Right ventricular subclinical dysfunction in high-burden idiopathic outflow tract premature ventricular contraction population.

Background: The relationship between premature ventricular contractions (PVC) and right ventricular (RV) function is not widely known. Left ventricular (LV) dysfunction due to PVC is known as PVC-induced cardiomyopathy (PIC) and suppressing the PVC substrate would improve LV function. The effect of PVC ablation on changes in RV function in patients with subtle RV subclinical dysfunction remains unknown.

Objective: Understanding the alterations in RV function parameters after PVC ablation.

Method: Basic and speckle-tracking echocardiography has been performed on 42 individuals with symptomatic idiopathic outflow tract PVC before and 1 month after a successful ablation.

Result: At the baseline of the study, there were 26 patients with RV subclinical dysfunction and 16 patients without RV dysfunction. Patients with RV subclinical dysfunction exhibited significantly higher PVC burden and QRS complex duration than those with normal RV function (p < 0.05). A PVC burden ≥ 21% (OR 9.11, 1.54-53.87, p = 0.015) and a QRS complex duration ≥ 138 ms (OR 5.74, 1.07-30.90, p = 0.042) were independently associated with RV subclinical dysfunction. In both groups, measurements of RV subclinical function before and after ablation, specifically by free wall longitudinal strain (FWLS) and global longitudinal strain (GLS), demonstrated significant changes. These improvements were more pronounced in the group with RV dysfunction (FWLS 9.7 ± 4.0, p < 0.001; GLS 7.5 ± 4.2, p < 0.001). Lower initial FWLS and GLS before ablation emerged as significant parameters in the multivariate analysis for the improvement of RV function post-ablation.

Conclusion: Patients with RV subclinical dysfunction had higher PVC burden and wider QRS duration. Patients with idiopathic outflow tract PVC with RV subclinical dysfunction may experience improvements in RV function after successful PVC ablation.