MONDAY AFTERNOON, April 27, 1992

1:30 p.m. SCIENTIFIC SESSION - Los Angeles Ballroom

6. Preoperative Prediction for Cardiopulmonary By-Pass in Lung Transplantation

ALBERTO de HOYOS, M.D. *, WILFRED DEMAJO, M.D.*,

TIMOTHY WINTON, M.D.*, GREGORY SNELL, M.D.*,

JOHN MILLER, M.D.*, JANET MA URER, M.D.*

and G. ALEC PATTERSON, M.D.

Toronto, Ontario

Recent innovations in the surgical technique of isolated lung transplantation have made feasible sequential bilateral transplants without car-diopulmonary by-pass (CPB). We analyzed preoperative parameters of car-diopulmonary function that may predict the need for CPB in single (SLT n = 51) and double lung transplant recipients (DLT n = 37). 25/51 SLT and 14/37 DLT required CPB. Of the 14 DLT, 10 required CPB for implantation of both lungs. The other 4 required CPB for the second implant only. The Table depicts preoperative parameters of cardiopulmonary function analyzed, (*p<0.05 CPB vs NCPB). FP = first pass; RV = right ventricular ejection fraction; LV = left ventricular ejection fraction; SMW = six minute walk; PAP = pulmonary artery pressure; PVR = pulmonary vascular resistance. Results are expressed as mean values ± SD.

SLT		RV		LV		SMW
	FP	Rest	EX	Rest	Ex	m
NCPB	34*	34*	34*	59	63	382*
SD	(6)	(11)	(12)	(10)	(11)	(100)
CPB	25	24	24	57	58	266
SD	(7)	(12)	(13)	(10)	(12)	(146)
BLT
NCPB	30	37	38*	57	60	441
SD	(9)	(9)	(8)	(8)	(9)	(161)
CPB	25	33	29	53	58	489
SD	(12)	(7)	(9)	(7)	(9)	(143)
SLT	Pa02	Oz	02 Sat	Exer	PAP	PVR
	mmHg	1/m	%	min	mmHg	d.s.m
NCPB	56*	2.3*	87*	4.6*	35*	235
SD	(9)	(2)	(5)	(2)	(7)	(54)
CPB	39	5	81	3.4	57	743
SD	(12)	(3)	(6)	(2)	(22)	(490)
BLT
NCPB	NA	1.8*	89	5.5	28	286
SD		(1.5)	(3)	(3)	(7)	(90)
CPB	NA	3.3	86	6	28	298
SD		(3)	(5)	(4)	(7)	(106)

SLT's required CPB for increased PAP (n = 12), desaturation (n = 8) and systemic hypotension (n = 5). There was no difference in RV and LV function, SMW, and 0₂ requirements among these groups. 0₂ saturation < 79% during exercise (N = 6) predicted patients requiring CPB for desaturation. Indications for CPB for both lungs in DLT's were prophylactic (n = 3), desaturation (n = 3), increased PAP (n = 3) and technical (n = 1). Indications for CPB for the second implant were ventricular arrhythmias secondary to hyperkalemia and acidosis (n = 3), and systemic hypotension, desaturation and pulmonary hypertension (n = 1). No difference in postoperative complications and operative mortality were seen between CPB and NCPB groups. We conclude that preoperative parameters of RV function, exercise capacity, Pa0₂, oxygen requirements and pulmonary hemodynamics can be utilized to predict SLT who require CPB. In DLT recipients however, the decision to utilize CPB was made intraoperatively based on the level of PAP, desaturation and hemodynamic instability secondary to ventricular arrhythmias.

*By Invitation

7. Heart Transplantation: Changing Patterns in Patient Selection and Costs

KEITH REEMTSMA, M.D., GRETCHEN BERLAND, B.A.*,

JEFFREY MERRILL, DR. P.H.*

RAYMOND R. ARONS, CRAIG EVANS, ESQ., J.D., MBA*,

RONALD E. DRUSIN, M.D.*, CRAIG SMITH M.D.,

and ERIC ROSE, M.D.

New York, New York

Our heart transplant program, now in its fifteenth year, involves experience with 498 recipients, all of whom have been followed with at least annual visits. This report is focused on disturbing trends in our patient selection and costs.

We have been startled to discover that in the last four years the mean hospital cost per transplant in our program has almost tripled. We have looked at possible explanations and have concluded that as our waiting list has increased, we are operating on an increased proportion of the most sick patients.

