Cardiac effects of chronic renal failure and haemodialysis treatment. Hypertensive versus normotensive patients.

Abstract

To investigate differences in cardiac changes between normotensive and hypertensive patients with chronic renal failure, and the effects of hemodialysis on cardiac function, 31 hypertensive and 10 normotensive patients with chronic renal failure and uremia were examined by echocardiography before and after 69 hemodialyses. There were no differences between the groups with regard to left ventricular end-diastolic size and function. In hypertensive patients, the left ventricular masses and posterior wall thicknesses were greater than in normotensive patients in response to chronically increased left ventricular afterload. In 29% of hypertensive patients, the ratio of interventricular septal to posterior wall thickness was abnormal. The left atrial diameter was also greater in the hypertensive group as a response to decreased left ventricular compliance. In all the patients hemodialysis caused a significant decrease in body weight and diastolic blood pressure. The left atrial diameter and left ventricular end-diastolic diameter decreased obviously as a response to decreased ventricular filling pressure because of decreased blood volume, but the cardiac index did not decrease significantly. The differences in cardiac changes caused by hemodialysis between hypertensive and normotensive patients were very small; the left atrial decreased significantly only in hypertensive patients and heart rate increased only in normotensive patients. In chronic renal failure, left ventricular hypertrophy is principally caused by arterial hypertension and left ventricular dilatation by factors such as increased blood volume and cardiac output. Hemodialysis principally causes a decrease in left ventricular diastolic volume and less decrease in cardiac output. Hypertensive and normotensive patients seem to be similarly susceptible to the hemodynamic effects of hemodialysis.