OBJECTIVES: The aim of this study was to clarify the clinical significance and the determinant of microvolt-level T-wave alternans (TWA) in patients with dilated cardiomyopathy (DCM). BACKGROUND: The prevention of sudden death in patients with DCM remains the therapeutic target. T-wave alternans has been proposed as a powerful tool for identification of patients at high risk for ventricular arrhythmias and sudden death in coronary artery disease. METHODS: In 58 DCM patients, TWA was measured during bicycle exercise testing using a CH 2000 system (Cambridge Heart, Bedford, Massachusetts). The New York Heart Association class, signal-averaged electrocardiogram, QT dispersion, left ventricular end-diastolic diameter (LVDd) and percent fractional shortening detected by echocardiogram and the grade of the ventricular arrhythmia were obtained in all patients. RESULTS: T-wave alternans was positive in 23 patients (TWA+ group), negative in 25 (TWA- group) and indeterminate in 10. Univariate analysis showed that the percentage of patients with ventricular tachycardia (VT) and the LVDd in the TWA+ group was significantly higher than those in the TWA- group (61% vs. 8%, p < 0.001 and 65 +/- 11 mm vs. 58 +/- 8 mm, p < 0.05, respectively). The sensitivity, specificity and predictive accuracy of TWA for VT were 88%, 72% and 77%, respectively. Multivariate analysis showed that the presence of VT was a major independent determinant of TWA in patients with DCM (p = 0.003). CONCLUSIONS: T-wave alternans was closely related to VT in patients with DCM. T-wave alternans is a useful noninvasive test for identifying high risk patients with DCM who have VT.
OBJECTIVES: The aim of this study was to clarify the clinical significance and the determinant of microvolt-level T-wave alternans (TWA) in patients with dilated cardiomyopathy (DCM). BACKGROUND: The prevention of sudden death in patients with DCM remains the therapeutic target. T-wave alternans has been proposed as a powerful tool for identification of patients at high risk for ventricular arrhythmias and sudden death in coronary artery disease. METHODS: In 58 DCMpatients, TWA was measured during bicycle exercise testing using a CH 2000 system (Cambridge Heart, Bedford, Massachusetts). The New York Heart Association class, signal-averaged electrocardiogram, QT dispersion, left ventricular end-diastolic diameter (LVDd) and percent fractional shortening detected by echocardiogram and the grade of the ventricular arrhythmia were obtained in all patients. RESULTS: T-wave alternans was positive in 23 patients (TWA+ group), negative in 25 (TWA- group) and indeterminate in 10. Univariate analysis showed that the percentage of patients with ventricular tachycardia (VT) and the LVDd in the TWA+ group was significantly higher than those in the TWA- group (61% vs. 8%, p < 0.001 and 65 +/- 11 mm vs. 58 +/- 8 mm, p < 0.05, respectively). The sensitivity, specificity and predictive accuracy of TWA for VT were 88%, 72% and 77%, respectively. Multivariate analysis showed that the presence of VT was a major independent determinant of TWA in patients with DCM (p = 0.003). CONCLUSIONS: T-wave alternans was closely related to VT in patients with DCM. T-wave alternans is a useful noninvasive test for identifying high risk patients with DCM who have VT.
Authors: K Sakabe; T Ikeda; T Sakata; A Kawase; K Kumagai; N Tezuka; M Takami; T Nakae; M Noro; Y Enjoji; K Sugi; T Yamaguchi Journal: Ann Noninvasive Electrocardiol Date: 2001-07 Impact factor: 1.468
Authors: G Turitto; E B Caref; G El-Attar; M Helal; A Mohamed; R P Pedalino; N El-Sherif Journal: Ann Noninvasive Electrocardiol Date: 2001-04 Impact factor: 1.468
Authors: Paulus Kirchhof; Lars Eckardt; Sascha Rolf; Hans-D Esperer; Matthias Paul; Thomas Wichter; Helmut U Klein; Günter Breithardt; Dirk Böcker Journal: Ann Noninvasive Electrocardiol Date: 2004-04 Impact factor: 1.468
Authors: Francesco Furlanello; Giorgio Galanti; Paolo Manetti; Andrea Capalbo; Nicola Pucci; Antonio Michelucci; Daniele Marangoni; Francesco Terrasi; Giacinto Pettinati; Riccardo Cappato Journal: Ann Noninvasive Electrocardiol Date: 2004-07 Impact factor: 1.468