Effect of transcatheter aortic valve implantation on QT dispersion in patients with aortic stenosis.

Background: QT dispersion (QTd) is a predictor of ventricular arrhythmia. Ventricular arrhythmia is an important factor influencing morbidity and mortality in patients with aortic stenosis. Surgical aortic valve replacement reduced the QTd in this patients group. However, the effect of transcatheter aortic valve implantation (TAVI) on QTd in patients with aortic stenosis is unknown. The aim of this study was to investigate the effect of TAVI on QTd in patients with aortic stenosis.

Methods: Patients with severe aortic stenosis, who were not candidates for surgical aortic valve replacement due to contraindications or high surgical risk, were included in the study. All patients underwent electrocardiographic and echocardiographic evaluation before, and at the 6(th) month after TAVI, computed QTd and left ventricular mass index (LVMI).

Results: A total 30 patients were admitted to the study (mean age 83.2 ± 1.0 years, female 21 and male 9, mean valve area 0.7 ± 3 mm(2)). Edwards SAPIEN heart valves, 23 mm (21 patients) and 26 mm (9 patients), by the transfemoral approach were used in the TAVI procedures. All TAVI procedures were successful. Both QTd and LVMI at the 6(th) month after TAVI were significantly reduced compared with baseline values of QTd and LVMI before TAVI (73.8 ± 4 ms vs. 68 ± 2 ms, P = 0.001 and 198 ± 51 g/m(2) vs. 184 ± 40 g/m(2), P = 0.04, respectively). There was a significant correlation between QTd and LVMI (r = 0.646, P < 0.001).

Conclusions: QTd, which malign ventricular arrhythmia marker, and LVMI were significantly reduced after TAVI procedure. TAVI may decrease the possibility of ventricular arrhythmia in patients with aortic stenosis.