Wednesday Morning, May 9, 1984

WEDNESDAY MORNING, May 9, 1984

8:30 a.m. Scientific Session - Grand Ballroom - Third Floor

29. Surgical Assessment of Percutaneous Balloon Pulmonary and Aortic Valvuloplasty

JOSEPH T. WALLS*, ZUHDI LABABIDI*,

JACK CURTIS*, and DONALD SILVER

Columbia, Missouri

Results of percutaneous balloon pulmonary valvuloplasty (PBPV) and percutaneous balloon aortic valvuloplasty (PBAV) for reflief of valvular pulmonic stenosis (PS) and valvular aortic stenosis (AS) were assessed in 56 patients. Thirty had PS and 26 had AS. Patients with PS had reduction in peak systolic valve gradient (G) from 85 ±36 mmHg to 27 ± 17 mmHg (p<0.01). Seven patients were later treated with open valvulotomy. Four of 5 patients with complex cardiac anomalies and PS had reduction in G following PBPV; one did not. Examination of the pulmonary valve at operation revealed 3 mechanisms of PBPV relief of PS (1) commissural splitting (2) cusp tearing (3) cusp avulsion from the anulus. All patients with cusp avulsion had infundibular stenosis. PBAV in 26 patients with AS reduced G from 113 ± 45 mmHg to 32 ± 17 mmHg (p<0.01). Mild aortic valve regurgitation occurred in 10 patients. Two patients were later treated by open aortic valvulotomy. One had evidence of valve stretching and one had a commissure partially opened by PBAV.

Conclusion: PBPV and PBAV can relieve G of PS and AS. Over-distention of the valve anulus must be avoided to reduce the possibility of extensive cusp avulsion and severe regurgitation. At present we do not recommend PBPV in patients who have PS and infundibular stenosis due to increased incidence of cusp avulsion. Anatomic results are less predictable than open valvulotomy using cardiopulmonary bypass, however, the effects may be similar to closed operative techniques. No deaths occurred.

*By Invitation

30. Should Elective Repair of Coarctation of the Aorta Be Done In Infancy?

DAVID B. CAMPBELL*, JOHN A. WALDHAUSEN

and WILLIAM S. PIERCE

Hershey, Pennsylvania

Our experience with CoA in infants and the subclavian flap repair over the past ten years includes 51 patients under one year of age. In the group of 34 patients under one month of age at the time of operation, all but two had an associated PDA, and 22 (65%) had associated intracardiac anomalies. All neonates presented with severe congestive heart failure and operation was carried out promptly after stabilization with inotropic agents and diuretics. Prostaglandin infusions have been essential in the care of many of these infants. Operative mortality was two of 51 patients (4%). No patient more than four days old has died. Concomitant pulmonary artery banding was performed in five infants with no deaths. Twenty-one infants were repaired with running nonabsorbable suture, 22 with interrupted nonabsorbable suture, and the last eight have had continuous monofilament absorbable suture used. Mean follow-ups has been 42 months. Nine patients have been restudied invasively, revealing residual gradients (5, 15, 20 mm Hg) in three continuous repairs. The other six all had interrupted repairs and no gradient was present. Initial follow-up information for the group with absorbable suture repair suggests no residual gradients. No patient had significant upper extremity or hand morbidity. Ten patients have shown normal exercise responses (blood pressure and arm to leg gradients).

In the absence of absorbable vascular suture, an interrupted suture technique is superior to continuous running repair. In view of the low operative mortality, the excellent growth of the repaired area, and concern regarding the late development of cardiovascular disease (especially hypertension) if repair is effected in childhood or adolescence, we favor subclavian flap repair of CoA, in all infants <2 years of age with or without symptoms. Concomitant pulmonary artery banding is seldom indicated.

