In patients receiving right ventricular pacing leads, the incidence of pacing-induced cardiomyopathy was similar between those with moderate pre-implant LVEF and preserved LVEF (31.25% vs 28%, p=0.786).
Cohort (n=145)
Does baseline LVEF or other clinical factors predict the incidence of pacing-induced cardiomyopathy in patients receiving right ventricular pacing for symptomatic bradycardia?
The incidence of pacing-induced cardiomyopathy is similar in patients with preserved and moderately reduced baseline LVEF, and is predicted by longer pre-implant QRS duration, higher pacing burden, diabetes, atrial fibrillation, and prior smoking.
Absolute Event Rate: 31.25% vs 28%
p-value: p=0.786
Abstract Background PICM is correlated with a high morbidity with an increase in hospitalisations and mortality. There is limited evidence to guide risk prediction of PICM, particularly in patients who had moderate LVEF 35-49% prior to implant. There is an unmet clinical need to understand of the prevalence and incidence of PICM in individuals with pacing devices and the contributory factors. Methods Retrospective review of patients with right ventricular pacing leads for symptomatic bradycardia, who developed PICM versus patients who did not. PICM was defined as 10% reduction in left ventricular ejection fraction reduction since pre-pacemaker implantation echocardiogram. Continuous variables in both groups were compared with multivariate logistic regression test and categorical variables were compared using the Chi-square test. A p-value of less than 0.05 was considered as statistically significant. Data was analysed with Stata 18. Results 245 patients who received treatment at between June 2021 and May 2024 were screened and 145 patients fulfilled inclusion criteria. The mean age was ±72 years 50% at baseline (31.25% (n= 30) vs 28% (n=5), p 0.786). The incidence of PICM according to RV pacing site was RV apex 62.16%, RV septal 37.84%, p 0.354 in all patients and RV apex 41,67 % and RV septal 58.33%, p 0.49 with moderate LVEF prior to implant. Pre implant QRS duration was significantly different between both groups (94ms vs 134 ms, p 0.0006, Table 1) and was associated with a higher risk of PICM (OR 1.11, p 0.02) as was smoking, diabetes and AF. For every 1% increase in pacing burden the odds of PICM rose by 1.6% (p 0.0001). A longer paced QRS was significantly correlated with PICM. Conclusion PICM was common in this patient cohort occurring in 28% of patients with a pre implant LVEF 50%. Predictors of PICM included longer pre implant QRS duration, higher pacing percentage. New predictors were the presence of diabetes, atrial fibrillation and prior smoking. No difference in PICM was found in preserved and moderately reduced LVEF independent of RV pacing site. Future studies will show if prevention or treatment of these risk factors can reduce the incidence of PICM, especially in the case of physiological pacing which is associated with QRS reduction.Table 1&2Figure 1
Howell et al. (Mon,) conducted a cohort in Symptomatic bradycardia requiring right ventricular pacing (n=145). Moderate LVEF (35-49%) prior to implant vs. Preserved LVEF (>50%) prior to implant was evaluated on Incidence of pacing-induced cardiomyopathy (>10% reduction in LVEF since pre-pacemaker implantation) (p=0.786). In patients receiving right ventricular pacing leads, the incidence of pacing-induced cardiomyopathy was similar between those with moderate pre-implant LVEF and preserved LVEF (31.25% vs 28%, p=0.786).