Autologous muscle to assist the failing heart: first experiments

This report summarizes early work to explore the harnessing of noncardiac muscle to supplement the work of the failed left ventricle. First experiments, in 1959, investigated the possibility of using the mobilized left diaphragm around the distal portion of the thoracic aorta. A stimulus was delivered to the left phrenic nerve during diastole, causing that portion of the aorta to be collapsed by the contracting muscle and thus act as a pump. A significant rise in diastolic pressure compared with controls was obtained in all experiments. This study and later investigations with a graft sutured to the left ventricle indicated the feasibility and promise of biologic augmentation. The inherent problems of stroke volume and fatiguability of the transposed diaphragmatic muscle, at the repetitive rates required for adequate hemodynamic assistance in the dog, led us to explore other approaches to cardiac assistance.