*By Invitation

31. The Mustard Operation for Simple and Complex Forms of d-Transposition: Early and Late Results

WILLIAM A. GAY, JR., JOHN E. O'LAUGHLIN*

and MARY ALLEN ENGLE*

New York, New York

Between Jan. 1972 and Nov. 1983, 112 children had operative repair of d-Transposition of the Great Arteries (d-TGA) using the interatrial baffle technique (Mustard) or a modification thereof. 73 operations (Group I) were done prior to 1977 and the 66 survivors formed the base for reporting late results. The remaining 39 (Group II) were done within the past five years and form the base for reporting early results. Complex d-TGA (associated VSD and/or PS) was present in 20 to 25% of both groups.

Operative mortality was 9.6% (7/73) in Grp I and 7.7% (3/39) in Grp II. There were four late deaths in Grp I (5.5%) at 1, 4, 5, and 10 years postop. 85% of the original group survived and enjoys virtually full activity. The majority of children with simple forms of d-TGA have required operative repair between 3 and 6 months of age. Those with more complex forms, because mixing is usually adequate and pulmonary blood flow may not be excessive, may be able to have their operation later.

Although atrial or junctional rhythm is present in 9 of the Group I patients the majority have a sinus-like rhythm. There has been no complete heart block. The most troublesome sequel of the operation has been superior caval obstruction with edema of the face and upper extremities in the early postoperative period. In most patients elevation of the head of the bed has resulted in complete resolution. Obstruction to pulmonary venous inflow has been seen in only two patients, the only two to have Dacron used as the baffle material instead of pericardium. Malfunction of the tricuspid valve and/or right ventricular failure has been seen in only two patients. In both of these a VSD had been repaired through the tricuspid valve inferring intra-operative injury. The feared development of right ventricular failure and tricuspid regurgitation as a long-term consequence of making the right ventricle the systemic pump has not materialized. Recent technical modifications may result in lessening the incidence of caval stenosis/obstruction.

Although the arterial switch operation described by Jatene and the utilization of right atrial wall to shift caval inflow as described by Senning both present attractive features, the acceptable short and long-term results of the Mustard operation have made us hesitant to abandon it as our primary means of surgical repair of d-TGA.

*By Invitation

32. Experience With The Fontan Procedure

HILLEL LAKS, JEFFREY C. MILLIKEN*,

JOSEPH K. PERLOFF*, WILLIAM HELLENBRAND*,

BARBARA GEORGE*, ALVIN CHIN*,

THOMAS DISESSA * and ROBERTA WILLIAM*

Los Angeles, California and New Haven Connecticut

From 1975 to 1983, 32 patients (17 male and 15 female) have undergone the Fontan procedure, aged 2-38 years (mean 13 years). Sixteen had tricuspid atresia, 14 univentricular heart, and 2 pulmonary atresia with hypoplastic right ventricle (RV). Thirteen underwent right atrial (RA) to RV connections; in 8 with valved (V) and 5 without. Nineteen underwent RA to pulmonary artery (PA) connections, in 7 with V and 12 without V. There were 2 early (<30 days) deaths (6%) from venous hypertension in one, and delayed tamponade in one. Eight were treated with compressive venous assistance immediately postoperatively. The lower extremities and abdomen were placed in a mass suit and compressed at 30-45 mmHg for 30-45 seconds of the minute. This resulted in an elevation in right and left atrial and systemic blood pressure in all. In four with low output and large volume requirements, the assist device improved cardiac output and mobilized extravascular fluid. There were two late deaths, both with venous hypertension and one with conduit thrombosis. Doppler flow patterns in 8 patients showed biphasic flow in the PA regardless of the type of connection or anatomic diagnosis. Repeat catheterization in 10 patients showed no gradients. Reduced response to exercise was noted in 6 patients with marked elevation in RA pressure and little increase in cardiac output. There was no significant hemodynamic difference in the pressure relative to the type of connection used, the presence of a valve in the connection, or the anatomic diagnosis. As a group however, the RA to RV connections had a lower RA pressure and the univentricular hearts, a higher RA pressure. All survivors remain clinically improved a mean of 4 years postoperatively.

Conclusion: This experience confirms that the Fontan procedure is an effective therapy for carefully selected patients with tricuspid atresia and other complex lesions. The choice of connection, the use of a valve, and the anatomic diagnosis has little effect on postoperative hemodynamics or function, whereas the pulmonary vascular resistance and left ventricular function is critical to a good result. Although the response to exercise is abnormal, the majority of patients have an excellent functional result.

