Deterioration in Heart Function Associated with Progression to Kidney Failure
The progression of chronic kidney disease (CKD) to kidney failure (end-stage renal disease or ESRD) is associated with less efficient pumping of blood by the heart. This decline in the “ejection fraction”—the amount of blood that leaves the heart with each contraction versus the amount that is left behind—may contribute to the increased risk of cardiovascular disease and death that is seen in patients who are undergoing dialysis. These findings come from the Chronic Renal Insufficiency Cohort (CRIC) Study, one of the largest and longest ongoing studies of CKD epidemiology in the United States.
In the current report, CRIC researchers focused on a subset of patients who had progressed from advanced CKD to ESRD over the course of the study, and who had undergone an echocardiogram—a test that produces a detailed moving image of a beating heart—both while they had advanced CKD and shortly after they had progressed to ESRD. These tests provided detailed “before” and “after” information about the patients’ heart structure and function as their kidney function deteriorated.
Nearly three-quarters of patients with advanced CKD or ESRD have a condition termed left ventricular hypertrophy, which means that the main pumping chamber of their hearts is larger than normal because it must work harder to pump blood throughout the body. The researchers noted that there was no difference in the degree of left ventricular hypertrophy as patients progressed from advanced CKD to ESRD. However, the average ejection fraction decreased slightly, but significantly, during the transition to ESRD. This was observed across all patients regardless of their age, race, diabetes status, or the type of dialysis (hemodialysis or peritoneal dialysis) they were receiving.
This is the irst study to examine changes in heart structure and function in patients as they progress from CKD to ESRD. Future studies will explore the mechanisms responsible for the decline in ejection fraction that accompanies progression to ESRD.