Abstract 18215: Coronary Flow Velocity Reserve and Aortic Regurgitation Index Before and After Transcatheter Aortic Valve Implantation for Severe Aortic Stenosis

Objective: Coronary flow reserve (CFR) is reduced in aortic stenosis due to altered coronary blood flow dynamics related to reduce coronary perfusion pressure and myocardial supply-demand ratio. We sought to investigate effect of Transcatheter Aortic Valve Implantation (TAVI) on CFR and its relationship to aortic regurgitation index (ARI), a marker of coronary perfusion gradient. Methods: Ten patients undergoing TAVI were enrolled and underwent invasive hemodynamic assessment, including CFR, immediately pre-TAVI, post-TAVI and at 6 to 12 months follow-up. CFR was recorded with intracoronary Doppler probe-tipped coronary flow wire as a ratio of average peak velocity, pre and post induction of maximal coronary microvascular hyperaemia with administration of intracoronary adenosine. The coronary perfusion pressure (diastolic aorta pressure minus LVEDP) was calculated over several cardiac cycles and adjusted for the systolic blood pressure to calculate the ARI. Results: 8 of the 10 patients had late follow-up...