CHICAGO—Elevated troponin levels are associated with renal insufficiency in patients with heart failure, a new study found.
Heart failure patients with a glome-rular filtration rate (GFR) less than 30 mL/min per 1.73 m2 were almost four times more likely to have elevated troponin than patients with GFR of
60 mL/min per 1.73 m2 or greater, according to researchers who studied heart failure patients enrolled in the Christiana Care Health System in Delaware. Nephrologist Claudine Jurkovitz, MD, director of operations at the ChristianaCareCenter for Outcomes Research in Newark, Del., presented findings here at the American Heart Association 2006 Scientific Sessions.
In patients with normal kidney function, troponin level is used to diagnose MI, but in many patients with CKD troponins are already elevated, Dr. Jurkovitz explained. Thus, it is not clear how to interpret troponin level in CKD patients suspected of having acute coronary syndromes. “Most of the time, these patients will have troponins measured serially, to see if the already elevated troponin levels go up even more,” she said.
“In this cross-sectional study, we found a strong association between median troponin level and GFR. In my opinion, a rising troponin level is related to a worsening of heart failure, but this needs to be analyzed,” she said.
Although the mechanisms of elevated troponin in patients with kidney disease are unclear, results suggest that troponins should be systematically measured in patients with heart failure and compromised kidney function to stratify them appropriately and to guide their therapy,
Dr. Jurkovitz said.
Of the 709 patients analyzed, 60.2% had a GFR less than 60 mL/min per 1.73 m2. The patients had a mean age of 73.2 years; 43.2% had diabetes and 51.3% had hypertension. Troponins were elevated in 42.2% of the population. A troponin level above 0.03 ng/mL is considered elevated.