Saturday Afternoon, March 28, 1953

2:00 P.M. Executive Session.

3:00 P.M. Scientific Session.

Address of the President, Robert M. Janes, Toronto, Ont.

19. The Experimental Closure of Atrial Septal Defects.

Harris B. Shumacker, Jr., and Thomas C. Moore (by invitation),

Indianapolis, Ind.

Efforts at experimental surgical closure of atrial septal defects have been directed along three general lines. The first involved various methods of direct closure of the defect by application of pericardial or auricular appendage grafts through the opened right atrium with the venous inflow to the heart temporarily occluded. The second was concerned with placement of grafts through a rubber-capped glass cylinder inserted into the base of the auricular appendix. The grafts could thus be introduced into the atrial chamber and fixed over the defect without stopping heart function and without blood loss. Both methods appeared to have definite promise but had intrinsic features which were not considered ideal for application to the problem in patients. The third method seems ideally suited to use in human patients and has been successfully used in one case. It can be carried out in dogs without mortality and with complete closure. It permits direct suture with good vision and palpation of the defect, without blood loss or danger of embolism or intracardiac thrombosis and without interfering with heart function. Autogenous tissue is used. The procedure consists of suture of a pocket of pericardium to a linear incision in the atrial wall, its inversion into the atrial chamber, and suture of one wall of the pocket to the margins of the defect. Details of the various methods will be given and results presented.

20. Surgical Treatment of Mitral Insufficiency: An experimental Study.

Max G. Carter and John M. Gould (by invitation),

New Haven, Conn.

A series of experiments has been performed on mongrel dogs in an effort to develop a method of treatment for mitral valve insufficiency. A plastic ball, encased in a tubed pedicle of pericardium, has been placed behind the lateral leaflet of the mitral valve by insertion directly through the left ventricular wall. The procedure has been well tolerated by the experimental animals.

Anatomical reduction in the size of the left ventricular inflow tract has been obtained. Significant endocardial or myocardial damage has not been observed.

The operative technic, anatomic and physiologic observations will be presented.

21. Pulmonary Valvuloplasty Under Direct Vision: The Aid of a Mechanical Right Heart.

F. D. Dodrill, Robert A. Gerisch (by invitation), Aran S. Johnson

(by invitation) and Edward Hill (by invitation), Detroit, Mich.

There is, at present, a blind operative procedure on the pulmonary valve in patients with congenital pulmonary stenosis. This is known as the Brock operation and is a good one. It has vastly improved numerous patients. There is some suggestion, however, that patients who have had the Brock operation may again develop a high right ventricular pressure, indicating that the stenosis has recurred. If improvements are to be made from this point on, it is probable that they must be made by exposing the pathological structure.

Patients with pulmonary valve stenosis, who do not show arterial oxygen unsaturation and who do not show simultaneous opacification of the aorta ‘and pulmonary artery during angiocardiography, may have only the pulmonary valve defect. Such patients do not have polycythemia or other signs of anoxia. In such a patient, a temporary by-pass of the right heart is possible using the mechanical right heart. The lungs and left ventricle continue to perform their functions.

A mechanical right heart has been used to by-pass the right heart in such a patient. Blood is withdrawn from the right atrium, passes through the mechanical heart and back into the artery to the right lower lobe, the cannula pointing centrally. The suction on the cannula in the atrium tends to cause the atrial wall to occlude the tricuspid valve. If this is not an air tight closure, a light clamp may be applied across the conus proximal to the pulmonary valve. The main pulmonary artery is separated from the ascending aorta and a clamp is placed across it. This prevents backflow from the pulmonary circuit. The pulmonary valve is now completely isolated. An incision is made in the base of the pulmonary artery and the valve is readily exposed. A plastic valvuloplasty is done under direct vision.

A movie will be shown of the entire operation.

6:30 P.M. Cocktails and Dinner, Fairmont Hotel.

Attendance limited to Members of the Association and their wives, Invited Speakers and their wives.

Dinner Dress.