Pediatric cardiac retransplantation: intermediate-term results.

BACKGROUND: Cardiac retransplantation (re-CTx) in children is a controversial therapy, yet it remains the best treatment option to recipients with failing grafts. Our objective was to determine the incidence of re-CTx in a large pediatric population of recipients and evaluate the outcome of such therapy. METHODS: Between November 1985 and November 1999, 347 children underwent cardiac transplantation at the Loma Linda University Medical Center. Of these, 32 children were listed for re-CTx. Ten patients died while waiting, and 22 recipients underwent re-CTx. Median age at re-CTx was 7.1 years (range, 52 days to 20.1 years). RESULTS: Indications for re-CTx were allograft vasculopathy (n = 16), primary graft failure (n = 5), and acute rejection (n = 1). Two patients with primary graft failure underwent retransplantation within 24 hours of the first transplantation procedure while on extracorporeal membrane oxygenation support. Median time interval to re-CTx for the others was 7.2 years (range, 32 days to 9.4 years). Operative mortality for all cardiac re-CTx procedures was 13.6%. Causes of hospital mortality were pulmonary hypertension with graft failure (n = 2) and multiorgan failure (n = 1). Median hospital stay after re-CTx was 14.1 days (range, 6 to 45 days). There was one late death from severe rejection. Actuarial survival at 3 years for re-CTx was 81.9% +/- 8.9% compared with 77.3% +/- 2.6% for primary cardiac transplantation recipients (p = 0.70). CONCLUSIONS: Elective re-CTx can be performed with acceptable mortality. Although the number of patients undergoing retransplantation in this report is small and their long-term outcome is unknown, the intermediate-term survival after re-CTx is similar to that of children undergoing primary cardiac transplantation.

Sutureless coronary artery bypass with biologic glued anastomoses: preliminary in vivo and in vitro results.

OBJECTIVE: As heart surgery becomes increasingly focused on minimally invasive techniques, it has become apparent that conventional techniques of anastomosis will need to be severely altered or abandoned. Toward that end, we developed and tested in vitro and in vivo coronary artery bypass graft anastomoses using a biologic glue formulated from bovine albumin and glutaraldehyde. We used a double-balloon catheter as a temporary internal stent to create and seal the anastomosis during gluing. METHODS: Initially, anastomoses were made between cryopreserved human saphenous vein segments and coronary arteries in vitro on 12 intact bovine hearts. A total of 42 anastomoses were created with the catheter system introduced into the distal end of the graft, exiting the back wall, and entering the anterior wall of the coronary artery. Two balloons (one in the graft and one in the coronary artery) held the anastomosis stable while the biologic glue was applied externally and allowed to set for 2 minutes. The balloon catheter was then removed from the end of the graft simulating a side-to-side internal thoracic artery anastomosis. After the graft had been flushed to assure distal end patency, the open end of the graft was clipped, turning the anastomosis into an end-to-side graft. A pressure transducer was then attached to the graft and saline solution forcefully infused. RESULTS: All grafts easily held a pressure of 300 mm Hg; 10 grafts were tested up to 560 mm Hg without leaks. Distal and proximal coronary artery patency was checked by examining flow out of the coronary ostia and by cutting arteries distal to the grafts. All anastomoses were patent on being opened and no glue was seen intraluminally. Subsequently, 3 anastomoses of the left internal thoracic artery to the left anterior descending artery have been constructed in goats, with autopsies at 24 hours, 10 months, and 1 year revealing patent anastomoses. CONCLUSION: A biologic glue and catheter system has been developed that allows a coronary anastomosis with a high bursting strength to be performed. When the system has been further developed and tested, truly minimally invasive heart surgery may be possible.

Repair of traumatic aortic rupture: a 25-year experience.

