Sudden death in infancy: a study of cardiac specialized tissue.

The hearts from 15 cot death patients have been compared with those of 15 controls. In one of the cot death patients an accessory atrioventricular connexion known to be capable of producing ventricular pre-excitation and sudden death was identified. In all hearts examined additional segments of specialized tissue were found in relation to the atrioventricular orifices which may have been significant in producing pre-excitation. Haemorrhagic lesions were present in the atrial myocardium and conducting tissues of hearts from both groups, but no evidence was found of cellular degeneration in the atrioventricular bundle. There is a need for further studies of conducting tissues in sudden death syndromes.