Coronary microcirculation and cardiovascular pathology

The recent arrival of new techniques for exploring the coronary microcircul ation has facilitated assessment of both the incidence and consequences of disorders of this network in a large number of cardiovascular diseases. The microcirculation is affected in numerous cardiomyopathies in the presence of different cardiovascular risk factors and also following cardiac transpl antation. Dysfunction of the microcirculation may correspond to a reduction in the surface of the maximum section of coronary arterioles, which involv es multiple mechanisms, although this phenomenon does not appear to play a role in ischaemic heart disease. Reduced coronary now is most frequently re lated to vascular rarefaction of multifactorial origin, including greater o r lesser degrees of intimal proliferation, perivascular fibrosis, hypertrop hy of the media and extrinsic compression.