Abstract 2687: Arterial Stiffness Determines Baseline Coronary Flow And Flow Reserve In Untreated Patients With Arterial Hypertension
Arterial stiffness is a marker of subclinical atherosclerosis with prognostic significance. Coronary microcirculation is disturbed in patients with arterial hypertension. We investigated whether the arterial stiffness may determine baseline coronary flow and flow reserve (CFR) in never-treated hypertensives.
METHODS: We studied 100 untreated consecutive patients (mean age: 55±11 years 53 male and 47 females), with newly diagnosed arterial hypertension and 20 controls matched for sex, age and atherosclerotic factors, Exclusion criteria were history of diabetes, familiar hyperlipidemia, CAD, cardiomyopathy and chronic obstructive pulmonary disease. We measured a) Carotid to femoral artery pulse wave velocity (PWV) as an estimate of arterial stiffness using the Complior apparatus b) Peak Systolic (Vs) and diastolic (Vd) coronary blood flow velocity , Vd/Vs ratio, Deceleration Time (DT-Vd) and time integral (VTI-Vd) of Vd using a 7MHZ transducer by means of colour-guided Doppler echocardiography at the distal tract of the LAD c) Ratio of VTI-Vd after adenosine infusion (140μg/kg/min) to VTI-Vd at baseline to assess coronary flow reserve (CFR)
RESULTS: All patients had normal LVmass (men<134gr/m2, women <110gr/m2) and had higher PWV (10.4±1.7 vs. 8.2±1.4 m/s, p<0.001) and lower CFR, Vd/Vs and DT-Vd (2.6±0.6 vs 3.4±0.7, p<0.001, 1.78±0.31 vs. 1.97±0.38, p=0.04 and 973±226 vs. 1113±332 ms, p<0.001 respectively) than controls. Increasing PWV was related to decreasing Vd/Vs (r=-0.65, p<0.001) , DT-Vd (r=-0.8, p<0.001), CFR (r=-0.7, p<0.001) and VTI-Vd post adenosine (r=-0.24, p=0.034). In multivariate regression analysis, PWV and smoking were the most important determinants of CFR among age, sex, body mass index, mean blood pressure and hyperlipidemia (b: - 2.21, p<0.001 and b: - 2.68, p=0.032 respectively). Patients with CFR>2 had significantly lower PWV, than those with CFR<2 (n=20) (10±1.5 vs. 12±2 m/s p<0.001). By ROC analysis, a PWV>10.7 m/sec predicted a CFR < 2 with a 84% and 80% sensitivity and specificity respectively.
CONCLUSIONS: Arterial stiffness determines with baseline coronary flow and flow reserve in never treated hypertensives with no evidence of LV hypertrophy.