Remzi KARAOĞUZ, Fatih Sinan ERTAŞ, Muharrem GÜLDAL, Güneş AKGÜN, Ömer AKYÜREK, Yusuf ATMACA, Çağdaş ÖZDÖL, Timuçin ALTIN, Çetin EROL

Dispersion of QT interval in premature ventricular beats in not an independent marker for inducible sustained ventricular tachycardia

Amaç: 12 derivasyonlu EKG nin farklı derivasyonları arasında QT interval süresinde değişkenlik birçok klinik durumda ventriküler aritmiler için bir risk göstergesi olarak öngörülürken, QTd-V nin değeri henüz açık değildir. Çalışmanın amacı reentran ventriküler takiaritmilere (VT) duyarlılığı olan hastaları belirlemede ventriküler premature atımlarda QT dispersiyonu'nun (QTd-V) değerini araştırmaktır. Gereç ve Yöntem: Elektrofizyolojik çalışma yapılmış 34 hastada indüklenebilir VT nin tahmini için prekordiyal QTd-V, sinyal ortalamalı EKG de geç potansiyeller ve azalmış sol ventrikül ejeksiyon fraksiyonu karşılaştırıldı. Bulgular: İndüklenebilir VT li 12 hastadaki QTd-V (110±50 msec) VT nin indüklenemediği 22 hastadaki QTd-V den (65±38 msec, p=0.006) daha büyük bulundu. Ejeksiyon fraksiyonu ve geç potansiyel varlığının dahil edildiği çok değişkenli analiz QTd-V nin ventriküler takiaritmilere duyarlı hastaları belirlemede bağımsız bir faktör olmadığını gösterdi. Sonuç: Artmış QTd-V tek başına reentran ventriküler takiaritmilere duyarlılıkla ilintili olsa da, geç potansiyeller ve sol ventrikül ejeksiyon fraksiyonu hesaba katıldığında ilave tanısal bilgi sağlamadığı gözükmektedir.

Ventriküler prematüre atımların QT interval dispersiyonu indüklenebilir sürekli ventriküler taşikardi için bağımsız bir gösterge değildir

Aim: Variability in QT interval duration on the different leads of the 12-lead ECG has been proposed as an indicator of risk for ventricular arrhythmias in different clinical settings, but the value of QTd-V is not clear yet. The aim of this study was to estimate the value of QT dispersion in ventricular premature beats (QTd-V) in identifying patients susceptible to reentrant ventricular tachyarrhythmias (VT). Materials and Methods: We compared the performance of precordial QTd-V, late potentials on the signal-averaged electrocardiogram and reduced left ventricular ejection fraction for identification of inducible ventricular tachycardia in 34 patients undergoing electrophysiologic study. Results: QTd-V in 12 patients with inducible VT (110±50 msec) was found to be greater than that in 22 patients without inducible VT (65±38 msec, p=0.006). Multivariate analysis including ejection fraction and presence of late potentials showed that QTd-V was not an independent factor in identifying the susceptible patients to ventricular tachyarrhythmias. Conclusion: Increased QTd-V is related to susceptibility to reentrant ventricular tachyarrhythmias, however does not appear to provide additional diagnostic information to that provided by late potentials and left ventricular ejection fraction.

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