Lung transplantation with bronchial revascularisation. Surgical anatomy, operative technique and early results

History of Lung Transplantation

Lung transplantation remains the only available therapy for many patients with end-stage lung disease. The number of lung transplants performed has increased significantly, but development of the field was slow compared with other solid-organ transplants. This delayed growth was secondary to the increased complexity of transplanting lungs; the continuous needs for surgical, anesthetics, and critical care improvements; changes in immunosuppression and infection prophylaxis; and donor management and patient selection. The future of lung transplant remains promising: expansion of donor after cardiac death donors, improved outcomes, new immunosuppressants targeted to cellular and antibody-mediated rejection, and use of xenotransplantation or artificial lungs.

Is there life on the airway tree? A pilot study of bronchial cell vitality and tissue morphology in the ex vivo lung perfusion (EVLP) era of lung transplantation

BACKGROUND

Ex vivo lung perfusion (EVLP) is a relevant procedure to increase the lung donor pool but could potentially increase the airway tree ischemic injury risk.

METHODS

This study aimed to evaluate the direct effect of EVLP on the airway tree by evaluating bronchial cell vitality and tissue signs of injury on a series of 117 bronchial rings collected from 40 conventional and 19 EVLP-treated lung grafts. Bronchial rings and related scraped bronchial epithelial cells were collected before the EVLP procedure and surgical anastomosis.

RESULTS

The preimplantation interval was significantly increased in the EVLP graft group (p < 0.01). Conventional grafts presented cell viability percentages of 47.07 ± 23.41 and 49.65 ± 21.25 in the first and second grafts which did not differ significantly from the EVLP group (first graft 50.54 ± 25.83 and second graft 50.22 ± 20.90 cell viability percentage). No significant differences in terms of histopathological features (edema, inflammatory infiltrate, and mucosa ulceration) were observed comparing conventional and EVLP samples. A comparison of bronchial cell viability and histopathology of EVLP samples retrieved at different time intervals revealed no significant differences. Accordingly, major bronchial complications after lung transplant were not observed in both groups.

CONCLUSIONS

Based on these data, we observed that EVLP did not significantly impact bronchial cell vitality and airway tissue preservation nor interfere with bronchial anastomosis healing, further supporting it as a safe and useful procedure.

Lung transplant with bronchial arterial revascularization: review of surgical technique and clinical outcomes

Lung transplantation (LTx) is routinely performed with sacrifice of the bronchial arterial circulation. We review bronchial artery anatomy and surgical technique for LTx with direct bronchial arterial revascularization (BAR). We also update the published clinical experience, including from our center, of LTx with BAR. Published series of LTx with BAR are from single centers, and all cite high technical success rates and good short-term outcomes. Technically, double LTx (DLTx) with BAR is almost always possible if a deliberate review of bronchial artery anatomy is performed. For single LTx (SLTx), BAR is feasible in about 50% of cases. The combined Copenhagen and Cleveland Clinic experience (with BAR procedures performed or supervised by Dr. Gosta B. Pettersson) includes 131 LTx with BAR with a technical success rate >95%. Procedural success is uniformly associated with normal airway healing. Five-year survival in LTx with BAR is superior to the 5-year survival of LTx patients in the ISHLT registry. LTx with BAR is feasible and safe, and technical success ensures normal airway healing. The experience with BAR at experienced centers suggests possible long-term survival benefit. A multicenter study is needed to define the role of BAR in LTx.

Pathophysiology and Predictors of Bronchial Complications After Lung Transplantation

Bronchial anastomotic breakdown was a major complication in the early days of lung transplantation. Their solution, achieved through an understanding of airway ischemia from the laboratory, was key to the initial clinical success. Subsequently, risk factors, such as prolonged ventilation in both donor and recipient, primary graft dysfunction, and recipient age, have emerged. Innovations, such as local tissue wrapping, telescoping the anastomosis, and bronchial artery revascularization, have not stood the test of time. The short donor bronchus, with a suture line at the level of the lobar bronchus carina, is a proven technique that should be adopted by surgeons.

ISHLT Consensus Statement on adult and pediatric airway complications after lung transplantation: Definitions, grading system, and therapeutics

Airway complications remain a major cause of morbidity and mortality after cardiothoracic transplantation. The reported incidence of airway ischemic complications varies widely, contributed to by the lack of a universally accepted grading system and standardized definitions. Furthermore, the majority of the existing classification systems fail to integrate the wide range of possible bronchial complications that may develop after lung transplant. Hence, a Working Group was created by the International Society for Heart and Lung Transplantation with the aim of elaborating a universal definition of adult and pediatric airway complications and grading system. One such area of focus is to understand the problem in the context of a more standardized consensus of classifying airway ischemia. This consensus definition will have major clinical, therapeutics, and research implications.

