Compensatory and adaptive changes in microcirculation and left ventricular function of patients with chronic iron-deficiency anaemia.

The severity of alterations in the microcirculatory bed and the incidence rate of myocardial dysfunction in 299 female patients with differently severe iron-deficiency anaemia (IDA) as a mechanism of compensation and adaptation towards chronic anaemic hypoxia was investigated. Significant changes, mainly in the venular and capillary part of the microcirculatory bed in conjunctival biomicroscopy were observed. An increased diameter and a decreased linear density of the venules along with microcongestion foci, microhaemorrhages, an enhanced undulation and irregularity of both venules and capillaries and a 'sludge-phenomenon' were demonstrated. Echocardiographically, a significant enlargement of telediastolic and telesystolic dimensions and volumes of the left ventricle, a hyperdynamic working regimen of the heart with increased cardiac output and stroke volume were observed with advancing severity of IDA and microcirculatory alterations. A slight reduction of myocardial contractility was found only in the cases with a severe degree of anaemia. The treatment performed with parenteral iron induced a complete reversibility of both myocardial and microcirculatory changes with the moderate and slight degree of IDA while there was a delayed reversibility concerning normalization of the values of haemoglobin and serum iron that required a more prolonged follow-up of these patients.