%0 Journal Article %@ 0008-4212 %A Orosz Andrea %A Baczkó István %A Nagy Viktória %A Gavallér Edit Henriette %A Csanády Miklós %A Forster Tamás %A Papp Gyula %A Varró András %A Lengyel Csaba Attila %A Sepp Róbert %D 2015 %F publicatio:11594 %J CANADIAN JOURNAL OF PHYSIOLOGY AND PHARMACOLOGY %N 9 %P 765-772 %T Short-term beat-to-beat variability of the QT interval is increased and correlates with parameters of left ventricular hypertrophy in patients with hypertrophic cardiomyopathy %U http://publicatio.bibl.u-szeged.hu/11594/ %V 93 %X Stratification models for the prediction of sudden cardiac death (SCD) are inappropriate in patients with hypertrophic cardiomyopathy (HCM). We investigated conventional electrocardiogram (ECG) repolarization parameters and the beat-to-beat short-term QT interval variability (QT-STV), a new parameter of proarrhythmic risk, in 37 patients with HCM (21 males, average age 48 +/- 15 years). Resting ECGs were recorded for 5 min and the frequency corrected QT interval (QTc), QT dispersion (QTd), beat-to-beat short-term variability of QT interval (QT-STV), and the duration of terminal part of T waves (Tpeak-Tend) were calculated. While all repolarization parameters were significantly increased in patients with HCM compared with the controls (QTc, 488 +/- 61 vs. 434 +/- 23 ms, p < 0.0001; QT-STV, 4.5 +/- 2 vs. 3.2 +/- 1 ms, p = 0.0002; Tpeak-Tend duration, 107 +/- 27 vs. 91 +/- 10 ms, p = 0.0015; QTd, 47 +/- 17 vs. 34 +/- 9 ms, p = 0.0002), QT-STV had the highest relative increase (+41%). QT-STV also showed the best correlation with indices of left ventricular (LV) hypertrophy, i.e., maximal LV wall thickness normalized for body surface area (BSA; r = 0.461, p = 0.004) or LV mass (determined by cardiac magnetic resonance imaging) normalized for BSA (r = 0.455, p = 0.015). In summary, beat-to-beat QT-STV showed the most marked increase in patients with HCM and may represent a novel marker that merits further testing for increased SCD risk in HCM. %Z FELTÖLTŐ: Bernátskyné Babus Csilla - csbabus@ek.szte.hu