098 Differential effects of hypertrophy secondary to hypertension and aortic stenosis on coronary haemodynamics

It is known that subjects with left ventricular hypertrophy (LVH) have adverse cardiovascular outcomes and abnormal coronary haemodynamics. LVH is common to aortic stenosis (AS) and arterial hypertension (HT) but the pattern of abnormal coronary flow may be different in these two conditions. The aim of this study was to quantify the coronary haemodynamics present in each of these conditions and determine the relative contribution of LVH, haemodynamic loading and diastolic time. Thirty-one patients (mean age 63±12 years, 18 female) with unobstructed coronary arteries, (10 with LVH and severe AS, 11 with LVH secondary to HT and no AS (LVH-HT), 10 with no LVH and no AS) underwent simultaneous pressure and Doppler velocity measurements with sensor-tipped intra-arterial wires in each of the left coronary arteries to measure coronary pressure and flow and derive wave intensity. Despite the lower aortic pressure (93±18 mm Hg vs 115±15, p 3 Wm −2 s −1 vs 12.2 (8.4–17.5)×10 3 Wm −2  s −1 , p LVH accounts for the impaired coronary flow in HT but not in AS. The enhanced extravascular force in AS overwhelms any local impairment that might be caused by ventricular hypertrophy and accounts for the greatly increased resting coronary flow.