Monday Afternoon, May 16, 1966

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

Ballroom

8. Surgical Management of Hernia of the Foramen of Morgagni

Thomas P. Comer*, and O. Theron Clagett, Rochester, Minn.

In a recent publication the commonly held concepts that foramen of Morgagni hernias occur through a defect in the anterior diaphragmatic attachments and that they have a peritoneal sac were challenged. Although the authors based their conclusions on a single cadaver dissection, their paper did stimulate a review of foramen of Morgagni hernias treated surgically at the Mayo Clinic. In a 32-year period from 1933 to 1965, 1750 patients with diaphragmatic hernias of various types underwent operation. In 50, or 2.9%, the hernia involved the foramen of Morgagni. Thirty-five patients were females and 15 were males. The ages of the patients at the time of operation ranged from 3 months to 78 years. Forty-five of the hernias were located to the right of the sternum anteriorly, and one was located on the left; in four patients the hernia was bilateral. In 46 of the 50 patients a definite hernial sac contained abdominal contents. In four cases the diaphragmatic defect was filled with a large fat pad, but there was no true hernial sac. Our experience with this series of patients will be reviewed.

9. Penicillin Epilepsy. Studies on the Blood Brain Barrier During Cardiopulmonary Bypass

A. R. C. Dobell, J. D. Wyant*, K. B. Seamans*, and P. Gloor*,

Montreal, Quebec

Blood stream infection is a tragic complication of valve replacement. Prophylactic antibiotics have a definite place in preventing this complication. It became our habit to give large doses of penicillin intravenously during and following these operations. Two such patients operated upon on consecutive days were in status epilepticus at the conclusion of operation. Following the second operation, penicillin was suggested as a possible cause and it was stopped in both patients. The first patient succumbed shortly thereafter. The pathological changes in the brain were typical of status epilepticus and no other cerebral lesion was seen. The second patient recovered completely. A penicillin assay was done on the CSF of both patients. Animal experiments were designed to evaluate blood-brain barrier permeability to penicillin and its relationship to Cardiopulmonary bypass. Forty-six experiments have been performed to date and they indicate the following: 1) status epilepticus may occur in dogs given massive intravenous penicillin and placed on Cardiopulmonary bypass, 2) similar doses of penicillin are innocuous without bypass, 3) neither acidpsis nor blood transfusion nor hemolysis will produce convulsions in penicillin-loaded dogs not placed on bypass. Current experiments are investigating fat embolism, hypotension and hypothermia as possible causes of the barrier permeability to penicillin.

10. Two Stage Surgical Treatment of Ventricular Septal Defect in Patients Requiring Operation During the First Year of Life: Results of Pulmonary Artery Banding and Subsequent Open-Heart Repair

Grady L. Hallman, Denton A. Cooley, and Robert D. Bloodwell*,

Houston, Texas

If ventricular septal defect produces intractable cardiac failure in infancy in spite of vigorous medical therapy, surgical treatment must be utilized to prevent a fatal outcome. Results of closure of ventricular septal defect using cardiopulmonary bypass in the newborn period were discouraging (41 percent mortality in 31 patients) and led to the adoption of pulmonary artery banding as the procedure of choice when operation became necessary in small infants. Since 1959, sixty-eight patients have undergone banding during the first year of life with a 15 percent mortality. Most of the infants who died had multiple other major cardiovascular anomalies. Relief of heart failure in survivors was frequently striking. Twelve patients have subsequently undergone open-heart surgery for closure of the ventricular septal defect and reconstruction of the pulmonary artery. There was only one death and this occurred in an 11 month old infant in whom total repair was done only 4 months after the first operation because of a poor response to banding. Survivors who have been catheterized have exhibited normal cardiac dynamics. This paper is concerned with indications and surgical technics for banding and total repair and will present results including pre and postoperative catheterization data.

11. Early and Late Results of Operation for Ventricular Septal Defect

Timothy B. Cartmill*, Dwight C. McGoon, James W. DuShane*,

and John W. Kirklin, Rochester, Minn.

Controversy exists concerning surgery for patients with 1) ventricular septal defects (v.s.d.) without pulmonary hypertension, 2) large defects with severe pulmonary hypertension. Relevant data are presented from 432 patients operated upon since January, 1960. Of 179 with large pulmonary blood flow but normal pulmonary pressure (Pp/Ps<0.45) there were no hospital deaths. 2.5% had residual shunts. Cardiothoracic ratio (C/T) decreased in 66%. Height and weight increased in 51 and 45% of children. Results indicate propriety of operative treatment. 72 of 168 patients with severe pulmonary hypertension (Pp/Ps>0.75) and with Rp/Rs of <0.45 and the 77 with Rp/Rs of 0.45 - 0.75 had hospital mortality of 13% and 10% respectively. Residual shunt was detected in 12% and 15%. In the two groups together, C/T decreased in 79%; height and weight increased in 80% and 77%; late studies indicate that the Rp/Rs decreased in 62%. Operative results in infants over 6 months of age were similar to older patients. Hospital mortality was 54% in 19 patients with Rp/Rs>0.75. However, a late fall in Rp/Rs to 0.50 was demonstrated in 2 of the 4 cases studied, suggesting that severely elevated pulmonary vascular resistance is not invariably a contraindication to operation.

