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Back to Annual Meeting Program
1:45 p.m. SIMULTANEOUS SCIENTIFIC SESSION A - ADULT CARDIAC SURGERY South Sheraton Ballroom
Moderators: Karl H. Krieger, M.D. Marko I. Turina, M.D.
19. IMPROVED EVENT FREE SURVIVAL FOLLOWING TRANSMYOCARDIAL LASER REVASCULARIZATION VERSUS MEDICAL MANAGEMENT IN PATIENTS WITH UNRECONSTRUCTED CORONARY ARTERY DISEASE. Robert J. March, M.D.*, Sara Aranki, M.D.*, Steven Boyce, M.D.*, Lawrence H. Cohn, M.D., Denton A. Cooley, M.D., John R. Crew, M.D., Gregory Fontana, M.D.*, O. Howard Frazier, M.D., Hartley P. Griffith, M.D, Kevin P. Landolfo, M.D.*, Allan Lansing, M.D, James Lowe, M.D, Bruce W. Lytle, M.D, Mahmood Mirhoseini, M.D. and Craig Smith, M.D. Chicago, Illinois; Boston, Massachusetts; Washington, DC, Houston, Texas; San Francisco and Los Angeles, California; Pittsburgh, Pennsylvania; Durham, North Carolina; Louisville, Kentucky and Cleveland, Ohio Discussant: Ralph J. Damiano, Jr., M.D.
To evaluate the efficacy of Transmyocardial Laser Revascularization (TMR) in the treatment of symptomatic, end-stage coronary artery disease (CAD), 160 patients from 12 U.S. centers were enrolled in a 1:1 randomized, prospective study comparing TMR to continued Medical Management (MM). Of the 77 patients initially randomized to TMR using a CO2 Laser (PLC Medical Systems, Inc.), 72% improved by at least 2 anginal classes. In the 83 patients randomized to the MM group, the angina class remained unchanged in 69% and worsened in 31%. Event free survival for death, unstable or Class IV angina at six months, was 73% for the TMR group versus 12% for the MM patients (p=0.0001). Quality of life indices increased an average of 127% for patients undergoing TMR compared to no change in the MM group. Twenty-six patients (31 %) crossed over from MM to TMR due to worsening angina or the development of unstable symptoms. There was a 27% perioperative mortality for this crossover group compared to a 1% perioperative mortality for patients having TMR initially. The study mortality was 16% for patients randomized to MM and 6% for those randomized to TMR. Event free survival, angina class and quality of life appear improved by TMR compared to MM in patients with symptomatic, end-stage CAD. Continued MM associated with a worsening clinical status significantly increases the risk of TMR, thereby supporting the early application of this treatment modality.
*By invitation §20. TRANSMYOCARDIAL LASER TREATMENT DENERVATES CANINE MYOCARDIUM. King F. Kwong, M.D.*, Georgios K. Kanellopoulos, M.D.*, Joshua C. Nickols*, Stephen Pogwizd, M.D.*, Jeffrey E. Saffitz, M.D., Ph.D.*, Richard B. Schuessler, Ph.D.* and Thoralf M. Sundt, III, M.D.* St. Louis, Missouri Sponsored by: William A. Gay, Jr., M.D., St. Louis, Missouri Discussant: Gerald D. Buckberg, M.D.
Transmyocardial laser treatment (TML) reduces angina clinically. The objective of our study was to test the hypothesis that TML alters the cardiac nerve fibers which convey the pain of angina pectoris. Methods: Left thoracotomy was performed in sixteen adult mongrel dogs that were divided into three treatment groups: laser (n = 5), phenol (n = 5), and sham (n = 6). A portion of the anterior left ventricule (LV) was subjected to the creation of transmyocardial channels with a Holmium:YAG laser, phenol application on the epicardium (which chemically destroys cardiac afferent nerve fibers), or no treatment. Cardiac afferent nerves were stimulated with topical epicardial bradykinin (300 ug/150 ul), a potent algesic, before any treatment and again at two weeks after operation; the resulting central nervous system mediated reflex decrease in systemic mean arterial blood pressure (MAP) was measured. Immunoblot analysis was performed on treated and untreated LV myocardium of each dog using antibody for tyrosine hydroxylase, a neural-specific enzyme. Results: Reflex systemic arterial pressure changes were seen with all dogs upon bradykinin stimulation prior to treatment. At two weeks post-operatively, LV areas treated with laser or topical phenol failed to show any response to bradykinin but untreated LV regions in the same dogs remained responsive. All sham dogs were responsive to repeat bradykinin stimulation (see table). Immunoblots demonstrated loss of tyrosine hydroxylase immunoreactivity only in the treated regions of phenol and laser dogs.
Conclusion: Transmyocardial laser treatment destroys cardiac nerve fibers, which may contribute to the reduction of angina pectoris seen clinically.
1994-96 Robert E. Gross AATS Scholar §Author has a relationship with CardioGenesis Corp. *By invitation 21. SEVEN-YEAR FOLLOW-UP OF CORONARY ARTERY BYPASSES PERFORMED WITH AND WITHOUT CARDIOPULMONARY BYPASS. Steven R. Gundry, M.D., Matthew Romano*, Howard Shattuck*, Anees J. Razzouk, M.D.* and Leonard L. Bailey, M.D. Loma Linda, California Discussant: Federico J. Benetti, M.D.
There has been resurgent interest in coronary revascularization performed on the beating heart (BHCABG). The advantages of shortened hospital stay, reduced costs, lessened patient discomfort and elimination of the negative effects of cardiopulmonary bypass must be weighed against the untoward effects of constructing bypasses on a moving field and the potential of limiting full revascularization. Heretofore, there has been no long term followup or any comparison of this technique to traditional coronary artery bypass with cardioplegia (CABG). From June 1989 to July 1990, all patients presenting for coronary revascularization to three surgeons were considered for BHCABG: 107 underwent successful BHCABG while 112 were felt unsuitable and underwent revascularization on bypass with cardioplegia (CABG). Mean ages (65 ± 10 yrs) and risk factors were identical. BHCABG pts had 2.4 ± 0.9 grafts versus 3.3 ± 1.1 for CABG pts. At 7 year followup, the following results were obtained:
No CABG pt required reoperation while the majority of reinterventions on the BHCABG group were PTCA's (15/21 (71%)).
In conclusion, despite one less graft/pi, at 7 year followup, survival and cardiac death rates were identical between pts whose grafts were performed off bypass and those on bypass. In contrast, twice as many BHCABG pts required recath (30% vs 16%) and 20% of BHCABG pts needed a second intervention vs only 4% of on bypass pts. These results demonstrate that limited revascularization of the beating heart provides excellent long term results compared to full revascularization on bypass but will require approximately a five fold increase in re-interventions to achieve these results.