10:00 a.m. Intermission - Visit Exhibits - Second Floor

Complimentary Coffee

*By Invitation

10:45 a.m. Forum Session - Grand Ballroom - Third Floor

33. Targeted Cyclosporine Dose for Cardiac Transplantation: Effect on Rejection and Toxicity

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

ALFREDO TRENTO*, ANN LEE*

and HENRY T. BAHNSON

Pittsburgh, Pennsylvania

A cumulative 16 month >80% survival has been achieved in 34 heart transplant recipients treated with cyclosporine, low maintenance dose pred-nisone and rescue antithymocyte globulin. The administered dose of cyclosporine has been targeted to a whole blood trough level of 1000 ng/ml as measured by radioimmunoassay (Sandoz). If the serum creatinine was elevated (>1.5 mg%), a lower level was sought. When a higher level (1000-1500 ng/ml) was tolerated, as judged by the absence of renal toxicity, it was not reduced if there was evidence of rejection, but a higher level was not sought solely to treat rejection. A lower level (<500 ng/ml) was sought in the management of lymphoproliferative disease (2 patients).

The gradation of histologic rejection (0-4) has been assessed relative to blood levels (<500, 500-1000, and >1000 ng/ml. The average grade of rejection determined by weekly biopsies obtained during the initial hospitalization (4-8 weeks) was similar at whole blood levels of 500-1000 ng/ml (2.2) and at levels greater than 1000 ng/ml (2.3). Interestingly, those patients with levels less than 500 ng/ml had an average grade of rejection of only 1.2. The administered oral dose averaged 5.8 mg/kg, 7.8 mg/kg, and 8.2 mg/kg to achieve the incremental levels. A whole blood level of less than 500 ng/ml was associated with a lower serum creatinine (0.48 mg%) compared to a level of 500-1000 ng/ml (1.6 mg%) and greater than 1000 ng/ml (1.1 mg%). Hepatic toxicity (bilirubin 3.2 mg%) was noted at the level > 1000 ng/ml. In 2 patients, a lymphoproliferative syndrome resolved when the levels were reduced below 500 ng/ml.

In conclusion, whereas high levels of cyclosporine are associated with more toxicity, rejection has been independent of the levels achieved by our protocol.

*By Invitation

34. A New Myofascial Flap: Vascular Conduit Designed for Growth

EDWARDS. YEE*, SCOTT REPLOGLE*.

YEE-PHONG CHANG* and PAUL A. EBERT

San Francisco, California

The current usage of pulmonary artery conduits have greatly altered the fatal outcome of many congenital heart lesions. However, their severe limitations have been tissue ingrowth of the synthetic lumen, lack of enlargement with time, and the distortion of the native tissue. Autogenous tissue with pericardium have shown aneurysmal changes. To test the feasibility of the autogenous fascial tissue for (1) patency, (2) potential growth, (3) prevention of distortion of normal vessels, two types of myofascial flaps were designed based on current microvascular and flap rotation techniques. Twenty beagle puppies (4 weeks old) underwent replacement of the left pulmonary artery by either Group I-patch angioplasty or Group II-circumferential tube graft. The flap designed was based on the rectus muscle and its adjacent fascial tissue with preservation of the pedicle base and its blood supply from the internal mammary artery (IMA). This constructed conduit was rotated into the thoracic cavity for replacement of small puppy pulmonary artery (6-8mm).

Results: Angiographically at 18 months no pulmonary artery occlusions, distortions or aneurysms were encountered. Both groups I & II exhibited similar growth patterns at the 6 months time intervals. While the internal mammary artery patency rate was only 25%, long term growth was best seen in these conduits (left to right pulmonary artery diameter ratio = 0.88 ± 0.11).

Groups I & II	6 Mos	.89 ± .05	18 Mos	0.60 ± 0.14*
Patent IMA	6 Mos	.85 ± .04	18 Mos	0.88 ± 0.11
*p = 0.05

Conclusions: (1) The rectus fascial flap design is nonthrombogentic which exhibits no tissue overgrowth, distortion, or aneurysm and can serve as a patent conduit even in a diminutive small low pressure system. (2) The growth of this tissue flap is dependent on the patency of its blood supply.

