Making a Difference: 5 Years of Cardiac Surgery Intersociety Alliance (CSIA).

Informed by the almost unimaginable unmet need for cardiac surgery in the developing regions of the world, leading surgeons, cardiologists, editors in chief of the major cardiothoracic journals as well as representatives of medical industry and government convened in December 2017 to address this unacceptable disparity in access to care. The ensuing "Cape Town Declaration" constituted a clarion call to cardiac surgical societies to jointly advocate the strengthening of sustainable, local cardiac surgical capacity in the developing world. The Cardiac Surgery Intersociety Alliance (CSIA) was thus created, comprising The Society of Thoracic Surgeons (STS), the American Association for Thoracic Surgery (AATS), the Asian Society for Cardiovascular and Thoracic Surgery (ASCVTS), the European Association for Cardio-Thoracic Surgery (EACTS) and the World Heart Federation (WHF). The guiding principle was advocacy for sustainable cardiac surgical capacity in low-income countries. As a first step, a global needs assessment confirmed rheumatic heart disease as the overwhelming pathology requiring cardiac surgery in these regions. Subsequently, CSIA published a request for proposals to support fledgling programs that could demonstrate the backing by their governments and health care institution. Out of 11 applicants, and following an evaluation of the sites, including site visits to the 3 finalists, Mozambique and Rwanda were selected as the first Pilot Sites. Subsequently, a mentorship and training agreement was completed between Mozambique and the University of Cape Town, a middle-income country with a comparable burden of rheumatic heart disease. The agreement entails regular video calls between the heart teams, targeted training across all aspects of cardiac surgery, as well as on-site presence of mentoring teams for complex cases with the strict observance of "assisting only." In Rwanda, Team Heart, a US and Rwanda-based non-governmental organization (NGO) that has been performing cardiac surgery in Rwanda and helping to train the cardiac surgery workforce since 2008, has agreed to continue providing mentorship for the local team and to assist in the establishment of independent cardiac surgery with all that entails. This involves intermittent virtual conferences between Rwandan and US cardiologists for surgical case selection. Five years after CSIA was founded, its "Seal of Approval" for the sustainability of endorsed programs in Mozambique and Rwanda has resulted in higher case numbers, a stronger government commitment, significant upgrades of infrastructure, the nurturing of generous consumable donations by industry and the commencement of negotiations with global donors for major grants. Extending the CSIA Seal to additional deserving programs could further align the international cardiac surgical community with the principle of local cardiac surgery capacity-building in developing countries.

Making a difference: 5 years of Cardiac Surgery Intersociety Alliance (CSIA).

Informed by the almost unimaginable unmet need for cardiac surgery in the developing regions of the world, leading surgeons, cardiologists, editors in chief of the major cardiothoracic journals as well as representatives of medical industry and government convened in December 2017 to address this unacceptable disparity in access to care. The ensuing "Cape Town Declaration" constituted a clarion call to cardiac surgical societies to jointly advocate the strengthening of sustainable, local cardiac surgical capacity in the developing world. The Cardiac Surgery Intersociety Alliance (CSIA) was thus created, comprising The Society of Thoracic Surgeons (STS), the American Association for Thoracic Surgery (AATS), the Asian Society for Cardiovascular and Thoracic Surgery (ASCVTS), the European Association for Cardio-Thoracic Surgery (EACTS) and the World Heart Federation (WHF). The guiding principle was advocacy for sustainable cardiac surgical capacity in low-income countries. As a first step, a global needs assessment confirmed rheumatic heart disease as the overwhelming pathology requiring cardiac surgery in these regions. Subsequently, CSIA published a request for proposals to support fledgling programs that could demonstrate the backing by their governments and health care institution. Out of 11 applicants, and following an evaluation of the sites, including site visits to the 3 finalists, Mozambique and Rwanda were selected as the first Pilot Sites. Subsequently, a mentorship and training agreement was completed between Mozambique and the University of Cape Town, a middle-income country with a comparable burden of rheumatic heart disease. The agreement entails regular video calls between the heart teams, targeted training across all aspects of cardiac surgery, as well as on-site presence of mentoring teams for complex cases with the strict observance of "assisting only." In Rwanda, Team Heart, a US and Rwanda-based nongovernmental organization (NGO) that has been performing cardiac surgery in Rwanda and helping to train the cardiac surgery workforce since 2008, has agreed to continue providing mentorship for the local team and to assist in the establishment of independent cardiac surgery with all that entails. This involves intermittent virtual conferences between Rwandan and US cardiologists for surgical case selection. Five years after CSIA was founded, its "Seal of Approval" for the sustainability of endorsed programs in Mozambique and Rwanda has resulted in higher case numbers, a stronger government commitment, significant upgrades of infrastructure, the nurturing of generous consumable donations by industry and the commencement of negotiations with global donors for major grants. Extending the CSIA Seal to additional deserving programs could further align the international cardiac surgical community with the principle of local cardiac surgery capacity-building in developing countries.

