© 2001 by European Society of Cardiology
ELECTROPHYSIOLOGY
QT dispersion in patients with mitral valve prolapse is related to the echocardiographic degree of the prolapse and mitral leaflet thickness
Department of Cardiology, University Hospital of Heraklion Crete, Greece
Abstract
BACKGROUND: Ventricular arrhythmias are common in patients with mitral valve prolapse (MVP). Previous studies have provided evidence that a higher degree of systolic mitral valve displacement and the presence of a thickened anterior mitral leaflet are related to an increased incidence of complex ventricular arrhythmias and risk of sudden death in these patients. The aim of our study was to investigate whether QT dispersion in patients with MVP is associated with the echocardiographic degree of the prolapse and mitral leaflet thickness.
METHODS: QT and JT intervals and dispersions were measured in 89 patients with primary mitral valve prolapse (26 men and 63 women with mean age 39±14 years). All patients underwent a full echocardiographic examination and a scoring system was used to determine the degree of MVP. Anterior mitral leaflet thickness was also measured. Twenty-four hour Holter monitoring was used to assess ventricular arrhythmogenesis.
RESULTS: According to their echocardiographic score, patients were divided into three groups (Group A, B and C) reflecting the different degrees of the prolapse. QT dispersion in patients with the highest degree of MVP, i.e. Group C was significantly greater (65±13 ms) than that of the other two groups (Group A: 38±14 ms, P< 0·005 and Group B: 45±12 ms, P< 0·005). Similar differences between groups were also found for JT dispersion. Multiple regression analysis revealed that among the demographic and clinical variables that were tested, only the echocardiographic degree of the prolapse and anterior mitral leaflet thickness were independently associated with QT dispersion. Holter monitoring showed that the incidence of complex ventricular arrhythmias was also higher in patients with more severe MVP.
CONCLUSIONS: Our results indicate that QT and JT dispersions are related to the echocardiographic degree of MVP and mitral leaflet thickness. The echocardiographic assessment of the severity of the prolapse may help to identify a subgroup of patients at increased risk of life-threatening arrhythmias.
Key Words: Mitral valve prolapse, QT dispersion, echocardiographic degree of prolapse
Correspondence: Prof. P. Vardas MD, PhD (Lond), FESC, FACC, Department of Cardiology, University Hospital of Heraklion, P.O. Box 1532, Stavrakia, Heraklion, Greece. E-mail: cardio{at}med.uoc.gr
References
[1] Kligfield P, Levy D, Devereux RB, Savage DD. Arrhythmias and sudden death in mitral valve prolapse. Am Heart J 1987; 113: 1298–1307.[CrossRef][Web of Science][Medline]
[2] Devereux RB, Hawkins I, Kramer-Fox R. Complications of mitral valve prolapse: disproportionate occurrence in men and older patients. Am J Med 1986; 81: 751–758.[CrossRef][Web of Science][Medline]
[3] Duren DR, Becker AE, Dunning AJ. Long-term follow-up of idiopathic mitral valve prolapse in 300 patients: a prospective study. J Am Coll Cardiol 1988; 11: 42–47.[Abstract]
[4] Nishimura RA, McGoon MD, Shub C, Miller FA, Ilstrup DM, Tajik AJ. Echocardiographically documented mitral-valve prolapse. Long-term follow-up of 237 patients. N Engl J Med 1985; 313: 1305–1309.[Abstract]
[5] Bekheit SG, Ali AA, Deglin SM, Jain AC. Analysis of QT interval in patients with idiopathic mitral valve prolapse. Chest 1982; 81: 620–625.
[6] Puddu PE, Pasternac A, Tubau JF, Krol R, Farley L, de Champlain J. QT interval prolongation and increased plasma catecholamine levels in patients with mitral valve prolapse. Am Heart J 1983; 105: 422–428.[CrossRef][Web of Science][Medline]
[7] Gooch AS, Vicencio F, Maranhao V, Goldberg H. Arrhythmias and left ventricular asynergy in the prolapsing mitral leaflet syndrome. Am J Cardiol 1972; 29: 611–620.[CrossRef][Web of Science][Medline]
[8] Tieleman RG, Crijns HJ, Wiesfeld AC, Posma J, Hamer HP, Lie KI. Increased dispersion of refractoriness in the absence of QT prolongation in patients with mitral valve prolapse and ventricular arrhythmias. Br Heart J 1995; 73: 37–40.
[9] Kulan K, Komsuoglu B, Tuncer C, Kulan C. Significance of QT dispersion on ventricular arrhythmias in mitral valve prolapse. Int J Cardiol 1996; 54: 251–257.[CrossRef][Web of Science][Medline]
[10] Boudoulas H, Kolibash AJ, Baker P, King BD, Wooley CF. Mitral valve prolapse and the mitral valve prolapse syndrome: a diagnostic classification and pathogenesis of symptoms. Am Heart J 1989; 118: 796–818.[CrossRef][Web of Science][Medline]
[11] Malkowski MJ, Boudoulas H, Wooley CF, Guo R, Pearson AC, Gray PG. Spectrum of structural abnormalities in floppy mitral valve echocardiographic evaluation. Am Heart J 1996; 132: 145–151.[CrossRef][Web of Science][Medline]
[12] Sahn DJ, DeMaria A, Kisslo J, Weyman A. Recommendations regarding quantitation in M-mode echocardiography: results of a survey of echocardiographic measurements. Circulation 1978; 58: 1072–1083.