*By invitation
2:45 p.m. INTERMISSION - VISIT EXHIBITS 3:15 p.m. SIMULTANEOUS SCIENTIFIC SESSION A - ADULT CARDIAC SURGERYSouth Sheraton Ballroom
Moderators: Karl H. Krieger, M.D. Marko I. Turina, M.D.
22. FIVE-YEAR RESULTS OF CORONARY BYPASS GRAFTING USING THE RADIAL ARTERY. Christophe Acar, M.D.*, Ahmad Ramshey, M.D.*, Jean Yves Pagny, M.D.*, Bernard Beyssen, M.D.*, Jean Noel Fabiani, M.D.*, Alain Deloche, M.D.* and Alain F. Carpentier, M.D., Ph.D. Paris, France Discussant: Hendrick B. Earner, M.D.
Since its revival in 1989, the radial artery (RA) was used as a conduit in 783 patients undergoing coronary artery bypass. The aim of this study was to assess the long term clinical results as well as the late patency rate of the RA grafts.
A complete follow-up was obtained for the first one hundred consecutive patients surviving the operation. Patients were reviewed after a mean follow-up of 5.4 years (4 to 7 years postoperatively). Age ranged from 38 to 84 years (mean: 68 ± 8 yrs). The mean number of grafts was 2.6 ± 0.8 including RA (n = 128). left internal mammary artery (IMA) (n = 94), right IMA (n=18), free IMA (n=11) and vein (n=12). RA grafts were anastomosed to the circumflex (51%), right coronary (29%), diagonal (16%) and left anterior descending coronary artery (LAD) (4%) and the left IMA grafts were anastomosed to the LAD (94%) or circumflex coronary artery (6%).
Eleven patients died during the period of follow-up (cardiac related death: 3, non-cardiac: 8). The other 89 patients were asymptomatic (81%) or had occasional angina (8%). Two patients had congestive heart failure (CHF) (NYHAIII/IV). Pharmacological treatment of patients was as follows: calcium channel blockers (53%), beta blockers (34%), nitrates (46%), aspirin (70%), coumadin (14%). Three patients underwent percutaneous transluminal angioplasty during the period of follow-up and there was one reoperation for aortic valve stenosis. There was no other morbidity at the site of RA removal than a mild dysesthesia of the thumb in 12 cases.
An EKG stess test was obtained in all but four cases (patients > 80 years of age, CHF) (n = 85). Tests were performed for 78 ± 5% of the predicted maximal heart rate. Stress test was negative in 71 cases and positive in 14 cases (EKG changes alone (12) or with chest pain (2)). A routine control angiogram was perfomed in 50 cases (including all symptomatic patients) at a mean follow-up of 5.6 years. The patency rate of the RA grafts was 84.2% (excellent result: 47/57, stenosis 1/57, string or occlusion: 9/57).
Haemodynamic factors that could compromise graft function were noted in 5/9 occluded RA grafts: no stenosis on the native coronary vessel (n = 4), progression of atheroma on the distal run-off (n = 1). The patency rate of the left IMA grafts was 89.8% (excellent result: 42/49, stenosis: .2/49, string or occlusion: 5/49).
Conclusion: the use of the RA for coronary bypass grafting provides excellent clinical and angiographic results at 5 years.
*By invitation 23. DOUBLE VALVE REPLACEMENT WITH RECONSTRUCTION OF THE FIBROUS BODY BETWEEN THE AORTIC AND MITRAL ANNULI. James Kuo, M.D.*, Tirone E. David, M.D., Susan Armstrong, M.Sc.* and Joan Ivanov, M.Sc.* Toronto, Ontario, Canada Discussant: Alain F. Carpentier, M.D.
The fibrous body between the aortic and mitral annuli may be destroyed by infection, calcification or multiple previous mitral valve replacement, making double valve replacement difficult. A solution for this problem is to excise the aortic and mitral valve and the diseased fibrous body between them by extending the aortotomy into the dome of the left atrium and then into the mitral valve. Once this is done the base of the left ventricle is widely exposed and the mitral and aortic orifices become a single orifice. If only the fibrous tissue between the mitral and aortic annuli was excised, reconstruction is accomplished by a triangular shaped patch of glutaraldehyde bovine pericardium sutured to the lateral and medial fibrous trigones and to the aortic root. If the entire mitral annulus was debrided because of infection or extensive calcification, a large oval shaped patch of bovine pericardium is sutured to the endocardium of the left ventricle posteriorly and to the base of the aortic root superiorly; an opening is made in this patch to create a mitral annulus and secure a mitral valve prosthesis. With either procedure, the roof of the left atrium is closed with a separate triangular shaped patch before an aortic valve prosthesis is implanted. This operation is also useful to enlarge both the mitral and aortic annuli.
This operation was performed in 43 pts because of multiple previous valve replacement (17 pts), infective endocarditis of the aortic and mitral valve with abscess (15 pts), extensive calcification of the base of the heart (6 pts), and enlargement of the aortic and mitral annuli (5 pts). There were 20 men and 23 women with a mean age of 59 years, range 33 to 81. Thirty-one pts had had at least one previous valve replacement. All pts were in NYHA functional classes III and IV, and 9 pts were moribund at the time of surgery. There were 7 operative deaths (16%). Two pts required reoperation, one for acute prosthetic valve endocarditis and one for paravalvular leak. Pts have been followed for a mean of 38 ± 30 months. There have been 6 late deaths. The actuarial survival at 5 years was 56% ± 6%. There has been no late patch or prosthetic valve dehiscence.
This operation has provided satisfactory results in pts with extremely complex aortic and mitral valve pathology.
*By invitation 24. CLINICAL AND HEMODYNAMIC RESULTS OF 174 AORTIC VALVE REPLACEMENTS WITH A STENTLESS PORCINE VALVE. Francis D. Ferdinand, M.D.*, John R. Pepper, F.R.C.S.*, Asghar Khaghani, F.R.C.S.*, Sue Edwards, R.G.N.* and Magdi H. Yacoub, F.R.C.S., Ph.D. London and Harefield, England Discussant: Edward D. Verrier, M.D.
A stentless valve has the potential advantages of better post-operative haemodynamics, long-term function and overall quality of life. Newer xenograft devices may mimic homografts in this respect; and in addition, offer the advantage of uniform availability. We report our results in 174 patients from July 1992 to July 1996 with the Toronto SPV valve. The mean follow-up was 16 months (range 0-38 months) and the percent follow-up was 97%. The average age was 68.1 years (range 35 to 89) and 66% were male. Pre-operatively, 2% were in NYHA Functional Class I, 43% in Class II, 50% in Class III and 5% in Class IV. Valve sizes implanted ranged from 20 to 29 mm. Forty-four point nine percent of patients had concomitant procedures of which 42% were CABG. Mean cardiopulmonary bypass time (mean ± SD) was 119.6 ± 35.8 minutes and cross clamp time was 91.4 ± 24.3 minutes. Post-operatively, at mean follow-up of 16 months, 79% of patients were in NYHA Functional Class I, 20% in Class II, 1% in Class III and 0% in Class IV. Echocardiographic analysis at follow-up revealed a mean systolic gradient ranging from 4.2 to 9.5 mmHg with no significant differences between valve sizes implanted. There was none or trivial aortic insufficiency in 85% of patients, 5% had mild, and 4% had moderate. There was no progression of aortic insufficiency during follow-up. There was a 5.7% early (≤ 30 d) mortality: one was valve-related and 9 were non valve-related deaths. There were four late deaths, one of which was valve-related. There were one early and 2 late cases of prosthetic valve endocarditis. At 2 years, freedom from death (%, 95% CL) was 90.9, 86.3-95.5; freedom from endocarditis was 97.3, 94.2-100; and freedom from thromboembolism was 95.2, 91.1-99.2.
