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Background@#The long-term predicted value of microvolt T-wave alternans (MTWA) for ventricular tachyarrhythmia in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) remains unclear. Our study explored the characteristics of MTWA and its prognostic value when combined with an electrophysiologic study (EPS) in patients with ARVC.@*Methods@#All patients underwent non-invasive MTWA examination with modified moving average (MMA) analysis and an EPS. A positive event was defined as the first occurrence of sudden cardiac death, documented sustained ventricular tachycardia (VT), ventricular fibrillation, or the administration of appropriate implantable cardioverter defibrillator therapy including shock or antitachycardia pacing.@*Results@#Thirty-five patients with ARVC (age 38.6 ± 11.0 years; 28 males) with preserved left ventricular (LV) function were recruited. The maximal TWA value (MaxValt) was 17.0 (11.0–27.0) μV. Sustained VT was induced in 22 patients by the EPS. During a median follow-up of 99.9 ± 7.7 months, 15 patients had positive clinical events. When inducible VT was combined with the MaxValt, the area under the curve improved from 0.739 to 0.797. The receiver operating characteristic curve showed that a MaxValt of 23.5 μV was the optimal cutoff value to identify positive events. The multivariate Cox regression model for survival showed that MTWA (MaxValt, hazard ratio [HR], 1.06; 95% confidence interval [CI], 1.01–1.11; P = 0.01) and inducible VT (HR, 5.98; 95% CI, 1.33–26.8; P = 0.01) independently predicted positive events in patients with ARVC.@*Conclusions@#MTWA assessment with MMA analysis complemented by an EPS might provide improved prognostic ability in patients with ARVC with preserved LV function during long-term follow-up.
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ObjectivesTo assess the cardiovascular function in obese children.MethodsA total of 30 obese children and 50 age- and sex-matched normal weight children were enrolled and treadmill test was performed. Exercise tolerance, the time to target heart rate and continuous T-wave alternans (TWA) during treadmill test were compared between two groups. ResultsCompared with normal weight children, the exercise tolerance was decreased and the time to target heart rate was shortened, while the incidence of continuous TWA was increased in obese children and there was signiifcant difference between two groups (P<0.01).ConclusionsObesity may lead to cardiovascular dysfunction in childhood which should be concerned.
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Objective To explore the characteristics of T wave alternans (TWA) in aortic stenosis (AS) in school-aged children. Methods TWA was analyzed in 15 AS patients and 60 age-matched normal children using Microvolt T-Wave Alternans and the incidence of sustained TWA was compared between two groups. Myocardial ischemia during treadmill test was studied in sustained TWA and non-sustained TWA in AS patients. Results Compared with normal children, the incidence of sustained TWA was signiifcantly increased in AS group (P<0.01). In AS school-aged patients, the incidence of myocardial ischemia is higher in sustained TWA than in non-sustained TWA during treadmill test (P<0.05). Conclusions AS school-aged children have electrophysiologic basis for sunstained TWA. TWA is closely related to myocardial ischemia during treadmill test. Sustained TWA could be used as an important electrophysiologic index to assess the cardiac function in children with AS.
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Objective To explore the value of T wave alternans (TWA) in prediction ventricular arrhythmias in post-op TOF children. Methods The characteristics of TWA were retrospectively analyzed in 36 post-op TOF patients and 120 age-matched normal children. The relationship of sustained TWA and ventricular arrhythmias was also analysed. Results Compared with normal children, the incidence of sustained TWA was significantly increased in post-op TOF group (χ2=6.98, P<0.05). In post-op TOF patients, the incidence of ventricular arrhythmia was much higher when sustained TWA was present (χ2=10.41, P<0.05). Conclusions There exists electrophysiological basis for ventricular arrhythmia in post-op TOF children. Sustained TWA has important value in prediction of ventricular arrhythmia of post-op TOF.
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1.9?V and 95% confidence interval was 1.52-2.41?V.There was significant differences among the groups(P