[13] Labovitz AJ, Pearson AC, McCluskey MT, Williams GA. Clinical significance of the echocardiographic degree of mitral valve prolapse. Am Heart J 1988; 115: 842–849.[CrossRef][Web of Science][Medline]
[14] Stoddard MF, Prince CR, Dillon S, Longaker RA, Morris GT, Liddell NE. Exercise-induced mitral regurgitation is a predictor of morbid events in subjects with mitral valve prolapse. J Am Coll Cardiol 1995; 25: 693–699.[Abstract]
[15] Helmcke F, Nanda NC, Hsiung MC, et al. Colour Doppler assessment of mitral regurgitation with orthogonal planes. Circulation 1987; 75: 175–183.[Medline]
[16] Malik M and Camm AJ. Mystery of QTc interval dispersion. Am J Cardiol 1997; 79: 785–787.[CrossRef][Web of Science][Medline]
[17] Zabel M, Woosley RL, Franz MR. Is dispersion of ventricular repolarization rate dependent? Pacing Clin Electrophysiol 1997; 20: 2405–2411.[CrossRef][Medline]
[18] Lown B and Wolf M. Approaches to sudden death from coronary heart disease. Circulation 1971; 44: 130–142.
[19] Freed LA, Levy D, Levin RA, et al. Prevalence and clinical outcome of mitral-valve prolapse. N Engl J Med 1999; 341: 1–7.
[20] Marks AR, Choong CY, Sanfilippo AJ, Ferre M, Weyman AE. Identification of high-risk and low-risk subgroups of patients with mitral-valve prolapse. N Engl J Med 1989; 320: 1031–1036.[Abstract]
[21] Sanfilippo AJ, Abdollah H., Burggraf GW. Quantitation and significance of systolic mitral leaflet displacement in mitral valve prolapse. Am J Cardiol 1989; 64: 1349–1355.[Medline]
[22] Zuppiroli A, Mori F, Favilli S, et al. Arrhythmias in mitral valve prolapse: relation to anterior mitral leaflet thickening, clinical variables, and colour Doppler echocardiographic parameters. Am Heart J 1994; 128: 919–927.[CrossRef][Web of Science][Medline]
[23] Kuo CS, Reddy CP, Munakata K, Surawicz B. Mechanism of ventricular arrhythmias caused by increased dispersion of repolarization. Eur Heart J 1985; 6: 63–70.
[24] Vassallo JA, Cassidy DM, Kindwall KE, Marchlinski FE, Josephson ME. Non-uniform recovery of excitability in the left ventricle. Circulation 1988; 78: 1365–1372.
[25] Sanfilippo AJ, Harrigan P, Popovic AD, Weyman AE, Levine RA. Papillary muscle traction in mitral valve prolapse: quantitation by two-dimensional echocardiography. J Am Coll Cardiol 1992; 19: 564–571.[Abstract]
[26] Gornick CC, Tobler HG, Pritzker MC, Tuna IC, Almquist A, Benditt DG. Electrophysiologic effects of papillary muscle traction in the intact heart. Circulation 1986; 73: 1013–1021.
[27] Boudoulas H, Schaal SF, Wooley CF. Floppy mitral valve/mitral valve prolapse: cardiac arrhythmias. In Vardas PE (Ed.). Cardiac arrhythmias, pacing and electrophysiology 1998; London Kluwer Academic Publishers pp. 89–95.
[28] Kochiadakis GE, Parthenakis FI, Zouridakis EG, Rombola AT, Chrysostomakis SI, Vardas PE. Is there increased sympathetic activity in patients with mitral valve prolapse? Pacing Clin Electrophysiol 1996; 19: 1872–1876.[CrossRef][Medline]
[29] Boudoulas H, Reynolds JC, Mazzaferri E, Wooley CF. Metabolic studies in mitral valve prolapse syndrome. A neuroendocrine-cardiovascular process. Circulation 1980; 61: 1200–1205.
[30] Pasternac A, Tubau JF, Puddu PE, Krol RB, de Champlain J. Increased plasma catecholamine levels in patients with symptomatic mitral valve prolapse. Am J Med 1982; 73: 783–790.[CrossRef][Web of Science][Medline]
[31] Opthof T, Misier AR, Coronel R, et al. Dispersion of refractoriness in canine ventricular myocardium. Effects of sympathetic stimulation. Circ Res 1991; 68: 1204–1215.
[32] Boudoulas H and Wooley CF. Floppy mitral valve/mitral valve prolapse: sudden death. In Boudoulas H and Wooley CF (Eds.). Mitral valve: floppy mitral valve, mitral valve prolapse, mitral valvular regurgitation, 2nd revised edition 2000; Armonk Futura Publishing, Inc pp. 464–493.
[33] Malik M and Batchvarov V. Measurement, interpretation and clinical potential of QT dispersion. J Am Coll Cardiol 2000; 36: 749–766.
[34] Jordaens LJ. The clinical value of QT dispersion: new perspectives on the assessment of cardiac repolarization more than 75 years after Bazett's formula. Europace 1999; 1: 73–76.
[35] Zareba W, Moss AJ, le Cessie S. Dispersion of ventricular repolarization and arrhythmic cardiac death in coronary artery disease. Am J Cardiol 1994; 74: 550–553.[CrossRef][Web of Science][Medline]
[36] Galinier M, Vialette JC, Fourcade J, et al. QT interval dispersion as a predictor of arrhythmic events in congestive heart failure. Importance of aetiology. Eur Heart J 1998; 19: 1054–1062.
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