Making a difference: 5 years of Cardiac Surgery Intersociety Alliance (CSIA).

Informed by the almost unimaginable unmet need for cardiac surgery in the developing regions of the world, leading surgeons, cardiologists, editors in chief of the major cardiothoracic journals as well as representatives of medical industry and government convened in December 2017 to address this unacceptable disparity in access to care. The ensuing "Cape Town Declaration" constituted a clarion call to cardiac surgical societies to jointly advocate the strengthening of sustainable, local cardiac surgical capacity in the developing world. The Cardiac Surgery Intersociety Alliance (CSIA) was thus created, comprising The Society of Thoracic Surgeons (STS), the American Association for Thoracic Surgery (AATS), the Asian Society for Cardiovascular and Thoracic Surgery (ASCVTS), the European Association for Cardio-Thoracic Surgery (EACTS) and the World Heart Federation (WHF). The guiding principle was advocacy for sustainable cardiac surgical capacity in low-income countries. As a first step, a global needs assessment confirmed rheumatic heart disease as the overwhelming pathology requiring cardiac surgery in these regions. Subsequently, CSIA published a request for proposals to support fledgling programmes that could demonstrate the backing by their governments and health care institution. Out of 11 applicants, and following an evaluation of the sites, including site visits to the 3 finalists, Mozambique and Rwanda were selected as the first Pilot Sites. Subsequently, a mentorship and training agreement was completed between Mozambique and the University of Cape Town, a middle-income country with a comparable burden of rheumatic heart disease. The agreement entails regular video calls between the heart teams, targeted training across all aspects of cardiac surgery, as well as on-site presence of mentoring teams for complex cases with the strict observance of 'assisting only'. In Rwanda, Team Heart, a US and Rwanda-based non-governmental organization (NGO) that has been performing cardiac surgery in Rwanda and helping to train the cardiac surgery workforce since 2008, has agreed to continue providing mentorship for the local team and to assist in the establishment of independent cardiac surgery with all that entails. This involves intermittent virtual conferences between Rwandan and US cardiologists for surgical case selection. Five years after CSIA was founded, its 'Seal of Approval' for the sustainability of endorsed programmes in Mozambique and Rwanda has resulted in higher case numbers, a stronger government commitment, significant upgrades of infrastructure, the nurturing of generous consumable donations by industry and the commencement of negotiations with global donors for major grants. Extending the CSIA Seal to additional deserving programmes could further align the international cardiac surgical community with the principle of local cardiac surgery capacity-building in developing countries.

Making a difference: 5 years of Cardiac Surgery Intersociety Alliance (CSIA).

Informed by the almost unimaginable unmet need for cardiac surgery in the developing regions of the world, leading surgeons, cardiologists, editors in chief of the major cardiothoracic journals as well as representatives of medical industry and government convened in December 2017 to address this unacceptable disparity in access to care. The ensuing "Cape Town Declaration" constituted a clarion call to cardiac surgical societies to jointly advocate the strengthening of sustainable, local cardiac surgical capacity in the developing world. The Cardiac Surgery Intersociety Alliance (CSIA) was thus created, comprising The Society of Thoracic Surgeons (STS), the American Association for Thoracic Surgery (AATS), the Asian Society for Cardiovascular and Thoracic Surgery (ASCVTS), the European Association for Cardio-Thoracic Surgery (EACTS) and the World Heart Federation (WHF). The guiding principle was advocacy for sustainable cardiac surgical capacity in low-income countries.

