Objective: Hyperuricemia (HU) is a well-recognized risk factor for cardiovascular diseases. The independence of this association from other confounding factors has remained controversial. The possible contributory effect of HU to myocardial impairment produced by hypertension (HT), however, has not been clarified yet. The study was designed to assess the left ventricular (LV) systolic and diastolic function in patients with HT with or without HU. Tissue Doppler imaging (TDI) was used for detailed analysis as this method was superior to other conventional echocardiographic techniques.
Methods: The study participants consisted of 27 patients (men 56%, mean age+/-SD; 55+/-10 years) with HT without HU, and 27 patients with HT with HU (men 62%, mean age+/-SD; 56+/-9 years), and 27 age-matched healthy control participants (men 57%, mean age+/-SD; 53+/-11 years). Cardiac functions were determined using echocardiography, comprising standard two-dimensional and conventional Doppler and TDI. Peak systolic myocardial velocity at mitral annulus (Sm), mitral inflow velocities and early diastolic mitral annular velocity (Em), late diastolic mitral annular velocity (Am), peak systolic mitral annular velocity, Em/Am, and myocardial performance index were calculated by TDI.
Results: Mitral inflow velocities and tissue Doppler-derived mitral annular diastolic velocities were significantly different in the patient groups (HT without HU and HT with HU) compared with the control cases. Tissue Doppler-derived myocardial performance index (LV-MPI) was significantly impaired in the patient groups compared with those of the control's (0.48+/-0.09, 0.53+/-0.07, and 0.39+/-0.07, respectively, P<0.001). Significant differences were also observed between the patients who had HT without HU and the patients who had HT with HU regarding LV-MPI. Significant correlations were observed between the serum uric acid levels and LV function parameters.