It is concluded that the Toronto SPV stentless valve offers predictable performance and is associated with good early and intermediate results. Further experience is required to define the long-term performance particularly with regards to thromboembolism and endocarditis.
*By invitation 25. OVER 60 MINUTES OF DEEP HYPOTHERMIC CIRCULATORY ARREST WITH RETROGRADE CEREBRAL PERFUSION IS NOT A RISK FACTOR FOR MORTALITY AND STROKE IN AORTIC ARCH SURGERY. Yutaka Okita, M.D.*, Shinichi Takamoto, M.D.*, Motomi Ando, M.D.*, Tetsuro Morota, M.D.*, Ritsu Matsukawa, M.D.* and Yasunaru Kawashima, M.D. Osaka, Japan Discussant: M. Arisan Ergin, M.D.
[Purpose] To investigate perioperative variables that affect mortality and cerebral outcomes in patients with aneurysm of the aortic arch.
[Patients] From May 1993 until September 1996, 148 patients with aneurysm of the aortic arch underwent surgery using DHCA combined with RGCP technique. Age at operation was 63.9 ± 11.6 years and 52 patients were over 70 years old. Of 70 patients with aortic dissection, 28 had acute dissection. Twelve patients had ruptured aneurysms. Fourteen patients had previous surgery on the thoracic aorta. Etiologies of the aneurysm were atherosclerosis in 123 patients and others in 25. Preoperative complications consisted with AAA in 24 patients, coronary arterial disease in 19, cerebrovascular lesions in 17, valvular heart disease in 15, COLD in 9, renal failure (RF) in 5, and peripheral vascular obstruction in 5.
[Methods] Median sternotomy was used in 92 patients and left thoracotomy in 56. Twenty-eight patients underwent replacement of the ascending aorta, including proximal arch, 70 had total arch replacement, 38 had replacement of the distal arch, and 12 had simultaneous replacement of the distal arch and the descending aorta or thoracoabdominal aorta. Arterial cannula was inserted in the ascending aorta in 50 patients and in the femoral artery or descending aorta in 78. Concomitant surgery was performed in 22 patients. [Results] There were 15 (10.1%) early deaths. Postoperative stroke was found in 6 (4.0%) patients and transient delirium in 34 (22.9%). Duration of the bypass, cardiac arrest and DHCA+RGCP was 187 ± 78 minutes, 79 ± 38 minutes and 49 ± 17 minutes respectively. Duration of the bypass was over 180 minutes in 16 patients, cardiac arrest over 120 minutes in 24, and DHCA+RGCP over 60 minutes in 35 (95 minutes at maximum). Postoperative wake-up was noticed at 7.5 ± 8.2 hours and extubation was obtained at 47.1 ± 107.8 hours after operation. Major complications consisted with respiratory problems in 22 patients, bleeding in 18, low cardiac output in 10, RF in 8, septicemia in 3, and DIG in 2. Stepwise logistic regression analysis of 31 perioperative variables demonstrated that the significant risk factors for mortality were ruptured aneurysm, preoperative COLD, and perioperative stroke. Risk factors for stroke were ruptured aneurysm and replacement of the distal arch. Risk factors for delirium were age over 70 years and atherosclerotic etiology. Risk factors for delayed awakening (over 24 hours)was ruptured aneurysm and for delayed extubation (over 36 hours) were emergency surgery and postoperative respiratory complications. Duration of DHCA+RGCP did not correlate to postoperative wake-up time (r=0.03, p=0.80), extubation time (r=0.12, p=0.92), and hospital stay (r=0.05, p=0.69). The difference for the incidence of mortality (p=0.91), stroke (p=0.86), and delirium (p=0.47) were not significant between two groups of patients, one with over 60 minutes of DHCA+RGCP and other.
[Conclusion] Over 60 minutes duration of DHCA+RGCP was not a risk factor for early mortality, stroke, and delirium in patients who underwent surgery for aneurysms of the aortic arch.
4:35 p.m. EXECUTIVE SESSION (Limited to Members)
6:30 p.m. MEMBER RECEPTION
*By invitation 1:45 p.m. SIMULTANEOUS SCIENTIFIC SESSION B - GENERAL THORACIC SURGERY North Sheraton Ballroom
Moderators: Victor F. Trastek, M.D. Douglas J. Mathisen, M.D.
26. EXPERIENCE WITH LIVING LOBAR TRANSPLANTATION FOR NON - CYSTIC FIBROSIS INDICATIONS. Vaughn A. Starnes, M.D., Mark L. Barr, M.D.*, Felicia A. Schenkel, R.N.*, Monica V. Horn, R.N.*, Robbin G. Cohen, M.D.*, Jeffrey A. Hagen, M.D.* and Winfield J. Wells, M.D.* Los Angeles, California Discussant: G. Alec Patterson, M.D.
