Heparin and low molecular weight heparin (LMWH) derivatives are considered angiogenic factors in ischemic and infarcted myocardium. However, the effect of dalteparin sodium (fragmin, a LMWH derivative) on angiogenesis post infarction has not yet been investigated.Purpose. To assess the effect of systemically-administered dalteparin sodium on left ventricular perfusion and function during remodeling in swine subjected to acute microembolization infarction (MI).Methods. MI was induced in 12 anesthetized female pigs which randomly received dalteparin sodium (12,500U) or placebo through intra-peritoneal osmotic pump, for one week, beginning immediately after the MI. Myocardial perfusion and function were measured using radionuclear scan and echocardiography, respectively, at baseline, immediately post MI, and at 2 and 4 weeks post MI. Dobutamine stress echocardiography was performed 4 weeks post MI. Serum level of basic fibroblast growth factor (bFGF) was analyzed using a commercially available ELISA kit.Results. No differences were observed in myocardial perfusion at all time points following MI. No significant changes were observed in myocardial function and wall motion during the 4 weeks follow-up period, or after dobutamine administration. Serum bFGF did not change throughout the study period.Conclusion. Under the setting of the current experiment, one week of dalteparin sodium administration does not affect myocardial perfusion and function following acute infarction in swine, either at rest or following pharmacological stress.