The Role of Kidney Biopsy in Heart Transplant Candidates With Kidney Disease

Background. Kidney disease is common in patients with advanced heart failure and can result from intrinsic parenchymal disease or to reversible hemodynamic factors. Distinguishing the two is difficult but is important when selecting patients who will benefit from combined heart and kidney transplantation (HKT) versus heart transplantation (OHT) alone. The goal of this study was to characterize kidney biopsy findings in this population and follow the outcome of patients based on the biopsy results. Methods. Thirty heart transplant candidates with an estimated glomerular filtration rate less than 40 mL/min or proteinuria greater than 500 mg/day or a history of amyloidosis underwent kidney biopsies between June 2001 and March 2009. The renal pathologic diagnosis as well as the percent tubular atrophy and interstitial fibrosis on renal biopsy were assessed. Results. Proteinuria and glomerular filtration rate at the time of evaluation for heart transplant did not correlate with the degree of fibrosis on biopsy. On the basis of the biopsy results, nine patients were listed for OHT and eight patients were listed for HKT. One patient originally triaged to receive OHT and was listed for HKT due to subsequent worsening of renal function. Eight patients received OHT, none required dialysis during a median follow-up period of 18 months. Conclusions. Renal biopsy provides useful diagnostic information to differentiate intrinsic renal disease from renal hypoperfusion and helps guide the decision for OHT alone versus combined HKT.