[Prophylactic intraaortic balloon pumping preserves left ventricular systolic function in acute anterior myocardial infarction without cardiogenic shock]

Left ventricular function and prognosis were evaluated in patients with acute myocardial infarction who underwent primary percutaneous coronary intervention supported by intraaortic balloon pumping.Fifty-eight consecutive patients with first acute myocardial infarction were treated between July 1999 and April 2006. Twenty-five had cardiogenic shock on admission, whereas 33 did not. Patients with anterior acute myocardial infarction without cardiogenic shock were divided into the prophylactic intraaortic balloon pumping group (Group 1; n=17) and the rescue intraaortic balloon pumping group (Group 2; n=9).Thirty-day in-hospital mortality was 52% in cardiogenic shock patients, and 3% in non-shock patients. Baseline characteristics of non-shock anterior acute myocardial infarction were similar including Thrombolysis in Myocardial Infarction (TIMI) risk scores (5.1 and 5.0) in the two groups. However, average left ventricular ejection fraction in the convalescent stage was superior in Group 1 (48.7% vs. 37.8%, p = 0.03). Thirty-day in-hospital mortality was 0% in Group 1 and 11% in Group 2 (p = 0.34). Cox's hazard ratio in Group 2 to Group 1 was 2.38 (95% confidence intrerval; 0.84-11.1, p = 0.09) in terms of the subsequent major cardiac events.Prophylactic use of intraaortic balloon pumping starting prior to primary percutaneous coronary intervention preserves the convalescent left ventricular systolic function in patients with high risk for anticipated cardiac events after anterior acute myocardial infarction without cardiogenic shock.