Median sternotomy is a standard surgical technique used for left ventricular assist device (LVAD) implantation. However, if sternotomy has a prohibitive surgical risk, LVAD implantation can be performed through only left thoracotomy. We managed a patient with endstage heart failure who had recently undergone coronary artery bypass grafting (CABG) elsewhere. The patient also had a deep sternal wound infection and bacteremia. Because of refractory cardiogenic shock, we performed extracorporeal membrane oxygenation (ECMO). After multiple mediastinal washouts and omental flap placement, ECMO was converted to extracorporeal LVAD (from the left ventricular apex to the descending aorta) through a left thoracotomy. The extracorporeal LVAD was maintained for 18 days and replaced by the HeartMate 3 LVAD. The patient was discharged in good condition 115 days after CABG.