Cardiovascular risk markers in hemodialysis patients

Cardiovascular events are the main cause of death in hemodialysis patients. Nevertheless, acute myocardial infarction may be misdiagnosed in uremic patients, because typical markers have a high rate of false positivity. A recent two-year prospective study showed that predialytic high serum concentrations of troponin T and CK-MB mass were associated with high mortality, cardiac mortality, myocardial infarction and unstable angina (MACEs). We studied 16 uremic patients (13 M; 3 W) on standard HD and 6 patients (4 M; 2 W) on on-line HDF, who had been taking folic acid for at least three months. Patients who suffered from acute or chronic cardiac ischemic disease were excluded. Anthropometric parameters, pre and post-dialytic pH, HCO3 and electrolytes did not differ between the two groups. Kt/V and URR% were lower in conventional HD vs on-line HDF (p < 0.04; p < 0.04). ORR% was strongly elevated in on-line HDF compared with HD (p < 0.005). In conventional HD, ORR% was directly correlated with Kt/V and URR% (r = 0.49, p < 0.04; r = 0.48, p < 0.04, respectively). Even in on-line HDF ORR% was directly correlated with Kt/V and URR% (r = 0.79, p < 0.04; r = 0.76, p < 0.05, respectively). Troponin I and CK-MB mass were not significantly different in pre vs post-dialysis, both in standard HD and on-line HDF. Nevertheless, in standard HD postdialytic troponin I correlated with serum sodium concentration (r = 0.93, p < 0.000), potassium (r = 0.67, p < 0.004) and serum chlorine (r = 0.92, p < 0.92, p < 0.000). CK-MB mass showed a correlation with serum chlorine (r = 0.49, p < 0.05). Postdialytic CK-MB mass correlated with serum potassium in on-line HDF (r = 0.83, p < 0.03). Our data suggest that hemodialytic treatments, both standard HD and on-line HDF, do not modify serum troponin I and CK-MB mass. Consequently, we can use these parameters for the diagnostic approach in acute or chronic ischemic heart disease in hemodialysis patients.