Monday Afternoon, April 27, 1964

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

Grand Ballroom

8. Two Years Clinical Experience with the Implantable Synchronous Pacer

Sol Center*, David Nathan*, Chang Wu*, and Dairo Duque*,

Miami, Fla.

Sponsored by Thomas H. Burford

The first pacer to synchronize atrial and ventricular contractions in the human heart was implanted in June, 1962. More than twenty synchronous pacers have been implanted in the past two years for the correction of complete heart block and various cardiac arrhythmias. Cardiac output determinations before and after surgery in patients with heart block have shown an increase in cardiac output at increasing ventricular rates in the majority of patients. Repeated measurements of the P wave and ventricular threshold were carried out over a twelve month period in ten patients. Maintenance of an adequate atrial potential and a ventricular threshold of less than three millivolts were present in all but the two infected cases, proving the feasibility of long term synchronous pacing. Follow-up has been obtained in all patients. The cause of death has been determined in those who died in the two year period. The performance of the pacer during periods of normal sinus rhythm and in the presence of atrial or ventricular arrhythmias will be discussed. Recent changes in the pacer parameters and surgical technique will be presented.

9. Cor Triatriatum-A Diagnostic Surgical Enigma

Claude Grondin*, Arnold Leonard*, Kurt Amplatz*,

Ray C. Anderson*, Jesse E. Edwards*, and

Richard L. Varco, Minneapolis, Minn.

The intriguing condition, cor triatriatum, presents a challenging diagnostic problem, yet simplicity of surgical correction (with good record of survival) as demonstrated in three of four operated cases, makes prompt diagnosis of this defect incumbent on the diagnostician. Six cases of cor triatriatum are presented. The embryologic origin of this anomaly is discussed in an attempt to correlate and differentiate this entity from supra-valvar stenosing ring of the mitral valve, atresia of the common pulmonary vein, anomalous pulmonary venous return, and hypoplasia of the pulmonary veins. The combined diagnostic studies of angiocardiography, cardiac catheterization, and electro-cardiography have demonstrated the feasibility of arriving at a preoperative diagnosis of this defect. Three of the four patients subjected to corrective surgery are living today. The overlooked anomalous return of the pulmonary veins into the left innominate vein accounted for the only operative death. Results of postoperative catheterization have shown return to normal pulmonary artery and right ventricular pressures. Early presumptive diagnosis of cor triatriatum, especially in infants who present with left heart failure, could lead to prompt correction and increased salvage, rather than terminate as painful awareness at the final pathological examination.

10. Surgical Treatment of Congenital Aortic Stenosis: Valvular, Subvalvular and Supravalvular

Thomas Putnam*, Paul D. Harris*, William F. Bernhard, and

Paul Hugenholtz*, Boston, Mass.

Three hundred and twenty-four patients with congenital aortic stenosis have been evaluated during a six-year period, 1958 to 1963. Of this number, 82 have had surgical correction of their defects. Valvular stenosis was present in 57 patients (70%), a subvalvular fibrous ring was noted in 18 patients (22%), and supravalvular obstruction occurred in 7 (8%). Males predominated in the valvular stenoses (90%), while 60% of the supravalvular stenosis group were females. The syndrome of growth retardation, mental deficiency, and peculiar facies was present in 40% of the supravalvular cases. The ages of all patients ranged from 24 months to 28 years. Associated congenital cardiac defects were present in 24 patients (30%): valvular stenosis 20%, supravalvular 40% and subvalvular 50%. Coarctation of the aorta was the most frequent lesion (16 patients, 20%). Symptoms of angina and syncope were common in the subvalvular cases, in contrast to the valvular stenosis group, who were frequently asymptomatic. The overall mortality in patients with valvular stenosis was 3%. Death occurred in 5 other patients: 2 supravalvular and 3 subvalvular. Five of the eight fatal cases (70%) had associated cardiac lesions. Postoperative follow-up data will be presented.

11. Complete Correction of Tetralogy of Fallot. Clinical and Hemodynamic Results in 80 Patients Studied Postopera-tively by Recatheterization

C. Walton Lillehei, and Morris J. Levy*,

Minneapolis, Minn.

