Abstract 1590: Association Between Arterial Stiffness, Coronary Microcirculation And Left Ventricular Function In Patients With Newly Diagnosed Arterial Hypertension.
Arterial stiffness is an independent marker of cardiovascular morbidity and mortality. Coronary microcirculation is impaired in patients with arterial hypertension. We investigated the relationship between arterial stiffness, coronary microcirculation and left ventricular (LV) systolic and diastolic function.
METHODS: 80 untreated consecutive patients (mean age: 55±11 years 38 males), with newly diagnosed arterial hypertension and 20 healthy controls matched for sex, age and atherosclerotic factors, were studied. We measured a) Carotid to femoral artery pulse wave velocity (PWV) 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 (140 μ g/kg/min) to VTI-Vd at baseline to assess coronary flow reserve (CFR) d) E and A doppler, Em, Am mitral annulus velocities TDI and E/Em ratio to assess LV diastolic function d) Mean Longitudinal, Transverse, Circumferential and Radial Strain and Strain Rate by 2-D Strain to assess LV systolic function.
RESULTS: Patients and controls had normal ejection fraction. Compared to controls, patients with hypertension had higher PWV (10.4±1.7 vs. 8.2±1.4 m/s, p<0.001), E/Em (8.3±2.8 vs. 5.7±1.4, p=0.001) and lower CFR (2.6±0.6 vs. 3.4±0.7, p<0.001), Vd/Vs (1.78±0.31 vs. 1.97±0.38, p=0.04), DT-Vd (973±226 vs 1113±332 ms, p<0.001), Em/Am (0.93±0.42 vs. 1.6±0.51, p<0.001), mean longitudinal strain (−17.8±3 vs. −19.8±3.1%, p=0.031) and mean circumferential strain ( −19.6±4.5 vs. −22±3.4 %, p=0.04). Increasing PWV was related to increasing E/Em (r=0.26, p=0.045) and decreasing CFR (r=−0.68, p<0.001). Increasing E/Em was related to decreasing Vd/Vs (r=−0.3, p<0.005) and CFR (r=−0.32, p=0.002).
CONCLUSIONS: Patients with arterial hypertension present subclinical systolic LV dysfunction and significant LV diastolic dysfunction compared to healthy controls. Increased LV diastolic filling pressures caused by arterial stiffness may increase the resistance of myocardial microcirculation leading to impaired coronary flow