American Association for

Thoracic Surgery

57th Annual Meeting

Scientific Program

MONDAY MORNING, APRIL 18, 1977

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

Grand Ballroom

8:45 A.M. Scientific Session

Grand Ballroom

1. Selective Surgical Management in Infants with Esopha-geal Atresia Based Upon Clinical Status

JUDSON G. RANDOLPH, R. PETER ALTMAN* and

KATHRYN D. ANDERSON*, Washington, D.C.

Fifty-six patients with esophageal atresia and distal tracheo-esophageal fistula (Vogt-Gross Type C) have been treated at our institution since 1966. The methods of treatment have been individualized based upon the following criteria: (a) gestational age, (b) birth weight, (c) pulmonary status, and (d) coexistence of other major anomalies. Three distinct approaches have evolved:

I. Immediate Primary Repair; reserved for infants weighing more than 2 Kg., with no major anomalies and satisfactory pulmonary status.

II. Delayed Primary Repair; infants of adequate weight (greater than 2,000 gm.) showing significant but reversible pulmonary changes with anticipated recovery within 1 week, and infants requiring several days for evaluation of an associated congenital anomaly. Temporize by upper pouch suction, gastrostomy, and antibiotics.

III. Staged Repair; premature and severely distressed infants as well as those with cardiac lesions of surgical priority; staging consists of upper pouch suction, gastrostomy, retropleural division of fistula, or gastric division, with subsequent transpleural repair in 4 to 8 weeks.

The surgical approach to each of these infants has been selected after assessment of all aspects of their clinical condition. Flexibility in treatment which is predicated on previously established criteria, seems superior to any single surgical plan.

*By invitation

2. Resection of Left Ventricular Outflow Obstruction in D-Transposition of the Great Arteries

F. S. IDRISS, S. DE LEON*, H. NIKAIDOH*, M. A. PAUL*,

E. NEWFELD* and A. J. MUSTER*, Chicago, Illinois

Left ventricular (LV) outflow obstruction in d-transposition of the great arteries (TGA) may complicate surgical management. Two operative techniques can be used; direct resection of the obstruction or redirecting the flow with a Rastelli operation when a VSD is present. Of 110 patients who underwent correction of TGA by intra-atrial venous switch (Mustard), there were 22 patients who had significant LV outflow stenosis with or without VSD. Preoperatively, the LV to pulmonary artery peak systolic pressure gradient (LVPAG) in 20 patients ranged from 40 to 92 (average 67) mm Hg. Age at surgery ranged from 5 mo. to 18 yrs.; 18 had subpulmonic, 2 valvar and 2 supravalvar stenosis. VSD was present in 14, PDA in 5 and mitral stenosis in 1; 3 patients had a previous Baffes procedure, 2 Waterston-Cooley anastomosis, 1 Blalock-Taussig shunt, 2 surgical atrial septectomy and 1 Glenn procedure.

The pulmonic and subpulmonic areas were usually approached through the pulmonary artery during a short period of hypothermia and circulatory arrest after placing the intra-atrial baffle and closing the VSD. In few patients resection was accomplished through the VSD. There were 3 hospital deaths; the remaining patients are doing well. Two patients sustained complete A-V block and have a permanent cardiac pacemaker. Cardiac catheterization 1 to 5 years after surgery in 13 patients showed a significant decrease in the LVPAG in 11 patients. The preoperative average gradient of 67 (40 to 92) mm Hg was reduced to an average of 23 (0 to 58) mm Hg. In one patient with intact ventricular septum there was no change and in one an increase in the pressure gradient; 75 mm Hg preoperative, 110 mm Hg postoperative.

Our experience with these 22 patients demonstrates that direct resection of LV outflow stenosis in TGA in conjunction with a Mustard procedure and closure of the VSD when present can be accomplished with satisfactory results and adequate relief of the LV outflow obstruction.

*By invitation

3. Discrete Subvalvular Aortic Stenosis - An Evaluation of Operative Therapy

ROBERT L. HARDESTY*, HARTLEY P. GRIFFITH*,

ROBERT A. MATTHEWS*, RALPH D. SIEWERS*,

JAMES R. ZUBERBUHLER* and HENRY T. BAHNSON,

Pittsburgh, Pennsylvania

Thirty-five children (median age of seven years) with discrete subvalvular aortic stenosis underwent operative treatment between 1962 and 1975. The three anatomic types of obstruction encountered were the thin membrane (21 cases), the fibromuscular collar (13 cases), and the fibromuscular tunnel (1 case). Valvular stenosis was associated with the thin membrane in six patients and with the fibromuscular collar in two. A second operation was performed for what was either an inadequate resection or regrowth of the subvalvular fibrous tissue in two instances and for an unrecognized membrane in a child who had previously undergone an aortic commissurotomy. The median gradient preoperatively was 80 Torr.

Three operative deaths occurred (9%). One death occurred three years post-operatively and was due to a malfunctioning pacemaker - the only complete heart block in the series. All the children have been re-evaluated periodically. Clinical electrocardiographic, and roentgenographic evaluations indicate that symptoms have been relieved (3 cases), left ventricular hypertrophy has diminished (30 cases), and aortic insufficiency has remained the same as it was preoperatively (15 cases). One patient has mild mitral insufficiency caused by the resection. No iatrogenic ventricular septal defect has occurred.

