therapy with phenobarbital and diphenylhydantoin (Dilantin) sodium, continuous electrocardiographic monitoring (Holter monitor) revealed episodes of complete atrioventricular block lasting up to 23 seconds. The results of hemodynamic studies were normal. The patients' symptoms were all totally corrected by implantation of an epicardial demand pacemaker. This report raises the possibility that sudden death in association with the mitral valve prolapse syndrome may be due to intermittent severe disturbances in conduction, in addition to ventricular arrhythmias.
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PMID:Intermittent complete atrioventricular block masquerading as epilepsy in the mitral valve prolapse syndrome. 89 Dec 92

In 26 patients with mitral valve prolapse, ventricular function was evaluated by mean velocity of circumferential fiber shortening (MVCF) as measured along the basilar, middle and apical axes. Significantly increased rates of MVCF were found in patients with mitral prolapse along the basilar axis (1.75 +/- 0.23 circ/sec) and middle axis (2.09 +/- 0.34 cir/sec) (P less than 0.025 and P less than 0.05, respectively). Patients with mitral valve prolapse and regurgitation demonstrated a significant increase in MVCF along the basilar axes (1.72 +/- 0.15 cir/sec) (P less than 0.05). Asynergy apperars to have a negative effect on the MVCF along the middle axis. The MVCF was found not to be related to clinical findings, symptoms or electrocardiographic changes. The mechanism for the increase in MVCF in patients with mitral valve prolapse remains unsettled.
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PMID:Mean velocity of circumferential fiber shortening in prolapsed mitral leaflet syndrome. 91 47

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.
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PMID:Mitral valve prolapse in rheumatic mitral stenosis. 92 8

This study describes seven patients with the mitral valve prolapse or click-murmur syndrome who have survived one or more episodes of life-threatening ventricular arrhythmias. These arrhythmias include cardiac arrest due to ventricular fibrillation, recurrent ventricular tachycardia causing syncope or sustained ventricular tachycardia requiring electroversion. These patients were seen over a two-year period in a single medical center. Five of the seven had repolarization abnormalities in the resting electrocardiogram. Premature ventricular contractions were present in the routine resting electrocardiograms of six of the seven patients and were frequent during treadmill testing and ambulatory electrocardiographic monitoring in all six tested. There were electrolyte abnormalities or changes in medications known to affect myocardial repolarization during the week before the episode in three of the four patients with cardiac arrest. The diagnosis of mitral valve prolapse click-murmur syndrome was made prior to the episode of life-threatening arrhythmia in only two of the seven patients. Varying forms of antiarrhythmic therapy were given to these patients during follow-up periods of five to 26 months. Although the incidence of fatal arrhythmias in the mitral prolapse syndrome is probably small, we suggest that such arrhythmias may not be extremely rare, particularly among those patients who have repolarization abnormalities in the resting electrocardiogram and frequent premature beats. Patients with unexplained ventricular arrhythmias should be screened for mitral valve prolapse.
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PMID:Life-threatening arrhythmias in the mitral valve prolapse syndrome. 93 57

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.
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PMID:Mitral valve prolapse. Recent concepts and observations. 93 60

The cross-sectional echocardiographic features of mitral valve prolapse were defined in 26 children (ages 2-18 years) using a real-time, multiple-crystal ultrasound scanner. In each patient the physical findings of the mitral valve click-murmur syndrome were present and mitral valve prolapse had been diagnosed previously by conventional single crystal echocardiography. Mitral prolapse occurred in a familial setting in eight patients and was associated with the Marfan syndrome in five. Real-time two-dimensional echocardiography uniformly disclosed maximum mitral arching and the superior-posterior prolapse. These visual observations were confirmed by M-mode recordings derived from single elements within the array of 20 crystals. The method allowed a complete M-mode description of the phasic motion of the entire mitral apparatus and observations of the spectrum of prolapse from discrete late systolic prolapse to "hammock-like" holosystolic prolapse. Further, the recording of multiple systolic M-mode lines occurred when the ultrasound beam intersected the arched leaflets more than once. Pseudosystolic anterior motion was observed often and resulted clearly from a superimposition of echoes from the mitral annulus and from the posterior-superiorly arched prolapsed leaflets. A major finding in 22 patients was the association with prolapse of biconvex enlargement of the aortic sinuses of Valsalva and a significant increase in the diameter of the aortic root. Aortic root dilatation was most marked in, but not confined to, patients with the Marfan syndrome and was a prominent finding in six patients with minor musculoskeletal abnormalities. The presence of aortic root dilatation in children with normal body habitus raises important questions concerning the generalized nature of an abnormality of cardiac connective tissue in patients with mitral prolapse. The cross-sectional approach significantly enhances the noninvasive evaluation of mitral valve prolapse and provides an explanation for many of the single crystal observations reported previously.
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PMID:Mitral valve prolapse in children: a problem defined by real-time cross-sectional echocardiography. 94 87


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