Between 1988 and 1991, the percentage of ICU-bound patients rose from 34% to 62%. During the same time, the length of stay (LOS) rose from 29.5 days to 44.9 days, and the preoperative length of stay increased from 8.9 to 17.5 days.

We found no significant difference in survival of the ICU-bound versus the other patients at 30 days (90.7 vs 88%), and at one year through 1990 (74.5 vs 75%).

Year	N	%ICU-Bound	LOS-Total	LOS Pretransplant	Cost
1991 (thru 10/14/91)	73	62	44.9	17.5	$129,319
1990	104	47	29.4	4.8	$106,692
1989	79	28	31.3	6.0	$83,703
1988	59	34	29.5	8.9	$50,290

This study documents the trend of sharply rising costs associated with operating on an increasing proportion of the most seriously ill patients. Although survival rates are equivalent in the ICU-bound and the less sick patients, we raise the question of how best to select recipients of these donor organs in limited supply.

*By Invitation

8. Anterior Trans-Cervical Approach for Radical Resection of Lung Tumors Invading the Thoracic Inlet

PHILIPPE G. DARTEVELLE, M.D.*,

ALAIN R. CHAPELIER, M.D.*, GEORGES S. TABET, M.D.*,

BERNARD LENOT, M.D. *, FRANCOIS LE ROY

LADURIE, M.D. * and JACQUES CERRINA, M.D. *

Le Plessis Robinson, France

Sponsored by: Jean DesLauriers, M.D., Quebec

Pulmonary tumors invading the thoracic inlet present a surgical challenge. Through the classical posterior thoracic approach, as described by Paulson, one cannot perform complete resection of the cervical extension of the tumor above the thoracic inlet (Subclavian vessels, Brachial plexus, Scalenus muscles, and Phrenic nerve). Therefore, we describe herein an original anterior transcervical approach which is required for a safe exposure and radical resection of cervical structures.

From 1980 to 1991, 29 patients underwent radical resection of such tumors through this approach (Squamous cell carcinoma n = 11, Adenocar-cinoma n = 9, Large cell carcinoma n = 7, and Mixed cell carcinoma n = 2).

A large L shaped cervical incision with removal of the internal half of the clavicle was performed and the following steps were carried out: 1- Dissection free or resection of the subclavian vein when involved in the tumor (n = 7); 2- Section of the scalenus muscles in free margin, and resection of the cervical portion of the phrenic nerve when invaded (n = 6); 3- Exposure of the subclavian artery which was resected in 9 patients (prosthetic replacement n = 7, end to end anastomosis n = 2), and resection of the vertebral artery (n = 5); 4- Dissection free of the brachial plexus up to the spinal foramen, with Tl resection (n = 15); 5- Section of invaded upper ribs in free margins (n = 29); 6- En-bloc removal of chest wall and lung tumor was possible through this single approach in 9 patients (wedge resection n = 7, lobectomy n = 2) with extension of the cutaneous incision into the delto-pectoral groove.

An additional posterior thoracotomy was necessary in the remaining patients for a larger chest wall resection below the second rib. This additional step is less and less required while experience with cervical approach is increasing.

There were no operative deaths. Post operative radio-therapy was given to 25 patients, and chemo-therapy to 11 patients.

Median survival rate was 20,8 months, and cumulative survival rate was 77, 45 and 30% at 1, 2 and 5 years respectively. No significant difference was found among patients with vascular invasion (n = 12). Five with subclavian artery resection are still alive at 4, 18, 19, 28, and 71 months.

Conclusion: - Radical surgery of apical lung tumors invading structures above the thoracic inlet can provide an acceptable survival rate.

- Such a goal can only be achieved through an anterior transcervical approach.

2:30 p.m. BASIC SCIENCE LECTURE

Twinning

Kurt Benirschke, M.D., San Diego, California

3:15 p.m. INTERMISSION - VISIT EXHIBITS

*By Invitation

4:00 p.m. SCIENTIFIC SESSION - Los Angeles Ballroom

9. Prognosis of Patients With Hypertrophic Obstructive Cardiomyopathy After Transaortic Myectomy. Late Results up to 25 Years.

HAGEN D. SCHULTE, M.D.*, WOLFGANG H. BIRCKS, M.D.

and BENNO LOESSE, M.D.*

Duesseldorf, Germany

Long-term results after surgery for HOCM are less well documented than data concerning the early outcome.