Since developing a living donor bilateral lobar transplantation protocol for cystic fibrosis patients (n = 37, 1 year survival of 73%), our indications have expanded to include recipients with other diagnoses. We report on our experience in 6 non-cystic fibrosis patients with primary pulmonary hypertension (PPH, n = 3), viral obliterative bronchiolitis (VOB, n=1), post-chemotherapy pulmonary fibrosis (PF, n=1), and bronchopulmonary dysplasia (BPD, n = 1). The average age of the 6 patients was 16.6 (range 9 - 32), all were female, 2 were on preoperative steroids, 2 were in-hospital, and the mean preoperative PCO2 was 62 mmHg (range 36 - 120). The 1 patient with PF was intubated on high frequency jet ventilation. Each recipient received a right lower lobe (n = 5) or a right middle lobe (n = 1), and a left lower lobe (n = 6) from a total of 12 donors representing various combinations of the recipients' family, (mothers n = 5, fathers n = 4, brother n = 1, sister n = 1, cousin n = 1). The average recipient height was 59.5 inches (range 53 - 63) and the mean weight was 87.6 pounds (range 66 - 142). The mean donor height was 66 inches (range 59 - 73) and the weight was 160 pounds (range 100 - 213). Average number of HLA matches was 3.0 (range 1 - 6) and mismatches was 2.4 range (0 - 4). With an average follow up of 1 year the overall survival is 83%. The 1 death occurred in the VOB patient with recurrence of viral pneumonia at one month. Of the remaining five patients there have been no rejections and no other infections. For the 4 patients followed at least 6 months, mean FVC was 69% predicted (range 52 - 87), FEV, 69% predicted (range 54 - 83), FEF 25/75 73% predicted (range 47 - 97), DLCO/VA 76% predicted (range 66 - 85). For those patients with PPH, preoperative hemodynamics revealed mean pressures (in mmHg): RA 8 (range 2-13), PA 69 (range 60-77), PCWP 8 (range 7-10), C.I. 4.5 L/min/m2 (range 3.3-4.0) and PVRI 16.8 Wood units indexed to BSA (range 16.2 - 17.4). Postoperative hemodynamics revealed a mean RA 2 (range 0 - 4), PA 18 (range 17 - 20), PCWP 6 (range 5 - 7), C.I. 5 (range 4 - 6) and PVRI 2.6 (range 2.2 - 3). Early results of living bilateral lobar transplantation for diseases other than cystic fibrosis have resulted in satisfactory survival and pulmonary function. Additionally, patients with severe PPH have had dramatic normalization of their hemodynamics despite the limited amount of lung tissue transplanted. The one year survival, incidence of rejections and infections appear to be superior to the results of CF patients in this small cohort experience.
*By invitation 27. POSTOPERATIVE CHEST X-RAYS: OPTIMUM USE IN THORACIC SURGERY. Thomas W. Rice, M.D, Ruffin J. Graham, M.D.*, Nancy A. Obuchowski, Ph.D.*, Thirugnanam Agasthian, M.D.*, Neil A. Christie, M.D.*, Kathleen Gaebelein, M.S.N.* and Moulay A. Meziane, M.D.* Cleveland, Ohio Discussant: Claude Deschamps, M.D.
Daily portable chest x-rays are routinely ordered following thoracic surgery. To assess the efficacy and cost of this practice and to determine the optimum use of postoperative x-rays, a prospective review of all portable chest x-rays following 100 consecutive elective thoracotomies (DRG 75) was conducted. Each x-ray initiated a three-part survey. First, the surgeon listed whether or not the x-ray was routine and the anticipated management if the x-ray were not available. The radiologist then interpreted and scored the x-ray as either: A, expected findings requiring no intervention; B, minor findings requiring intervention; or C, major findings requiring intervention. Finally, the x-ray and the interpretation were returned to the surgeon. Any interventions necessitated by the x-ray were recorded.
In 6 months, 99 patients underwent 84 pulmonary resections and 16 other major procedures. Postoperatively, 769 portable chest x-rays were ordered, median 5 per patient (range 2-49). Of these, 731 (95%) were routine and 38 (5%), non-routine. Severity scores were:
X-ray findings altered mangement in 43 of 769 x-rays (5.6%), in 33 routine (4.5%), in 10 non-routine (26.3%), in 13 A (2.0%), in 22 B (37.3%), and in 8 C (17.4%).
These results demomstrate that routine daily portable chest x-rays minimally impact management. It is, in fact, non-routine x-rays that more often alter management. If routine portable chest x-rays that cost $114 each in our institution were limited to one immediately after operation, only 133 x-rays (100 routine and 33 non-routine) would have been needed in the care of these patients. Elimination of 636 (82.7%) x-rays reduces the cost of care by $725 per patient ($286, 000 annually).
We conclude that for major thoracic procedures, it is safe, efficacious, and cost effective to initiate a protocol of one immediate postoperative portable chest x-ray as the standard order and additional portable x-rays only when clinically indicated.
*By invitation 28. GENE THERAPY FOR MALIGNANT MESOTHELIOMA: PRECLINICAL TOXICITY STUDIES LEADING TO A HUMAN CLINICAL TRIAL. W. Roy Smythe, M.D.*, John H. Kucharczuk, M.D.*, Daniel H. Sterman, M.D.*, Ashraf E. Elshami, M.D.*, Leslie A. Litzky, M.D.*, Steven M. Albelda, M.D.* and Larry R. Kaiser, M.D. Philadelphia, Pennsylvania Discussant: David J. Sugarbaker, M.D.
We previously demonstrated and reported promising efficacy utilizing adenoviral vector transfer of the herpes simplex thymidine kinase gene (HSVtk) followed by ganciclovir (GCV) administration with eradication of malignant mesothelioma in animal models. We now report results of animal toxicity studies and preliminary data from a Phase I human clinical trial.
Eighty Fischer rats received either 1x1010 pfu of intrapleural H5.01ORSVTK (adenovirus carrying HSVtk) followed by 14 days of intraperitoneal (IP) GCV. Serial blood samples and necropsies were obtained. No hematologic abnormalities were noted. Mild pleuritis, epicarditis, and pneumonitis were found at necropsy. Additional animals received 1.4x106 to 1.4x1010 pfu of H5.01ORSVTK to evaluate "dose-effect." Pleural and epicardial changes were more pronounced in the higher dose groups. H5.110CBlacZ, a vector carrying a marker gene, resulted in less pronounced inflammation. HSVtk DNA was noted by PCR in spleen, liver, and kidney without pathologic change.
Three baboons were treated with 1x1012 pfu of intrapleural H5.01ORSVTK followed by IP (infusion pump) GCV. No hematologic or radiographic toxicity was noted. Only mild pleuritis was noted at necropsy.
Fourteen patients with MM have been treated with intrapleural H5.01ORSVTK at escalating doses up to 3.2x1011 pfu followed by systemic GCV. Minimal toxicity has included fever, anemia, transient liver function abnormality, and vesicular skin rash.
In summary, HSVtk/GCV gene therapy for MM produced minimal toxicity in animals when given in the same schema as proposed for a human trial. Early results from a clinical trial confirm the safety of the approach.
*By invitation
2:45 p.m. INTERMISSION - VISIT EXHIBITS 3:15 p.m. SIMULTANEOUS SCIENTIFIC SESSION B - GENERAL THORACIC SURGERY North Sheraton Ballroom
Moderators: Victor F. Trastek, M.D. Douglas J. Mathisen, M.D.
29. MINIMALLY INVASIVE SURGICAL STAGING IS SUPERIOR TO ENDOSCOPIC ULTRASOUND IN DETECTING LYMPH NODE METASTASES IN ESOPHAGEAL CANCER. James D. Luketich, M.D.*, Richard Kim, M.D.*, Philip R. Schauer, M.D.*, Rodney J. Landreneau, M.D., Edmund S. Kassis*, Kathleen Urso*, Peter F. Person, M.D.* and Robert J. Keenan, M.D.* Pittsburgh, Pennsylvania Discussant: Thomas W. Rice, M.D.