History of lung transplantation

Lung transplantation nowadays is a well-accepted and routine treatment for well selected patients with terminal respiratory disease. However, it took several decades of experimental studies and clinical attempts to reach this success. In this paper, we describe the early experimental activity from the mid-forties until the early sixties. The first clinical attempt in humans was reported by Hardy and Webb in 1963 followed by others with short survival only except for one case by Derom et al. who lived for 10 months. Long-term successes were not reported until after the discovery of cyclosporine as a new immunosuppressive agent. Successful heart-lung transplantation (HLTx) for pulmonary vascular disease was performed by the Stanford group starting in 1981 while the Toronto group described good outcome after single-lung transplantation (SLTx) for pulmonary fibrosis in 1983 and after double-lung transplantation for emphysema in 1986. Further evolution in surgical techniques and in transplant type for the various forms of end-stage lung diseases are reviewed. The evolution in lung transplantation still continues nowadays with the use of pulmonary allografts coming from living-related donors, from donors after circulatory death, or after prior assessment and reconditioning during ex vivo lung perfusion (EVLP) in an attempt to overcome the critical shortage of suitable organs. Early outcome has significantly improved over the last three decades. Better treatment and prevention of chronic lung allograft dysfunction will hopefully result in further improvement of long-term survival after lung transplantation.

Airway complications after lung transplantation

Airway complications after lung transplantation present a formidable challenge to the lung transplant team, ranging from mere unusual images to fatal events. The exact incidence of complications is wide-ranging depending on the type of event, and there is still evolution of a universal characterization of the airway findings. Management is also wide-ranging. Simple observation or simple balloon bronchoplasty is sufficient in many cases, but vigilance following more severe necrosis is required for late development of both anastomotic and nonanastomotic airway strictures. Furthermore, the impact of coexisting infection, rejection, and medical disease associated with high-level immunosuppression further complicates care.

The role of bronchial artery revascularization in lung transplantation

Long-term survival of lung-transplant patients is 53% at 5 years and 31% at 10 years, lagging behind the survival of other solid organs recipients. Modern lung transplantation has seen a shift from early mortality and complications related to the bronchial anastomosis to late mortality secondary to progressive organ dysfunction; the complex disease process may include elements of bronchiolitis obliterans syndrome, obliterative bronchiolitis, chronic rejection, or chronic lung allograft dysfunction. Initial goals of bronchial artery revascularization include reducing the incidence of airway ischemia and improving bronchial healing. Benefits of restored bronchial artery circulation may extend beyond bronchial healing alone.

A novel dual ex vivo lung perfusion technique improves immediate outcomes in an experimental model of lung transplantation

The lungs are dually perfused by the pulmonary artery and the bronchial arteries. This study aimed to test the feasibility of dual-perfusion techniques with the bronchial artery circulation and pulmonary artery circulation synchronously perfused using ex vivo lung perfusion (EVLP) and evaluate the effects of dual-perfusion on posttransplant lung graft function. Using rat heart-lung blocks, we developed a dual-perfusion EVLP circuit (dual-EVLP), and compared cellular metabolism, expression of inflammatory mediators, and posttransplant graft function in lung allografts maintained with dual-EVLP, standard-EVLP, or cold static preservation. The microvasculature in lung grafts after transplant was objectively evaluated using microcomputed tomography angiography. Lung grafts subjected to dual-EVLP exhibited significantly better lung graft function with reduced proinflammatory profiles and more mitochondrial biogenesis, leading to better posttransplant function and compliance, as compared with standard-EVLP or static cold preservation. Interestingly, lung grafts maintained on dual-EVLP exhibited remarkably increased microvasculature and perfusion as compared with lungs maintained on standard-EVLP. Our results suggest that lung grafts can be perfused and preserved using dual-perfusion EVLP techniques that contribute to better graft function by reducing proinflammatory profiles and activating mitochondrial respiration. Dual-EVLP also yields better posttransplant graft function through increased microvasculature and better perfusion of the lung grafts after transplantation.

Comparative study of bronchial artery revascularization in lung transplantation

OBJECTIVE

Restoring dual blood supply to transplanted lungs by bronchial artery revascularization (BAR) remains controversial. We compared outcomes after lung transplantation performed with and without BAR.

