[Carotid ultrasound: prevention of heart disease and mortality on haemodialysis].

INTRODUCTION: Cardiovascular disease and other complications of atherosclerosis are the most common cause of death in patients with chronic renal failure in maintenance hemodialysis (MHD). Carotid ultrasonography is a simple non-invasive tool to investigate the vascular system, by means of intima media thickness (IMT) measurement and carotid wall calcifications. OBJECTIVE: To determine IMT and the presence of plaques, and their possible clinical relationships; finally we tried to investigate whether they would predict cardiovascular morbidity and mortality in patients in MHD. METHODS: We studied 60 MHD patients (age 68 +/- 13 years, 48% male, 50% diabetics, time on MHD 32 +/- 11 months) and a control group of 274 people matched for age and sex. Follow-up period was 66 +/- 13 months. MEASUREMENTS: Demographic and clinical data, serum levels of homocysteine (tHcy), folic acid (FA) and B6 and B12 vitamins. IMT was measured by high-resolution B-mode ultrasonography. RESULTS: IMT was higher in MHD patients than in those in the control group (0.947 +/- 0.308 vs 0.619 +/- 0.176 mm; P < 0.001). IMT was related with age (r = 0.268; P = 0.038), diabetic (r = 0.650; P < 0.001) and hypertensive condition (r = 0.333; P = 0.012), but not wih lipids, tHcy or FA. Patients who suffered from coronary artery disease, peripheral artery disease or stroke had higher IMT than those without those events (1.156 +/- 0.371 vs 0.875 +/- 0.285 mm; P < 0.001; 1.205 +/- 0.374 vs 0.911 +/- 0.231 mm; P = 0.007; 1.195 +/- 0.264 vs 0.844 +/- 0.251; P < 0.001 respectively). Something similar occurred with the presence of plaques. During the follow-up period 36 patients died (60%), 67% of them due to cardiovascular causes. IMT was higher in patients who died than those who survived (1.020 +/- 0.264 vs 0.858 +/- 0.334 mm; P = 0.044). The survival rate during the observation period was significantly lower in the final IMT fourth (20%) than in the first (72%) (P = 0.014). The presence of carotid plaques was an independent predictor of cardiovascular mortality. CONCLUSIONS: These findings suggests that measurement of carotid IMT and the presence of wall plaques are useful tools to predict cardiovascular events and mortality in patients in MHD.