Purpose: Endoscopic ultrasound (EUS) is widely used to assess the loco-regional extent of esophageal cancer, but few studies exist to validate its accuracy in nodal staging. Our objective was to compare EUS to video-assisted thoracoscopy (VATS) and laparoscopy (LAP) in evaluating the locoregional extent of esophageal cancer.
Methods: Twenty-six patients with esophageal cancer were identified over a 15-month period as having resectable disease by conventional non-invasive staging. EUS was performed followed by LAP/VATS. Tumor penetration (T) and nodal status (N) were recorded by EUS, LAP/VATS allowed lymph node sampling and limited T evaluation to rule out T4 involvement.
Results: In 8 patients EUS evaluation was NO, but LAP/VATS provided histologic confirmation of Nl in 6 of these patients. In 5/26 (19%) an obstructing lesion prevented EUS, and 3 of these had Nl by LAP/VATS. In 13 patients N1 disease was suspected by EUS, and 12/13 (92%) patients were histologically confirmed as N1 by LAP/VATS. The sensitivity and specificity of EUS for nodal evaluation were 65% and 66% respectively. The sensitivity of EUS dropped further (44%) when small nodal metastases (< 1 cm) were present and confirmed by LAP/VATS. LAP/VATS concurred with EUS evaluation of T-status in all cases. EUS was negative for metastatic disease in all 26 patients, but in 4/26 (15%), LAP identified liver metastases. In 3 patients CT suggested metastatic disease but LAP/VATS biopsies were benign. No deaths occurred following surgical staging, and the average hospital stay was less than 72 hours.
Conclusions: The overall accuracy of EUS in the diagnosis of nodal metastases in esophageal cancer was only 65% when compared to LAP/VATS. EUS was 100% accurate in evaluating T-status. EUS was severely limited in identifying small (< 1 cm) metastatic periesophageal lymph nodes (44% sensitivity). LAP/VATS improved the accuracy of staging locoregional involvement in esophageal cancer, and can be performed in the setting of high-grade obstructing lesions. LAP/VATS has the advantage of evaluating the thoracic and abdominal cavities for possible metastases.
*By invitation 30. RESECTION FOR BARRETT'S MUCOSA WITH HIGH GRADE DYSPLASIA - IMPLICATIONS FOR PROPHYLACTIC PHOTODYNAMIC THERAPY. Mark K. Ferguson, M.D. and Keith S. Naunheim, M.D. Chicago, Illinois and St. Louis, Missouri Discussant: Nasser K. Altorki, M.D.
Background Photodynamic therapy has recently been introduced as a technique for eradicating Barrett's mucosa with high grade dysplasia (HGD). However, distinguishing among HGD, carcinoma-in-situ, and invasive cancer, even with esophageal ultrasonography, is difficult. We sought to determine the incidence of invasive cancer and surgical and long-term outcomes after resection for HGD.
Methods We performed a retrospective review of patients who underwent esophagectomy for Barrett's esophagus from 1985 to 1996. Operative outcome, pathologic findings, and long-term survival were recorded.
Results During the study period 94 patients with Barrett's esophagus underwent resection. Of these, 14 were operated on for a preoperative diagnosis of HGD. There were 12 men and 2 women with a mean age of 64 years (range 35 to 76). The 14 patients rarely reported important dysphagia, and the mean weight loss was less than 2 kg. No patient received preoperative radiotherapy or chemotherapy. The operation was performed using a transhiatal approach in 9, through a left thoracotomy with an intrathoracic anastomosis in 3, through a left thoracotomy with a cervical anastomosis in 1, and using a modified Ivor Lewis approach in 1. Reconstruction was accomplished with the stomach in 12 patients and with a colon interposition in 2. The mean blood loss was 730 ml, and patients were transfused an average of 1.4 units of blood in the perioperative period. There was no operative mortality. Four patients suffered anastomotic leaks, 3 had pulmonary complications, and 3 had cardiovascular complications. The median length of stay was 14 days. The final pathology demonstrated dysplasia in 4 patients, carcinoma-in-situ in 1, and invasive carcinoma in 9 patients (64%). All patients with invasive carcinoma had T1NOMO Stage I disease. Follow-up is complete in all patients through October, 1996, for a mean duration of 33 months (median 22 months). All patients are alive and none of the patients with invasive cancer has recurrent disease.
Conclusions A substantial percentage of patients with Barrett's mucosa containing foci of HGD have invasive carcinoma at the time of diagnosis. The use of prophylactic photodynamic therapy for these patients may expose them to the unnecessary risk of harboring an untreated cancer in tissue layers too deep to permit the photoactive compound to be activated by laser energy. Surgical management of HGD, which is accompanied by a low operative risk and achieves an excellent long-term outcome, should remain the standard therapy for Barrett's esophagus with high grade dysplasia.
1986-88 Edward D. Churchill AATS Research Scholar *By invitation 31. ESOPHAGECTOMY FOR FAILED ANTIREFLUX SURGERY. Jeffrey A. Hagen, M.D.*, Michael Gadenstatter, M.D.*, Manfred P. Ritter, M.D.*, Tom R. DeMeester, M.D., Jeffrey H. Peters, M.D.*, Rodney J. Mason, M.D.* and Peter F. Crookes, M.D.* Los Angeles, California Discussant: Mark B. Orringer, M.D.
Introduction: Although most patients with gastroesophageal reflux disease (GERD) respond well to antireflux surgery errors in technique or procedure selection may result in failure. Most of these can be salvaged by a remedial antireflux procedure but in some esophageal function has deteriorated to the level where esophagectomy is a reasonable option. The aim of this study was to evaluate the indications and clinical outcome of esophageal resection in this setting.
Methods: Seventeen patients (M:F ratio 9:8, median age 54 years, range 27-66) who had failed previous antireflux procedures and presented with poor esophageal function and/or undilatable strictures had esophageal replacement over a 16 year period. Reflux symptoms were present for a median of nine years (range 1-30) prior to resection. All but one patient had severe dysphagia. Eight patients (47%) had one, five (29%) two and four (24%) three or more previous antireflux operations. Colon was used for replacement in 15 patients, jejunum in two. In seven patients the esophagectomy included a partial or total gastrectomy. Symptomatic improvement, meal capacity and weight change were assessed in 16 of the 17 patients at a median of seven years following surgery.