*By Invitation

35. Amelioration of the Deleterious Effects of Platelets Activated During Cariopulmonary Bypass: Comparison of a Thromboxane Synthetase Inhibitor and a Prostacyclin Analogue

CHARLES B. HUDDLESTON*,

JOHN W. MAMMON, JR.*, THOMAS H. WAREING*,

FLAVIAN M. LUPINETTI*, JEFFREY A. CLANTON*,

JERRY C. COLLINS* and HARVEY W. BENDER, JR.

Nashville, Tennessee

Thrombocytopenia and platelet dysfunction are commonly seen following cardiopulmonary bypass in part as a result of the contact of platelets on the surfaces of the oxygenator. Further, the microvascular bed of the ischemic myocardium is a potent stimulus for platelet deposition and microvascular plugging. Thus, it would appear theoretically advantageous to provide phar-macologic protection of platelets by inhibiting their response to activating agents thereby preventing their loss into the extra-corporeal circuit and also the deleterious effects of myocardial platelet deposition. To study this further, 21 mongrel dogs were placed on cardiopulmonary bypass with 30 minutes of normothermic global ischemia. They were randomly assigned to receive pretreatment with an infusion of either saline (control, n = 8), a thromboxane synthetase inhibitor (RO-22-4679, n = 5), or a prostacyclin analogue which does not lower blood pressure (ZK 36,374, n = 8). Following global ischemia, the animals were supported with cardiopulmonary bypass for 30 minutes, weaned and separated, then sacrificed 60 minutes later. Comparisons among the groups were made on the basis of blood platelet counts, myocardial blood flow (using radioactive microspheres), and myocardial platelet deposition (using ¹¹¹Indium-labelled platelets). Results (mean ± SEM, *p < .01 vs. control):

GROUP	Platelet Count (X10³)				LV Platelet Deposition				(Ratio of Tissue ¹¹¹In: Blood ¹¹¹In)
	Baseline		Post-CPB		Endocardium		Epicardium
Control	250.4 ± 20.7		69.7 ± 10.6		0.124 ± 0.027		0.122 ± 0.021
RO-22-4679	265.3± 51.9		92.8 ± 14.8		0.087 ± 0.011		0.096 ± 0.010		LV = Left Ventricle
ZK 36,374	250.4 ± 35.8		102.8 ± 10.7*		0.045 ± 0.002*		0.043 ± 0.002*		CPB = Cardiopulmonary Bypass

	Hematocrit				Myocardial Blood Flow (ml/min/gram)
					Endocarium			Epicardium
	Baseline	Post -CPB		Baseline		Post-CPB		Baseline		Post-CPB
Control	47.3 ± 3.5	24.5 ± 2.9		0.68 ± 0.07		0.49 ± 0.14		0.64 ± 0.06		0.60 ± 0.18
RO-22-4679	44.8 ± 1.7	25.5 ± 2.4		0.89 ± 0.10		1.04 ± 0.12*		0.75 ± 0.11		1.14 ± 0.11*
ZK 36,374	37.4 ± 2. 2	24.6 ± 1.5		0.72 ± 0.08		1.28 ± 0.15*		0.74 ± 0.10		1.70 ± 0.21*

We conclude that ZK 36,374 prevents platelet consumption during cardiopulmonary bypass over and above that seen with inhibition of thromboxane synthesis alone. It also prevents deposition of platelets into the myocardium following global ischemia and we presume by that mechanism increases myocardial blood flow.

*By Invitation

36. Pulmonary Circulatory Support: A Quantitative Comparison of Four Methods

WAYNE E. GAINES*, WILLIAM S. PIERCE,

G. ALLEN PROPHET* and KAY L. HOLTZMAN*

Hershey, Pennsylvania

Various innovative methods of pulmonary circulatory support have been recently introduced; however, no quantitative comparison of these methods has been reported. Profound right ventricular failure (RVF) was produced in 16 healthy goats by inducing ventricular fibrillation after the systemic circulation was supported with a pneumatic pulsatile left atrial (LA) to aorta bypass pump. Right atrial (RA) pressure was adjusted to 18 ± 3 mm Hg; blood pH, pCO₂, pO₂ and temperature were controlled. Four methods of providing pulmonary blood flow were evaluated in each animal.

