This volume contains the revised texts of the presentations at the 29th International Congress of the European Society of Cardiovascular Surgery, held from July 2-5, 1980, in Dusseldorf under the presidency of Jan Nielobowicz (Warsaw). We express our gratitude to all the authors who have been partici- pating in the Congress, in particular to the invited speakers A. R. Castaneda (Boston), D. B. Effler (Syracuse), F. Fontan (Bordeaux), F. Robicsek (Charlotte), and D. N. Ross (London) for their cooperation. We are grateful to our colleagues of the Surgical Department B at the University of Dusseldorf, J. A. Herzer, G. Irlich, R. Karfer, and A. Krian, for their help during preparation and organisation of the Congress. Finally, we are indebted to Sanol Schwarz GmbH for its support of this publication. Dusseldorf, June 1981 Wolfgang Bircks Jarg Ostermeyer Hagen D. Schulte Contents The Contribution of European Surgeons to the Development of Modern Vascular Surgery. J. Nielubowicz. With 20 Figures -. ------ Session I Cardiac Surgery Valvular Surgery I Chairman: V. O. Bjork, Stockholm; Co-Chairman: A. Carpentier, Paris Special Morphological Structures Along the Closing Zone of the Mitral Valve. H. Heine and M. Laatz. With:5 Figures --. --. . -. -. . -- 25 Conservative Surgery of the Mitral Valve. Annuloplasty on a New Adjustable Ring. M. Puig Massana, J. M. Calbet, and E. Castells With:5 Figures --------. --. -----. --. ----. -----------------. . . -.