Bronchogenic carcinoma complicating lung transplantation.

BACKGROUND: Malignancy is a well-recognized complication of solid-organ transplantation. Although a variety of malignancies have been reported in lung transplant recipients, a paucity of information exists regarding the incidence and clinical course of bronchogenic carcinoma in this patient population. METHODS: We conducted a retrospective cohort study of our lung transplant experience at the University of Pennsylvania. RESULTS: We identified 6 patients with bronchogenic carcinoma detected at the time of, or developing after, transplantation. The incidence of bronchogenic carcinoma was 2.4%. All patients with lung cancer had a history of smoking, with an average of 79 +/- 39 pack-years. A total of 5 patients had chronic obstructive pulmonary disease, and 1 had idiopathic pulmonary fibrosis. Lung cancers were all of non-small-cell histology and first developed in native lungs. Three patients had bronchogenic carcinoma at the time of surgery. The remaining 3 patients were diagnosed between 280 and 1,982 days post-transplantation. Of the 6 patients, 4 presented with a rapid course suggestive of an infectious process. The 1- and 2-year survival rates after diagnosis were 33% and 17%, respectively. CONCLUSION: Lung transplant recipients are at risk for harboring or developing bronchogenic carcinoma in their native lungs. Rapid progression to locally advanced or metastatic disease commonly occurs, at times mimicking an infection. Bronchogenic carcinoma should be considered in the differential diagnosis of pleuroparenchymal processes involving the native lung.

Characteristics and outcomes of patients with sarcoidosis listed for lung transplantation.

STUDY OBJECTIVES: To characterize the course of patients with advanced sarcoidosis who have been listed for lung transplantation and to identify prognostic factors for death while they are on the waiting list. DESIGN: Retrospective cohort study. SETTING: Tertiary-care university hospital. PATIENTS: Forty-three patients with sarcoidosis who have been listed for lung transplantation at the University of Pennsylvania Medical Center. METHODS: A multivariable explanatory analysis using a Cox proportional hazards model was performed to determine risk factors that are independently associated with mortality while patients await transplantation. RESULTS: Twenty-three of the 43 patients (53%) died while awaiting transplantation. The survival rate of listed patients (as determined by the Kaplan-Meier method) was 66% at 1 year, 40% at 2 years, and 31% at 3 years. In a univariate analysis, the following factors were significantly associated with death on the waiting list: PaO(2) < or = 60 mm Hg (relative risk [RR], 3.4; 95% confidence interval [CI], 1.2 to 9.3); mean pulmonary artery pressure > or = 35 mm Hg (RR, 3.2; 95% CI, 1.1 to 9.5); cardiac index < or = 2 L/min/m(2) (RR, 2.8; 95% CI, 1.2 to 6.6), and right atrial pressure (RAP) > or = 15 mm Hg (RR, 7.6; 95% CI, 3.0 to 19.3). Multivariable analysis revealed that RAP > or = 15 mm Hg was the only independent prognostic variable (RR, 5.2; 95% CI, 1.6 to 16.7; p = 0.006). Twelve patients underwent lung transplantation. Survival after transplantation determined by the Kaplan-Meier method was 62% at both 1 and 2 years, and 50% at 3 years. CONCLUSIONS: Patients with advanced sarcoidosis awaiting lung transplantation have a high mortality rate with a median survival of < 2 years. Mortality is most closely linked to elevated RAP. While earlier referral may diminish the mortality rate of patients on the waiting list for transplantation, further improvements in posttransplantation outcomes will be necessary to ensure that this procedure truly bestows a survival benefit.

New paradigms and improved results for the surgical treatment of acute type A dissection.