Method of Providing Pulmonary Blood Flow	C.I. (ml/min/kg)	LA Pressure (mm Hg)	RA Pressure (mm Hg)
Passive Flow Through The Pulmonary Artery (PA) due to RA to LA pressure gradient	31.1 ± 12.9	0 ± 6	18 ± 3
Pulmonary Artery Pulsation (PAP) via a 40 ml intra-aortic balloon (IAB) within a 20 mm Dacron graft anastomosed to the main PA	44.4 ± 13.6	3 ± 5	18 ± 3
PAP via a 65 ml single port valveless sac pulsatile assist device	64.3 ± 16.9	5 ± 3	17 ± 4
RA to PA Bypass via a valved pneumatic pulsatile sac type pump	102.0 ± 20.7	14 ± 5	12 ± 3

Passive PA flow alone provided inadequate pulmonary circulatory support. Addition of PAP via the IAB-conduit system increased C.I. 45% above passive PA flow (p<0.0005). However, the C.I. remained inadequate. Increasing PAP volume with a 65 ml sac device provided an additional 65% increase in C.I. (p<0.0005) to a level that is marginally adequate. The valved RA to PA bypass pump increased C.I. 228% of PA passive flow (p<0.0005) to a satisfactory level and is the recommended method of pulmonary circulatory support in profound RVF.

*By Invitation

37. Cardiac Prostacyclin Kinetics During Surgical Cardioplegia

GEORG S. KOBINIA**, PAUL L. LaRAIA*,

MYRON B. PETERSON*, MICHAEL N. D'AMBRA*,

WALTER D. WATKINS*, MORTIMER J. BUCKLEY

and W. GERALD AUSTEN

Boston, Massachusetts

Prostacyclin (PgI2) is a very potent vasodilator and platelet antiag-gregating hormone. Despite the marked systemic changes in PgI2 noted during cariopulmonary bypass (CPBP) and its putative key role in myocardial injury responses, there is little information regarding the cardiac kinetics of PgI2 during surgical cardioplegia (CP). Accordingly, we have evaluated the effect of 30 minutes of hyperkalemic (25 meq potassium), hypothermic (22 degree C.) CP on cardiac PgI2 metabolism in a canine model of standard CPBP. Nine adult mongrel dogs were anesthesized and subjected to standard CPBP utilizing a BOS 5 oxygenator. No donor blood was used during the sterile operative procedures. Samples, drawn from the thoracic aorta (TA), the aortic root (AR) below cross-clamping and the coronary sinus (CS) were taken prior to onset of bypass with all lines in place (A), 25 minutes after partial bypass and cooling down (B), during infusion of initial CP (C), and during infusion of a final CP (D). The stable metabolite of PgI2, 6 keto prostaglandin Fla, was measured by double-antibody radioimmunoassay.

Experimental Period	A	B	C	D
TA	312 (± 46)	845 (± 154)	700 (± 135)	561 (± 101)
AR	-----	-----	112 (± 79)	115 (± 59)
CS	*602 (± 170)	1088 (± 125)	**275(± 57)	**602(± 170)
Results are expressed as mean (±S.D.) pg/ml of 6 keto prostaglandin Fla p<0.03 compared with TA, *p<0.22 compared with AR

These findings support our previous data regarding the increase in systemic PgI2 levels during CPBP. Moreover, they demonstrate that cardiac prostacyclin production occurs during cardiac surgery prior to cardiopulmonary bypass. In addition, our results indicate that substantial cardiac production of PgI2 occurs during hypothermic CP. These findings suggest that the use of pharmacological agents that may nonspecifically inhibit prostaglandin syn-thsis should be avoided during cardiac surgery.