Results: Endstage disease was reflected by global loss of motility in 13 and an undilatable stricture in four patients. The former was identified by the presence of BOTH 40% or more simultaneous wave forms and contraction amplitudes less than 25 mmHg in the distal two thirds of the esophagus. Complications occurred in four patients and there was no mortality. Two patients required remedial surgery for delayed gastric emptying or bile reflux. The median hospital stay was 15 days (range 12-24). All patients stated that their preoperative symptoms were cured (6/16) or improved (10/16). Thirteen patients (81%) were able to eat three meals a day and twelve (75%) enjoyed an unrestricted diet. Six patients gained or maintained weight (median gain 6 lb.) and ten lost weight (median loss 12 lb.). Two thirds of the patients were at or above their ideal body weight when asked. Fourteen patients (88%) were fully satisfied with the results of the operation, while two would not undergo the same procedure again if they had to make the decision. Conclusions: Patients with endstage disease who have had failed antireflux procedures can be salvaged by esophageal resection with a high expectation of success. Indications include global loss of motility with or without undilatable strictures. The operation can be performed safely, restores the ability to eat and maintains nutritional status.
*By invitation 32. MASSIVE HIATUS HERNIA: EVALUATION AND SURGICAL MANAGEMENT. Donna E. Maziak, M.D.C.M.*, Tom R.J. Todd, M.D. and F. Griffith Pearson, M.D. Toronto, Ontario, Canada Discussant: MarkS. Allen, M.D.
Between 1960-1996 ninety-four patients with massive, incarcerated hiatus hernia were seen at our institution. The mean age was 64 years (39-85 years) with a male:female ratio of 1:1.8. Organoaxial volvulus was present in 61%. Clinical presentation in these patients included: dysphagia in 48%; chronic iron deficiency anemia in 38%; aspiration in 29%; and post-prandial pain in 56%. Symptomatic reflux, either present or remote, was seen in 83%. All patients had endoscopy. The esophagogastric junction was at a level above the diaphragmatic hiatus, denoting a sliding type of hiatus hernia, in all but 3 patients. Gross, endoscopic peptic esophagitis was observed in 36% of patients: ulcerative esophagitis in 22% and peptic esophagitis with stricture in 14%. Preoperative esophageal motility was done in all 42 patients since 1980. It was possible to advance the catheter beyond the esophagus into the stomach in 32 patients. Of these 32 complete manometric studies, the lower sphincter was hypotensive in 18 patients, and the amplitude of peristalsis in the distal esophagus was diminished in 20 patients. These are both features of significant gastroesophageal reflux disease (GERD). In 13 recent patients the distance between the upper and lower esophageal sphincters was measured during manometry. The average distance was 15.4 cm (11-20 cm), which is consistent with acquired short esophagus. The normal distance is > 18 cm. All 94 patients were treated surgically: 96% had a transthoracic repair with fundoplication, and a gastroplasty was added in 79% because of clearly defined or presumed short esophagus. There were 2 operative deaths. The mean follow-up was 70 months. Of the 88 patients followed-up, 80% are asymptomatic (excellent result); 15% have inconsequential symptoms requiring no therapy (good result); and 5 patients (4%) are improved but with significant symptoms (fair result). Two patients, neither of whom had the addition of gastroplasty, had poor results due to recurrent hernia and severe reflux. Both were successfully managed by reoperation and the addition of gastroplasty.
In summary, the majority of these 94 patients had symptoms, along with endoscopic, manometric and operative findings consistent with a sliding hernia, and a high incidence of reflux esophagitis and acquired short esophagus. True paraesophageal hernias appear rare when accurate endoscopy and motility are used. These observations support our choice of a transthoracic approach for repairs in most patients.
4:35 p.m. EXECUTIVE SESSION (Limited to Members)
6:30 p.m. MEMBER RECEPTION
*By invitation 1:45 p.m. SIMULTANEOUS SCIENTIFIC SESSION C -CONGENITAL HEART DISEASE Washington Ballroom
Moderators: Thomas L. Spray, M.D. Richard A. Hopkins, M.D.
33. CONOTRUNCAL REPAIR FOR TETRALOGY OF FALLOT: MID-TERM RESULT. Hiromi Kurosawa, M.D.*, Kiyozo Morita, M.D.*, Masaaki Yamagishi, M.D.*, Anton E. Becker, M.D.* and Robert H. Anderson, M.D.* Tokyo, Japan, Amsterdam, The Netherlands and London, England Sponsored by: Edward L. Bove, M.D., Ann Arbor, Michigan Discussant: Gary Lofland, M.D.
Because of the left sided main conduction bundle, the membranous flap can be safely used for closure of the VSD in tetralogy of Fallot.
Conotruncal repair consists of 1) a closure of VSD using the membranous flap or a muscle bar and not using the tricuspid septal leaflet, and 2) a short outflow patch with a wide monocusp. Elimination of fixation of the tricuspid septal leaflet could avoid dysfunction of the tricuspid valve and right ventricle.
Two hundred twenty-eight consecutive patients of tetralogy of Fallot underwent Conotruncal repair. Forty-four percent of patients were under two years old and 11% were less than twelve months old. Eighty-five percent of patients had a membranous flap at the postero-inferior border of VSD, 13% had a muscle bar between VSD and the tricuspid valve and only 2% had neither membranous flap nor muscle bar. Twenty cases had pulmonary atresia. Xenopericardial monocusp was used in the first 100 and PTFE monocusp has been used in the recent 128 patients. There were no early deaths and only 2 late deaths occurred (Late mortality = 0.08%) over a mean follow up period of 6.8 years. One death was due to pneumonia after reoperation for residual partial anomalous pulmonary venous return (PAPVR) and the other from heart failure due to coronary injury during operation. No patient required reoperation except for two with residual PAPVR. All patients had sinus rhythm and 55% had right bundle branch block. No patient has congestive heart failure or significant residual VSD. Most patients had no or trivial heart murmur indicating absence of residual VSD or outflow obstruction. Good coaptation of PTFE monocusp was revealed by echocardiogram up to five years after surgery. A consecutive group of 20 patients under 2 years-old underwent catheterization after surgery and showed CVP less than 10 mmHg, 0.46 of right/left ventricular pressure, normal right and left ventricular end-diastolic volumes, and normal election fractions of both ventricles.
In conclusion, Conotruncal repair for tetralogy of Fallot provides good quality of life, no significant hemodynamic residue, sinus rhythm, and low CVP.
*By invitation 34. THE SURGICAL MANAGEMENT OF MULTIPLE VENTRICULAR SEPTAL DEFECTS. Lucian A. Durham, M.D., Ph.D.*, Tetsuya Kitagawa, M.D., Ph.D.*, Ralph S. Mosca, M.D.* and Edward L. Bove, M.D. Tokushima, Japan and Ann Arbor, Michigan Discussant: John W. Brown, M.D.
