[Orthotopic heart transplantation with sinus venosus incision of right atrium in dogs--preservation of sinus node and original right atrium].

Orthotopic heart transplantation with sinus venosus incision of right atrium was aimed to preserve the sinus node, terminal crista, sinus node artery and whole right atrial muscle of the transplanted heart. This transplant procedure was performed in eight mongrel dogs and electrocardiogram was followed up to five postoperative months. Direct cross circulation technique was employed as an alternative of cardiopulmonary bypass. Donors and recipients were 6 to 8 kg mongrel puppies, and 19 to 25 kg adult dogs supported the cross circulation. Myocardial protection of the donor heart was carried out by low-flow continuous potassium cardioplegia and topical cooling. Right atrial incision of the donor heart was made longitudinally in the posterior wall of sinus venosus. After a median sternotomy, ascending aorta and superior and inferior venae cavae of the recipient were cannulated and connected respectively with carotid artery and jugular vein of the cardiopulmonary support dog. Electrocardiogram, arterial pressure and central venous pressure of the recipient were monitored, and an electro-magnetic flow meter was employed for measuring the blood flow of direct cross circulation. The native heart was resected after aortic cross-clamping, and left atrium and atrial septum were sutured continuously. Sinus venosus incision of the donor heart was anastomosed to the recipient's right atrium. Ascending aorta and pulmonary trunk were reconstructed in the standard fashion. Aortic cross-clamp time was less than one hour and sinus rhythm of the transplanted heart was continued in all cases. Five of the eight dogs were alive postoperatively for one week to five months.(ABSTRACT TRUNCATED AT 250 WORDS)