MONDAY MORNING, APRIL 6, 1970

8:30 A.M. Business Session (Limited to Members)

International Ballroom Center

8:45 A.M. Scientific Session: REGULAR PROGRAM

International Ballroom Center

1. Cardiac Transplantation in Man. VIII. Survival and Function

Edward B. Stinson,* R. B. Griepp,* D. Clark,* E. Dong,*

and Norman E. Shumway, Stanford, Calif.

Directly computed survival rates in 18 patients undergoing cardiac transplantation at Stanford University Medical Center show 53% survival at 3 months, 46% at 6 months, 40% at 9 months, and 29% at 1 year postoperatively. Maximum survival in this_ series is currently 14 months with good graft function. Allograft rejection was the cause of death in 3 patients; in one progressive AV conduction disturbances culminated in a fatal Stokes-Adams attack at 10 months. Histopathological examination of the heart showed occlusion of the AV nodal artery by obliterative arteritis, one of the organ-specific expressions of allograft rejection. In 3 other patients immunosuppressive therapy contributed directly to a fatal outcome through potentiation of infectious complications or metabolic toxicity. Four remaining deaths were due to separate causes, including the physiological complications of long-standing pulmonary vascular disease in 2. Hemodynamic evaluation of graft function has been performed in 5 patients, including 2 at one year postoperatively. Normal resting cardiac outputs were found in 4 patients on postoperative days 1 through 3 In one patient cardiac catheterization at 3 weeks showed normal pressures and low normal flows although atrial biopsy 2 days later revealed moderately severe rejection changes. In both patients studied at one year resting pressures and flows were normal with satisfactory responses to exercise. Correlation of these studies with serial exercise tolerance tests, electrocardiograms, and ballistocardipgrams, as well as the results of late evaluation for cardiac reinnervation will be described

2. Pulmonary Valve Autograft for Aortic Valve Replacement

L. Gonzalez-Lavin,* Chicago, Ill., M. Geens,*

and Donald N Ross,* London, England

Sponsored by C. Frederick Kittle

The main problem with aortic homograft replacement of the aortic valve at present relates to their long-term durability. Most of the late failures of the homograft valves have been due to degenerative changes related mainly to the methods of sterilization and storage. To overcome these problems the use of living valves has an immediate appeal. Since June 1967, 84 patients have undergone aortic valve replacement with a pulmonary valve autograft. This procedure has been electively performed in young patients the mean age was 35.6. Sixty-three per cent of the patients were in Class III or IV. The surgical technique will be presented in detail Hospital mortality in the last half of the patients was 71% Postoperative aortic regurgitation has been slightly less than with homograft valves. The majority of the patients with a diastolic murmur post-operatively are asymptomatic. In only 4.4% of the patients aortic regurgitation was moderately severe. These three instances were considered as definite valve failure. All three instances have been due to malposition of the valve. Two of these valves have been replaced, 4 and 13 months after surgery Histopathology of these valves shows normal and living structures.

3. Autologous Fascia Lata for Heart Valve Replacement: Technique and Results

Marian L. Ionescu,* Leeds, England, and

Donald N. Ross,* London, England

Sponsored by Dwight G. McGoon

Heart valves made of fresh autologous fascia lata attached to a supporting frame are used for mitral, aortic and tricuspid replacement. The technique of preparing and inserting the grafts is described. Since April 1969, 100 patients have had one or several heart valves replaced with autologous fascia lata grafts. Except five, all patients were class III and IV before surgery. Of the total of 100 patients (9 to 73 years old) 12 died in the postoperative period of causes not related to the graft. 88 patients are alive and much improved. Thrombo-embolic complications have been completely absent although anticoagulants were not used. So far there have been no graft failures or late complications. Data concerning follow-up studies is presented to evaluate the results (clinical condition, catheter findings, angiography). Data concerning the structure and function of fascia is presented and the experimental and clinical uses of fascia in extracardiac and cardiac surgery are reviewed. The use of autologous, living fascia lata valves is considered to be a better approach for heart valve replacement because autovital fascia maintains its structure unchanged after transplantation, and being under mechanical stimulation it retains its functional properties.

