RNA helicase, DDX27 regulates skeletal muscle growth and regeneration by modulation of translational processes

Gene expression in a tissue-specific context depends on the combined efforts of epigenetic, transcriptional and post-transcriptional processes that lead to the production of specific proteins that are important determinants of cellular identity. Ribosomes are a central component of the protein biosynthesis machinery in cells; however, their regulatory roles in the translational control of gene expression in skeletal muscle remain to be defined. In a genetic screen to identify critical regulators of myogenesis, we identified a DEAD-Box RNA helicase, DDX27, that is required for skeletal muscle growth and regeneration. We demonstrate that DDX27 regulates ribosomal RNA (rRNA) maturation, and thereby the ribosome biogenesis and the translation of specific transcripts during myogenesis. These findings provide insight into the translational regulation of gene expression in myogenesis and suggest novel functions for ribosomes in regulating gene expression in skeletal muscles.

Loss of catalytically inactive lipid phosphatase myotubularin-related protein 12 impairs myotubularin stability and promotes centronuclear myopathy in zebrafish

X-linked myotubular myopathy (XLMTM) is a congenital disorder caused by mutations of the myotubularin gene, MTM1. Myotubularin belongs to a large family of conserved lipid phosphatases that include both catalytically active and inactive myotubularin-related proteins (i.e., "MTMRs"). Biochemically, catalytically inactive MTMRs have been shown to form heteroligomers with active members within the myotubularin family through protein-protein interactions. However, the pathophysiological significance of catalytically inactive MTMRs remains unknown in muscle. By in vitro as well as in vivo studies, we have identified that catalytically inactive myotubularin-related protein 12 (MTMR12) binds to myotubularin in skeletal muscle. Knockdown of the mtmr12 gene in zebrafish resulted in skeletal muscle defects and impaired motor function. Analysis of mtmr12 morphant fish showed pathological changes with central nucleation, disorganized Triads, myofiber hypotrophy and whorled membrane structures similar to those seen in X-linked myotubular myopathy. Biochemical studies showed that deficiency of MTMR12 results in reduced levels of myotubularin protein in zebrafish and mammalian C2C12 cells. Loss of myotubularin also resulted in reduction of MTMR12 protein in C2C12 cells, mice and humans. Moreover, XLMTM mutations within the myotubularin interaction domain disrupted binding to MTMR12 in cell culture. Analysis of human XLMTM patient myotubes showed that mutations that disrupt the interaction between myotubularin and MTMR12 proteins result in reduction of both myotubularin and MTMR12. These studies strongly support the concept that interactions between myotubularin and MTMR12 are required for the stability of their functional protein complex in normal skeletal muscles. This work highlights an important physiological function of catalytically inactive phosphatases in the pathophysiology of myotubular myopathy and suggests a novel therapeutic approach through identification of drugs that could stabilize the myotubularin-MTMR12 complex and hence ameliorate this disorder.

The zebrafish dag1 mutant: a novel genetic model for dystroglycanopathies

In a forward genetic approach to identify novel genes for congenital muscle diseases, a zebrafish mutant, designated patchytail, was identified that exhibits degenerating muscle fibers with impaired motility behavior. Genetic mapping identified a genomic locus containing the zebrafish ortholog of the dystroglycan gene (DAG1). Patchytail fish contain a point mutation (c.1700T>A) in dag1, resulting in a missense change p.V567D. This change is associated with reduced transcripts and a complete absence of protein. The absence of α-dystroglycan and β-dystroglycan caused destabilization of dystroglycan complex, resulting in membrane damages. Membrane damage was localized on the extracellular matrix at myosepta as well as basement membrane between adjacent myofibers. These studies also identified structural abnormalities in triads at 3 days post fertilization (dpf) of dystroglycan-deficient muscles, significantly preceding sarcolemmal damage that becomes evident at 7 dpf. Immunofluorescence studies identified a subpopulation of dystroglycan that is expressed at t-tubules in normal skeletal muscles. In dag1-mutated fish, smaller and irregular-shaped t-tubule vesicles, as well as highly disorganized terminal cisternae of sarcoplasmic reticulum, were common. In addition to skeletal muscle defects, dag1-mutated fish have brain abnormalities and ocular defects in posterior as well as anterior chambers. These phenotypes of dystroglycan-deficient fish are highly reminiscent of the phenotypes observed in the human conditions muscle-eye-brain disease and Walker-Warburg syndrome. This animal model will provide unique opportunities in the understanding of biological functions of dystroglycan in a wide range of dystroglycanopathies, as disruption of this gene in higher vertebrates results in early embryonic lethality.