METHODS

From December 2007 to July 2010, 283 patients underwent transplantation; 187 were 18 years or older, without previous or concomitant cardiac surgery. Of these patients, 27 underwent BAR in a pilot study to test success, safety, effectiveness, and teachability. A propensity score was generated to match BAR patients and 54 routine non-BAR patients. Follow-up was 1.3 ± 0.68 years.

RESULTS

BAR was angiographically successful in 26 (96%) of 27 patients. BAR and non-BAR patients had similar skin-to-skin time (P = .07) and postoperative hospital stays (P = .2), but more reoperations for bleeding (P = .002). Tracheostomy was performed in 9 (33%) of 27 BAR and 10 (19%) of 54 non-BAR patients (P = .2, log-rank). One BAR (3.7%) and 4 non-BAR (7.4%) patients required extracorporeal membrane oxygenation (P = .7). Airway ischemia was observed in 1 BAR (3.7%) versus 12 non-BAR (22%) patients (P = .03); anastomotic intervention was required in no BAR versus 8 non-BAR (15%) patients (P = .04). Hospital mortality was 1 of 27 versus 2 of 54 (P = .9). BAR patients had lower early biopsy tissue rejection grades (P = .008) and fewer pulmonary (P < .04) and bloodstream (P < .02) infections. Forced 1-second expiratory volume was similar (P > .2); 3 BAR versus 9 non-BAR patients developed bronchiolitis obliterans syndrome (BOS) (P = .14, log-rank). During follow-up, 4 BAR and 8 non-BAR patients died (P = .6, log-rank).

CONCLUSIONS

BAR is safe, with comparable early outcomes. Benefits of BAR include reduced airway ischemia and complications, lower biopsy tissue grades, fewer infections, and delay of BOS. A multicenter study is needed to establish these benefits.

Lung transplant

The ICU period is only one time point among many in the complex, multidisciplinary postoperative management required for patient survival and improved QOL. The care required on step-down units and after discharge to home each has unique care aspects that impact successful patient outcomes.

Interventional techniques in the management of airway complications following lung transplantation

The last four decades have seen tremendous advances in the field of pulmonary transplantation. Vast improvements in the areas of surgical transplantation techniques, immunosuppressive agents, and postoperative care have all contributed to improved survival of patients. Advances in noninvasive imaging and bronchoscopy have allowed the pulmonary transplant team to intervene early in patients presenting with airway complications, often using minimally invasive procedures such as endobronchial balloon dilation or stent placement, or both. Stent technology itself has also improved and stents may sometimes be customized for treatment of short airway lesions or to optimize continued airflow through the sides of stents by creating openings using balloons or bronchoscopically directed laser. Preliminary work with brachytherapy may be decreasing the need for secondary reinterventions. The authors present an overview of some of these conventional and novel approaches to the treatment of airway complications after lung transplantation.

Healing of bronchial allografts in pigs

Our purpose was to investigate the healing of bronchial grafts in a porcine experimental model. Via left thoracotomy, a 2.5 cm long bronchial stump was anastomosed back to the same animal (autograft) or to another pig (allograft). Autotransplanted bronchi (six pigs) healed very well without infection. Allotransplantation without immunosuppression (eight pigs) was followed in all cases by rejection with formation of major bronchopleural fistula. After allotransplantation with triple-drug immunosuppressive medication (seven pigs), three pigs showed infection-free healing, but the anastomoses were slightly stenosed at the time of sacrifice (mean 30 d), while four had bronchopleural fistula. The study thus showed the healing ability of totally avascular bronchial graft in pigs to be very good when it is autotransplanted, but poor when allotransplanted without immunosuppressive treatment.

Magnetic resonance imaging angiography in patency evaluation of bronchial artery revascularization grafts

In this report we present our experience of non-invasive magnetic resonance imaging (MR) angiography and selective catheter angiography in assessing the patency of bronchial artery revascularization grafts after an en bloc double-lung and heart-lung transplantation. We studied 8 patients who had undergone pulmonary transplantation with direct bronchial artery revascularization. Catheter angiography was performed 10 days to 63 months postoperatively. MR angiography was performed within 24 h of the catheter procedure and the results were compared with the findings from catheter angiography. Catheter angiography showed the bronchial revascularization graft to be patent in 6 patients and occluded in 2. At MR angiography, the patency of bronchial artery revascularization grafts was reliably identified in 7 of the 8 patients. One patient had inadequate image quality because of void artefacts caused by haemostatic clips. It is concluded that MR angiography is a reliable method for assessing the patency of bronchial artery revascularization grafts.

