[1] Interreg Clin Diagnost Ctr, Dept Cardiothorac Surg, Kazan, Russia
[2] Univ Hosp Cologne, Heart Ctr Cologne, Dept Cardiothorac Surg, Cologne, Germany
[3] Kazan Fed Univ, Kazan, Russia
[4] Republican Clin Hosp, Kazan, Russia
[5] Kazan State Med Univ, Kazan, Russia
[6] Ltd Liabil Co Angiolife, Kazan, Russia
[7] Univ Hosp Cologne, Dept Cardiothorac Surg, Kerpener Str 62, D-50937 Cologne, Germany