Chest
Analysis of QT Interval in Patients with Idiopathic Mitral Valve Prolapse
Section snippets
Patient Selection
Two groups of subjects were included in this study. Croup 1 was composed of 56 patients (44 women and 12 men) with mitral valve prolapse, ranging in age from 18 to 73 years (mean, 46 ± 17 years). To limit this group to patients with IMVP, we excluded patients with Marian's syndrome, a history of rheumatic fever, and clinical or laboratory evidence of other valvular abnormalities, congenital cardiac defects, or cardiomyopathy. Referral to a cardiologist was primarily due to systolic clicks or
Results
The heart rate ranged from 39 to 105 per minute (mean, 74 ± 12) in group 1 and from 38 to 93 per minute (mean, 68 ± 12.5) in group 2.
After correction for age, the maximal QT interval of patients in group 1 exceeded the 97.5 percentile of Simonson and associates2 normal population in 51 patients (91 percent) and was at the upper limits of normal values in the remaining five patients. In the control subjects (group 2) the maximal QT interval exceeded the 97.5 percentile of the normal population
Discussion
Most postulated mechanisms for the arrhythmias associated with IMVP have been related to the mitral valve or left ventricular abnormalities.2,3,4,20,21 Abnormal mitral leaflet motion acting as a mechanical stimulus for generation of ectopic beats as suggested by some workers5 does not explain the intermittent nature of the arrhythmias. Wit and associates20 demonstrated muscle fibers in the mitral leaflet of dogs, which, when exposed to stretching or epinephrine, can initiate atrial arrhythmias.
References (25)
- et al.
Congenital deaf-mutism, functional heart disease with prolongation of the QT interval, and sudden death
Am Heart J
(1957) - et al.
The syndrome associated with mid systolic click and late systolic murmur
Am J Med
(1966) - et al.
Arrhythmias in patients and left ventricular asynergy in the prolapsing mitral leaflet syndrome
Am J Cardiol
(1972) - et al.
Late systolic murmurs and non ejection (mid-late) systolic clicks: an analysis of 90 patients
Br Heart J
(1968) - et al.
Mitral valve prolapse: a review of associated arrhythmias
Am J Med
(1977) - et al.
Arrhythmias on exercise in patients with abnormalities of the posterior leaflet of the mitral valve
Am Heart J
(1972) - et al.
Sudden death and familial occurrence of mid systolic click, late systolic murmur syndrome
Circulation
(1973) - et al.
Refractory ventricular tachycardia and fibrillation in a patient with the prolapsing mitral leaflet syndrome–successful control with overdrive pacing
Am J Cardiol
(1976) - et al.
Etiology and electrocardiographic features of the billowing posterior mitral leaflet syndrome
Am J Med
(1971) - et al.
QT interval prolongation, paroxysmal ventricular arrhythmias, and convulsive syncope
Ann Intern Med
(1971)
Non uniform recovery of excitability in ventricular muscle
Circulation
Quinidine syncope and the delayed repolarization syndromes
Mod Concepts Cardiovasc Dis
Cited by (31)
Arrhythmogenic Mitral Valve Prolapse and Sudden Cardiac Death: An Update and Current Perspectives
2023, Current Problems in CardiologySignificance of QT dispersion on ventricular arrhythmias in mitral valve prolapse
1996, International Journal of CardiologySympathetic and vagal influences on rate-dependent changes of QT interval in healthy subjects
1991, The American Journal of CardiologyPrevalence of QTc prolongation in women with mitral valve prolapse
1989, The American Journal of Cardiology