Prevalence and incidence of left ventricular systolic dysfunction and adverse outcomes in patients receiving de novo and replacement pacemaker therapy for bradycardia.

Abstract

Aims: Right ventricular pacing (RVP) is associated with left ventricular systolic dysfunction (LVSD) and heart failure (HF). We investigated the prevalence and predictors of LVSD and adverse HF outcomes in patients undergoing de novo or replacement RVP for bradycardia.

Methods and results: Prospective data were collected from 1024 patients receiving de novo (2014-2017, n = 514) or generator replacement (2008-2011, n = 510) RVP at a UK tertiary centre. Logistic regression models were used to identify predictors of LVSD, defined as left ventricular ejection fraction (LVEF) < 50%, and subsequent HF hospitalization (HFH) and all-cause mortality. Overall, 61% were male; mean age 76 +/- 11 years. De novo patients were more often male (66% vs. 56%) and more likely to have ischaemic heart disease (IHD; 31% vs. 14%) and diabetes (24% vs. 6%), but less likely to have atrial fibrillation (AF; 25% vs. 33%) than replacement patients (all P < 0.01). LVSD was present in 344 (37%) and was more frequent in de novo than replacement cases (20% vs. 17%, P < 0.01). Independent predictors of LVSD were IHD [odds ratio (OR) = 2.56, confidence interval (CI): 1.58-4.13] and ventricular pacing burden >80% (OR = 2.13, CI: 1.29-3.52). Over a median 30 (IQR: 16-42) months, 341 (33%) experienced HFH or death, more commonly after replacement than de novo RVP (25% vs. 8%, P < 0.01). Predictors of adverse outcomes included replacement status [hazard ratio (HR) = 2.27, CI: 1.78-4.16], older age, AF, and LVEF <50%.

Conclusion: LVSD is common in RVP recipients and largely driven by comorbidities rather than pacing burden. Screening and targeted therapy in high-risk patients may improve outcomes and optimize resource use.