Tetralogy of Fallot became correctable in 1954. In assessing the value of a new surgical procedure, an accurate postoperative evaluation by objective methods is particularly important. In this study are included all patients with the tetralogy malformation treated surgically by the authors since 1954, and who have had postoperative recatheterization. Since all patients had a preoperative catheterization, hemodynamic data for comparison has been available. The interval between surgery and recatheterization varied from 4 months to 9 years, and the age range of patients studied from infancy to 55 years. To date, 80 patients have been studied, and approximately 70 per cent have been found to have normal or very near normal right heart physiology. The remainder are approximately equally divided between those with a closed ventricular defect but significant gradients remaining across the pulmonic outflow tract, or those with a residual shunt with or without some outflow obstruction or pulmonic insufficiency. Fifty-two per cent are completely cured hemodynamically. Analysis of the pathologic anatomy as determined by preoperative angiography and as observed at surgery in correlation with postoperative results have permitted certain deductions of value concerning indications for, and timing of surgery, case selection, and choice of surgical techniques.

12. The Diagnosis and Surgical Correction of Total Obstruction of the Right Ventricle

David C. Sabiston, Jr , William P. Cornell*,

J Michael Criley*, Catherine A. Neill*, and

Richard S. Ross*, Baltimore, Md.

Pulmonary atresia with total obstruction of the right ventricular outflow tract or of the pulmonary valve is a severe form of the tetralogy of Fallot. Ten patients were investigated by angiocardiography and cardiac catheteriza-tion. Total obstruction of the right ventricle was demonstrated in each, five at the infundibulum and five at the pulmonary valve. Although this condition may occur as congenital lesion, review of the data in these cases led to the development of a new concept that this obstruction represented an acquired lesion. A previous subclavian-pulmonary (Blalock) anastomosis was previously performed in all patients, permitting survival despite complete right ventricular obstruction. The characteristic features of this physiopathological entity and intermediate forms in the pathogenesis of the condition will be illustrated by cine-angiography. Seven patients have been operated upon, four of whom have had total correction and are long-term survivors. Clinical manifestations may be quite marked and hemoconcentration severe. Anatomical features which may offer difficulty in operative repair include severe infundibular stenosis, diminutive right ventricular outflow tract, pulmonary valvular atresia, and hyoplasia of the pulmonary artery. The technic of surgical correction will be discussed and illustrated by a cine-film.

13. Surgical Treatment of Ventricular Septal Defect Associated with Pulmonary Hypertension

Grady L. Hallman*, Denton A. Cooley, Robert R. Wolfe*,

and Dan G. McNamara*, Houston, Texas

As continuing refinements in technics of extracorporeal circulation and intracardiac repair enable the correction of ventricular septal defect with ever lower mortality and morbidity, the problem of associated pulmonary hypertension becomes increasingly important. The difficulty imposed on the operative treatment of ventricular septal defect by elevated pressure in the pulmonary arterial system comprises one of the last significant barriers to the successful management of this lesion. Between 1956 and 1963 four hundred and eighty-two operations have been performed for closure of isolated ventricular septal defects. The pulmonary arterial pressure was elevated in 114 instances. The hospital mortality rate was 16 per cent in patients with pulmonary hypertension and 8 per cent in the remainder. Postoperative cardiac catheterization has been performed in sixty-five patients. Experience with this large group of patients has helped define the criteria for selection of patients for operation. Details of current surgical management will be presented including the hemodilution technic of perfusion, transverse ventriculotomy, patch closure of large defects, and the use of elective tracheostomy with assisted respiration following operation. Postoperative clinical and physiologic data extending over a period of seven years will be discussed with particular attention to the fate of patients with persistent pulmonary hypertension.

14. Congenital Heart Disease in Adults

Frank Gerbode, William J. Kerth*, Ercun F. Sabar*,

John J. Osborn*, and Arthur Selzer*. San Francisco, Calif.

t is generally believed that the duration of life among patients with congenital heart disease averages 30 to 35 years. Some individuals reach middle or advanced age, but by this time the abnormal circulation has frequently caused serious secondary changes or some degree of heart failure. Operative correction may be more difficult than during childhood and the postoperative management is more exacting, requiring special attention to respiratory problems and cardiac arrhythmias. We have operated upon more than 150 patients over 21 years of age with congenital cardiac lesions. Two-thirds of these were intracardiac lesions operated upon with cardiopulmonary bypass. Included in this group are 60 patients with atrial septal defect, 13 patients with ventricular septal defect, 3 of whom had severe pulmonary hypertension and 3 who had concomitant aortic insufficiency. The hospital mortality for this group of patients with intracardiac lesions was 11%, for the entire group 7%. It is the purpose of this paper to describe some features of our operative and postoperative management for this challenging group of patients.

*By Invitation