Renal reserve is normal in patients with dilative cardiomyopathy waiting for heart transplantation

Renal reserve was explored by means of an oral protein load (2 g/kg body weight) under the form of cooked red meat in a group of 9 patients with end-stage heart failure (ESHF), class III of the New York Heart Association receiving loop diuretics and angiotensin-converting enzyme (ACE) inhibitors, and in a group of 18 healthy controls (HC) matched for age, gender, and height under an identical dietary regimen providing 40 cal/kg per day, 1 g/kg body weight of protein per day, Na 120 mmol/day, and K 50 mmol/day. Baseline glomerular filtration rate averaged 109.5+/-9.89 ml/min x 1.73 m2 in HC and 71.9+/-8.8 ml/min x 1.73 m2 in ESHF. Renal plasma flow averaged 540+/-27 ml/min x 1.73 m2 in HC and 235+/-47 ml/min x 1.73 m2 in ESHF. The filtration fraction was significantly higher in ESHF (p<0.01). Renal reserve averaged 26.03+/-3.28 ml/min x 1.73 m2 in HC and 27.2+/-7.12 ml/min x 1.73 m2 (not significant). Renal reserve averaged 123.9+/-2.9% in HC and 137.3+/-6.68% in ESHF (not significant). The filtration capacity was significantly higher in HC (p<0.001). The data point to a normalcy of renal reserve in ESHF which may depend on the chronic use of ACE inhibitors.