Out of a total series of 353 patients (pts.) (210 males, 143 females, mean age 41.7 years) operated upon since 1963 up to June 1991,262 pts. had trans-aortic myectomy only (mortality rate 3.1%, n = 8), whereas 91 pts. needed additional cardiac procedures (mortality 8.8%, n = 8). Since 1984 the early mortality rate could be reduced to 1.5% (2 of 137 pts.) and 1.8% (1 of 56 pts.), respectively. There were no differences for typical (subvalvular) and for atypical (midventricular) HOCM.

A complete follow-up study could be performed for 309 pts. who survived surgery in the years 1963 to 1989. The longest follow-up time was 25.2 years, the shortest 1 year (mean 6.6 years). During the observation period 36 pts. (11.6%) died. The death of 17 pts. was closely related to HOCM (sudden death n = 8, LV-failure n = 4, embolic events due to atrial fibrillation n = 4, reoperation for residual symptomatic HOCM n = 1). Other causes - non related to HOCM - were responsible for the death of 19 pts. (extracardiac disease n = 15, coronary artery disease n =4, double valve replacement after acute native valve endocarditis n= 1). In consideration of these data there was a total yearly death rate of 2.2%, in close relation to HOCM it was 1.1%.

Most of the survivors (n = 257) belong to clinical class I and II (NYHA) at the end of the observation period (80.9%, n =208). Reoperations because of primarily insufficient myectomy had to be performed in 3 pts. with 1 death. Additional valve replacement was necessary in 4 pts. with 1 death, and 2 pts. had coronary revascularisation.

In conclusion, our long-term follow-up data indicate a reduced late mortality rate after surgery compared to pts. after medical treatment. In symptomatic pts. and failing medical therapy the prognostic benefit of surgery appears to become more and more evident.

*By Invitation

10. Transhiatal Esophagectomy for Benign and Malignant Disease of the Intrathoracic Esophagus

MARK B. ORRINGER, M.D. and

MACK C. STIRLING, M.D. *

Ann Arbor, Michigan

Since 1977, of 614 patients undergoing a transhiatal esophagectomy (THE), the operation has been performed in 559 with diseases of the in-trathoracic esophagus: 164 (29%) benign and 395 (71%) malignant (6% upper, 30% middle, and 64% lower). The benign esophageal diseases included strictures of varying etiology (41%); neuromotor dysfunction-achalasia (31%), esophageal spasm (7%); acute perforation (10%); acute caustic injury (9%); and others (2%). Among the patients with benign disease, 56% had undergone at least one prior esophageal operation and 29% had a history of between two and six esophageal operations. THE was possible in 99% of patients in whom it was attempted. Esophageal resection and reconstruction were performed in a single operation in all but 10 patients. The esophageal substitute was positioned in the posterior mediastinum in the orginal esophageal bed in 96%. Stomach was used to replace the esophagus in 544 patients (97%) and colon in 15 (3%) who had undergone prior gastric resections.

Hospital mortality was 2% in patients with benign disease and 5% in patients with carcinoma. There was 1 intraoperative death. Complications included intraoperative entry into a pleural cavity requiring a chest tube (73%), anastomotic leak (8%), recurrent laryngeal nerve injury (6%), and chylothorax (< 1%). Three patients required re-operation for mediastinal bleeding. Average intraoperative blood loss was 928 ml (1136 ml for benign disease and 833 ml for carcinoma). 513 patients (91%) were discharged able to swallow within three weeks of operation. The actuarial survival of the patients with carcinoma is similar to that reported after more traditional transthoracic esophagectomy. Among patients with benign disease, excellent functional results have been achieved in more than 84% after a cervical esophagogastric anastomosis. While approximately 50% have required one or more anastomotic dilations within 1-3 months of operation, true anastomotic strictures have developed in <7%. Clinically significant gastroesophageal reflux has occurred postoperatively in <1%. THE is feasible in most patients requiring esophageal resection for either benign or malignant disease and is a safe, well-tolerated operation if performed with care and for the proper indications.