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.

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.

Right ventricular outflow tract reconstruction using a Goretex membrane monocusp valve in infant animals

We examined the feasibility of using a polytetrafluoroethylene membrane (goretex) valve and transannular patch (TAP) for right ventricular outflow tract (RVOT) reconstruction in growing animal models. Eleven infant goats (Group A) and 12 infant sheep (Group B) underwent RVOT reconstruction under cardiopulmonary bypass. In Group A, a monocusp valve was constructed of goretex, and the RVOT was roofed over utilizing a TAP of bovine pericardium. In Group B, both a monocusp valve and a TAP were constructed of goretex. Animals were sacrificed at 6 or 12 postoperative months. Two goats in Group A died at 9 days and 4 months postoperatively due to RVOT obstruction caused by thrombus formation. Seven goats in Group A and 11 in Group B showed no pressure gradient across the valve. All animals in Group B revealed mild to moderate valvular insufficiency, but no ventricular deterioration. In contrast to the bovine pericardium, which showed a prominent fibroinflammatory reaction with calcified areas causing TAP shrinkage and RVOT stenosis, there was minimal calcification and inflammatory reaction directed against the goretex valve and TAP. We conclude that goretex can be used as a material from which to create both a monocusp valve and TAP for long-term RVOT reconstruction.

Emergency implantation of a left ventricular assist device in adolescents with biventricular failure

Adolescents with congestive cardiomyopathy who present with intractable arrhythmia or progressive ventricular failure have a very poor prognosis and often die awaiting cardiac transplantation (CTx). We present our recent experience with a pneumatically powered left ventricular assist device (LVAD) implanted emergently to salvage adolescents with severe biventricular failure. Four patients, aged 15-17 years, body surface areas of 1.5-1.7 m2, with dilated cardiomyopathy (LV diastolic dimension, 7.1-8.3 cm); two presented with cardiovascular collapse, one with refractory ventricular tachycardia, and one with cardiac arrest. Hemodynamic and biochemical data before and 1 week after LVAD placement are expressed as mean and range values. None of the patients required right ventricular assist, and all patients achieved functional recovery while on LVAD support (8-71 days). Currently, all four patients are alive (11-22 months) after successful CTx. We conclude that emergency implantation of an LVAD in adolescents with biventricular heart failure can be life saving. As has been shown in the adult population, such a ventricular assist system restores normal circulatory hemodynamics, reverses multi-organ dysfunction, and provides a "safe" bridge to transplantation.

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.

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.

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.

Heart transplantation for hypoplastic left heart syndrome: modified technique for reducing circulatory arrest time

BACKGROUND

The surgical technique of heart transplantation as therapy in infants with hypoplastic left heart syndrome was first reported over a decade ago. Since that time, incremental refinements have evolved that both facilitate the operation and potentially reduce the perceived neurologic hazards associated with the use of hypothermic circulatory arrest.

METHODS

Minor technical adjustments have permitted infant heart transplantation to be accomplished with relative ease while markedly limiting the need for complete circulatory arrest. Low-flow hypothermic systemic perfusion is used for atrial implantation, reserving circulatory arrest for arch reconstruction only. This is accomplished by use of an active (pump) sucker for venous return.

RESULT

Mean circulatory arrest time with the current technique has been 26 minutes.

CONCLUSION

Minor technical refinements have resulted in a marked reduction in hypothermic circulatory arrest time during infant heart transplantation for hypoplastic left heart syndrome.

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.

Posttransplant recoarctation of the aorta: a twelve year experience

OBJECTIVES

This study was undertaken to investigate the incidence of posttransplant recoarctation of the aorta, delineate the mode of presentation, identify risk factors that predict recoarctation and examine the results of intervention for posttransplant recoarctation.

BACKGROUND

Patients with aortic arch hypoplasia require extended arch reconstruction at transplant, with an inherent possibility of subsequent recoarctation of the aorta.

METHODS

This was a retrospective review of all children (age <18 years) who underwent cardiac transplantation over a 10-year period. Collected data included pretransplant diagnosis, details of the transplant procedure and posttransplant data including development of recoarctation of the aorta, interventions for recoarctation and the most recent follow-up assessment of the aortic arch.