OBJECTIVE: To examine the effect of an integrated surgical approach to the treatment of acute type A dissections. SUMMARY BACKGROUND DATA: Acute type A dissection requires surgery to prevent death from proximal aortic rupture or malperfusion. Most series of the past decade have reported a death rate in the range of 15% to 30%. METHODS: From January 1994 to March 2001, 104 consecutive patients underwent repair of acute type A dissection. All had an integrated operative management as follows: intraoperative transesophageal echocardiography; hypothermic circulatory arrest (HCA) with retrograde cerebral perfusion (RCP) to replace the aortic arch; HCA established after 5 minutes of electroencephalographic (EEG) silence in neuromonitored patients (66%) or after 45 minutes of cooling in patients who were not neuromonitored (34%); reinforcement of the residual arch tissue with a Teflon felt "neo-media"; cannulation of the arch graft to reestablish cardiopulmonary bypass at the completion of HCA (antegrade graft perfusion); and remodeling of the sinus of Valsalva segments with Teflon felt "neo-media" and aortic valve resuspension (78%) or replacement with a biologic or mechanical valved conduit (22%). RESULTS: Mean age was 59 +/- 15 (range 22-86) years, with 71% men and 13% redo sternotomy after a previous cardiac procedure. Mean cardiopulmonary bypass time was 196 +/- 50 minutes. Mean HCA with RCP time was 42 +/- 12 minutes (range 19-84). Mean cardiac ischemic time was 140 +/- 45 minutes. Eleven percent of patients presented with a preoperative neurologic deficit, and 5% developed a new cerebrovascular accident after dissection repair. The in-hospital death rate was 9%. Excluding the patients who presented neurologically unresponsive or with ongoing cardiopulmonary resuscitation (n = 5), the death rate was 4%. In six patients adverse cerebral outcomes were potentially avoided when immediate surgical fenestration was prompted by a sudden change in the EEG during cooling. Forty-five percent of neuromonitored patients required greater than 30 minutes to achieve EEG silence. CONCLUSION: The authors have shown that the surgical integration of sinus segment repair or aortic root replacement, the use of EEG monitoring, partial or total arch replacement using RCP, routine antegrade graft perfusion, and the uniform use of transesophageal echocardiography substantially decrease the death and complication rates of acute type A dissection repair.

Deep hypothermic circulatory arrest: I. Effects of cooling on electroencephalogram and evoked potentials.

BACKGROUND: Deep hypothermia is an important cerebral protectant and is critical in procedures requiring circulatory arrest. The purpose of this study was to determine the factors that influence the neurophysiologic changes during cooling before circulatory arrest, in particular the occurrence of electrocerebral silence. METHODS: In 109 patients undergoing hypothermic circulatory arrest with neurophysiologic monitoring, five electrophysiologic events were selected for detailed study. RESULTS: The mean nasopharyngeal temperature when periodic complexes appeared in the electroencephalogram after cooling was 29.6 degrees C +/- 3 degrees C, electroencephalogram burst-suppression appeared at 24.4 degrees C +/- 4 degrees C, and electrocerebral silence appeared at 17.8 degrees C +/- 4 degrees C. The N20-P22 complex of the somatosensory evoked response disappeared at 21.4 degrees C +/- 4 degrees C, and the somatosensory evoked response N13 wave disappeared at 17.3 degrees C +/- 4 degrees C. The temperatures of these various events were not significantly affected by any patient-specific or surgical variables, although the time to cool to electrocerebral silence was prolonged by high hemoglobin concentrations, low arterial partial pressure of carbon dioxide, and by slow cooling rates. Only 60% of patients demonstrated electrocerebral silence by either a nasopharyngeal temperature of 18 degrees C or a cooling time of 30 minutes. CONCLUSIONS: With the high degree of interpatient variability in these neurophysiologic measures, the only absolute predictors of electrocerebral silence were nasopharyngeal temperature below 12.5 degrees C and cooling longer than 50 minutes.

Deep hypothermic circulatory arrest: II. Changes in electroencephalogram and evoked potentials during rewarming.

