Monday, Afternoon, April 8, 1963

2:00 P.M. Scientific Session: REGULAR PROGRAM

Emerald Room

8. Surgical Treatment of Tetralogy of Fallot: Experience with Indirect and Direct Technics

Grady L. Hallman (by invitation), and

Denton A. Cooley, Houston, Texas

The introduction of technics of direct or definitive repair of tetralogy of Fallot stimulated most surgeons to abandon the indirect or palliative procedures developed by Blalock and Taussig and by Potts. As experience has accumulated, however, the need for selectivity of operative technic has become apparent in order to reduce over-all morbidity and mortality in some patients. Clinical experience for this presentation includes 450 patients of whom 200 had open correction of the anomaly and the remainder underwent systemic-pulmonary arterial anastomosis. Among the 250 patients undergoing anastomosis, 12% died after operation. Sixty of these patients were less than one year of age and eight died after operation (13%). Systemic-pulmonary shunt is now used routinely in severely cyanotic infants. Open repair using temporary cardiopulmonary bypass in 200 patients resulted in 30 deaths (15%). In 65 patients who underwent direct repair following one or two previous operations 11 died (17%). Technical aspects of open repair in our clinical series will be discussed including the use of dextrose solution to prime the extracorporeal circuit, disposable oxygenator, normothermia, transverse ventriculotomy, patch grafts, and the method for closure of previous anastomoses.

9. Postsurgical Complete Heart Block: Management and Long-Term Results

C. Walton Lillehei (and by invitation) Robert D. Sellers,

and Robert S. Eliot, Minneapolis, Minn.

Management of complete block following open heart surgery has passed through several stages. Early management of this complication was by sympathomimetic amines. This therapy resulted in few survivals. With the introduction of direct myocardial stimulation in 1956, there was a dramatic decrease in initial mortality. Analysis of our experience with 196 patients sustaining complete heart block has revealed important information. The reversion rate was 66%, but no patient reverted to sinus rhythm after four weeks. From 1957-1962, 37 blocked patients were discharged postoperatively in good condition and on Isuprel. Fifty-four per cent of these patients died during the first year despite good medical management. Another died three years and one died four years later. Further, most deaths occurred suddenly in asymptomatic patients and with complete repair of the defect at autopsy. Therefore, we believe, no blocked patient should be discharged without an implanted pacemaker. The need for a variable rate or P wave pacemaker will be substantiated by experimental and clinical data. The type of defect in which persistent block occurs, the techniques, and results obtained with pacemaker implantation in children as young as three years old, and in patients with total aortic valve replacement will also be presented.

10. The Surgical Significance of Hypertrophic Infundibular Obstruction Accompanying Valvular Pulmonic Stenosis

J. W. Gilbert, A. G. Morrow, and

J. L. Talbert (by invitation), Bethesda, Md.

A systolic pressure gradient within the outflow tract of the right ventricle is frequently observed immediately after the relief of valvular pulmonic stenosis. This residual obstruction is generally recognized as being due to secondary muscular hypertrophy but opinion differs as to whether, under these circumstances, infundibulectomy should be performed. The presence, severity and ultimate fate of secondary muscular obstruction was evaluated in 42 patients before and after pulmonary valvulotomy. In every patient preoperative right ventricular angiocardiograms revealed abnormal systolic constriction of the infundibulum and in 21 patients this was particularly severe. The right ventricular pressure immediately after valvulotomy was 50 mm. Hg of more in 22 patients. Late study, however, indicated satisfactory regression of infundibular hypertrophy in all but five patients. Persistence of intraven-tricular obstruction was not related to age, preoperative severity of stenosis, immediate residual gradient, or the presence of a patent foramen ovale. By angiocardiography, however, the outflow tracts of these patients were characteristically deformed. It is concluded that infundibular resection is not routinely indicated at the time of pulmonary valvulotomy but should be predicated upon the presence of certain angiographic findings which may be identified preoperatively.

