Prognostic utility of impedance cardiography measurements in elderly hemodialysis patients with coronary artery disease

Abstract

Aim: We evaluated the utility of impedance cardiography (IC) in elderly hemodialysis (HD) patients with coronary artery disease (CAD).

Patients and methods: Seventy-five HD patients (30 with CAD) participated. IC cardiac output (ICCO), systemic vascular resistance and pulse pressure (PP) were calculated at baseline, and 30 and 180 days after study entry. ICCO was compared to echocardiography cardiac output (ECO). Relationships of IC measurements and cardiovascular mortality were assessed. Patients were followed up for 6 years after study entry or until death due to cardiovascular events.

Results: ICCO and ECO were strongly correlated (r = 0.94, p < 0.001). ICCO correlated inversely with PP (r = -0.61; p < 0.001). Thirty fatal cardiovascular events were recorded. Using the bayesian' information criterion, multivariate Cox regression models revealed that increased PP and New York Heart Association (NYHA) class as well as decreased diastolic blood pressure (DBP) were predictors of cardiovascular mortality. Having a DBP <60 mm Hg (adjusted for NYHA) yielded a hazard ratio of 2.8 (95% confidence interval = 1.2-6.7).

Conclusion: IC accurately estimates the hemodynamic status in HD patients with CAD. Deterioration of cardiovascular performance expressed by decreased DBP values, adjusted for NYHA, may help to predict outcome.