BACKGROUND: Electrophysiologic studies during rewarming after deep hypothermic circulatory arrest probe the state of the brain during this critical period and may provide insight into the neurological effects of circulatory arrest and the neurologic outcome. METHODS: Electroencephalogram (EEG) and evoked potentials were monitored during rewarming in 109 patients undergoing aortic surgery with hypothermic circulatory arrest. RESULTS: The sequence of neurophysiologic events during rewarming did not mirror the events during cooling. The evoked potentials recovered first followed by EEG burst-suppression and then continuous EEG. The time to recovery of the evoked potentials N20-P22 complex was significantly correlated with the time of circulatory arrest even in patients without postoperative neurologic deficits (r = 0.37, (p = 0.002). The nasopharyngeal temperatures at which continuous EEG activity and the N20-P22 complex returned were strongly correlated (r = 0.44, p = 0.0002; r = 0.41, p = 0.00003) with postoperative neurologic impairment. Specifically, the relative risk for postoperative neurologic impairment increased by a factor of 1.56 (95% CI 1.1 to 2.2) for every degree increase in temperature at which the EEG first became continuous. CONCLUSIONS: No trend toward shortened recovery times or improved neurologic outcome was noted with lower temperatures at circulatory arrest, indicating that the process of cooling to electrocerebral silence produced a relatively uniform degree of cerebral protection, independent of the actual nasopharyngeal temperature.

Structural determinants of aortic regurgitation in type A dissection and the role of valvular resuspension as determined by intraoperative transesophageal echocardiography.

Disruption of the aortic root by dissection often produces significant aortic regurgitation (AR). Resuspension of the native valve usually reestablishes competence. The mechanisms of this complex process are poorly understood. We used intraoperative transesophageal echocardiography to characterize the in vivo aortic root structure of type A aortic dissection and the changes brought about by native valve resuspension. Intraoperative transesophageal echocardiograms were obtained from 34 patients with type A dissection and aortic resuspension between January 1990 and April 1997. The severity of AR, aortic root diameter, circumference of the aortic annulus, percentage of the annulus dissected, and presence of leaflet prolapse were assessed in multiple planes. Preoperatively, AR of varying degree was present in 25 patients (73%). Multivariate analysis revealed that preoperative AR was most related to percentage of the annulus dissected (p<0.0001) and less related to root diameter (p<0.01). Leaflet prolapse was predicted by percent aortic annulus dissected (p <0.0001). After resuspension, annular dissection and leaflet prolapse were no longer present. Postoperative AR was significantly decreased from preoperative AR (p<0.0001) and was considered trace to mild. Although postoperative root diameter and annular circumference decreased (p<0.001), individual reductions in AR did not correlate with individual changes in root diameter or annular circumference. The degree of dissection of the valve annulus is the most significant determinant of leaflet prolapse and AR severity. Overall size of the aortic root also contributes to AR. Surgical resuspension significantly decreases root size, but its primary benefit is restoration of the structural integrity of the aortic annulus.

Bicuspid aortic valves are associated with aortic dilatation out of proportion to coexistent valvular lesions.

BACKGROUND: Bicuspid aortic valves (BAVs) are associated with premature valve stenosis, regurgitation, and ascending aortic aneurysms. We compared aortic size in BAV patients with aortic size in control patients with matched valvular lesions (aortic regurgitation, aortic stenosis, or mixed lesions) to determine whether intrinsic aortic abnormalities in BAVs account for aortic dilatation beyond that caused by valvular hemodynamic derangement alone. METHODS AND RESULTS: Diameters of the left ventricular outflow tract, sinus of Valsalva, sinotubular junction, and proximal aorta were measured from transthoracic echocardiograms in 118 consecutive BAV patients. Annular area was measured by planimetry, and BAV eccentricity was expressed as the ratio of the right leaflet area to the total annular area. Seventy-seven control patients with tricuspid aortic valves were matched for sex and for combined severity of regurgitation and stenosis. BAV patients (79 men and 39 women, aged 44.1+/-15.5 years) had varying degrees of regurgitation (84 patients [71%]) and stenosis (48 patients [41%]). Within the bicuspid group, multivariate analysis demonstrated that aortic diameters increased with worsening aortic regurgitation (P:<0.001) and advancing age (P:<0.05) but not with the severity of aortic stenosis. BAV patients had larger aortic diameters than did control patients at all ascending aortic levels measured (P:<0.01), despite advanced age in the control patients. CONCLUSIONS: Aortic dimensions are larger in BAV patients than in control patients with comparable degrees of tricuspid aortic valve disease. Although more severe degrees of aortic regurgitation are associated with aortic dilatation in BAV patients, intrinsic pathology appears to be responsible for aortic enlargement beyond that predicted by hemodynamic factors.

