Effects of dimethyl sulfoxide on systemic and cerebral hemodynamic variables in the ischemic canine myocardium.

The effects of dimethyl sulfoxide (DMSO) infusion on cerebral blood flow (CBF) and systemic hemodynamics were studied in a canine model of myocardial ischemia. Immediately after ligation, cardiac output dropped from 2.09 +/- 0.11 (SEM) in the control group and 1.79 +/- 0.13 in the DMSO group to 1.07 +/- 0.21 and 1.0 +/- 0.08 L/min, respectively; there were no significant differences for 2 h. By the third hour and thereafter, the DMSO group had a significantly (p less than .05) higher cardiac output (1.65 +/- 0.08 L/min) than the control group (1.15 +/- 0.10 L/min). The cardiac output increase at 3 h was accompanied by significantly (p less than .05) lower systemic vascular resistance (SVR) in the DMSO group (5315 +/- 248 dyne X sec/cm5) as compared to the control group (7892 +/- 442 dyne X sec/cm5). There were no significant differences in heart rate, mean arterial pressure, pulmonary artery wedge pressure, or cerebral or pulmonary resistances in the control as compared to the DMSO group. Higher CBF values were noted at one hour and thereafter in the DMSO as compared to the control group (p less than .05). Low-dose DMSO given as an iv bolus improved cardiac output and CBF and lowered SVR in this canine model of experimental myocardial ischemia.

Comparison of prosthetic graft materials as intracardiac right atrial patches.

An experimental animal model was developed to study the fate of prosthetic graft materials within the heart. Autologous pericardium, bovine pericardium, polytetrafluoroethylene, woven Dacron, and autologous right atrium (control) patches were implanted into the wall at three sites on the right atrium in each of 10 dogs (six patches for each graft material). The atria were harvested 90-100 days later and histologic examination and quantitation of calcium were performed. Chronic inflammation and fibrosis were found in 29 of 30 grafts. Cartilage formed in 26 of 30 sites and was found both in the center and around the edges of the grafts. In addition to cartilage, bone including marrow elements formed in the two autologous materials at 4 of the 12 sites and in 1 of the Dacron graft sites. Calcium content was greater in the control and the bovine pericardial grafts than in the other graft materials (P = NS). The incidence and degree of inflammation, fibrosis, calcification and cartilage, and bone formation were similar in all materials. We conclude that the healing process of these intracardiac graft materials is a generalized phenomenon independent of the inherent properties of a specific graft material.