Sudden Cardiac Death in Mitral Valve Prolapse
To the Editor:
I read with interest the excellent report on sudden cardiac death with apparently normal heart by Chugh et al.1 Of note was the finding that 28 of 270 hearts (10%) had pathological criteria for mitral valve prolapse. In addressing the association between mitral valve prolapse and sudden cardiac death, the authors classified these hearts as having a nonspecific structural abnormality. Such an assumption is open to question.
Evidence to date suggests that the predominant mechanism of sudden cardiac death in mitral valve prolapse is fatal ventricular arrhythmias.2 Therefore, it would be extremely difficult for a pathological study such as that by Chugh et al1 to prove or disprove conclusively the causal relation between mitral valve prolapse and sudden cardiac death.
Whether mitral valve prolapse claimed the life of Shylock in the Merchant of Venice, who claimed the heart of Portia’s lover,3 or Antonia in the Tales of Hoffman, who sang herself to death,4 there is no question that although generally a benign condition, mitral valve prolapse may be a deadly disease at times.5 Admittedly, mitral valve prolapse is an uncommon cause of sudden cardiac death,2 and its propensity to cause sudden death has been of major concern mainly because of the high frequency of this abnormality in the general population.5
- Copyright © 2001 by American Heart Association
Chugh SS, Kelly KL, Titus JL. Sudden cardiac death with apparently normal heart. Circulation. 2000;102:649–654.
Barlow JB, Cheng TO. Mitral valve billowing and prolapse. In: Cheng TO, ed. The International Textbook of Cardiology. New York: Pergamon Press; 1987:497–524.
Stefanadis C, Toutouzas P. Mitral valve prolapse: the Merchant of Venice or Much Ado About Nothing? Eur Heart J. 2000;21:255–258.
Cheng TO. Mitral valve prolapse: the Merchant of Venus or the Tales of Hoffman? Eur Heart J. In press.
In his insightful letter, Professor Cheng appropriately questions our assignment of cases of sudden cardiac death with mitral valve prolapse to the subgroup of “structural abnormality, nonspecific findings.”
Two factors influenced this categorization. Although mitral valve prolapse has been associated with sudden death, the causal relationship between the 2 entities remains controversial.R1 R2 R3 The significant incidence of mitral valve prolapse in the general population and extremely low risk of sudden death have led to the recommendation of reassurance as a major part of medical management for this condition.R4 Another factor for our cautious approach was that although abnormalities of the atrioventricular nodal artery have been reported in association with mitral valve prolapse and sudden cardiac death,R5 we did not complete detailed morphological studies of this vessel as a part of our investigation.
We are grateful to Dr Cheng for his comments and pleased that he found our article of interest. However, as far as we can tell, the conclusion of the Merchant of Venice finds Shylock outwitted, but alive and well. If he were to die suddenly, may we venture the opinion that the aging Shylock is most likely to succumb to coronary artery disease? For the 19-year old Antonia’s familial malady in the Tales of Hoffman, should we not consider hypertrophic cardiomyopathy, long-QT syndrome, or familial dilated cardiomyopathy among the differential diagnoses?
Chesler E, Gornick CC. Maladies attributed to myxomatous mitral valve. Circulation. 1991;83:328–332.
Chesler E, King RA, Edwards JE. The myxomatous mitral valve and sudden death. Circulation. 1983;67:632–639.
Titus JL, Kelly KL, Edwards JE. Sudden cardiac death: the frequency of its common causes in women versus men. Med J Allina. 2000;9(suppl):24–26.
Bonow RO, Carabello B, de Leon AC Jr, et al. Guidelines for the management of patients with valvular heart disease: executive summary: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee on Management of Patients with Valvular Heart Disease). Circulation. 1998;98:1949–1984.