RESULTS

Two hundred eighty-eight transplants were performed on 279 children (follow-up = 1,075 patient-years; range 0 to 133 months, median 43.7). Thirty-two of 152 patients (21%) who underwent extended aortic arch reconstruction subsequently developed recoarctation. All but one patient developed recoarctation within 2 years after transplant; 87% were hypertensive at presentation. Of 30 patients who underwent intervention for recoarctation (balloon angioplasty [n = 26] and surgical repair of recoarctation [n = 4]), 26 (87%) have remained recurrence-free (follow-up = 133 patient-years; range 8 to 106 months, median 47).

CONCLUSIONS

The high frequency of recoarctation after cardiac transplantation with extended aortic arch reconstruction mandates serial echocardiographic evaluation of the aortic arch. Patients typically present with systemic hypertension within the first two years after transplantation. Balloon angioplasty is a safe, effective and durable method of treatment.

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.

Limitations to survival for infants with hypoplastic left heart syndrome before and after transplant: the Loma Linda experience

Untreated, hypoplastic left heart syndrome is a lethal cardiac defect. Heart transplant has become an accepted therapeutic option for this condition. However, significant limitations to survival remain for infants with this condition who are referred for heart transplantation. Attention to the prevention, early detection, and management of common problems occurring at each stage of the transplantation process is important for improving survival rates. This study retrospectively reviewed the cases of 195 infants with hypoplastic left heart syndrome registered for heart transplantation at Loma Linda University Medical Center between November 1985 and July 1996 to determine causes of death. During the waiting period, progressive cardiac failure and complications from interventional procedures were the leading causes. In the early postoperative period, technical issues and acute graft failure were most important, whereas late deaths (more than 30 days after transplant) were most often related to rejection and posttransplant coronary artery disease.

Prolonged discordant cardiac xenograft survival in newborn recipients

BACKGROUND

We previously demonstrated very low levels of xenoreactive natural antibodies in newborns, suggesting the possibility of prolongation of xenograft survival in newborn recipients. We used a pig-to-newborn goat heterotopic cardiac xenograft model to examine our hypothesis that hyperacute rejection would be absent in newborn recipients and that both humoral and cellular rejection would participate in the late phase of discordant xenograft rejection.

METHODS AND RESULTS

The serum of newborn goats was found to have very low titers of natural anti-pig antibodies. Newborn pig hearts were transplanted heterotopically into the neck of four unmanipulated newborn goats: none of these xenografts underwent hyperacute rejection. Dilation of the xenografts and decreased contractility were observed 4 to 6 days after transplantation, and the xenografts eventually ceased functioning between 6 and 8 days after transplantation. Blood samples collected after transplantation demonstrated a dramatic increase in anti-pig xenoantibody titers and correlated with histological studies demonstrating features consistent with delayed humoral rejection, including reactive vascular endothelial and perivascular stromal cells, marked capillary congestion, and interstitial hemorrhages. Scant to diffuse perivascular and interstitial infiltration of activated lymphoid cells occurred.

CONCLUSIONS

Our study demonstrates that hyperacute rejection does not occur, allowing limited prolongation of xenograft survival in a pig-to-newborn goat cardiac xenograft model. We propose that this is attributable, at least in part, to the very low titers of natural antibodies in newborn recipients. Delayed xenograft rejection, however, remains an important problem in these newborn recipients. This delayed xenograft rejection is likely the result of both humoral and cellular rejection mechanisms.

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.

The optimal Fontan connection: a growing extracardiac lateral tunnel with pedicled pericardium

OBJECTIVE

The concept of a lateral tunnel for the Fontan operation is now widely accepted. Most lateral tunnels are constructed intraatrially with the use of aortic crossclamping. Construction of extracardiac lateral tunnels with the use of homografts or other nonviable tubes eliminates aortic crossclamping but lacks growth potential in length or width. The native pericardium, which is "sealed" posteriorly along the pulmonary artery, atrium, and inferior vena cava, could be turned down onto the right atrium to form a viable extracardiac lateral tunnel.

