Comparison of microvascular distensibility in two different
vascular beds in idiopathic dilated cardiomyopathy.
Wroblewski, Henrik, Tove Nrgaard, Stig Hauns, and Jens Kastrup.
Department of Medicine B 2142, National University Hospital,
Rigshospitalet, University of Copenhagen, and Department of
Pathology, Hillerd County Hospital, Denmark
APStracts 2:0248H, 1995.
The local isotope washout technique allows discrimination between
blood flow in skin and muscle. Arteriolar constriction, mediated by
the sympathetic nervous system, is abolished in a
papaverine/histamine relaxed vascular bed. The microvascular
distensibility of relaxed resistance vessels was measured in skeletal
muscle and skin of the lower limb in patients with congestive heart
failure (CHF) secondary to idiopathic dilated cardiomyopathy and in
healthy subjects. The vascular transmural pressure was elevated 40
mmHg by head-up tilt and caused an increase in muscle blood flow by
11+/-9% in 20 CHF patients compared with that of 44+/-20% in 11
control subjects (p < 0.0003). Also the increase in skin blood
flow was significantly reduced: 31+/-18% in 42 CHF patients compared
to 62+/-29% in 25 control subjects (p < 0.001). Regression
analysis demonstrated a significant association between microvascular
distensibility in skin and skeletal muscle tissue (p = 0.003; r =
0.51; n=31). The structure of the terminal arterioles were determined
in skin biopsies and structural microangiopathy was found in 32 of 42
CHF patients. Multiple regression analysis demonstrated the degree of
microangiopathy to be the only parameter significantly associated
with the microvascular distensibility (p = 0.005), (r = 0.42), (No
association to New York Heart Association functional class, left
ventricular ejection fraction, duration of CHF, age of the subject or
mean arterial blood pressure). We conclude, that patients with
idiopathic dilated cardiomyopathy have similar decreased
microvascular distensibility in both skeletal muscle and skin.
Furthermore, structural alterations in the terminal arterioles seem
to be associated with decreased distensibility and increased
stiffness of the cutaneous microvascular bed.
Received 23 January 1995; accepted in final form 7 June 1995.
APS Manuscript Number H59-5.
Article publication pending Am. J. Physiol. (Heart Circ. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 6 July 1995.