4. A New Central Flow Tilting Disc Valve Prosthesis: One Year Clinical Experience

V. O. Bjork, Stockholm, Sweden

This aortic valve consists of a uniquely suspended free floating disc and a stellite cage (manufactured by Shiley Laboratories). The disc tilts 60° about an imaginary hinge, providing central flow. The pivot point of the disc shifts towards the center as the disc closes, greatly reducing closing impact velocity. The extreme low mass inertia of the disc contributes to the effectiveness of the valve, especially at high pulse rates. The disc is made of a thermoplastic material (acetal recin), which has the highest fatigue endurance limits and the highest abrasion resistance of any commercial thermoplastic. Accelerated pulse duplicator tests show that projected wear limits will easily exceed thirty years. Significantly lower gradients have been obtained, which is important in cases involving a narrow aortic root and calcine aortic stenosis. Blood trauma has been reduced to a minimum as well by the low gradient as by the fact that the disc does not hit the ring during diastole. In the first 45 cases operated there were 6 deaths. The mean systolic peak gradient at the end of the operation was 5.8 mm Hg. There was no significant regurgitation or hemolysis. Follow-up to one year has given excellent results.

5. Pectus Excavatum: A 20 Year Surgical Experience

J. Alex Haller, Jr.,George N. Peters,* Mark M. Ravitch,

David Mazur,* and J. J. White,* Baltimore, Md.

Surgical correction of pectus excavatum was performed in 166 children at the Johns Hopkins Hospital in the years 1949 through 1968. The two major indications for surgical reconstruction were cosmetic restoration of the anterior thorax and prevention of serious postural deformity. A basic operative procedure consisting of cartilage excision, sternal fracture and tripod stabilization without internal or external fixation was used in almost all cases. Several technical modifications of the operation have been introduced through the years. This series of patients was evaluated to determine the immediate morbidity and mortality and the long-term adequacy of the repair. Significant postoperative complications occurred in 5% and included mediastinal infections and wound separations. Except for these rare complications the postoperative morbidity in 95% was unremarkable. Long-term follow-up of these patients was accomplished in 92 cases with an average time of 8.25 years. The vast majority of patients and parents were pleased with their operative results and these were considered satisfactory by the examining physicians. Late partial recurrences were noted in 11%. A secondary operative correction was performed in 7% with satisfactory results. There were no deaths in the series. Our current approach to pectus excavatum including indications for surgery, technical features of the operative repair, management of complications and long-term results will be discussed in detail.

6. Current Surgical Management of Pulmonary Tuberculosis

Wilford B. Neptune, Samuel Kim,* and John Bookwalter,*

Boston, Mass.

In the past five years, 168 patients had surgery for pulmonary tuberculosis at the Norfolk County Tuberculosis Hospital Twenty-nine were readmission cases and 35 had previously had surgery. The indications for surgery varied but were primarily persistent cavity in 94 patients Seventeen patients had drug resistant organisms, eight had diabetes; 20 had chronic alcoholism; and 16 had cardiac disease. There was only one postoperative death, no empyemas, no bronchopleural fistulas and no spread of disease. There were two late deaths unrelated to tuberculosis. All other patients had control of disease and were discharged. One patient was readmitted with reactivation after erroneously stopping drug therapy seven months following a pulmonary resection. Although statistics are favorable with drug therapy there are still patients with either uncontrolled disease or residual lesions with a poor prognosis. Surgery may favorably alter the immediate problem and offer future security. In any surgical program, however, the morbidity and mortality should be minimal, outcome should be predictable, and control of disease should be enhanced. A review of the indications, surgical procedures, and follow-up will be presented.

