Inclusion Criteria:  Age >18, <80 of age Symptomatic PVCs refractory to ≥1 antiarrhythmic drugs (including β-blockers and calcium-channel blockers). PVC burden ≥ 10%, with or without prior ablation Arrhythmias originated from any focus (foci) in the right ventricular or left ventricular.  Exclusion Criteria:  Left ventricular ejection fraction (LVEF) < 45% unless proven to be PVC-mediated cardiomyopathy (history of improving LVEF by >15% when PVC burden was reduced by pharmacological agents or ablation) EF continues to decrease in the past 4 months regardless of the etiology Unwilling to continue current pharmacological therapy during the study period Severe heart failure with New York Heart Association Class ≥ III Ventricular arrhythmias attributed to underlying structural heart disease, known myocardial scar or myocarditis Change of anti-arrhythmic drug dosing, including β-blockers and calcium channel blockers, within 2 months prior to enrollment < 3 months after prior unsuccessful ablation: Patients on amiodarone Patients with known thyroid issues, on renal-dialysis life expectancy of < 12 months Sustained ventricular tachycardia