Therapeutic angiogenesis is a potential treatment modality for myocardial ischemia. phVEGF-A(165), phPDGF-BB, or a combination of the two were injected into the myocardial infarct border zone in rats 7 days after ligation of the coronary left anterior descending artery. Cardiac function was measured by echocardiography. Hearts were harvested 1 and 4 weeks after plasmid injection. phVEGF-A(165) increased capillary density more than phPDGF-BB, and phPDGF-BB preferentially stimulated arteriolar growth. The combination increased both capillaries and arterioles but did not enhance angiogenesis any more than single plasmid treatments did. VEGF-A(165) and the combination of phVEGF-A(165) and phPDGF-BB counteracted left ventricular dilatation after 1 week but did not counteract further deterioration.