Efficacy of local dipyridamole therapy in a porcine model of arteriovenous graft stenosis.

Perivascular delivery of antiproliferative drugs has been proposed as an approach to prevent neointimal hyperplasia associated with hemodialysis polytetrafluoroethylene (PTFE) grafts. We examined this approach to deliver dipyridamole in a porcine graft model. PTFE grafts were implanted between the carotid artery and external jugular vein bilaterally in pigs. During the surgery or 1 week post-graft placement, dipyridamole (0.26-52 mg) alone or incorporated in microspheres was mixed with an injectable polymeric gel and applied to the graft-arterial and graft-venous anastomoses on one side, whereas the contralateral control graft received no treatment. Three or four weeks after operation, the grafts and adjacent vessels were explanted en bloc and cross-sections of the anastomoses were examined histologically. The degree of neointimal hyperplasia was quantified by planimetry. In separate experiments, dipyridamole was extracted from the explanted tissues and assayed by spectrofluorometry. The normalized median hyperplasia areas of the treated and control graft-venous anastomoses were 0.45 (25th-75th percentile, 0.30-0.86) and 0.24 (0.21-0.30), respectively (N=7; P=0.08). The median hyperplasia areas of the treated and control graft-arterial anastomoses were 0.12 (0.07-0.39) and 0.11 (0.09-0.13), respectively (N=7; P=0.31). The dipyridamole levels in the vascular walls around the anastomoses were at or above the in vitro inhibitory concentrations for approximately 3 weeks. These results suggest that the local perivascular sustained delivery of dipyridamole, even at high dosages, was ineffective in inhibiting neointimal hyperplasia associated with PTFE grafts in a porcine model.

[Possibilities of hemosorption in the compensation of cardiac dysfunction in patients with ischemic heart disease associated with diabetes mellitus]. / Vozmozhnosti gemosorptsii pri kompensatsii serdechnoi disfunktsii u bol'nykh ishemicheskoi bolezn'iu serdtsa v sochetanii s sakharnym diabetom.

A total of 36 patients with unstable angina and type II diabetes mellitus were studied in the dynamic. All the patients underwent extracorporeal hemocarboperfusion. Marked improvement in the inotropic function of the myocardium was noted with the increase in the rate of relaxation and contraction of the posterior wall of the myocardium. A decrease in the pressure in the lesser circulation and specific peripheral resistance were registered. Using radiometry technique a corresponding decrease in the volume of extravascular fluid in the lungs was observed.

[Hemosorption in the combined treatment of patients with ischemic heart disease and diabetes mellitus]. / Gemosorbtsiia v kompleksnom lechenii bol'nykh ishemicheskoi bolezn'iu serdtsa i sakharnym diabetom.

Extracorporal hemosorption was carried out in 42 patients with diabetes mellitus and ischemic heart disease and a positive effort was observed. This was manifested in a reduction of the clinical manifestations of ischemic heart disease: decrease of the frequency, duration and intensity of stenocardia attacks, 2.5 times reduction on necessity in coronarolytic agents. Hemosorption was effective in the control of arrhythmia and disorders of cardiac conduction. The postsorption period was characterized by stabilization of diabetes mellitus reduction of diurnal fluctuations of glycemia and glucosuria, decrease of peroral sugar-reducing agents.