BACKGROUND: Surgical management of traumatic aortic rupture (TAR) is controversial, specifically whether distal aortic perfusion modifies the outcome. HYPOTHESIS: The outcome of patients who undergo repair of TAR is not dependent on the technique of repair. DESIGN: Retrospective review. SETTING: Tertiary care teaching hospital, level I regional trauma center. PATIENTS: One hundred fifteen victims (aged 5-81 years) of blunt chest trauma with aortic tear, presenting between January 1, 1974, and June 30, 1999. METHODS: Medical records were reviewed for prehospital and emergency department data, operative findings, and outcome. Statistical comparison was made using a paired 2-tailed t test. INTERVENTION: Surgical repair of TAR with (group 1) or without (group 2) distal aortic perfusion. RESULTS: Thirty-two patients in group 1 had TAR repair using active bypass (n = 18) or Gott shunt (n = 14). The clamp-and-sew technique was used in 83 patients (group 2). Primary repair was possible in 14 patients (44%) in group 1 and 69 patients (83%) in group 2. The average aortic cross-clamp time was 48 minutes for group 1 (range, 25-113 minutes) and 20 minutes for group 2 (range, 5-40 minutes) (P<.03). There was no significant difference in hospital mortality (6 [18.7%] of 32 vs 15 [18.1%] of 83) or the incidence of paraplegia (2 [6%] of 32 vs 5 [6%] of 83) between groups 1 and 2. During the last 15 years, 78 patients (73 in group 2) had repair of TAR with an operative mortality rate of 19.2%. CONCLUSIONS: Acute TAR remains a highly lethal injury with no change in prognosis during the last 2(1/2) decades. Repair of TAR using simple aortic cross-clamping alone is feasible in the majority of patients without increased mortality or spinal cord injury.

How to construct a monocusp valve.

Construction of a monocusp is an easy procedure that adds little, if any time to routine transannular patching of the right ventricular outflow tract. It also adds little cost to the operation when constructed from autologous pericardium. The monocusp's utility in preventing or lessening the impact of pulmonary regurgitation in the early postoperative period has been demonstrated. Its utility as a long-term pulmonary valve substitute will need to await longer-term clinical follow-up currently underway at our institution and others.

Successful myocardial volume reduction in a 9-month-old infant.

Left ventricular reduction has shown promise as a treatment for end-stage dilated cardiomyopathy, with restoration of the physiologic ratio between myocardial mass and left ventricular diameter. We present a case of successful partial left ventriculectomy utilizing both lateral and septal wall excision as treatment of dilated cardiomyopathy in a 9-month-old patient.

Ultra fast track in elective congenital cardiac surgery.

BACKGROUND: Changes in healthcare delivery have affected the practice of congenital cardiac surgery. We recently developed a strategy of limited sternotomy, early extubation, and very early discharge, and reviewed the perioperative course of 198 pediatric patients undergoing elective cardiovascular surgical procedures, to assess the efficacy and safety of this approach. METHODS: One hundred ninety-eight patients aged 0 to 18 years (median 3.2 years) underwent 201 elective cardiovascular surgical procedures over a 1-year period. All patients were admitted on the day of surgery. Patients were divided into six diagnostic groups: group 1, complex left-to-right shunts (n = 14, 7.0%); group 2, simple left-to-right shunts (n = 83, 41.3%); group 3, right-to-left shunts with pulmonary obstruction (n = 33, 16.4%); group 4, isolated, nonvalvular obstructive lesions (n = 30, 14.9%); group 5, isolated valvular anomalies (n = 20, 10.0%); and group 6, miscellaneous (n = 21, 10.4%). RESULTS: After 201 procedures, 175 patients (87.1%) were extubated in the operating room and 188 (93.6%) within 4 hours from operation. Four patients (2.0%) were extubated more than 24 hours from completion of the procedure, and 2 (1.0%) died while on respiratory support (never weaned). Five patients (2.6%) failed early extubation (<4 hours). Early discharge was achieved for the vast majority of patients. Overall median length of stay (LOS, including day of surgery as day 1) was 2.0 days, with a median LOS of 3.0 days for those patients requiring circulatory arrest duration exceeding 20 minutes. Of 195 patients, 43 (24.6%), 121 (74.0%), and 159 (81.5%) were discharged, respectively, at <24, <48, <72 hours from admission. Longest and shortest mean postoperative LOS were in group 6 (9.9+/-14.5 days) and group 2 (1.6 = 0.7 days), respectively. Six patients (2.9%) died, and 11 (5.5%) suffered in-hospital complications. Thirty patients (15.4%) were either treated as outpatients (n = 11, 5.7%) or readmitted (n = 19, 9.7%) within 30 days from the time of surgery. Only 8 of 195 patients (4.1%) were readmitted with true surgical complications requiring invasive therapeutic procedures. CONCLUSIONS: Selected patients with a broad spectrum of congenital heart disease may enjoy same-day admission, limited sternotomy, immediate extubation, and very early discharge with excellent outcomes and acceptable morbidity.

