HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Permission Requests Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Farrar, D. J. Articles by Hill, J. D. Search for Related Content PubMed PubMed Citation Articles by Farrar, D. J. Articles by Hill, J. D.

The Journal of Thoracic and Cardiovascular Surgery, Vol 95, 191-200, Copyright © 1988 by The American Association for Thoracic Surgery and The Western Thoracic Surgical Association

ARTICLES

In vivo evaluations of a new thromboresistant polyurethane for artificial heart blood pumps

DJ Farrar, P Litwak, JH Lawson, RS Ward, KA White, AJ Robinson, R Rodvien and JD Hill
Department of Cardiovascular Surgery, Pacific Presbyterian Medical Center, San Francisco, CA 94120.

To reduce the risk of thromboembolic complications in prosthetic blood pumps, we have developed a new segmented polyurethane elastomer. This material is unique because its mechanical properties for long-term durability and surface properties for biocompatibility have been separated and developed in two distinct materials. Improved thromboresistance is then obtained by a 1% concentration of a new polymeric surface-modifying additive blended with the base polyurethane before fabrication of the blood pump. To evaluate this material in vivo, we performed 10 implants, in calves, of the Pierce-Donachy prosthetic ventricle with blood-pumping sacs and cannulas fabricated from the new surface-modifying additive copolymer blend (Thoratec's BPS- 215M). In four control implants the blood sacs and cannulas were fabricated from Ethicon's Biomer segmented polyurethane, which is the present clinical standard for most artificial hearts and circulatory support devices. The blood pumps were connected from the apex of the left ventricle to the descending aorta in male Holstein calves weighing 82 to 108 kg and were driven pneumatically in the full-to-empty mode with flows averaging 5 to 6 L/min. Each calf was medicated with aspirin and dipyridamole throughout the study period and was electively put to death after 4 weeks for evaluation of explanted blood sacs and for examination of the kidneys for infarction. All 10 explanted blood sacs made with the surface-modifying additive copolymer blend were shiny and completely free of thrombus. Three of the four explanted Biomer blood sacs showed visible red thrombus, and all four showed small areas of white thrombus. The average surface area of the Biomer blood sacs covered with thrombus was 45 +/- 32 mm2. Use of a semiquantitative scale to assess renal infarction demonstrated that nine of 10 animals with a surface-modifying additive copolymer blend blood sac had infarction less severe than the mean infarct score of the animals with a Biomer sac. The surface-modifying additive copolymer blend has excellent mechanical and physical properties necessary for use in artificial heart blood pumps. From these experiments, we conclude that the surface-modified polyurethane blend is superior to Biomer polyurethane in blood compatibility and in freedom from thromboembolic risk. This material is now approved by the Food and Drug Administration for investigational device exemption studies in the Pierce-Donachy prosthetic ventricle.

This article has been cited by other articles:

				S. H. Reichenbach, D. J. Farrar, and J. D. Hill A versatile intracorporeal ventricular assist device based on the Thoratec VAD system Ann. Thorac. Surg., March 1, 2001; 71 (2007): S171 - S175. [Abstract] [Full Text] [PDF]

				J.-O. Defraigne, J. Pincemail, G. Dekoster, R. Larbuisson, M. Dujardin, F. Blaffart, J.-L. David, and R. Limet SMA circuits reduce platelet consumption and platelet factor release during cardiac surgery Ann. Thorac. Surg., December 1, 2000; 70(6): 2075 - 2081. [Abstract] [Full Text] [PDF]

				D.W. Quinn, T.J.J. Jones, and T.R. Graham Mechanical Circulatory Support Sources of Emboli and Neurological Outcome Seminars in Cardiothoracic and Vascular Anesthesia, July 1, 2000; 4(2): 115 - 120. [Abstract] [PDF]

				S Whittaker and C Glanville The Thoratec(R) ventricular assist device system Perfusion, July 1, 2000; 15(4): 363 - 368. [PDF]