Purpose: To assess the predictive value of single PVCs 1 month after CRT implantation to the mid-term clinical response and long-term all-cause mortality
Methods: In our prospective, single-center study, 125 symptomatic heart failure (HF) patients (NYHA II-IVa) with reduced left ventricular ejection fraction (EF =35%) and wide QRS (=120ms) underwent CRT implantation and were followed for 2 years. The primary endpoint was all-cause mortality, the secondary endpoints were echocardiographic reverse remodelling assessed by =15% improvement in EF, left ventricular end-systolic volume (ESV) or left atrial volume (LAV) after 6 months. The number of PVCs were assessed by device interrogation at 1 month after CRT implantation.
Results: During the mean time of follow up (2.2 years) 26 patients died and reached the primary endpoint. Those 67 patients who attended 1 month follow up, median number of PVCs was 11401. Patients with higher number of PVCs than this median showed a higher risk of all-cause mortality (p=0.034), which was also confirmed by multivariate analysis (HR: 3.00; 95% CI: 1.34-6.74; p=0.01) as an independent predictor after adjusting for left bundle branch block. When secondary endpoints were investigated, patients with less PVCs than the median had a 4.8 times higher odds for developing LAV reverse remodelling 6 months after CRT implantation.
Conclusions: In patients underwent CRT implantation, greater amount of PVCs are associated with higher all-cause mortality and predicts atrial remodelling. Our results are pointing at the importance of PVCs as a response marker and warrant further investigations.