Aims: The aim of this study was to investigate the predictive ability of paced QRS duration (pQRSd) for heart failure events among patients receiving right ventricular apical pacing (RVAP).
Methods and results: A total of 194 patients with complete atrioventricular block receiving pacemaker treatment were enrolled and stratified to group 1, pQRSd < 160 ms, n = 53; group 2, 160 ≤ pQRSd < 190 ms, n = 97; and group 3, pQRSd ≥ 190 ms, n = 44. Study outcomes were heart failure events, changes in pQRSd, and changes in left ventricular ejection fraction (LVEF). During the 3-year follow-up, the incidence of heart failure events was 9.4, 27.8, and 56.8% in groups 1, 2, and 3, respectively (P < 0.001). Among the patients without heart failure events, the pQRSd at 3 years remained longer than that at baseline (162.1 ± 22.6 vs. 160.9 ± 22.1 ms, P < 0.05), whereas among patients who experienced heart failure events, the prolonged pQRSd at 3 years seemed more pronounced as compared with baseline (184.1 ± 21.1 vs. 179.8 ± 21 ms, P < 0.001). Linear regression demonstrated that a decrease in LVEF was positively correlated with pQRSd over time (relative risk 0.423; P < 0.05). The receiver operating charactersitic curve showed that the cut-off value of pQRSd was 165 ms with a sensitivity of 0.789.
Conclusion: A prolonged pQRSd has a detrimental effect on long-term cardiac function during RVAP in patients with complete atrioventricular block. pQRSd could be a useful predictor to identify patients who are at risk for heart failure events during RVAP.