Minimally invasive approach for aortic arch branch vessel reconstruction.

Minimally invasive aortic arch branch vessel reconstruction was successfully accomplished in four patients over the past 3 years. There were no operative complications. Three patients had an uneventful hospital course, ranging from 3 to 5 days. The fourth patient with multiple medical problems and severe peripheral vascular disease had a prolonged hospital course for reasons unrelated to the surgical procedure. This minimally invasive surgical exposure can be used to effectively and safely repair innominate and left common carotid artery lesions.

Repair of acute descending aortic dissection complicated by visceral ischemia.

Visceral ischemia is a rare but lethal complication of type III aortic dissection. We report a Marfan patient with such a complication who had a complete resolution of profound visceral ischemia despite a delay in repair of over 48 hours.

Pulmonary Rhizopus rhizopodiformis cavitary abscess in a cardiac allograft recipient.

Pulmonary mucormycosis is rare in solid organ transplant recipients. Only one case has been reported previously in a cardiac allograft recipient. However, the Rhizopus species in that study was not identified. We report a case of successful surgical treatment of pulmonary cavitary mucormycosis due to Rhizopus rhizopodiformis in a cardiac allograft transplant recipient. A review of the literature on pulmonary mucormycosis occurring in solid organ transplant recipients is also presented.

Cardiac retransplantation for graft vasculopathy in children: should we continue to do it?

BACKGROUND: Cardiac transplantation (CTx) has been established as an effective therapy for a variety of inoperable cardiac conditions in infants and children. However, graft vasculopathy (GV) has emerged as the main limiting factor to long-term survival of CTx recipients. The only treatment of severe GV is cardiac retransplantation (re-Tx). Controversy exists regarding the use of scarce donor organs for cardiac re-Tx. OBJECTIVE: To compare the outcome of cardiac re-Tx for GV with that of primary CTx in children. DESIGN: A 12-year retrospective cohort review. SETTING: A university-affiliated children's hospital. PATIENTS: All infants and children who underwent CTx (group 1, n = 322) had complete follow-up of 1389.7 patient-years. Graft vasculopathy was confirmed in 32 recipients (1.1-8.2 years after undergoing CTx). Thirteen patients died suddenly, 3 died waiting for cardiac re-Tx (1-17 days after relisting), 4 are pending cardiac re-Tx, and 12 (group 2) underwent cardiac re-Tx. INTERVENTION: Cardiac re-Tx at a mean (+/- SD) interval from the first CTx of 6.3 +/- 1.8 years (range, 2.2-9.4 years). Two patients required additional aortic arch aneurysm repair with cardiac re-Tx. RESULTS: When group 1 was compared with group 2, there was no significant difference in operative mortality (9.0% vs 8.3%; P = .9), rejection rate (0.98 vs 0.86; P = .1), and hospital stay (23.0 +/- 18.8 days vs 20.5 +/- 11.6 days; P = .65). Actuarial survival for groups 1 and 2 at 1 and 4 years was 84.3% vs 83.3% (P = .59) and 74.4% vs 83.3% (P = .85), respectively. CONCLUSIONS: The surgical outcome and intermediate survival of cardiac re-Tx for GV and primary CTx are similar. Children with severe cardiac GV are at risk of sudden death and can benefit from early cardiac re-Tx.

Heart transplantation in infants and children with situs inversus.

BACKGROUND: Recipient situs inversus has always represented a technical challenge during heart transplantation. OBJECTIVE: A simplified operative strategy for heart transplantation in a recipient with atrial situs inversus is described. METHODS: Fifteen pediatric recipients with situs inversus accompanying other complex congenital heart disease or dilated cardiomyopathy having "orthotopic" heart allotransplantation in one center, between 1985 and 1997, were reviewed retrospectively. A nearly uniform, simplified technical approach to transplantation was used and is described. RESULTS: Fourteen of these recipients with complex malformations survived the transplantation. Morbidity relating to surgical technique has been limited to partial (n = 2) or complete (n = 1) late obstruction of superior vena caval drainage; each case was managed successfully by interventional cardiologic techniques. Actuarial survival after transplantation compares favorably with that among 290 infants and children with atrial situs solitus who underwent heart transplantation. CONCLUSIONS: Systemic atrial malposition, including situs inversus, does not limit successful heart transplantation by the simplified method described.

