Abstract 10648: Impact of Mild to Moderate Renal Dysfunction on Left Ventricular Relaxation Function and Prognosis in Ambulatory Patients with Nonischemic Dilated Cardiomyopathy
Introduction: Chronic kidney disease (CKD) contributes to reduced cardiac function, cardiac hypertrophy, and an increased risk of adverse cardiovascular events. Such interactions between CKD and HF represent the pathophysiological basis for the clinical entity known as cardiorenal syndrome. However, the relationship between mild-to-moderate renal dysfunction and cardiac diastolic dysfunction and cardiac events in patients with nonischemic dilated cardiomyopathy (NDCM) has not been fully elucidated.
Hypothesis: We assessed the hypothesis that renal function could be related to cardiac function as well as clinical outcome in patients with NDCM.
Methods: We checked plasma BNP and eGFR, and performed cardiac catheterization in 135 consecutive ambulatory patients with NDCM. We calculated the maximal first derivative of LV pressure (LV dP/dtmax) as an index of contractility. To evaluate LV isovolumic relaxation time, we computed the pressure half-time (T1/2) directly. During a mean follow-up for of 4.8 years, we followed up all patients for the occurrence of cardiac events, which were defined as cardiac death (from worsening HF or sudden death) and unscheduled admission for decompensated HF.
Results: Patients were classified into three groups on the basis of eGFR (mL min-1 1.73 m-2): eGFR ≥ 90 (n = 23, group A), 60 ≤ eGFR < 90 (n = 70, group B), and 30 ≤ eGFR < 60 (n = 42, group C). Whereas LV dP/dtmax did not significantly differ among the three groups, T1/2 was significantly longer in groups B and C than in group A (P < 0.01). Event-free survival in group C was significantly lower than that in groups A and B (P = 0.014, log-rank test). The risk of cardiac events in group C after adjustment for age, sex, and DM was significantly higher than that in groups A and B combined (hazard ratio, 2.77; 95% CI, 1.21 to 6.34; P = 0.016).
Conclusions: These results suggest that even mild renal dysfunction is associated with LV isovolumic relaxation impairment. In addition, moderate impairment of renal function is independently associated with cardiac events in patients with NDCM.
- © 2011 by American Heart Association, Inc.