Outcome of cardiogenic shock complicating acute myocardial infarction

Objective: To analyze the characteristics and in-hospital outcome of patients with cardiogenic shock (CS) complicating acute myocardial infarction (AMI) and to evaluate the influence of urgent coronary revascularization on in-hospital mortality. Design: Descriptive study. Place and Duration of Study: The Aga Khan University Hospital, Karachi. January 2001 to December 2001. Materials and Methods: All consecutive patients with AMI and CS, admitted at The Aga Khan University Hospital, Karachi Pakistan, during the year 2001 were reviewed. A pre-designed questionnaire was used for data collection. Analysis was done using the SPSS statistical package. Results: Out of 615 patients with AMI, 53 (8.6%) had CS. Mean age was 60.9 ± 10.7 years. 62.3% were men, 52.8% were hypertensive and 43.4% were diabetic. Most infarcts were anterior in location (56.6%). Thrombolytic therapy (Streptokinase) was administered to 43.5% of patients with ST segment elevation myocardial infarction. 64.2% required ventilatory support while swan ganz was used in 37.7%. Intra-aortic balloon pump was inserted in 39.6%. Ventricular tachycardia was the most common complication (39.6%). Overall in-hospital mortality was 54.7%. CS associated with mechanical complications had 80% in-hospital mortality. In patients without mechanical complications (n=48), in-hospital mortality was significantly lower in the revascularization group (31.6% vs. 65.5%, p-value = 0.021). However, there were significant differences in the baseline characteristics in the two groups because of the selection bias. Conclusion: CS occurring in patients with AMI has an extremely poor prognosis. Patients selected for revascularization strategy has favorable in-hospital outcome.