Cardiovascular highlights from non-cardiology journals

Azithromycin and cardiac death

Macrolide antibiotics are associated with prolongation of the QT interval in susceptible individuals and increase the risk of serious ventricular arrhythmias and sudden cardiac death. Azithromycin has become one of the most widely used macrolides worldwide due to its broad spectrum, excellent tissue penetrance and long half-life, and has been reported to be minimally cardiotoxic. However, several case reports have been published associating azithromycin with polymorphic ventricular tachycardia suggesting this may not be the case. In this large retrospective cohort study, Ray et al utilised data from a Medicaid cohort collating information on patients who took azithromycin (347 795 prescriptions), propensity-score-matched persons who took no antibiotics (1 391 180 control periods), and patients who took amoxicillin (1 348 672 prescriptions), ciprofloxacin (264 626 prescriptions), or levofloxacin (193 906 prescriptions). During 5 days of therapy, patients taking azithromycin, as compared with those who took no antibiotics, had an increased risk of cardiovascular death (HR, 2.88; 95% CI 1.79 to 4.63; p<0.001) and death from any cause (HR, 1.85; 95% CI 1.25 to 2.75; p=0.002). Patients who took amoxicillin had no increase in the risk of death during this period. Relative to amoxicillin, azithromycin was associated with an increased risk of cardiovascular death (HR, 2.49; 95% CI 1.38 to 4.50; p=0.002) and death from …