Open AccessThe Prevalence and the Prognostic Value of Microvolt T‐Wave Alternans in Patients with Hypertrophic Cardiomyopathy
Author(s) -
Trzos Ewa,
Kasprzak Jarosław D.,
Krzemińska–Pakuła Maria,
Rechciński Tomasz,
Wierzbowska–Drabik Karina,
Uznańska Barbara,
Śmiałowski Adam,
Rudziński Tomasz,
Kurpesa Małgorzata
Publication year - 2011
Publication title -
annals of noninvasive electrocardiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.494
H-Index - 48
eISSN - 1542-474X
pISSN - 1082-720X
DOI - 10.1111/j.1542-474x.2011.00443.x
Subject(s) - medicine , t wave alternans , cardiology , hypertrophic cardiomyopathy , ventricular tachycardia , heart rate turbulence , sudden cardiac death , qt interval , cardiomyopathy , ventricular fibrillation , sudden death , heart rate , heart failure , heart rate variability , blood pressure
Background: Nonsustained ventricular tachycardia (nVT) may have ominous implications for patients with hypertrophic cardiomyopathy (HCM). The microvolt T‐wave alternans (TWA) has been proposed as a noninvasive tool‐identifying patients at risk of sudden cardiac death and ventricular tachycardia/fibrillation (VT/VF). The aim of the study was to determine the significance of TWA in predicting nVT episodes and compare how other electrocardiographic parameters can predict the occurrence of nVT. Methods: The study group consisted of 88 patients with HCM. TWA was assessed during exercise test using the CH2000 system. All patients underwent Holter monitoring (HM) within 2–4 weeks before TWA test (preexercise HM1) and immediately after (postexercise HM2). During HM, we analyzed: arrhythmias, QT intervals, the presence of late ventricular potentials (LP), heart rate variability, heart rate turbulence. Results: Depending on TWA results, the patients were divided into two groups: TWA+; 46 patients (52.3%) with positive/indeterminate results, and TWA–; 42 patients (47.7%) with negative results. The nVT episodes were more frequent among TWA(+) both in HM1 and HM2. The presence of TWA increases the risk of postexercise nVT over twenty times (OR = 21.03). Moreover, in HM1, QTc and LP, and in HM2, again QTc and N‐terminal precursor of brain natriuretic peptide proved to be significant predictors of nVT. The addition of TWA to the models did not improve the arrhythmia risk assessment. Conclusions: Repolarization abnormality plays an important role in generating nVT in patients with HCM, but TWA does not specifically predict the risk of arrhythmic end point. Ann Noninvasive Electrocardiol 2011;16(3):276–286