Comparison of clinical results for unilateral and bilateral thoracoscopic lung volume reduction.

BACKGROUND: It is widely believed that bilateral thoracoscopic lung volume reduction (BTLVR) yields superior results when compared with unilateral thoracoscopic lung volume reduction (UTLVR) with regard to spirometry, functional capacity, oxygenation and quality of life results. METHODS: To address these issues, we compared the results of patients undergoing UTLVR (N = 338 patients) and BTLVR (N = 344 patients) from 1993 to 1998 at five institutions. Follow-up data were available on 671 patients (98.4%) between 6 and 12 months after surgery, and a patient self-assessment was obtained at a mean of 24 months. RESULTS: It was found that BTLVR provides superior improvement in measured postoperative percent change in FEV1 (L) (UTLVR 23.3% +/- 55.3 vs BTLVR 33% +/- 41, p = 0.04), FVC(L) (10.5% +/- 31.6 vs 20.3% +/- 34.3, p = 0.002) and RV(L) (-13% +/- -22 vs -22% +/- 17.9, p = 0.015). BTLVR also provides a slight improvement over UTLVR in patient's perception regarding improved quality of life (UTLVR 79% vs BTLVR 88%, p = 0.03) and dyspnea relief (71% vs 61%, p = 0.03). There was no difference in mean changes in PO2 (mm Hg) (UTLV 4.5 +/- 12.3 vs BTLVR 4.9 +/- 13.3, p = NS), 6-minute walk (UTLVR 26% +/- 66.1 vs BTLVR 31% +/- 59.6, p = NS) or decreased oxygen utilization (UTLVR 78% vs BTLVR 74%, p = NS). CONCLUSIONS: These data suggest that both UTLVR and BTLVR yield significant improvement, but the results of BTLVR seem to be superior with regard to spirometry, lung volumes, and quality of life.

Acute type A aortic dissection: retrograde perfusion with left superior vena cava.

Retrograde cerebral perfusion with hypothermic circulatory arrest confers additional cerebral protection during repair of type A aortic dissection. We present a 42-year-old man with acute type A aortic dissection and a persistent, left superior vena cava. Cannulation of the right and left superior vena cava is used for retrograde perfusion of both hemispheres with bilateral monitoring of electroencephalogram and somatosensory-evoked potentials during and after the hypothermic circulatory arrest interval.

Risk analysis for thoracoscopic lung volume reduction: a multi-institutional experience.

OBJECTIVE: Most reports of thoracoscopic lung volume reduction (TLVR) are relatively small and early experiences from a single institution, factors which limit both the statistical validity and the applicability to the population at large. In order to address these shortcomings we undertook an analysis of the TLVR experience at five separate institutions to assess operative morbidity and identify predictors of mortality. METHODS: Questionnaires were sent to four groups of surgical investigators at five institutions actively performing TLVR. Data was requested regarding preoperative, operative and postoperative parameters. Twenty-five potential predictors of mortality were analyzed and seven proved to be at least marginally significant (P<0.10). These parameters were entered into a stepwise logistic regression analysis to identify independent predictors. RESULTS: The 682 patients (415 males, 267 females, mean age 64.0 years) underwent unilateral (410) or bilateral (272) TLVRs. Overall, operative mortality was 6% with half of the deaths resulting from respiratory causes. The remaining patients were discharged to home (88%), a rehabilitation facility (4%) or a ventilator facility (2%). There were 25 perioperative factors chosen representing clinically important indices such as spirometry, oxygenation, functional status, clinical and demographic variables. Univariate analysis identified seven variables as predictors of mortality (P<0.10) and these were entered into a stepwise logistic regression analysis. Only age, 6-min walk, gender (male 8%, female 3% mortality) and the procedure performed (unilateral 4.6%, bilateral 8%) were independent predictors while preoperative steroid therapy, preoperative oxygen administration, and time since smoking cessation dropped out of the model. The specific institution, learning curve (early vs. late experience), type of lung disease, spirometric indices and predicted maximum VO(2) were not significant predictors. CONCLUSION: This experience suggests that unilateral and bilateral lung volume reduction procedure can be performed with acceptable morbidity and mortality. Although age, gender, exercise capacity and the procedure performed are all independent predictors of mortality, the risk of operative death did not appear excessive in this fragile patient subset.