METHODS

We designed and successfully constructed extracardiac lateral tunnels using viable autologous pericardium, pedicled on its lateral blood supply, in 19 patients aged 9 months to 5 years. All patients had a previous Glenn shunt; five patients had dextrocardia and a midline inferior vena cava. The patients' inferior vena cava-right atrial connection was opened transversely and the right atrial opening was sutured to its back wall, keeping the eustachian valve in the inferior vena cava. The underside of the right pulmonary artery was opened longitudinally; its inferior edge was sewn to the adjacent pericardial reflection. Any "pocket" or depressions in the posterior pericardium along the pulmonary veins were closed with running suture. Two incisions were made in the right pericardium down to the phrenic nerve parallel to the inferior vena caval and pulmonary arterial openings. This pedicled pericardium was trimmed and sewn as a roof to the upper edges of the inferior vena cava and pulmonary artery openings and then sewn longitudinally along the unopened right atrial wall, completing the viable extracardiac lateral tunnel. Although no fenestrations were used, these could be made during construction, or more significantly, owing to the lack of thick walled structures, in the catheterization laboratory in the postoperative period.

RESULTS

All 19 patients had respiratory/cardiac pulsations in the pulmonary arteries owing to the compressible lateral tunnel. At follow-up of up to 2 1/2 years, all tunnels are growing and no obstructions have occurred.

CONCLUSION

The viable autologous pericardial extracardiac lateral tunnel can be constructed without cardiac ischemia, can be fenestrated in the postoperative period, and forms a compressible, nonthrombogenic conduit capable of growth, which can be constructed early in infancy.

Echocardiographic recognition of iatrogenic aortic valve leaflet perforation

BACKGROUND

There is a paucity of literature regarding iatrogenic aortic valve perforation after cardiac operations performed in the vicinity of the aortic valve. This report describes the echocardiographic recognition of iatrogenic aortic valve perforation.

METHODS

Among 6 patients who had previously under-gone non-aortic valve cardiac operations, a diagnosis of iatrogenic aortic regurgitation was made by transthoracic two-dimensional echocardiography and Doppler color flow imaging.

RESULTS

The location of the aortic valve leaflet perforation varied and depended on the site of the previous intracardiac lesion repair. Repeat operations in 5 patients confirmed the echocardiographic findings. Aortic valve repair was confirmed in 2 patients by transesophageal echocardiography, whereas aortic valve replacement became necessary in 2 other patients. A fifth patient with acquired cardiomyopathy underwent orthotopic heart transplantation.

CONCLUSIONS

A detailed two-dimensional echocardiographic examination, along with color flow imaging, should be done to evaluate iatrogenic aortic valve perforation in patients with a new murmur of aortic regurgitation after cardiac operations in proximity to the aortic valve. Precise preoperative diagnosis of this lesion allows optimal surgical planning and treatment.

Is there a safe limit to coronary sinus pressure during retrograde cardioplegia?

Although retrograde cardioplegia (RC) delivered via the coronary sinus (CS) is now used routinely, the pressure at which RC can be safely delivered is thought to be 50 to 60 mm Hg. Such practice is based on experiments performed on working, beating hearts with CS ligation and arterial inflow into both the coronary arteries and veins (Beck procedure). However, no data exist on arrested, vented hearts, as occurs clinically during RC. We studied the acute effect of 10 cc/kg of blood RC delivered into the CSs of 16 adult vented pig hearts, which were randomly assigned to four groups of four hearts each according to the CS pressure maintained during perfusion: 40, 80, 100, and 120 mm Hg. After RC, hearts were excised, cut in bread-loaf sections, examined grossly, and then fixed and stained. Sections of right ventricle, septum, and left ventricle were then examined by two blinded cardiac pathologists and two blinded surgeons and scored for the presence of extravascular hemorrhage. None of the 16 hearts tested showed any evidence of gross or microscopic hemorrhage; all hearts showed normal myocardial preservations and structure, including all hearts at 100 and 120 mm Hg CS perfusion pressure. We conclude that CS pressures up to 120 mm Hg cause no extravasation of blood into the myocardium in the vented, arrested heart. These results contradict studies on the working, beating heart, and suggest that high pressures in the CS are well tolerated during RC.