Refractory post-transplant airway strictures: successful management with wire stents

OBJECTIVE

Bronchial stenosis, malacia and dehiscence are major airway complications of lung transplantation. Our success in managing this problem evolved from the use of semi-rigid dilators, to balloon dilation and placement of a stent, which were initially silicone, thereafter wire balloon-expandable and finally wire self-expandable.

METHODS

From May, 1994 until July 1997, we performed a total of 49 single and 58 bilateral lung transplants. Symptoms of shortness of breath, verified by a drop in the forced expiratory volume in one second (FEV1), led to bronchoscopic inspection of the airway in lung transplant patients. Eighteen patients (16%) suffered a severe form of airway complication (dehiscence or stenosis) in 24 of 151 airways at risk (15.9%). These anastomotic strictures were recalcitrant to conventional therapy. Intervention consisted of rigid bronchoscopy, dilation of the stricture and placement of a stent. Flexible bronchoscopy and fluoroscopy were used for precise placement of the stent. As the initial stent, the Hood silicone stent was placed five times in four patients and the Dumont studded stent five times in four patients. The Palmaz wire stent was used as the initial stent 10 times in seven patients and the Wallstent used eight times in seven patients. Four patients had multiple stents. Balloon inflation moulded the wire stent to the airway.

RESULTS

There was no mortality resulting from the airway complication or any intervention. The most serious complication was a perforation of the airway using the semi-rigid dilator that necessitated immediate thoracotomy and re-anastomosis of the bronchus. Other complications necessitated repeat interventions due to restenosis or failure of the stents. The success of the stent placement was measured subjectively by the immediate ease of breathing enjoyed by each patient and objectively by the significant increase of the FEV1 from a pre-operative mean of 1.19 l (SD 0.64 l) to a post-operative mean of 2.06 l (SD 0.70 l) (P < 0001). The mean number of interventions according to the type of wire stent first used was significantly fewer with Wallstent insertion (1.28 (SD 0.48)) than in those patients in whom a Palmaz stent was inserted (5.22 (SD 2.38)) (P < 0008).

CONCLUSION

The airway complication of stricture, broncho-malacia or dehiscence following lung transplantation can be managed effectively and easily with the use of balloon catheter dilation followed by precise placement of a self-expandable wire stent. The Wallstent is the superior stent for this application.

Airway epithelium of transplanted lungs with and without direct bronchial artery revascularization

OBJECTIVE

Normal systemic blood flow to the airways and lung parenchyma of transplanted lungs can only be re-established by direct bronchial artery revascularization. The purpose of the present study was to investigate whether such direct bronchial artery revascularization would preserve ciliary function, previously shown to be reduced in lungs transplanted without revascularization.

METHODS

Twenty-five single lung transplanted patients were included in this study. Complete direct bronchial artery revascularization was achieved in eight patients. In 16 patients the procedure had either failed (n = 10) or was not attempted (n = 6). In one patient the result of the revascularization was unknown. Airway epithelium samples were obtained from the native and the transplanted lungs during bronchoscopic examinations. Airway erythema and excessive secretion were registered. The epithelium samples underwent histological examination and ciliary beat frequency was measured in vitro by video recording. Transbronchial biopsies from the transplanted lungs were examined for signs of rejection and bronchitis.

RESULTS

No differences in ciliary beat frequency nor in the distribution of ciliated/de-ciliated columnar epithelium cells between native lungs and transplanted lungs with or without successful direct bronchial artery revascularization could be demonstrated. In 38% of the transplanted lungs without successful revascularization metaplastic or squamous epithelium was present, while lungs with successful revascularization had only normal columnar epithelium. Ongoing rejection or airway erythema did not influence ciliary beat frequency. Excessive secretion in the airways was the only finding associated with significantly increased ciliary beat frequency.

CONCLUSIONS

Ciliary beat frequency of epithelium cells of transplanted lungs did not differ from that of native lungs and consequently direct bronchial artery revascularization did not have any demonstrable important influence. Excessive secretion in the airways was associated with increased ciliary beat frequency. The histological findings also showed that the abundance of ciliated cells was preserved in transplanted bronchi irrespective of bronchial artery revascularization. However, epithelium metaplasia was only seen in transplanted bronchi without revascularization.

