Almost total absence of the left ventricular myocardium with dextro-transposition of the great arteries.

The term parchment heart is used to describe partial to nearly complete loss of ventricular myocardium. We report the first case of transposition of the great arteries with almost total absence of left ventricular myocardium. The latter was not recognized and the child underwent Mustard's operation at four months of age. He died on the operating table. At necropsy, the left ventricular wall was 1 mm in thickness; microscopic examination revealed few myocardial fibers within edematous connective tissue.