12. Factors Modifying Hemodynamic Results in Total Correction of Tetralogy of Fallot

James R. Malm, Sidney Blumenthal*, Frederick O. Bowman, Jr.*,

Kent Ellis*, A. Gregory Jameson*, Mary Jane Jesse*,

and Chin B. Yeoh*, New York, N.Y.

In 1960 a program was instituted based upon the concept that complete surgical correction of tetralogy of Fallot was feasible and well tolerated by patients. One hundred cyanotic patients underwent total correction with seven post-operative deaths. Hemodynamic studies were performed pre-operatively in all patients with documentation of site and severity of outflow obstruction, right ventricular pressure of systemic level and arterial de-saturation. Complications due to left ventricular failure or impaired pulmonary vascular bed were not encountered. There was no correlation between operative results and intensity of cyanosis, hematocrit level, severity of pre-operative symptoms and previous palliative procedures. All living patients are clinically improved. Post-operative catheterization demonstrated 52/60 had good to excellent hemodynamic results. A normal response to exercise was noted as measured by cardiac index, even in the presence of pulmonic valve insufficiency. Residual outflow tract gradients increased with exercise. The anatomy of right ventricle and pulmonary artery limited total correction in some cases - anomalous right coronary artery (4%), peripheral pulmonary artery stenosis (2%), fibrotic pulmonary annulus requiring an outflow patch (10%), end to end Blalock anastomosis (2 cases). The hemodynamic implications of these anatomic problems will be discussed. Survival and the late hemodynamic results were related to the ability to achieve total correction in the operating room.

13. The Ventriculomyotomy Operation for Muscular Subaortic Stenosis: A Reappraisal

W. G. Bigelow, A. S. Trimble*, and E. D. Wigle*,

Toronto, Ontario

Despite its simplicity, the Ventriculomyotomy procedure for the relief of outflow obstruction and decreased compliance of the left ventricle in ventricular septal hypertrophy has not received wide general acceptance and more extensive resection procedures have been described. Recent experimental and haemodynamic studies suggest that these hypertrophic hearts may vary pathologically as well as in their functional derangement. These features may mean that one surgical procedure may not be effective in all forms of this condition. From a group of fifty-five patients with muscular subaortic stenosis, seventeen have been operated upon over the past four years at the Toronto General Hospital. There were two hospital deaths. Postoperative catheterization in eight patients confirms elimination of the systolic gradient at rest, and following digitalization or isoproterenol infusion. The complete follow-up study will be reported for all fifteen survivors. Preoperative catheter and angiographic studies will be correlated with: a) pathology at operation, b) postoperative catheter and angiographic results, and c) clinical assessment. The results from this simple muscle splitting operation may clarify the nature of the functional derangements in this currently controversial type of heart muscle disease and aid in the selection of patients for surgery.

14. Results of the Creation of an Atrial Septal Defect (Blalock-Hanlon Operation) in 90 Patients with Transposition of the Great Vessels

William P. Cornell*, Pittsburgh, Pa., Robert E. Maxwell*,

J. Alex Haller, Jr., Baltimore, Md., and David C. Sabiston, Jr.,

Durham, N.C.

The Blalock-Hanlon procedure for creation of an atrial septal defect was performed in 90 patients with transposition of the great vessels between 1948 and 1964. Half of these patients were less than one year old at the time of the operation and one-third were in the first three months of life. Severe anoxemia and congestive heart failure were the primary factors which prompted surgical intervention. Forty per cent of the patients in the entire series survived the operative procedure, with the highest mortality occurring in infancy. The mechanisms involved in the death of these patients have been reviewed, and the associated cardiac defects and their relationship to the ultimate result have been evaluated and will be discussed. Clinical improvement of the survivors was definite as evidenced by the arterial oxygen saturation which increased an average of 24% in the survivors. Of particular interest are sixteen patients who have survived ten years or longer and who are now doing well. In the entire series there were only five late deaths. With open correction now available for this malformation, it becomes increasingly important to perform a palliative procedure in order that these patients may survive to an age when the definitive operation can be safely performed.

*By Invitation