The use of transesophageal echocardiography to guide sternal division for cardiac operations via mini-sternotomy

Cardiac surgery utilizing the mini-sternotomy technique offers many advantages, including lessened pain and hospitalization. Mid-line upper sternotomy (or mini-sternotomy) can provide adequate exposure of the ascending aorta, the aortic root, the right atrial appendage and the dome of the left atrium. Inherent in providing adequate exposure is the level at which the sternum is "T'd" off. The lower aspect of the sternotomy is "T'd" off at the second, third, or fourth intercostal space depending on the patient's anatomy. We describe a technique that uses transesophageal echocardiography to determine the precise location for "T'ing" off the sternotomy, rather than approximating the sternotomy site by physical exam and chest radiograph. This technique will reliably delineate the sternotomy site, irrespective of a patient's body size and habitus.

Reanimation: overcoming objections and obstacles to organ retrieval from non-heart-beating cadaver donors

Interest in the retrieval of organs from non-heart-beating cadaver donors has been rekindled by the success of transplantation of solid organs and the insufficient supply of donor organs currently obtained from heart-beating cadaver donors. There are currently two retrieval techniques being evaluated, the in situ cold perfusion approach and the controlled death approach. Both, however, raise ethical concerns. Reanimation is a new method which has been used successfully in animals. We believe this new approach overcomes the ethical objections raised to these other methods.

The use of larger size pulmonary homografts for the Ross operation in children

Nine pediatric patients received an adult size cryopreserved pulmonary homograft for right ventricular outflow tract reconstruction as part of the Ross procedure. The early postoperative results are excellent. It is suggested that a full, adult size pulmonary homograft should be used in the future in pediatric patients undergoing the Ross procedure.

Transplantation as a primary treatment for hypoplastic left heart syndrome: intermediate-term results

BACKGROUND

Hypoplastic left heart syndrome is a lethal malformation. For the last 10 years, orthotopic cardiac transplantation has been our preferred treatment for infants with hypoplastic left heart syndrome.

METHODS

One hundred seventy-six infants with hypoplastic left heart syndrome were entered into a cardiac transplant protocol between November 1985 and November 1995. Interventional procedures to stent the ductus arteriosus or enlarge the interatrial communication were performed in 8 and 35 patients, respectively. Thirty-four patients (19%) died during the waiting period, and 142 infants underwent cardiac transplantation. Age at cardiac transplantation ranged from 1.5 hours to 6 months (median, 29 days). The majority of grafts were oversized, and the median graft ischemic time was 273 minutes (range, 60 to 576 minutes). The implantation procedure used a period of hypothermic circulatory arrest ranging from 23 to 110 minutes (median, 53 minutes). Repair of other significant defects included interrupted aortic arch and total or partial anomalous pulmonary venous connection.

RESULTS

There were 13 early and 22 late deaths. Patient actuarial survival at 1 month and at 1, 5 and 7 years was 91%, 84%, 76%, and 70% respectively. Half of the late deaths were due to rejection. Severe graft vasculopathy was confirmed in 8 patients. Retransplantation was performed in 5 patients for graft vasculopathy 4 and rejection 1. Lymphoblastic leukemia developed in 1 patient 3 years after cardiac transplantation.

CONCLUSIONS

Cardiac transplantation can be performed in infants with hypoplastic left heart syndrome with good operative and intermediate-term results. Improved survival can be achieved with increased donor availability, better management of rejection, and control of graft vasculopathy.

Neurologic sequelae of deep hypothermic circulatory arrest in cardiac transplant infants

BACKGROUND

Considerable controversy exists experimentally and clinically regarding adverse neurologic effects that may follow deep hypothermic circulatory arrest. Moreover, the techniques of DHCA have never been standardized.

METHODS

We prospectively studies the neurodevelopmental outcome in 38 infants undergoing cardiac transplantation using DHCA before the age of 4 months (mean age, 37.0 days). Neurodevelopmental outcome in the 22 boys and 16 girls was tested up to 2.5 years after transplantation using Bayley scale of infant development. Bayley scores were compared with the rate of core cooling and the length of DHCA in all patients. Deep hypothermic circulatory arrest was accomplished using an asanguineous prime resulting in hematocrits of 5% +/- 5% and ionized Ca2+, 0.4 +/- 0.1 mmol/L. No surface precooling was used, but the head was packed in ice. Mean cooling time was 14.0 +/- 3.5 minutes, resulting in rectal temperatures of 18 degrees +/- 2.5 degrees C. Duration of DHCA ranged from 42 to 70 minutes (mean duration, 56.0 +/- 6.6 minutes).

