Compared to the referent group, recipients treated with other immunosuppression+HCQ had a 2-fold increased risk of abnormal ECG or QT prolongation (18.9% vs. 10.7%; aHR,1.12 1.963.42 , p=0.02) and ventricular arrhythmias (15.2% vs. 11.4%; aHR,1.00 1.813.29 , p=0.05) in the >1-to-3 years posttransplant.