Changes of myocardial functions in acute hepatic porphyrias. Role of heme arginate administration.

In three patients with attacks of acute intermittent porphyria we found markedly impaired functions of the left ventricle accompanied by ECG changes that returned to normal after administration of heme arginate or cytochrome C administration. In nine patients with other types of porphyria, and in one patient with acute intermittent porphyria not suffering an attack, no significant changes of left ventricle function were observed. The changes seen in patients with an acute attack may be ascribed to acute myocardial hypoxia resulting from defective biosynthesis of heme. We assume that the exogenous supply of heme may improve cellular hypoxia.