Influence of chronic renal insufficiency on left ventricular diastolic function in hypertensives without left ventricular hypertrophy

Background. Patients with chronic renal insufficiency (CRI) have a much greater cardiovascular risk than the general population. Moreover, hypertension is common in these patients, as is left ventricular hypertrophy (LVH) and diastolic dysfunction, which contribute to a worse prognosis. While these findings are well established for end-stage renal disease, fewer data are available in mild to moderate CRI. Furthermore, little is known about diastolic function in CRI patients without LVH. Methods. We performed a cross-sectional study to evaluate LV structure and function in hypertensives with CRI, compared with hypertensives with normal renal function (EH), by means of mitral inflow and tissue Doppler echocardiography. Patients with LVH were excluded from both groups. Results. CRI patients had higher left ventricular end-diastolic diameter, end-systolic diameter (p<0.0001 and p=0.0001, respectively) and left ventricular mass index (LVMI) (p<0.0001) than EH patients. The CRI group also showed greater alterations of the diastolic function indexes than hypertensives: lower E-wave peak velocity (p=0.02), E-wave peak velocity to A-wave peak velocity ratio (p=0.03) and early diastolic myocardial velocity (p=0.04), higher A-wave peak velocity (p=0.07), E-deceleration time (p=0.02) and isovolumic relaxation time (p=0.0001). Multiple regression analysis demonstrated that renal function was a predictor of LVMI and diastolic function independently of age, sex, pulse pressure, body mass index and duration of hypertension. Conclusions. Our data showed a greater alteration of diastolic function in the CRI group, in part independent of LVMI. In CRI, factors other than LVMI and blood pressure seem to play an important role in causing early diastolic dysfunction.