Rarefaction of skin capillaries in patients with anginal chest pain and normal coronary arteriograms

Aims Patients with arterial hypertension often have a reduction in capillar y density (rarefaction) and a reduction in coronary flow reserve because of functional and structural alterations of the coronary microcirculation. Pa tients with chest pain and normal coronary arteriograms may have coronary m icrovascular dysfunction, but it is: not known whether capillary rarefactio n plays a rule in the pathogenesis of this syndrome. The aim of this study was: to compare capillary density in hypertensive and normotensive subjects with anginal chest pain and normal coronary arteriograms vs asymptomatic h ypertensives and healthy controls. Methods and Results We studied 49 patients with typical anginal chest pain, positive exercise testing and normal coronary arteriograms; 22 were hypert ensive and 27 were normotensive. We used intra-vital video-microscopy to ex amine the skin of the dorsum of the middle finger of the non-dominant hand before and after maximization of perfused capillaries with venous congestio n. Mean capillary density was significantly lower in patients with chest pa in and normal coronary arteriograms independent of their blood pressure lev el, compared to normotensive healthy controls. Differences were found both at baseline [51+/-2 (hypertensive) and 57 +/- 2 (normotensive) vs 65 +/- 2 (controls) per 0.56 mm(2) respectively], (P<0.0001) and after maximization [57 +/- 3 (hypertensive) and 59 +/- 2 (normotensive) versus 75 +/- 3 (contr ols) respectively] (P<0.0001). Conclusions Skin capillary density is significantly lower in patients with chest pain and normal coronary arteriograms compared to normotensive contro ls. The pathophysiological importance of capillary rarefaction in patients with chest pain and normal coronary arteriograms remains unknown. Further s tudies are needed to determine whether the abnormality is associated with m yocardial now disturbances: such that the findings can be extended to the h eart.