Abstract
Objectives:Similar to what has been found in hypertension, elevated peripheral resistance in chronic heart failure (CHF) might be related to microvascular constriction and rarefaction. Our objective was to evaluate both structural and functional microvascular changes in patients with CHF in relation to left ventricular function and neurohumoral activation. Methods:In 25 patients with mild and severe CHF (New York Heart Association class I–II [n= 11] and class III–IV [n= 14]) and 10 age-matched healthy subjects, we studied microvascular density, diameters, and morphology of the bulbar conjunctiva and skin nailfold using intravital microscopy. Results:Total conjunctival microvascular density was higher in patients with mild heart failure compared with healthy controls, whereas it was lower in severe heart failure (medians, 6.75, 4.31, and 3.56 mm/mm2, respectively, p< 0.01). In patients with heart failure, venular density was correlated with left ventricular ejection fraction. Nailfold capillary recruitment during postocclusive reactive hyperemia, a measure of functional reserve capacity, was impaired in patients with severe CHF (p< 0.05). Furthermore, in severe CHF, more abnormal capillaries and enlarged diameters were found in the nailfold (p< 0.05). Conclusions:In heart failure, several microvascular abnormalities occur that differ, depending on the severity of this condition. Microcirculation(2003) 10,471–478. doi:10.1038/sj.mn.7800211