The management of patients with multiple VSD's remains controversial. Primary closure, interventional catheter techniques, and palliative surgery all may have a role and specific management guidelines remain undefined. We reviewed the records of all 33 patients with multiple VSD's undergoing repair between 1/88 and 10/96. Pulmonary artery hypertension was present in 21 patients (group 1), while the pulmonary vascular bed was protected in the remaining 12 patients (group 2). Among group 1 patients, the mean age at repair was 5.9 ± 0.9 months and all but one were less than 12 months. VSD location was perimembranous (11), posterior muscular (4), midmuscular (4), anterior muscular (5), apical (8), and subpulmonary (2). Among the 24 perimembranous and muscular VSD's, closure was accomplished from a right atriotomy alone in 22, while 2 underwent a right ventriculotomy. Apical VSD's were closed from a limited apical left ventriculotomy and subpulmonary VSD's from a pulmonary artery approach. Major associated anomalies included coarctation (n = 6) and straddling tricuspid valve (n = 1). Reoperation was performed in 4 (immediately following bypass in 2) for additional VSD not diagnosed preoperatively. There were no early or late deaths, no heart block, and no significant residual VSD's. All patients remain free of significant residual conditions at a mean of 23.4 ± 5.1 months. Among group 2 patients, the mean age at repair was 6.6 ± 3.2 years and only one was < 1 year. VSD location was perimembranous (6), posterior muscular (4), midmuscular (6), anterior muscular (2), apical (1), and subpulmonary (1). Major associated anomalies included tetralogy of Fallot (2), valvar and/or infundibular pulmonary stenosis (4), DORV with hypoplastic LV (1), and isolated LV hypoplasia (1). Unsuccessful percutaneous device closure was attempted in 2 patients. There was 1 early death (DORV and LV hypoplasia). One patient required reoperation for residual VSD and 2 underwent cardiac transplantation for LV hypoplasia or dysfunction. There were no late deaths. Six patients remain alive without significant residual or transplantation at a mean of 36.2 ± 8.0 months.
This experience indicates that primary repair for infants with multiple VSD's is associated with good late outcomes. The right atrial approach is satisfactory for all muscular defects. Limited apical left ventriculotomy for apical defects was not a risk factor. Pulmonary artery banding should be limited to patients with complex associated defects.
*By invitation 35. FATE OF RIGHT VENTRICLE TO PULMONARY ARTERY HOMOGRAFT CONDUITS: DETERMINANT FACTORS OF LATE OBSTRUCTIONS. Jaroslav F. Stark, M.D., Kate Bull, M.D.*, Mila Stajevic, M.D.*, Muthu Jothi, M.D.*, Martin J. Elliott, M.D.* and Marc R. de Leval, M.D. London, England Discussant: F. Mark Lupinetti, M.D.
Materials and Methods: The factors determining the longevity of homograft conduits (HC) remain unclear and controversial. We have reviewed records of 425 patients who survived 30 days after placement of the pulmonary (P) ventricle to pulmonary artery HC. There were 329 aortic (A), 91 pulmonary and 5 unknown HC. The date of conduit failure was defined by the date of conduit replacement (88), balloon intervention (11), or death of the patient with the conduit in place (24). The following variables were entered into a Cox proportional hazards model: aortic versus pulmonary HC, antibiotics versus cryopreservation, ABO and Rh compatibility, type of material used for HC extension, age at operation, conduit number (reoperations). Because the prevalence of reoperations as well as of homograft type and preservation methods varied across the series, "conduit number" (1-425) was included in the multivariate models.
Results: First conduits and those inserted earlier in the series appeared to last longer than second conduits or those inserted later in the series (p = 0.0002 and 0.0005 respectively). Actuarial survival of first conduits was 83% at 5 and 55% at 10 years. For second, third and fourth conduits, the corresponding figures were 67% at 5 and 30% at 10 years. Regarded univariately, PHC did not perform better than AHC, even when conduit number was taken into account. Longevity did not appear to be influenced by the underlying diagnosis, age at operation, preservation technique, material used for conduit extension, or ABO and Rh matching.
Conclusions: The homograft longevity was not influenced by the use of AHC or PHC, nor by the homograft preservation technique. The most striking finding was that the second and third conduits did not last as long as the first conduits. A possible explanation for this disturbing finding is that it is more difficult at reoperation to optimise the flow dynamics through these conduits.
2:45 p.m. INTERMISSION - VISIT EXHIBITS
1973-74 AATS Graham Fellow *By invitation 3:15 p.m. SIMULTANEOUS SCIENTIFIC SESSION C -CONGENITAL HEART DISEASE Washington Ballroom
Moderators: Thomas L. Spray, M.D. Richard A. Hopkins, M.D.
36. ATRIOVENTRICULAR VALVE FUNCTION AFTER SINGLE PATCH REPAIR OF ATRIO VENTRICULAR CANAL DEFECT IN INFANCY: HOW EARLY SHOULD WE REPAIR? V. Mohan Reddy, M.D.*, Doff B. McElhinney, M.S.*, Andrew J. Parry, M.D.*, Michael M. Brook, M.D.* and Frank L. Hanley, M.D. San Francisco, California Discussant: James A. Alexander, M.D.
Patients (pts) with complete atrioventricular canal defects (CAVCD) are generally managed with medical therapy in very early infancy, largely due to technical concerns about the fragility of the atrioventricular valve (AW) tissue. We have taken the approach of completely repairing these pts earlier in infancy rather than continuing with prolonged medical management. From 7/92 to 9/96, 68 infants (<1 yr) underwent primary repair of CAVCD. Median age was 3.9 months (mo). Forty percent of pts were <3 mo of age and 80% were <6 mo. Significant associated lesions included tetralogy of Fallot or valvar pulmonary stenosis (7) , double-orifice left AVV (5), single left papillary muscle (2), aortic coarctation (3), and left superior vena cava (12). Preoperative common AVV insufficiency was severe in 2 pts, moderate in 15, mild in 32, and none in 19. Primary complete repair was performed in all pts except for 3 who had undergone neonatal coarctation repair between 1 and 4 weeks earlier. A single patch technique with division of the bridging leaflets was employed in all pts. The left AVV cleft was closed completely (57) or partially (10) in all but 1 pt with single left papillary muscle. Annuloplasty procedures were performed on the left AVV in 14 pts and on the right AVV in 2 pts. In 10 pts Transesophageal echocardiography demonstrated inadequate valve repair requiring a return to bypass for revision. There was 1 early death (1.5%), in a pt with single papillary muscle who underwent surgery at 45 days of age. None required reoperation in the early postoperative period, and only 1 pt had greater than mild left AVV insufficiency at discharge (moderate). During a median follow-up of 20 mo (1-49 mo), 3 pts had undergone late reoperation: 1 for left AVV replacement due to severe stenosis (5 mo post-repair) and 2 for subaortic membrane resection 22 and 23 mo post-repair. Follow-up left AVV regurgitation was moderate in 1 pt, mild in 25 pts and none in the rest. Twelve pts had mild right AVV insufficiency. Age (as a continuous variable) at surgery had no relation to early or late AVV function. There was no difference in the incidence and severity of AW insufficiency between pts younger than vs older than 3 mo of age.
Conclusions. Despite concerns about AW tissue fragility in very young pts, with proper techniques excellent results can be achieved. From neonates to older infants, age of repair appears not to influence AW function. Early surgical repair rather than aggressive medical therapy is preferable to avoid prolonged morbidity associated with waiting.
