Shen L, et al. - In patients with heart failure with preserved ejection fraction (HFpEF), researchers assessed the link between prior pacemaker implantation and clinical outcomes, including the risk of the primary composite of cardiovascular death or HF hospitalization, the individual components of the composite, the two main modes of cardiovascular death (ie, sudden death and pump failure death), and all-cause death. They pooled patient data from three studies. Compared with patients without pacemakers, those with pacemakers had almost twice rate of the primary composite outcome, with similar finding for HF hospitalizations. In the adjusted analyses, no significantly higher mortality risk was noted in patients with pacemakers. Based on these findings, a possible detrimental impact of right ventricular pacing-induced left ventricular dyssynchrony in patients with HFpEF was suggested.