Electrocardiographic changes in HIV-infected, drug-experienced patients being treated with atazanavir.

The QRS interval of 56 out of 75 (74.7%) HIV-infected, drug-experienced patients (66.7% men) increased during treatment with boosted or unboosted atazanavir by a median 5 ms (interquartile range 0-9; P < 0.0001); the PR and the QTc intervals did not change significantly. New asymptomatic bundle branch blocks were observed in four patients; one subject with a baseline first-degree atrioventricular block developed symptomatic bradyarrhythmia while receiving atenolol. The electrocardiographic monitoring of patients treated with atazanavir seems advisable.