Fatal hyperammonemia after orthotopic lung transplantation.

BACKGROUND: A case of fatal hyperammonemia complicating orthotopic lung transplantation was previously reported. OBJECTIVE: To describe the incidence, clinical features, and treatment of hyperammonemia associated with orthotopic lung transplantation. DESIGN: Retrospective cohort analysis. SETTING: Academic medical center and lung transplantation center in Philadelphia, Pennsylvania. PATIENTS: 145 sequential adult patients who underwent orthotopic lung transplantation. MEASUREMENTS: Plasma ammonium levels. RESULTS: Six of the 145 patients who had had orthotopic lung transplantation developed hyperammonemia, all within the first 26 days after transplantation. The 30-day post-transplantation mortality rate was 67% for patients with hyperammonemia compared with 17% for those without hyperammonemia (P = 0.01). Development of major gastrointestinal complications (P = 0.03), use of total parenteral nutrition (P < 0.001), and lung transplantation for primary pulmonary hypertension (P = 0.045) were associated with hyperammonemia. CONCLUSIONS: Hyperammonemia is a potentially fatal event occurring after orthotopic lung transplantation. It is associated with high nitrogen load, concurrent medical stressors, primary pulmonary hypertension, and hepatic glutamine synthetase deficiency.

Bilateral versus single lung transplantation for chronic obstructive pulmonary disease: intermediate-term results.

BACKGROUND: There is controversy regarding the transplant procedure of choice in chronic obstructive pulmonary disease. We reviewed our intermediate-term outcomes with single lung transplantation (SLT) versus bilateral lung transplantation (BLT). METHODS: We retrospectively reviewed 130 patients with chronic obstructive pulmonary disease: 84 underwent SLT, 46 BLT. The mean age was 51.1 +/- 1.2 years for those who underwent BLT and 56.2 +/- 0.7 years for those who underwent SLT (p < 0.0001). Male patients represented 65% of the BLT group and 46% of the SLT group (p = 0.04). Spirometry and 6-minute walk tests were obtained preoperatively and at 3- to 6-month intervals. Posttransplant survival and survival from time of onset of bronchiolitis obliterans syndrome were calculated by Kaplan-Meier method. The mean follow-up was 32.4 months. RESULTS: The 90-day mortality rate was 13.0% For BLT and 15.5% for SLT (p = 0.71). Actuarial survival rates at 1, 3, and 5 years were 82.6%, 74.6%, and 61.9% for BLT and 72.2%, 63.4%, and 57.4% for SLT; the favorable survival trend with BLT did not achieve statistical significance. There were no differences in preoperative spirometry or 6-minute walk tests. The improvements in forced expiratory volume in one second, forced vital capacity (FVC), and 6 MWT were significantly greater following BLT. The incidence of bronchiolitis obliterans syndrome was 22.4% in SLT and 22.2% in BLT; survival following onset of bronchiolitis obliterans syndrome was similar. CONCLUSIONS: For patients with chronic obstructive pulmonary disease, BLT is associated with superior lung function, exercise tolerance, and a trend toward enhanced survival. Younger candidates may be best suited for BLT. Given the limited donor lungs, SLT remains the preferred alternative for all other patients.