however , in 1984 , patients who had a coronary artery bypass graft were older than patients who had percutaneous transluminal coronary angioplasty ( 61.5 versus 56.7 years , p less than 0.01 ) , they required more heart medications ( 2.1 versus 1.5 , p less than 0.01 ) , had more previous infarctions ( 0.8 versus 0.5 , p less than 0.01 ) , and more patients had an ejection fraction of less than 50 % ( 34 % versus 7 % , p less than 0.01 ) .
C0010055
coronary artery bypass graft
C0018787
heart