Avtor/Urednik		Žižek, David; Cvijić, Marta; Tasič, Jan; Jan, Matevž; Frljak, Sabina; Zupan, Igor
Naslov		Effect of cardiac resynchronization therapy on beat-to-beat T-wave amplitude variability
Tip		članek
Vir		Europace
Vol. in št.		Letnik 14, št. 11
Leto izdaje		2012
Obseg		str. 1646-52
Jezik		eng
Abstrakt		AimsT-wave amplitude variability (TAV) is a promising non-invasive predictor of arrhythmic events in patients with dilated cardiomyopathy. We aimed to evaluate the effect of cardiac resynchronization therapy (CRT) on native TAV, its relation with left ventricular (LV) reverse remodelling and the occurrence of ventricular tachyarrhythmias (VTs).Methods and resultsIn this prospective study, we included 40 heart failure patients with left bundle branch block in sinus rhythm (25 male; 16 with ischaemic aetiology; aged 62.7 +/- 9.5 years; New York Heart Association class II-IV). Echocardiographic parameters and TAV were evaluated at baseline and 6 months after implantation of CRT device combined with an implantable cardioverter-defibrillator. T-wave amplitude variability was determined by a 20-min high-resolution electrocardiogram Holter recording during native conduction. After TAV assessment, patients were monitored for 15.7 +/- 5.2 months for the occurrence of VTs. Decrease in median TAV [from 40.45 muV (24.75-56.00) to 28.15 muV (20.93-37.95), P = 0.004] was observed after 6 months of CRT. However, decrease of median TAV was only noticed in patients with LV reverse remodelling [46.9 muV (27.5-70.0) to 25.8 muV (20.2-32.4), P < 0.001] and in patients without VTs [40.5 muV (27.5-55.9) to 24.4 muV (17.1-31.5), P < 0.001]. Native median TAV > 35.4 microV after 6 months of CRT had an 83% sensitivity and 93% specificity for predicting the occurrence of VTs.ConclusionsDecrease of TAV after CRT is associated with LV reverse remodelling and indicates a reduction of the intrinsic arrhythmogenic substrate. Median TAV after CRT had a good predicting value for VT occurrence in long-term follow-up.
Deskriptorji		CARDIOMYOPATHY, CONGESTIVE TACHYCARDIA, VENTRICULAR DEFIBRILLATORS, IMPLANTABLE ELECTRIC COUNTERSHOCK ECHOCARDIOGRAPHY ELECTROCARDIOGRAPHY TREATMENT OUTCOME PROSPECTIVE STUDIES