*By Invitation

11. Long-Term Function of Cryopreserved Aortic-Valve Homografts: A 10 Year Study

JAMES K. KIRKLIN, M.D., DAVID C. NAFTEL, Ph.D.*,

WILLIAM NOVICK, M.D.*, DENNIS C. SMITH, M.D.*,

ALBERTO. PACIFICO, M.D., JOHN W. KIRKLIN, M.D.,

ROBERT C. SOURCE, M.D.*, SANDRA J. PHILLIPS, B.S.*,

and NAVIN C. NANDA, M.D. *

Birmingham, Alabama

Cryopreserved aortic valve (AV) homografts have become an accepted AV substitute, but long-term studies with echocardiographic (echo) assessment of valve function are largely unavailable. Therefore, the following study of our 10-year experience with AV homografts was undertaken. Between 1981 (the introduction of Cryopreserved homografts at our institution) and 4/1/90, 163 Cryopreserved AV homografts were implanted in 163 patients (pts) (ages 9 mo to 80 yrs, median 46 yrs) of which 148 were implanted in the infra-coronary position and 15 as aortic root replacements. Serial 2-Dimensional (2-D) echo studies (n = 322) were obtained in 136 pts 1 day to 108 months after operation, with 35 pts receiving 2-D echo studies more than 5 yrs post-op.

Overall survival was 93% at 1 yr and 90% at 5 yrs. Survival of pts undergoing isolated infra-coronary free-hand homograft AV replacement was 95% at 1 yr, 93% at 5 yrs, and 92% at 8 yrs. Eleven homograft valves were ex-planted, 2 at the original operation due to obstruction, 6 at 0.5 to 41 mos due to aortic regurgitation (AR) (n = 4) or left ventricular outflow obstruction (n = 2), and 3 at 6, 35, and 92 mos for probable degeneration with progressive incompetence (n = 2) or calcific stenosis (n = 1). Freedom from explantation for any reason was 83% at 8 yrs. Surviving patients had a mean NYHA Class of 1.2 at 5 yrs and 1.4 at 8 yrs post-implantation. Mean echo AR (grade 0, no AR to grade 4, severe AR) was 0.5 at 1 mo, 1.0 at 1 yr, 1.3 at 5 yrs and 1.4 at 8 yrs post-implantation. "Probable valve degeneration," as evidenced by valve degeneration at explant, severe AR (4/4) by post-op echo without reoperation, and/or death related to valve failure was identified in 5 pts at 6, 35, 36, 60, and 92 mos after implantation. The overall freedom from probable valve degeneration was 97% at 5 yrs and 85% at 8 yrs. By multivariable analysis, no specific risk factors for degeneration were identified.

Inferences:

* Early and late survival is excellent following homograft AVR with an 8 yr survival of 92% after isolated homograft AVR.

* The quality of life is excellent with little progression of AR in most pts for at least 9 yrs.

* Valve degeneration is unusual during the first 8-10 yrs, but may rarely occur after about the first 6 mos. Eighty-five % of patients are expected to be free of valve degeneration at 8 yrs.

*By Invitation

12. Experience in 112 Pulmonary Thromboendarterectomy Operations Over a Two Year Period

STUART W. JAMIESON, M.D., WILLIAM R. AUGER, M.D.*,

PETER F. FEDULLO, M.D. *,

RICHARD N. CHANNICK, M.D. * and

KENNETH M. MOSER, M.D.*

San Diego, California

Three hundred pulmonary thromboendarterectomy operations have been performed at this institution since 1970. Of these, 112 were done by one surgeon over the last 24 months. The operation involves a median ster-notomy incision, the institution of cardiopulmonary bypass, and cooling with circulatory arrest. Incisions are made in both pulmonary arteries into the lower lobe branches. Pulmonary thromboendarterectomy is always bilateral, with removal of both thrombus and an endarterectomy plane from all involved lobes. The right atrium is routinely explored for atrial septal defects. Changes in the technique have been made to allow more thorough revascularization, and shorter circulatory arrest times. This has produced improved results.

Comparison of the last 100 cases (February 1990 to October 1991) to 100 cases done prior to the institution of new methods showed a mean total circulatory arrest time of 34.35 ± 14 vs 58.14 ± 23.5 (p < 0.0001). The incidence of transient post-operative delirium decreased to 10% from 26%, post-operative arrhythmias 15% from 26% and mortality 9% from 16%. The majority of cases have exhibited normal post-operative hemodynamics, and late functional results have been excellent.

Chronic pulmonary thromboembolism that is surgically correctable is. likely an under-diagnosed entity. Pulmonary thromboendarterectomy can be performed with an acceptable risk and good symptomatic results.

*By Invitation