Medium-term patency and anatomic changes after direct bronchial artery revascularization in lung and heart-lung transplantation with the internal thoracic artery conduit

OBJECTIVE

Our purpose was to study the 2-year patency of direct bronchial artery revascularization in lung transplantation. We wanted to clarify whether the revascularized bronchial artery system is functional after 2 years, whether bronchial artery vascularity changes with time, and whether posttransplantation bronchial artery disease is arteriographically evident after 2 years.

METHODS

Bronchial artery revascularization is performed by anastomosing the internal thoracic artery to as many bronchial artery orifices in the donor descending aorta as possible. Twenty-three patients surviving 2 years or more have had internal thoracic artery-bronchial arteriography performed 1 month and 2 years after transplantation. One-month and 2-year arteriograms have been compared.

RESULTS

Two-year patency of the internal thoracic artery conduit was 100%. The appearance of the bronchial arteries was unchanged after 2 years in 11 patients. A unilateral or bilateral increase in vascularity was found in two and seven patients, respectively. In three patients new vessels, not visible on the first arteriogram, had appeared. In four patients one or more small vessels visible on the first arteriogram had disappeared on the second arteriogram. We have found no arteriographic signs of bronchial artery disease, such as stenosis of the bronchial arteries, and no arteriographic evidence of arteriosclerotic disease in the internal thoracic artery.

CONCLUSION

The internal thoracic artery is an excellent conduit for bronchial artery revascularization, with a 2-year patency of 100% in 23 patients. Only minor changes in the bronchial arteriograms have been found.

Early and late airway complications after lung transplantation: incidence and management

BACKGROUND

Airway anastomosis complications continue to be a source of morbidity for lung transplant recipients.

METHODS

This study analyzes incidence, treatment, and follow-up of airway anastomotic complications occurring in 127 consecutive lung transplant airway anastomoses (77 single lung and 25 bilateral sequential lung). Complications were categorized as stenosis (11), granulation tissue (8), infection (7), bronchomalacia (5), or dehiscence (3). Follow-up after treatment ranged from 6 months to 4 years.

RESULTS

Nineteen airway anastomosis complications (15.0%) occurred in 18 patients. Telescoping the airway anastomosis reduced the complication rate to 12 of 97 (12.4%), compared with 7 of 30 (23.3%) for omental wrapping, (p = 0.15). Complications developed in 13 of 77 single-lung airway anastomoses (16.9%) versus 6 of 50 bilateral sequential lung recipients (12.0%). Treatment consisted of stenting (9 airway anastomoses), bronchodilation (8), laser debridement (4), rigid bronchoscopic debridement (2), operative revision (2), and growth factor application (2). There was no difference in actuarial survival between patients with or without airway anastomosis complications (p = 1.0).

CONCLUSIONS

Airway anastomosis complications can be successfully managed in the immediate or late postoperative period with good outcome up to 4 years after intervention.

Intermediate-term results after en bloc double-lung transplantation with bronchial arterial revascularization. Bordeaux Lung and Heart-Lung Transplant Group

OBJECTIVE

Between May 1990 and January 1994, 18 patients underwent en bloc double-lung transplantation with tracheal anastomosis and bronchial arterial revascularization. Because at that time it was already suggested that chronic ischemia could be a contributing factor in occurrence of obliterative bronchiolitis, the purpose of this study was to evaluate, with a follow-up ranging from 22 to 69 months, the midterm effects of bronchial arterial revascularization on development of obliterative bronchiolitis.

RESULTS

Results were assessed according to tracheal healing, functional results, rejection, infection, and incidence of obliterative bronchiolitis. There were no intraoperative deaths or reexplorations for bleeding related to bronchial arterial revascularization, but there were three hospital deaths and five late deaths, two of them related to obliterative bronchiolitis. According to the criteria previously defined, tracheal healing was assessed as grade I, IIa, or IIb in 17 patients and grade IIIa in only one patient. Early angiography (postoperative days 20 to 40) demonstrated a patent graft in 11 of the 14 patients in whom follow-up information was obtained. Ten patients are currently alive with a 43-month mean follow-up. Among the 15 patients surviving more than 1 year, functional results have been excellent except in five in whom obliterative bronchiolitis has developed and who had an early or late graft thrombosis. Furthermore, those patients had a significantly higher incidence of late acute rejection (p < 0.02), cytomegalovirus disease (p < 0.006), and bronchitis episodes (p < 0.0008) than patients free from obliterative bronchiolitis.

