Evaluation of the Delayed Disappearance of Idiopathic Premature Ventricular Beats After Unsuccessful Ablation

Radiofrequency catheter ablation (RFCA) is an effective and successful approach to the treatment of symptomatic, idiopathic premature ventricular contractions (PVCs); however, some patients experience the delayed disappearance of the arrhythmia.
 
The current prospective cohort study was conducted on 28 patients who suffered from idiopathic PVCs whose RFCA was primarily unsuccessful and who were followed up on for 6 months. Forty-six patients were examined, and 18 of them were lost to follow-up. Characteristics, including age, sex, arrhythmic foci, and left ventricular ejection fraction (LVEF) at the end of RFCA, were recorded. Additionally, 24-hour cardiac Holter monitoring was performed for the patients within 6 months after the intervention.
 
Fifteen patients (53.57%) did not respond to the treatment, while among the others, PVCs ceased within 3 and 6 months after the intervention in 11 (84.61%) and 2 (15.39%). Most PVCs originated from the LV summit (35.71%), followed by the septal part of the right ventricle (RV) (21.42%), the right ventricular outflow tract (RVOT) (14.28%), and the LVOT (7.14%). The success rate assessment revealed the best outcomes in patients with PVCs originating from the septal part of the RV (83.3%) and the RVOT (75%). There were insignificant associations between the age, sex, and the mean LVEF of patients with unsuccessful ablation therapy.
 
Ventricular arrhythmias with left-sided origins had a worse response to RFCA considering unresponsiveness or delayed arrhythmia elimination. We found no association between the age, sex, and LVEF of the patients who never experienced successful arrhythmia cessation compared with those with delayed idiopathic PVC cessation. (Iranian Heart Journal 2023; 24(4): 6-13)