Cardiogenic Shock (CS) has emerged as the primary cause of death in patients hospitalized for acute myocardial infarction (AMI). Mortality remains in the range of 60-90%. Successful use of temporary ventricular support (TVS) in postcardiotomy cardiogenic shock as well as in staged cardiac transplantation (SCTx) suggests a potential adjuvant therapeutic role in patients with AMI and refractory CS. The objective of the proposed research is to define the role of TVS (Penn State pneumatic) in the group of patients with AMI and CS refractory to current conventional medical and surgical therapy. Patients with drug and intra-aortic balloon refractory CS following AMI will be entered into the proposed study. In patients with inoperable lesions (diffuse coronary artery disease and ischemic cardiomyopathy) subsequent treatment would be based on whether or not the patient is a candidate for SCTx. Patients satisfying transplantation criteria would undergo SCTx utilizing TVS until a donor organ is located. Unsuitable candidates or candidates refusing proposed therapy would be continued with conventional therapy. The group of patients with operable lesions would be then subgrouped based on the underlying pathology and therapy carried out accordingly. Subgroups of patients with mechanical defects (ventricular septal defect, ischemic mitral regurgitation) will then undergo emergent operative repair. Subgroups of patients with pure coronary artery disease with acute occlusions would undergo, if technically feasible, immediate percutaneous transluminal coronary angioplasty. If contraindications to non-surgical reperfusion exist or if this is unsuccessful, immediate coronary artery bypass grafting would be carried out. Patients who remain in shock following non-surgical reperfusion or following technically satisfactory repair of mechanical defects and/or surgical reperfusion will have TVS instituted. Patients not primarily weaned from TVS will then be considered for SCTx if no contraindications exist and the patient is accepting of the procedure. Survival and functional results will be compared to historical controls and in the case of SCTx, comparison will be made to those patients undergoing primary orthotopic heart transplantation at our institution. It is anticipated that the ability of ventricular assist pumping to support all or part of the circulation during AMI and CS refractory to current conventional therapy will improve an otherwise dismal prognosis.