Seven-year follow-up of coronary artery bypasses performed with and without cardiopulmonary bypass.

BACKGROUND: There has been resurgent interest in coronary revascularization performed on the beating heart. Heretofore, there has been no long-term comparison of this technique to traditional coronary artery bypass with cardioplegia. OBJECTIVE: The purpose of this study was to provide a comparison of long-term survival and intervention-free outcome between patient groups subjected to coronary bypass accomplished with or without the use of cardiopulmonary bypass. METHOD: From June 1989 to July 1990, all patients treated for coronary revascularization by three surgeons were considered for coronary revascularization with the heart beating: 107 patients underwent coronary bypass on the beating heart, and 112 patients underwent revascularization with the aid of bypass with cardioplegia. Mean ages (65 +/- 10 years) and risk factors were identical. Patients operated on with the heart beating had 2.4 +/- 0.9 grafts versus 3.2 +/- 1.1 grafts for patients having cardiopulmonary bypass with cardioplegia. RESULTS: At 7-year follow-up, 86 of 107 (80%) patients operated on with the heart beating were alive versus 88 of 112 (79%) patients in whom cardiopulmonary bypass with cardioplegia was used. Cardiac deaths occurred in 13 of 107 (12%) patients in the former group versus 10 of 112 (9%) patients in the latter group. However, 32 of 107 patients operated on with the heart beating (30%) needed catheterization for their symptoms versus 18 of 112 (16%) patients in the bypass with cardioplegia group (p = 0.01). This results in 21 of 107 (20%) patients in the beating heart group needing angioplasty or a second coronary bypass versus only 8 of 112 (7%) patients in the bypass with cardioplegia group. No patient in the bypass with cardioplegia group required reoperation. Most of the reinterventions for the beating heart group were percutaneous transluminal coronary angioplasty (15 of 21 [71%] patients). CONCLUSION: Despite one less graft per patient, survival and cardiac death rates were similar for the two groups. However, twice as many patients in the beating heart group required recatheterization (30% versus 16%), and 20% needed a second intervention. Only 7% of the bypass with cardioplegia group required reintervention. Limited revascularization of the beating heart provides long-term results comparable to full revascularization with cardiopulmonary bypass, but at the cost of a threefold increase in reinterventions.

Prolonged discordant xenograft survival and delayed xenograft rejection in a pig-to-baboon orthotopic cardiac xenograft model.

OBJECTIVE: Our objectives were to study delayed xenograft rejection and the effectiveness of pretransplantation total lymphoid irradiation combined with immunosuppression on rejection in a pig-to-baboon cardiac xenograft model. METHODS: Baboons were treated with pretransplantation total lymphoid irradiation, cyclosporine A (INN: ciclosporin), and methotrexate. Orthotopic pig-to-baboon cardiac transplantations were performed after depletion of circulating xenoreactive natural antibody by pretransplantation donor organ hemoperfusion. Tissue samples were collected for immunologic and immunopathologic evaluation. RESULTS: Pig cardiac xenografts survived more than 18 and 19 days without evidence of hyperacute rejection. Immunologic analysis of serum samples demonstrated that circulating xenoreactive natural antibody levels did not return to pretransplantation levels. The production of xenoreactive natural antibodies from the recipient's splenocytes was inhibited completely. Histologic examination of xenografts showed the feature of acute vascular rejection. Immunohistochemical studies demonstrated infiltration of cardiac xenografts by large numbers of macrophages, small numbers of natural killer cells, and a few T cells. The infiltrating macrophages also showed expression of interleukin-1 and tumor necrosis factor. Diffuse deposition of immunoglobulin G, C1Q, C3, and fibrin on xenograft vasculature was observed. Interleukin-2 expression was not found in rejected cardiac xenografts. Xenograft endothelial cells also showed evidence of activation (expression of cytokines interleukin-1 and tumor necrosis factor). CONCLUSIONS: This study demonstrates prolonged discordant cardiac xenograft survival and delayed xenograft rejection in a pig-to-baboon model. The delayed xenograft rejection is mediated by both humoral and cellular mechanisms. Pretransplantation total lymphoid irradiation combined with cyclosporine A and methotrexate can inhibit xenoreactive natural antibody production but not elicited antipig antibody production and the xenoreactivity of macrophages.