12:00 noon Adjourn for Lunch - Visit Exhibits

*By Invitation

**Current Evarts A. Graham Memorial Traveling Fellow

WEDNESDAY AFTERNOON, May 9, 1984

1:30 p.m. Scientific Session - Grand Ballroom - Third Floor

38. Bronchoscopy After Cardiopulmonary Transplantation

JOHN C. BALDWIN*, STUART W. JAMIESON*,

PHILIP E. OVER*, EDWARD B. STINSON*,

NORMAN E. SHUMWAY and JAMES B.D. MARK

Stanford, California

Fifteen combined heart and lung transplants were performed between March, 1981 and August, 1983. The technical aspects of this operation, including the use of continuous polypropylene anastomoses, has been described. Six of these patients have undergone bronchoscopy at varying intervals after transplantation; five of these procedures were done for specific clinical indications; one was done incidentally during another surgical procedure requiring general anesthesia. We report the endoscopic and pathologic findings in these patients.

All patients had intact, healing tracheal anastomotic suture lines; there were no instances of tracheal stenosis. One patient had minimal granulation tissue along the suture line. The distal tracheobronchial tree appeared endoscopically normal in the transplanted lungs, except in areas of known infiltrates. Four of the patients had endobronchial biopsies, and all showed evidence of chronic inflammation in the submucosa. Eosinophilic pro-teinaceous exudate was noted in the alveolar air spaces in three of the four patients biopsied. No patient was bronchoscoped during a period of cardiac rejection documented by endomyocardial biopsy.

Controversy exists as to the optimal technique for tracheal anastomosis, but in the case of the steroid-treated, immunosuppressed transplant patient, the technique of continuous anastomosis with polypropylene yielded satisfactory results, free of recognized potential complications of early leakage, failure of healing, stenosis, and development of suture-related granulation tissue. Trans-bronchoscopic endobronchial biopsy may not be helpful in diagnosing pulmonary rejection. All patients in this group who were biopsied showed submucosal chronic mononuclear cellular infiltrates, and most had intra-alveolar eosinophilic exudates. These findings were not associated with evidence of cardiac rejection in these patients.

*By Invitation

39. Bronchial Carcinoids: A Review of 111 Cases

BRIAN C. McCAUGHAN*, NAEL MARTINI

and MANJIT S. BAINS*

New York, New York

The medical records of 111 patients with bronchial carcinoids seen between 1949 and 1983 were reviewed. There were 59 females and 52 males. The age range was 12 to 82 years (median 55 years).

Ten of the tumors were incidental pathologic findings at autopsy or surgery. These were excluded from survival data determinations. At the time of diagnosis 87 patients had disease localized to one hemithorax, 14 had distant metastases. The latter were more commonly male and smokers and their tumors had a more malignant histologic appearance compared to the patients with localized disease. Those with distant disease were treated with external radiation and/or chemotherapy and their median survival was 6 months.

Of the 87 with localized disease endobronchial resection was performed in 5 and pulmonary resection in 82 (pneumonectomy 11, bilobectomy 8, lobec-tomy 45, sleeve resection 3, segmentectomy 15). Disease free actuarial survival (Kaplan-Meier) following pulmonary resection was 91% at 5 years and 81% at 10 years. Factors predisposing to recurrence were central location of the tumor, a more malignant histologic appearance and regional lymph node metastases. Disease free survival at 5 and 10 years in 12 patients who had regional lymphatic metastases was 63% and 48% compared with 96% and 88% in those without lymphatic metastases (p = .003).

Complete resection of tumor and involved lymph nodes was associated with long term disease free survival in 4 of these 12 patients. Recurrence following endobronchial resection was observed in 3 of 5 patients.

We conclude that a) carcinoid tumors are malignant and 10% present with metastases and b) for those with clinically localized tumors, the prognosis is determined by the status of the regional lymph nodes which must be assessed at thoracotomy.

