Premature ventricular complex site of origin and ablation outcomes in patients with diabetes mellitus.

Background: Premature ventricular complexes (PVCs) are frequent in patients with diabetes mellitus (DM). Still, the PVCs characteristics as well as the outcomes after catheter ablation in this population remain unknown. Aim of the study was to describe principal features of PVCs ablated in a wide DM-patients cohort and report postablation clinical outcomes in the follow-up of patients with DM and left ventricular dysfunction.

Methods: From April 2012 to April 2020 data of 544 patients (315 [58%] men, 55±16 y), consecutive patients submitted for PVC ablation, were prospectively collected. Patients with left ventricle (LV) systolic disfunction (LVEF<50%) were included in a prospective protocol and followed at 6 and 12 months, and annually thereafter. Baseline characteristic as well ablation outcomes were analyzed based on the presence of DM.

Results: Sixty (11%) patients had DM. Patients with DM more frequently had a PVC's site of origin (SOO) in the LV (45 [75%] vs. 229 [48%], P<0.001). The most frequent PVC's SOO in DM patients was the LV outflow tract (OT) (35 [58%] patients: 12 aortic cusps; 12 LV summit; 11 in the myocardium immediately inferior to the valvular plane). Fifty-five (92%) patients with DM had an acute successful ablation, without differences compared with patients without DM (55 [92%] vs. 437 [90%], P=0.9). Twenty-tree (38%) DM-patients had LV dysfunction at the ablation time. In these patients, mean PVC burden decreased from 26±11% at baseline to 4±5% (P<0.001); LVEF increased from 36±8% to 42±11% (P<0.01) and NYHA class improved from 2.2±0.6 to 1.8+0.5 (P<0.01), after a mean follow-up of 37±14 months.

Conclusions: Patients with DM frequently have PVC with a LV-SOO, being the LVOT the most frequent SOO in this population. Among DM patients with LV dysfunction, ablation persistently and significantly reduce the PVC burden improving functional status. Patients with DM have lower benefit in terms of LV function recovery after ablation compared with non-diabetic patients.