*By invitation 37. DOES AORTIC-PULMONARY ANNULUS MISMATCH PREDICT AORTIC INSUFFICIENCY AFTER THE ROSS PROCEDURE IN CHILDREN? Frank L. Hanley, M.D., V. Mohan Reddy, M.D.*, Doff B. McElhinney, M.S.*, Colin K. Phoon, M.D.* and Michael M. Brook, M.D.* San Francisco, California Discussant: Jan M. Quaegebeur, M.D.
Valvar insufficiency after pulmonary autograft aortic valve replacement (PAVR) can be due to a number of factors, including geometric mismatch between the native aortic and pulmonary annuli, previous or concomitant left ventricular outflow tract (LVOT) procedures, implantation techniques, and morphology of the pulmonary valve (PV). To identify factors predictive of PAVR insufficiency, we retrospectively analyzed morphologic and operative data in 38 children patients (age 4 d to 18 yrs; median 7.7 yrs) who have undergone PAVR since July 1992. One or more operations on the LVOT had previously been performed in 23 pts, including surgical valvotomy (18), subaortic resection (3), AV replacement (1), and a Konno procedure (1). No abnormal PV morphology was observed. The diameter of the PV was greater than that of the AV in 24 cases, equal in 3 cases, and less in 11 cases. The median difference between the PV and AV (PV-AV) was +3mm and ranged from +10 to -12mm. Thirteen pts had additional LVOT procedures performed at the time of PAVR (Konno =11, myectomy = 5), and a sinus obliteration technique was performed in 11 pts. PV-AV in pts undergoing Konno procedure ranged from +3 to +10mm. In these pts, geometric mismatch was corrected by ventriculoplasty. In all other pts the mismatch was corrected by gradual adjustment along the entire circumference of the autograft implant rather than by tailoring procedures at the commissures. Follow-up echocardiography at a median of 22 mo (1 to 38 mo) revealed no or trace aortic insufficiency (AI) in 28 pts, mild AI in 8 pts, and moderate AI in 2 pts. Distal aortic obstruction was present in 2 pts, 1 of whom had resulting moderate AI and underwent reoperation for arch augmentation. One other pt underwent aortic valve replacement 2 yrs post-PAVR for AI. There was no correlation between follow-up AI (≥miled) and age, PV-AV mismatch, previous or concurrent LVOT procedures, or sinus obliteration. Subtle variation in techniques of PAVR are probably more important determinants of post-PAVR AI than the other factors analyzed.
*By invitation 38. NEONATAL THYMECTOMY: DOES IT EFFECT IMMUNE FUNCTION? Winfield J. Wells, M.D.*, Robertson Parkman, M.D.* and Vaughn A. Starnes, M.D. Los Angeles, California Discussant: Steven R. Gundry, M.D.
Background. Thymectomy is frequently performed to improve exposure for complex congenital heart repair in the neonate. The impact on immune function has not been extensively investigated.
Methods. Nineteen neonates (<30 days of age) who had thymectomy at their operation for congenital heart repair were prospectively entered into a study to determine their subsequent immune function. Tests of immune competence included: T lymphocyte count and immunophenotype analysis (CD2, CD3, CD4, and CDS); Lymphocyte blastogenesis to mitogen (PHA), and antigen (tetanus toxoid). Antibody liters to tetanus were also determined. Samples were obtained pre-operatively, following immunization (~3 months), and at 1 year. At follow-up patients were asked about infections.
Results. Immunophenotype: The percentage of lymphocytes expressing CD3 (all T-lymphocytes), CD4 (helper T-cells), and CDS (suppressor T-cells) are reported in Table 1. Measurements were made prior to thymectomy, at about 3 months (following immunizations), and at one year.
Although there was a significant decrease in the percentage of T lymphocytes, this decrease did not reach a level that has been associated with clinical immunodeficiency. The CD4:CD8 ratio was within normal limits.
Blastogenic Response to PHA: Blastogenesis to PHA was normal prior to thymectomy, and continued to be so at the two subsequent study times (85903.2 ± 47304.2, 103974.1 ± 64296.8, 122544.7 ± 57220.6 CPM; p = N.S.). Responses to Tetanus: Blastogenesis to tetanus toxoid following immunization was normal in all except 3 patients, and one of these three was the only patient to show a low antibody liter to tetanus toxoid with a level less than 0.1 IU/ml.
Clinical Course: No study patient required re-admission for infection over the one year of follow-up. There were a reasonably normal number of infections including bronchitis, otitis, sinusitis, and conjunctivitis which were treated with antibiotics (mean 3.5 ± 3.4 events/patient), but there was no correlation with lymphocyte number or immune function.
Conclusions. Neonatal thymectomy results in a modest decrease in T-lymphocyte level, but there is no compromise in important immune function.
*By invitation 39. PEDIATRIC HEART TRANSPLANTATION FOLLOWING THE FONT AN OR GLENN PROCEDURE. Jan M. Quaegebeur, M.D., Mark E. Galantowicz, M.D.*, Robert E. Michler, M.D., Craig R. Smith, M.D., Eric A. Rose, M.D., Maryanne R. Kichuck, M.D.*, Linda J. Addonizio, M.D.* and Daphne T. Hsu, M.D.* New York, New York Discussant: Charles B. Huddleston, M.D.
At our institution, 134 pediatric heart transplants have been performed. Twenty patients had previously undergone a Fontan (17) or Glenn (3) procedure. Not only do these patients represent a significant operative challenge but they typically have multiple medical issues confounding their perioperative management. Co-morbid states present at the time of transplant are listed below. These surgical and medical issues are manifest by longer bypass times, 241 ± 67 vs. 147 + 64 minutes, longer hospital stays, 37 ± 37 vs. 27 ± 20 days, and higher thirty day mortality, 87% vs. 69%, in this high risk group as compared to the other 114 patients. However, all the patients in this cohort discharged from the hospital are still alive heralding a long-term survival equivalent to the non-Fontan group.
Operative strategies required flexibility in techniques to reconstruct the recipients' anatomy to afford an orthotopic heart transplant. The use of donor tissue, especially extra-length on the great vessels and pericardium, was characteristic of these reconstructions. Residual anatomic defects were manifest in 10 patients post-operatively: aortopulmonary collaterals (6), pulmonary A-V fistulae (3), branch pulmonary artery stenoses (2), coarctation (1). Pulmonary A-V fistulae all regressed spontaneously post-transplantation. All other defects were effectively managed in the invasive catheterization suite through embolization or dilatation. Although this patient cohort presents significant challenges operatively and during the immediate post-operative period they enjoy similar long-term survival as pediatric patients with less complex anatomy receiving heart transplants.
4:35 p.m. EXECUTIVE SESSION (Limited to Members)
6:30 p.m. MEMBER RECEPTION
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