*By Invitation

40. Management of Recalcitrant Median Sternotomy Wounds

PETER C. PAIROLERO* and PHILLIP G. ARNOLD*

Rochester, Minnesota

Halifax, Nova Scotia

Although localized endocardial resection (LER) guided by intraoperative mapping has proven superior to simple aneurysmectomy for drug resistant ventricular tachycardia (VT) LER fails to ablate reentrent ventricular arrhythmias in 15 to 20% of patients. Recently, we have employed encircling endocardial resection (EER) with complete removal of endocardial scar in 10 patients without intraoperative mapping. Reproduceable sustained VT was induced in all patients preoperatively with programmed electrical stimulation (PES). PES was performed at twice the diastolic threshold with single and double premature extra stimuli. All 10 patients had failed a trial of conventional antiarrhythmics; 7 patients required frequent cardioversion and 3 patients required overdrive suppression with transvenous pacing. Ejection fraction, estimated by bi-plane angiography, ranged between 20 - 56% (X 31), cardiac index ranged between 1.5 - 2.7 1/m² (X 2.4) and left ventricular end diastolic pressure at rest ranged between 15-32 mmHg (X 22). EER was performed in all patients with complete removal of endocardial scar. EER required reimplantation of the mitral apparatus in 9 patients. 8 patients underwent aneurysmectomy and 9 patients_required concommitant aortocoronary bypass receiving a total of 13 grafts (X 1.3 grafts per patient). There were no spontaneous postoperative arrhythmias. PES was carried out following EER with single, double and triple premature extra stimuli; only 1 patient without postoperative clinical arrhythmias who had required daily preoperative cardioversion had induceable VT with postoperative PES but not after loading with Procainamide. Mean follow-up is 8.9 months. 8 patients are alive and well. There were 2 late deaths. 1 patient died with recurrent ventricular septal defects 2.5 months following extensive septal EER and 1 patient with massive pulmonary embolus and right heart failure at 4 months. This early experience suggests that EER with complete removal of endocardial scar successfully ablates reentrent VT. We feel that EER will prove to be more effective than LER because EER removes all ventricular sites that have the potential to generate reentrent VT. This data also indicates that ventricular septal defects are a potential hazhard of extensive septal endocardial resection and has resulted in the use of a prophylactic septal patch in the last 2 patients.

*By Invitation

42. Cardiac Surgery in Patients with Functioning Renal Allografts

R. MORTON BOLMAN, III*, ROBERT W. ANDERSON,

J. ERNESTO MOLINA, JEFFREY S. SCHWARTZ*,

BARRY LEVINE*, RICHARD L. SIMMONS*

and JOHN S. NAJARIAN*

Minneapolis, Minnesota

The Transplant Service at the University of Minnesota Hospitals has performed nearly 2000 kidney transplants. Fourteen of these patients have developed cardiac conditions necessitating surgical intervention at intervals of 9 to 120 months (average 54 months) following their transplant. These patients had a mean age of 42 years and 5 (36%) were diabetic. All patients had functioning renal allografts with preoperative serum creatinines ranging from 1.0 to 3.2 mg/100 ml (average 1.4 mg/100 ml). All patients were receiving azathioprine and prednisone as their immunosuppressive therapy except two, whose immunosuppression had been discontinued due to life-threatening infection.

Ten patients underwent aorto-coronary saphenous vein bypass grafting (ACBP). One patient underwent two vessel ACBP and concomitant left ventricular aneurysmectomy. Two patients underwent surgery for native valvular endocarditis. One had tricuspid valve debridement for fungal endocarditis, and the other aortic valve replacement (AYR) for bacterial endocarditis. The final patient had calcific aortic stenosis and coronary artery disease (CAD), necessitating AYR and ACBP x 2.

Intraoperative management consisted of routine narcotic anesthesia combined with infusion of a mixture of furosemide in mannitol sufficient to maintain urine output of at least 50-100 ml/hour. Mean arterial pressure was maintained at 70 mmHg or greater during cardiopulmonary bypass to assure adequate perfusion of the renal graft. Myocardial protection consisted of moderate systemic hypothermia (28°C) combined with cold potassium car-dioplegia for periods of ischemia.