7. Surgical Therapy in Neonatal Air Block Syndrome

Jay L. Grosfeld,* H. William Clatworthy, Jr , and

Thomas R. Frye,* Columbus, Ohio

An experience with 179 newborn infants with air block syndrome is presented to evaluate mortality in relation to therapy and suggest a plan of management. Pneumothorax occurred alone or in combination with interstitial emphysema, pneumomediastinum, or pneumopencardium in 127 cases. Pneumothorax was unilateral in 96 patients and bilateral in 31. Interstitial emphysema occurred alone in 19 infants and with pneumomediastinum in 33. Therapy consisted of observation alone in 121 patients, needle aspiration in two, and tube thoracostomy in 56. The overall mortality rate was 32.9%: 50% in bilateral pneumothorax, and 26% in unilateral pneumothorax. The mortality rate in the observed pneumothorax group and the tube treated group was similar (33%). Patients with unilateral pneumothorax or pneumomediastinum had a significantly lower (26%) mortality than cases of interstitial emphysema alone (50%). Air piercing the pleura appears to "protect" the infant's lung. Tube thoracostomy is recommended only in cases of tension pneumothorax, and in a deteriorating infant with partially collapsed lung due to loss of lung compliance from excessive interstitial emphysema. Careful selection of patients for tube thoracostomy, close monitoring of pH and blood gas measurements, serial chest x-rays, and assisted ventilation, when indicated, has diminished the mortality rate from 40% to 15% in the past five years.

8. Comparative Results of Early Internal Stabilization and Other Methods for Treating Flail Chest

Robert F. Wilson,* and S. Sankaran,* Detroit, Mich.

Sponsored by Raymond J. Barrett

Although many physicians now treat flail chest with early internal stabilization using tracheostomy and mechanical ventilators, there is little or no evidence that this method has significantly improved survival rates In an attempt to more clearly define the benefits to be derived from early internal stabilization, a series of 89 patients with flail chest seen from January 1962 through July 1969 were reviewed. The treatment given during the first 48 hours was "none" in 7 patients, external traction in 9, tracheostomy in 9, tracheostomy and external traction in 25, and tracheostomy and respiration in 39. The mortality rates in these groups were 52%, 0, 22%, 32%, and 23% respectively. These figures m themselves, however, are somewhat deceptive. Of 59 patients with relatively uncomplicated flail chest injuries, only 6 (10%) died. Of the 9 with severe associated injuries, all 9 (100%) died. Although the type of treatment used made little or no difference in the above 2 groups, it was extremely important in the other 21 patients with injuries of intermediate severity Of 9 patients treated with early tracheostomy and respirator assistance, only 1 (11%) died Of the 12 treated differently, 8 (67%) died. This difference was statistically significant (P<0.02).

9. A Case of Clinical Lung Allotransplantation

James D. Hardy, Fikri Alican,* P. Moynihan,* H. Timmis,

C Chavez,* J. T. Davis,* P. Anas,* and L. Fabian,*

Jackson, Miss.

This 66 year old man with chronic obstructive pulmonary emphysema had a Pco₂ of 80 mmHg and a Po₂ of up to 90 mmHg on the respirator but usually around 40 mmHg. He was admitted to our hospital on three previous occasions during the year 1968 with acute bronchitis and respiratory distress. When last admitted he was almost moribund and CO₂ narcosis and hypoxia kept him somnolent. A light growth of E. coli and pseudomonas were present in his sputum. Following resuscitation and when the infection was cleared, the left lung of a cadaver was transplanted in January 1969. A catheter was left in the left pulmonary vein to measure function. Arterial blood gas values steadily improved over the weeks. At two weeks pulmonary arteriogram and lung scan were normal His general condition was satisfactory until the 24th day when he abruptly developed pseudomonas pneumonitis in his right lung and expired on the 29th day. Autopsy showed that the transplanted lung had not been rejected. A detailed study of this case, a review of our 1963 case, a survey of the world's experience, and the special problems of clinical lung transplantation will be presented.

*By Invitation