Reduction in coronary and peripheral vasomotor function in patients with HIV after initiation of antiretroviral therapy: a longitudinal study with positron emission tomography and flow-mediated dilation.

ABSTRACT

OBJECTIVES: The mechanisms underlying the increased cardiovascular risk in patients with HIV on antiretroviral therapy (ART) are not known. Our aim was to study the endothelial function of the coronary arteries by cardiac perfusion positron emission tomography (PET) in patients with HIV initiating ART. In addition, flow-mediated dilation (FMD) of the brachial artery was measured. METHODS: Patients with HIV scheduled to initiate ART (n=12) were included. NH3 perfusion PET and FMD scans were performed both before and 5 weeks (24-67 days) after initiation of ART. Data were compared with paired t-tests and a P value of less than 0.05 was considered significant. RESULTS: No changes were found in the pulse-pressure-corrected myocardial rest perfusion (1.22+/-0.07-1.09+/-0.05 ml/min/g tissue, NS) or cold pressor reserve (1.18+/-0.08-1.27+/-0.05, NS). However, the maximal myocardial perfusion decreased 31% from 2.50+/-0.25 to 1.73+/-0.15 ml/min/g tissue (P=0.009) and the myocardial perfusion reserve decreased 20% from 3.11+/-0.32 to 2.48+/-0.25 (P=0.042). FMD decreased from 8.68+/-1.70 to 4.58+/-0.93% (P=0.027). No change was observed in nitroglycerin-mediated dilation (12.8+/-1.0-14.4+/-1.4%, NS). CONCLUSION: In patients with HIV initiating ART, signs of development of endothelial dysfunction assessed by coronary perfusion PET and FMD were found early after starting medication.