*By invitation

4. Supravalvular Aortic Stenosis - Repair by Extended Aortoplasty

DONALD B. DOTY, DONALD B. POLANSKY* and

CONRAD B. JENSON*, Iowa City, Iowa and Salt Lake City, Utah

Enlargement of the aorta by diamond shaped patch of the noncoronary sinus of Valsalva may not be sufficient in severe cases of supravalvular aortic stenosis. This traditional reconstruction is asymmetric and if the fibrous supravalvular ring is thick and rigid, the aorta may not open widely with patch angioplasty so that aortic obstruction may remain as shown in cross section A. Also, aortic valve function may not be perfect after asymmetric reconstruction, so there may be aortic valve incompetence or obstruction of coronary ostia by the valve cusps.

A new reconstructive operation was designed and used in 8 patients. All survived and are asymptomatic. The aortoplasty was extended so that the supravavular ring was incised at two points in the noncoronary and in the right coronary sinus of Valsalva. The area of stenosis was widely opened, and the cusps of the aortic valve lengthened, providing better approximation and function. A tubular dacron prosthesis, tailored to reconstruct the aorta, provided a wide aortic cross sectional area, as shown in B.

Better understanding of the details of surgical anatomy of supravalvular aortic stenosis and a technique - extended aortoplasty - for symmetric reconstruction of the aorta have provided more predictable relief of aortic obstruction and improved function of the aortic valve.

INTERMISSION - VISIT EXHIBITS

*By invitation

5. Repair of Tetralogy of Fallot in Infancy

ALDO R. CASTANEDA and WILLIAM I. NORWOOD*,

Boston, Massachusetts

Thirty-five infants, ranging in age from 12 days to 1 year (mean age 4 months) had repair of tetralogy of Fallot using deep hypothermic circulatory arrest. Two of these infants had a congenitally absent left pulmonary artery and one had an aorto-pulmonary window. Thirty-one required a right ventricular outflow (RVO) patch; in 29 the patch extended across the pulmonary valve annulus. All had patch closure of the ventricular septal defect (VSD); in one infant a perforated patch was used because of severe hypoplasia of both pulmonary arteries. Hospital mortality was 5% (2 patients). There were no late deaths. Transient complete heart block occurred in one, and right bundle branch block with left anterior hemi-block persisted one year after surgery in another patient. Cardiac output (Pick or thermodilution) and intracavitary pressures were obtained after surgery in all patients. So far, 18 patients had one year postoperative catheterization studies. Two infants, who had no RVO patch (done early in this series), had residual RVO gradients of 70 mm Hg, and also developed right ventricular aneurysms. Both of these patients, and another infant with a residual VSD (>2:1) have been successfully reoperated. We conclude that the hospital mortality and the late results justify our continued evaluation of primary repair of tetralogy of Fallot in symptomatic infants, regardless of weight or age. Our present contraindication to reparative surgery in infancy is an anterior descending coronary artery arising from the right coronary artery.

*By invitation

6. Primary Patch-Enlargement of the Pulmonary Valve Ring in the Repair of the Tetralogy of Fallot

ALBERT D. PACIFICO, JOHN W. KIRKLIN and

EUGENE H. BLACKSTONE*, Birmingham, Alabama

A precise way of identifying during the repair (rather than by pressure measurements immediately after repair) the patients with tetralogy of Fallot who require patch-enlargement of the pulmonary valve ring was sought by using a protocol for this in 54 consecutive patients during a 12 month period (May 1,1975 to May 1, 1976). When the ring diameter (mm) measured after pulmonary valvotomy was less than a "minimum acceptable" value from a table generated by us of this according to the patient's weight (kilograms), the ring was enlarged primarily by patch enlargement; otherwise, only the short vertical incision in the infundibulum was closed with a patch. Thirty-two patients did not receive primary graft enlargement of the valve ring (Group 1) and 22 patients did; in two patients of Group 1, patch enlargement was placed secondarily after measuring pressures. Primary enlargement was used in 4 (40%) of 10 patients ≤ l year of age,13 (50.0%) of 26 >l ≤ 4, and 7 (38.9%) of 18 > 4. The ratio of systolic right over left ventricular pressure (systolic P_RV/LV)measured in the operating room was a mean of 0.46 ± .135 (1 SD) for patients receiving patch-enlargement of the ring.

Systolic P_RV/LV immediately after repair in Group 1, without patch-enlargement of the ring was 0.37 ± .140 (in all 13 patients it was ≤ 0.65) when the valve ring was normal or larger, according to the normal values for weight of Rowlatt, Rimoldi, and Lev; it was 0.47 ± .136 (in 11 of 12 patients it was ≤ 0.65) when the diameter was less than normal but within its 50% confidence limits; it was 0.60 ± 0.86 (in 2 of 3 patients it was ≤ 0.65) when smaller but within the 72.5% confidence limits; and it was 0.74 ± .215 (in 2 of 4 patients it was ≤ 0.65) when smaller than the 95% confidence limits.

We conclude that relating the patient's valve ring diameter to the data of Rowlatt, Rimoldi, and Lev allows the surgeon during the repair to determine the probability that patch enlargement of the valve ring is necessary for achieving a satisfactory post-repair systolic P_RV/LV.

11:15 A.M. Presidential Address

OUR OBLIGATION TO DEVELOPING NATIONS

Henry T. Bahnson

*By invitation