RESULTS

Postoperatively, the mean Bayley psychomotor development index was 91 (range, 50 to 130) and mental development index was 88 (range, 50 to 130). No relationship was found between either the rate of cooling or the duration of DHCA and Bayley scores (r = 0.227 and r = 0.322, respectively).

CONCLUSIONS

These data suggest that neither the rate of cooling nor DHCA times between 42 and 70 minutes using profoundly low hematocrits and low ionized calcium levels has any measurable effect on neurologic outcome up to 2.5 years postoperatively. It is possible that adverse neurologic outcomes from DHCA reflect particular methods of achieving DHCA.

Delayed primary repair of intrathoracic esophageal perforation: is it safe?

The management of intrathoracic esophageal perforation with delayed diagnosis is a subject of controversy. Because of the obvious advantages of primary repair as a simple single-stage operation, this technique was preferentially used to treat 18 of 22 consecutive patients with esophageal perforation. These patients were stratified into three groups according to the time interval between perforation and repair: group A, less than 6 hours, five patients (28%); group B, 6 to 24 hours, six patients (33%); and group C, more than 24 hours, seven patients (39%). Group A patients were older (p < 0.05) and group B had fewer iatrogenic perforations (B, 17%; A, 80%; C, 57%, p < 0.1). Additional tissue was used to buttress the repair site in all three groups (A, 3/5 patients, 60%; B, 4/6 patients, 67%; C, 6/7 patients, 86%; p = not significant). In seven patients (39%), a fundic wrap was used to reinforce the site of primary repair. The outcomes of the three groups were analyzed. Group A had the lowest proportion of postoperative leaks (A, 0/4 patients, 0%; B, 4/6 patients, 67%; C, 5/6 patients, 83%; p < 0.05) and postoperative morbidity (A, 2/5 patients, 40%; B, 6/6 patients, 100%; C, 6/7 patients, 86%; p < 0.1). However the increased incidence of leak and morbidity did not lead to an increase in mortality. One death occurred in each group, with an overall mortality of 17% (A, 1/5 patients, 20%; B, 1/6 patients, 17%; C, 1/7 patients, 14%; p = not significant). We conclude that in the era of advanced intensive care capabilities, primary repair of intrathoracic esophageal perforation can be safely accomplished in most patients regardless of the time interval between perforation and operation. Leakage at the suture site is common unless primary repair is carried out without delay. Postoperative leakage, however, is usually inconsequential and does not necessarily result in an adverse outcome.

Uniformity of perfusion in all regions of the human heart by warm continuous retrograde cardioplegia

BACKGROUND

Animal models have suggested that retrograde cardioplegia may be poorly distributed to septal and right ventricular regions of the heart; if true, this may have dangerous implications for warm continuous retrograde cardioplegia in humans. We have previously shown that blood gases from coronary arteries during warm continuous retrograde cardioplegia represent postcapillary "venous" gases and are reflective of myocardial perfusion.

METHODS

To determine regional differences in perfusion during warm continuous retrograde cardioplegia we obtained blood gases from three regions of the heart in 141 consecutive patients undergoing coronary artery bypass grafting, aortic valve replacement, or both. Right heart perfusion was determined by blood gases from the right coronary artery orifice, acute marginal, or posterior descending coronary arteries; circumflex or lateral wall perfusion was determined by samples from obtuse marginal or intermediate coronary arteries; and anterior wall/septal perfusion was determined by left anterior descending and diagonal coronary artery blood gases. Warm continuous retrograde cardioplegia flow ranged from 150 to 300 mL/min depending on heart size. A mean of 4 +/- 1 samples/patient were obtained.

RESULTS

There were no regional differences in postcapillary pH, carbon dioxide tension, or CO2 production during warm continuous retrograde cardioplegia. Oxygen tensions were lower in the right and anterior/septal regions of the heart, implying more O2 uptake. No regional acidosis, consistent with poor perfusion, could be detected.

CONCLUSIONS

We conclude that, unlike experimental models, regional myocardial perfusion, including the right heart, is uniform during "high-flow" warm continuous retrograde cardioplegia in humans.

Ventricular remodeling following infant-pediatric cardiac transplantation. Does age at transplantation or size disparity matter?