11. The Surgical Treatment of Acquired Calcine Aortic Stenosis

Donald G. Mulder, William P. Longmire, Jr., and

Albert A. Kattus, Jr. (by invitation), Los Angeles, Calif.

The objective in treating patients with aortic stenosis is to obtain complete and lasting relief from the valvular obstructive process in the safest manner possible. In some instances, debridement of obstructing and immobilizing valvular calcifications (aortic valvuloplasty) can be readily accomplished and the operative objective achieved. In those valves more extensively involved, cusp excision and prosthetic replacement will be necessary. Fifty-seven patients whose predominant lesion was calcine aortic stenosis have undergone operation at the UCLA Medical Center. Cusp debridement was the procedure in 29 cases. Cusp replacement was used in the remaining 28 cases, although debridement was frequently done in addition in this group. Patients were selected for operation on the basis of symptomatology and left heart catheterization data. None were excluded because of age, congestive heart failure, or extensive valvular calcification. The average preoperative pressure differential across the aortic valve was 90 mm. Hg, while postoperatively it was 7 mm. Hg. Operative mortality was 22%, and there were four additional late deaths. The follow-up period has ranged from two months to four years, and 28 patients have been followed for more than two years. The operative technique, including myocardial management, will also be discussed.

12. Clinical Experience with Total Mitral Valve Replacement with Prosthetic Valves

F. Henry Ellis, Jr., Dwight C. McGoon

Robert O. Brandenburg (by invitation), and

John W. Kirklin; Rochester, Minn.

Experience with total mitral valve replacement in 42 patients between January and November, 1962, form the basis of this report. This period is selected for analysis because in it perfusion techniques, myocardial management, and criteria for case selection have been relatively uniform. Reconstructive procedures were done on 161 patients operated upon by open techniques prior to this period without uniform long-term restoration of good valve function. Recently, therefore, we have usually limited operation to patients with severe symptoms, and in the majority, total replacement has been performed. Twenty-six replacements have been done with the Starr-Edwards ball valve prosthesis and 16 with a flexible monocusp prosthesis. There were 17 hospital deaths. When patients requiring operation on more than one valve are excluded, hospital mortality rates were 13% with the small monocusp valve and 28% with the ball valve. Although mortality rates from total valve replacement are reported to be high, patients surviving without complications from the prosthesis have an excellent result even when advanced chronic congestive heart failure was present preoperatively. Our surgical experience will be analyzed with the purpose of (1) identifying the types of cases most suitable for reconstructive operations and (2) reducing the complications from mitral valve prostheses.

13. Surgical Treatment of Dissecting Aneurysms of the Aorta with Cardiac Tamponade

Michael Rohman (by invitation), Robert H. Goetz

(by invitation), and David State New York, N.Y.

Over 50% of dissecting aneurysms of the aorta originate in the ascending portion of this vessel in such proximity to the aortic valve that even minimal retrograde extension may be lethal as a result of 1) rupture into the pericardium, 2) acute insufficiency of the aortic valve or 3) compression of the coronary arteries. Fortunately there frequently are a number of hours or days between onset of symptoms and death. This provides sufficient time for complete diagnostic studies and institution of corrective surgery. We have had experience with three patients during the past year who developed dissecting aneurysms of the ascending aorta. Two of the three patients had developed signs of cardiac tamponade from hemorrhage into the pericardium and all had acute aortic insufficiency. Prograde and retrograde aortography confirmed the diagnosis. All three patients underwent successful excision of the proximal ascending aorta harboring the dissection, reposition of the aortic cusps, and teflon graft replacement using cardiopulmonary bypass and iced saline cardioplegia. Slides will be shown to demonstrate the diagnostic methods and pathology encountered. A short movie will demonstrate the operative technique and document the presence of hemopericardium (350 cc.) in one of the patients, resulting in severe cardiac tamponade.