[Short and intermediate term clinical outcome in patients with cardiogenic shock treated with aortic counterpulsation].

BACKGROUND: Despite improvements in coronary care, cardiogenic shock (CS) remains the leading cause of death in patients with dramatic cardiac diseases of which acute myocardial infarction (AMI) is the most frequent event. Conventional therapy for CS with coronary care unit (CCU) monitoring and vasopressor agents to support blood pressure has historically been associated with an 80% to 90% mortality rate in large series. Intra-aortic balloon pump (IABP) therapy for shock results in initial favourable clinical and haemodynamic responses, but ultimately, in most patients, death is merely delayed and hospital mortality still exceeds 80%. In several recent non-randomised series, coronary revascularisation performed early in the course of CS with the use of coronary artery by-pass grafting (CABG) or coronary angioplasty (PTCA) resulted in an apparent reduction in the hospital mortality rate to less than 50% in selected patients with shock.

OBJECTIVES: This study reviews our experience of cardiogenic shock treatment at a time when standard care included aggressive use of the intra-aortic balloon pump counterpulsation, cardiac catheterisation, coronary angioplasty and/or coronary artery by-pass grafting, ventricular septal defect and mitral incompetence repair.

METHODS: We retrospectively analysed 20 patients (13 M and 7 F, with an average age of 62 years and a half) affected by cardiogenic shock consecutively admitted to our CCU between October 1, 1992 and April 1, 1995. Fifteen patients (pts) were hospitalised for AMI, shock and pump failure (2 of them with pulmonary oedema), all with admittance delay less than 24 hours. Five patients were hospitalised for AMI with shock and mechanical defects, of which 3 pts with AMI and ventricular septal rupture and 2 pts with AMI and mitral regurgitation. All patients underwent IABP, coronary angiography (CA) and then were treated with PTCA, CABG and cardiac surgery or medical treatment.

RESULTS: On the whole, 7 pts died (35%): 4 of shock, 1 of haemorrhagic complications, 1 of septic shock in the CCU, and 1 of heart failure after CABG in cardiosurgery. One more patient died of heart failure two months after discharge (late mortality 5%). Out of the 15 patients hospitalised with AMI, shock and pump failure, 13 patients with AMI and CS less than 24 hrs were treated as follows: 1 patient was successfully submitted to emergency CABG and 12 patients to PTCA of the infarct related artery (IRA). Eight patients enjoyed a good outcome, but 1 patient died of haemorrhagic complications and 4 with a persistently occluded IRA also died (3 in the CCU and 1 after CABG). Of the 2 remaining pts with AMI, shock and pulmonary oedema, 1 patient underwent CABG with success and 1 patient with the 3-vessel disease was submitted to PTCA with reperfusion of the IRA, but he died from reocclusion three days later. Out of the 5 patients with AMI, shock and mechanical defects, 3 patients with AMI and septal ventricular rupture underwent cardiac surgery and CABG with early and late success. One of the 2 patients with AMI, shock and mitral regurgitation underwent cardiac surgery with valve repair and CABG and had a good outcome, the other died from septic complications in the CCU.

CONCLUSIONS: IABP is an useful device for stabilising patients in cardiogenic shock and safely performing angiography as well as PTCA, CABG or surgical correction of all mechanical complications with a more stable haemodynamic balance. Therefore, IABP is an useful tool to improve successful coronary revascularisation after direct PTCA or direct CABG. These data also suggest that the combination of successful coronary revascularisation and intra-aortic balloon pumping can improve survival in pts with cardiogenic shock complicating AMI with early pump failure.