Two patients (14%) expired perioperatively. One was a young juvenile onset diabetic with markedly unstable angina who expired suddenly several days after surgery and at autopsy was found to have an occluded right ACBP and extensive infarction. The other was a 51-year-old lady with calcific aortic stenosis and CAD with unstable angina who expired in surgery from uncontrollable arrhythmias. There was one late death (7%) from non-cardiac related causes. The remaining 11 patients are alive and well at intervals of 3 to 82 (mean 25 months) after surgery. Postoperative serum creatinines averaged 1.4 mg/100 ml, unchanged from preoperative levels. Cardiac surgery can be performed safely in patients with functioning renal allografts. Patient survival was acceptable and preservation of renal function was uniformly successful in this group of patients.

*By Invitation

43. Myocardial Surgical Revascularization Following Streptokinase Treatment for Acute Myocardial Infarction

JACQUES GEORGES LOSMAN*,

GUILLERMO C. DACUMOS*,

CHRISTOPHER R. JONES*, DOUGLAS NAGLE*,

ALLAN S. WILENSKY*, R. NEWELL FINCHUM*,

ROBERT G. MARTIN*, MARTIN T. BAILEY*

and DONALD R. KAHN

Birmingham, Alabama

Sixty-one patients (pts) admitted with acute myocardial infarction (MI) were treated with intra-coronary (ICOR, 39 pts) or intravenous (IV, 22 pts) Streptokinase (STR). There were no STR related complications. Group I, 25 ICOR-STR pts and Group II 14, IV-STR pts underwent coronary artery bypass grafting (CABG). Group I included 19 males (ages 40 to 69 years, mean = 54 ± 9) and 6 females (ages 38 to 70 years, mean = 58 ± 11). Admission ECG evidenced antero-lateral MI in 17 pts and inferior MI in 8. Peak CPK ranged from 190 U to 9000 U (mean = 2466 ± 2237, median = 2150). MB fraction ranged from 2% to 46% (mean = 26 ± 11, median = 26). Time from onset of symptoms to ICOR-STR was 290 ± 55 min. Fibrinogen blood levels decreased to 27% of control values 0.61 ± 0.2 mg/L versus 2.23 ± 0.2 mg/L). In 6 pts ICOR-STR failed to re-open the obstructed coronary artery (COR). All 6 developed severe hypokinesia (hypok) in that COR supplied area. Re-canalization occurred in 19 pts, the residual stenosis ranged from 80% to 99%. Severe hypok developed in the supplied area in 4 pts (one apical aneurysm). Five pts developed mild to moderate hypok and 11 (58%) had no myocardial damage. Group II included 12 males (ages 37 to 71, mean = 56 ± 10) and 2 females ages 62 and 72. Admission ECG evidenced antero-lateral Mi's in 4 pts and inferior Mi's in 10 pts. Peak CPK ranged from 230 U to 8100 U (mean = 2187 ± 2008, median = 1700), MB fraction ranged from 1% to 29% (mean = 16% ± 7, median = 15%). Time from onset of symptoms to IV-STR was 163 ± 89 min., with symptoms relieved in 13/14 pts after 43 ± 29 min. In 4 pts IV-STR failed to re-open the COR. Severe hypok of the supplied area developed in 3 (one apical aneurysm), and moderate hypok in one. In 10 pts (71%) IV-STR re-opened the COR. One pt developed severe and 2 pts moderate hypok in the COR supplied area. Group I and II did not differ significantly for any of the parameters analyzed. In Group I, 10 pts (40%) and in Group II, 7 pts (50%), had no evidence of muscle damage on ventriculography or on direct inspection at surgery. CABG (3.3 ± 0.9 graft/pt) were performed without operative or early postoperative mortality. In conclusion, STR appears to be a useful agent to salvage myocardium and JV-STR may be as effective as ICOR-STR. IV-STR has advantages of earlier administration, (p<0.05), no invasive procedure and lesser cost.

3:30 p.m. Adjourn

*By Invitation

WEDNESDAY MORNING, May 9, 1984

Hershey, Pennsylvania

YEE-PHONG CHANG* and PAUL A. EBERT

Post-CPB

Baseline

Stanford, California

Sponsored by: GORDON K. DANIELSON

Halifax, Nova Scotia