Early left ventricular (LV) remodeling following pediatric cardiac transplantation has not been described. To identify patterns and determinants of change in left ventricular mass and volume posttransplant, we studied 125 consecutive children who underwent cardiac transplantation between January 1, 1989 and July 31, 1993. Two-dimensional imaging-directed M-mode echocardiograms were studied weekly until 26 weeks post-transplant. LV mass and volume (indexed to BSA1.5) were measured. LV mass index increased until 3 weeks post-transplant, and then decreased. The mean decrement in LV mass index after 8 weeks post-transplant (relative to baseline) was significantly larger in patients with donor-recipient weight ratio > 1.5 compared with patients with donor-recipient weight ratio < or = 1.5 (-2.2 g/m3 compared with 33.4 g/m3, respectively, P < 0.01). Multiple linear regression was performed employing donor-recipient weight ratio, time since transplantation, ischemic time, and age at transplant as prognostic variables. Donor-recipient weight ratio (P < 0.0001), time since transplant (P < 0.01), and age at transplant (P = 0.02) were identified as independent predictors of change in LV mass index. Donor-recipient weight ratio (P = 0.001) and time since transplantation (P = 0.02) were independent predictors of change in LV volume index. There was an interaction between donor-recipient weight ratio and time since transplantation, suggesting that donor-recipient weight ratio has an independent effect as well as a time-dependent effect on change in LV mass and volume indices. LV mass and volume indices increased early posttransplant and then decreased; this pattern was temporally predictable, and dependent on donor-recipient weight ratio and age at transplant.

Growth of oversized grafts in neonatal heart transplantation

BACKGROUND

Because of the severe shortage of neonatal organ donors, oversized cardiac allografts are frequently transplanted. This study examined body and graft growth of neonates who receive an oversized heart.

METHODS

We studied 51 neonates, who received transplants between November 1986 and August 1992, for changes in body weight, left ventricular mass, and end-diastolic volume measured at 1 week, 1, 3, and 6 months, and yearly after cardiac transplantation. Patients were divided into two groups according to donor/recipient weight ratios: the normal group, where the donor/recipient weight ratio was 1.5 or less (1.06 +/- 0.05; n = 24), and the oversized group, where the donor/recipient weight ratio was more than 1.5 (2.22 +/- 0.10; n = 27).

RESULTS

After cardiac transplantation, body weight increased continuously in both groups with no difference between groups. In the oversized group, left ventricular end-diastolic volume at 1 week and left ventricular mass at 1 week and 1 month were significantly higher than those in the normal group (p < 0.01). In the normal group, end-diastolic volume and left ventricular mass increased continuously. In the oversized group, however, left ventricular mass significantly decreased until 3 months after cardiac transplantation and then increased continuously, whereas end-diastolic volume increased continuously throughout the posttransplantation period.

CONCLUSIONS

These data suggest that oversized cardiac allografts shrink at first and then grow as the recipient grows. There appears to be a size adaptation of the large cardiac allograft to accommodate to the reduced requirements of the neonate.

One-stage primary repair of distal esophageal perforation using fundic wrap

Esophageal leak following primary repair of esophageal perforation is a serious complication that can lead to severe mediastinitis and sepsis. Complete diversion with esophageal exclusion or resection is designed to minimize further mediastinal contamination. However, this approach is not necessarily associated with less morbidity or mortality. Furthermore, a second stage operation is required to restore esophageal continuity. From 1986 to 1994, we performed a one-stage primary repair of the distal esophagus in seven patients with either iatrogenic (n = 5) or spontaneous (n = 2) perforations and reinforced the repair by a fundic wrap. One patient underwent an additional modified Heller myotomy for achalasia. Delay between perforation and operation was less than 6 hours in 3 patients, 6 to 24 hours in 2 patients, and greater than 24 hours in 2 patients. Only one patient (14%) developed a small esophageal leak that spontaneously resolved with adequate mediastinal drainage, intravenous antibiotics, and aggressive nutritional support. One patient (14%), whose repair was delayed by 12 hours, died postoperatively of profound sepsis. This patient was moribund from sepsis preoperatively, and postmortem examination of the esophagus revealed no evidence of esophageal leak. Esophageal continuity was maintained in all patients. The median length of stay was 21 days (range, 15-58 days). We conclude that primary reinforced repair of esophageal perforation using a fundic wrap is an effective method of treatment for distal esophageal perforation, even when the repair is delayed by more than 24 hours.