Skin microvascular distensibility and structural microangiopathy in idiopathic dilated cardiomyopathy and after heart transplantation

Peripheral microvascular function plays an important role in patients with congestive heart failure (CHF). Decreased microvascular distensibility in s kin and structural microangiopathy of the lower leg have been demonstrated in CI IF due to idiopathic dilated cardiomyopathy. Whether microvascular sk in distensibility reverses after heart transplantation and is related to th e structural microangiopathy has not been elucidated before now. Distensibi lity (stiffness) of resistance vessels in the skin was measured using the l ocal isotope washout method in a histamine-relaxed vascular bed at the dors um of the foot. The structure of terminal arterioles was determined from sk in biopsies. The measurements were performed in two studies. A cross-sectio nal study included 20 patients with clinical moderate CHF (NYHA II), 11 sev ere CHF patients (NYHA III and IV), and 28 patients 9 +/- 6 months (mean +/ - SD) after heart transplantation (HTX). Furthermore, 12 patients were stud ied in a longitudinal study before (CHF) and 3 +/- 1 months (HTX-3) and 14 +/- 4 months (HTX-14) after HTX. A control group of 24 healthy subjects was included. In the cross-sectional study, distensibility in skin was reduced with increasing severity of CHF (severe CI-IF 22 +/- 10% and moderate CHF 38 +/- 21% vs controls 54 +/- 14%; P < 0.0001 and P < 0.01, respectively). Distensibility was reduced in patients after HTX (HTX, 41 +/- 18%) compared to controls (P < 0.01), In the longitudinal study, distensibility was decr eased before transplantation (20 +/- 10%, P < 0.0001 vs controls) and incre ased gradually after HTX to 35 +/- 16% at 3 months (P < 0.01 vs CI-IF, P < 0.005 vs controls) and to 40 +/- 12% at 14 months (P < 0.05 vs controls, P < 0.01 vs HTX-3, P < 0.005 vs CHF), Structural microangiopathy was demonstr ated in CHF, but not in HTX, in the cross-sectional study. However, a norma lization could not be demonstrated after HTX in the longitudinal study. We conclude that the decreased microvascular skin distensibility (increased st iffness) gradually reverses after HTX. Furthermore, the structural microang iopathy seems to improve gradually. (C) 1999 Academic Press.