A technique was investigated for possible application in the treatment of myocardial ischemia and for repair of ventricular aneurysms. Six dogs underwent operations to transpose the latissimus dorsi muscle onto the surface of a tangentially excised area of myocardium. Three dogs were reexplored at 4 months, and 1 was reexplored at 1½ years, A firm union of latissimus dorsi to myocardium was demonstrated macroscopically, and there was microangiographic evidence of neovascularization. The latissimus dorsi muscle flap provides considerable bulk, leaves a minimal donor site defect, has the potential for neovascularization, may provide mechanical cardiac assistance, and is simple to transfer. Further investigation is indicated.