Morphometry of coronary capillaries in hypoplastic left heart syndrome

Background Hypoplastic left heart syndrome is a condition characterized by a constellation of morphological malformations affecting the left side of the heart. We studied the capillary network, and quantified the capillarization of the ventricular myocardium, which, if different from normal, may have implications for the success of surgical reconstruction. Methods The capillaries were detected by immunohistochemistry using a monoclonal antibody (von Willebrandʹs factor) against the endothelium. Hearts with hypoplastic left heart syndrome have higher mean and maximal diffusion distances from any arbitrary point to the nearest capillary than normal hearts. Results There was no significant difference in the heterogeneity of capillary distribution between the hearts with hypoplastic left heart syndrome and the control heart. Increase in distance was found in both the right and left ventricles. Conclusions Hearts with hypoplastic left heart syndrome show a reduction in the capillarization of both the right and left ventricles compared with age-matched controls. We believe this may be an inherent abnormality of hypoplastic left heart syndrome that may have implications for ventricular development.