Facile minimally invasive cardiac surgery via ministernotomy.

BACKGROUND: The public's and surgeons' perception of minimally invasive operations are frequently at odds. Nevertheless, real or perceived benefits may result from limiting skin and skeletal trauma. METHODS: Beginning in January 1996, we began approaching most infant and pediatric open heart procedures through an upper sternal split incision using a 1- to 3-inch skin opening and then extended this technique using a 2.5- to 3.5-inch incision for adult aortic and mitral valve replacement. RESULTS: A total of 82 patients, 57 infants and children and 25 adults, have been operated on using this approach (age range, newborn to 81 years). Operations accomplished through ministernotomy have included aortic valvotomy, arterial switch, tetralogy of Fallot, atrial or ventricular septal defect closure, aortic valve replacement, mitral valve replacement and repair, redo aortic or mitral valve replacement, double valve replacement, aortic root replacement, and complex arch reconstruction. In adults, the sternum was divided and then a T incision was made at the second, third, or fourth intercostal space. The mitral valve was reached through the roof of the left atrium. In children, a lower sternal split was used for atrial septal defect repairs. All cannulas were introduced through the ministernotomy incision, eliminating femoral cannulation. No new instruments, retractors, or ports were used. Mediastinal drainage was accomplished through a Blake drain connected to Heimlich-valved grenade suction. All but 2 patients were extubated immediately. Hospital stay was from 1 to 20 days (median 2 days). Patient and family acceptance is very high. CONCLUSIONS: On the basis of this initial experience, we attempt all congenital cardiac and isolated adult valve operations through ministernotomy.

Facile left ventricular deairing by administration of cardioplegia into the left ventricular vent.

De-airing of left heart structures during minimally invasive valve operations is often difficult. A method of using a left ventricular vent temporarily hooked to the cardioplegia cannula for facile left ventricular deairing is described. Routine use of this simple method coupled with transesophageal echocardiography monitoring simplifies the process of left ventricular deairing in minimally invasive or standard valvular operations.

Survival following orthotopic cardiac xenotransplantation between juvenile baboon recipients and concordant and discordant donor species: foundation for clinical trials.

It has been more than a decade since the last clinical trial of cardiac xenotransplantation in a newborn infant. Since that event, laboratory research at Loma Linda University has focused on survival studies of orthotopically xenografted juvenile baboon recipients. Both concordant and discordant donor species have been used. Transgenic donors have not been explored at Loma Linda. Instead, simplified host immunoregulative protocols, consistent with those used in neonatal cardiac allografting, have been adapted to xenotransplant research. Xenograft bridge to alloengraftment was evaluated in a series of five juvenile baboon recipients. Heterotopically implanted cardiac xenografts stimulated host production of xenoreactive antibody. Orthotopic cardiac allografting was then carried out. Xenoantibody appeared to play little role in immediate or chronic survival of experimental hosts. A clinical protocol of xenobridging to allotransplantation would likely succeed. Two consecutive series of orthotopically xenotransplanted hosts using rhesus monkey cardiac donors demonstrated unprecedented long-term survival. Splenectomy combined with maintenance therapy consisting of FK-506 and methotrexate contributed to survival of up to 502 days in one series of xenografted baboon hosts selected for ABO blood grouping, mixed lymphocyte culture, and crossmatch compatibility. Survival beyond a year (maximum 515 days) among three consecutive juvenile baboon recipients of orthotopically implanted rhesus monkey hearts, in which splenectomy was omitted and cyclosporine was substituted for FK-506, represents a benchmark achievement. Commencing maintenance immunosuppression several weeks prior to transplantation appeared to improve chronic survival significantly. Investigation of discordant (pig-to-baboon) host survival has focused on adsorption of naturally occurring xenoreactive antibody at the time of transplantation. This strategy, combined with pretransplant total lymphoid irradiation and both pre- and posttransplant immunosuppression, succeeded in preventing hyperacute rejection and resulted in survival of up to 24 days, thereby permitting observation of the delayed xenograft rejection phase. Data support consideration of additional clinical trials of concordant neonatal cardiac xenotransplantation and offer promise for the development of discordant xenotransplantation as an ultimate therapeutic resource.