Inserting intra-aortic balloon pumps prior to angioplasty in patients with acute myocardial infarction (AMI) does not reduce the scope of heart muscle damage, a condition referred to as infarct size, according to a new study conducted by Duke University Medical Center researchers. The findings were published online today in the Journal of the American Medical Association (JAMA), and presented at the European Society of Cardiology in Paris, France.