Background: Impaired renal function is associated with increased mortality among heart failure patients. Although a significant proportion of heart transplant (HTx) recipients have reduced renal function at 1 year post-HTx, no previous study has evaluated the associated risk for both all-cause and cardiac mortality. Hence, we assessed the relationship between glomerular filtration rate (GFR) at 1 year post-HTx and all-cause and cardiac mortality and development of cardiac allograft vasculopathy (CAV).
Methods: We evaluated 381 patients with a minimum survival of 1 year post-HTx and the Modification of Diet in Renal Disease Study formula was used to calculate estimated GFR. Mortality and angiographic CAV were defined as separate endpoints, and median follow-up was 7.4 and 4.0 years, respectively.
Results: During the follow-up period, 122 patients died and 154 patients developed CAV. Reduced GFR pre-HTx was not a risk factor for either endpoint. Overall, 193 (51%) patients had GFR <60 ml/min/1.73 m at one year post-HTx and this was an independent predictor of all-cause mortality with an adjusted hazard ratio of 1.7 (P=0.01) for a GFR between 30-60 and 3.2 (P=0.006) for GFR <30 ml/min/1.73 m. GFR <60 ml/min/1.73 m at 1 year post-HTx was also associated with a higher risk of cardiac mortality (HR=1.9; P=0.04) but did not predict the development of CAV.
Conclusions: Renal impairment is evident in a majority of HTx recipients at 1 year post-HTx. It is an important risk factor for both all-cause and cardiac mortality but does not predict the development of angiographic CAV.