THE CONCEPT of surgical excision as a treatment for myocardial infarction was proposed by Murray,1 who in 1947 observed improvement in cardiac function after excision of experimentally produced infarcts. Experimental and clinical studies by Heimbecker et al2 demonstrated the feasibility of this method of treatment and stimulated our interest in the problem. Our own experimental results,3 as well as those of Jude et al,4 support the work of Heimbecker. Our experimental and clinical experience with this form of treatment is described in this paper. Experimental Method Forty mongrel dogs weighing 13.0 to 20.2 kg were studied. Animals were anesthetized with intravenously administered pentobarbital sodium and respiration was supported by endotracheal insufflation with room air using a respirator. The inferior vena cava was catheterized via the right femoral vein for central venous pressure measurements. The left femoral vein was cannulated for infusion of fluids and for dye