Morbidity and mortality due to hypertension in patients with renal failure.

The incidence of, and the mortality from, cardiac disease is strikingly increased in dialysis patients. Coronary disease existing prior to the onset of dialysis is an important determinant of ischemic heart disease (IHD) on dialysis. Death from IHD on dialysis is higher by factor 5-20 than in the general population. In several studies either a marginal or no relation between blood pressure on admission to renal replacement therapy, or average predialysis blood pressure and cardiac death has been noted. In other studies blood pressure was, however, predictive of IHD. Such discrepancies may be explained by a low-risk threshold, a nonlinear relationship, and the necessity to examine large patient cohorts to document the effect. Of great importance may be the potentially increased susceptibility of the heart to hypertensive injury and ischemia. This may be related to factors like left ventricular hypertrophy, cardiac fibrosis and altered cardiac mechanical properties, diminished coronary reserve, and reduced ischemia tolerance, particularly during intradialytic hypotensive episodes due to compromised microcirculation and disturbed insulin-induced glucose uptake and abnormalities of autonomous neural innervation of the heart.