Morphological and Functional Characteristics of the Right Ventricle Functioning as a Systemic Ventricle for Decades After an Atrial Switch Procedure for Complete Transposition of the Great Arteries

Described herein are certain clinical and cardiac morphologic findings in 4 adults with complete transposition of the great arteries who underwent the Mustard procedure in the newborn period or in childhood and each lived >30 years thereafter before either having orthotopic heart transplantation (3 patients) or dying while awaiting orthotopic heart transplantation. Compared with the wall of the left ventricle, the wall of the right ventricle (the systemic one) was much thicker, the myofibers much larger, and either grossly-visible or microscopic-sized scars were present in its wall. Additionally, some intramural coronary arteries in the right ventricular wall were numerous, large, had thick walls, and often narrowed lumens. That the Mustard operation provided the necessary time for the right ventricle (the systemic one) to develop to its fullest is a tribute to this procedure. ©2019 The Authors