CONCLUSION

We conclude that besides its immediate beneficial effect on tracheal healing, long-lasting revascularization was, at least in this small series, associated with an absence of obliterative bronchiolitis, thus suggesting but not yet proving the possible role of chronic ischemia in this multifactorial disease.

Revascularization of the bronchial arteries in lung transplantation: an overview

Development of the surgical technique has minimized the incidence of airway problems associated with single as well as sequential bilateral lung transplantation. Although early results are good, long-term results remain unsatisfactory. The main problems after lung transplantation are pulmonary infections and the bronchiolitis obliterans syndrome. The bronchiolitis obliterans syndrome is usually considered to be chronic rejection, but a multifactorial genesis including airway ischemia has been suggested. We reviewed the literature relevant to direct bronchial artery revascularization during lung transplantation. Although information is limited, there are good reasons to believe that reestablishment of the dual blood supply to the transplanted lung is beneficial not only for healing of the airway anastomoses, but also for the airway and the lung responses to pathologic conditions. In small series, methods of bronchial artery revascularization have proved successful and have been associated with good early results. We believe it is justified to test the impact of direct bronchial artery revascularization on outcome after lung transplantation in large clinical series.

Evolving strategies in lung transplantation for emphysema

Evolving strategies of pulmonary preservation, bronchial revascularization, immunosuppression, and infectious disease management were used in 15 initial consecutive patients undergoing lung transplantation for emphysema. There were 10 women and 5 men with a mean age of 49 years (range, 36 to 60 years). All patients required supplemental oxygen therapy. One bilateral, 9 left, and 5 right transplantations were performed. Mean preoperative forced expiratory volume in 1 second and total lung capacity were 16% and 146%, respectively, of predicted. Quadruple drug immunosuppression was used. Actuarial 1-year survival in this initial series is 93.3% +/- 6.4% (Kaplan-Meier) with one early cardiac death at day 71. Mean forced expiratory volume in 1 second and diffusing capacity for carbon monoxide at discharge were 43% and 62%, respectively, of predicted. Rehabilitation has been excellent, and all survivors are active and free of supplemental oxygen. During the study, the following treatment strategies have evolved: (1) University of Wisconsin solution has replaced Euro-Collins' solution for pulmonary preservation; (2) direct bronchial revascularization with the internal thoracic artery now is used; (3) an algorithm-based variable dose OKT3 induction regimen has resulted in a major reduction in dosage; and (4) infectious disease management focuses on the prophylaxis of cytomegalovirus and fungal infection using prolonged ganciclovir and early itraconazole therapy as well as the avoidance of Epstein-Barr virus mismatches. Single-lung transplantation for emphysema has excellent early results with continuing evolving management strategies.

Long-term functional results after bilateral lung transplantation. Bordeaux Lung and Heart-Lung Transplant Group

Between February 1988 and January 1992, 61 patients have undergone bilateral lung transplantations (42 heart-lung and 19 double-lung) in Bordeaux. The underlying diseases were primary or secondary hypertension (20), emphysema (22), or other diseases including cystic fibrosis, pulmonary fibrosis, silicosis, and sarcoidosis (19). Actuarial survival for double-lung and heart-lung transplant recipients was 66% and 72% at 1 year and 57% and 53% at 3 years, respectively. Forty-two patients were still alive 6 months after operation, and we studied their pulmonary function at the short and long term. All parameters except arterial carbon dioxide tension had improved dramatically at 6 months (p < 0.0001). Vital capacity, forced expiratory volume in 1 second, and forced expiratory flow rate between 25% and 75% of vital capacity were at 79% +/- 3%, 92% +/- 5%, and 105% +/- 8% of the predicted values, respectively. Arterial oxygen tension was 88 +/- 3 mm Hg. Nine months after operation, a slight decrease in forced expiratory volume in 1 second and forced expiratory flow rate between 25% and 75% of vital capacity appeared but values remained more than 75% predicted. This was related to the occurrence of obliterative bronchiolitis in 6 patients (14%). At 9 months, flow rates and oxygen tension of these 6 patients were highly different from those of patients free of obliterative bronchiolitis (p < 0.0002 for flow rates and p < 0.01 for oxygen tension). Only 1 patient required retransplantation. The others are living an almost normal life. Our results are discussed in view of the published reports on single-lung transplantation. Short-term results of bilateral lung transplantation are thus excellent and maintained on a long-term basis. Therefore, in our opinion, bilateral lung transplantation is the therapy of choice for pulmonary hypertension and emphysema.