Single- versus double-lung transplantation for pulmonary hypertension

Single Lung Transplant Remains a Viable Option for Patients With Severe Secondary Pulmonary Hypertension

BACKGROUND

Although double lung transplant is recommended in patients with severe secondary pulmonary hypertension (SPH), our institutional experiences suggest a role for single lung transplant in these patients. Here, we review our experience prioritizing single lung transplant in patients with SPH to minimize their surgical burden.

METHODS

We conducted a retrospective review of our lung transplant database to identify patients with SPH who underwent single lung transplant. Patients were stratified as either mild SPH (mean pulmonary artery pressure 25-40 mm Hg) or severe SPH (mean pulmonary artery pressure >40 mm Hg). Singe lung recipients without PH transplanted over the same time were also examined.

RESULTS

Between January 2017 and December 2019, 318 patients underwent single lung transplantation; 217 had mild SPH (68%), and 59 had severe SPH (18.5%). Forty-two patients without PH underwent single lung transplant. When the groups were compared, significantly higher pulmonary vascular resistance was noted in the severe SPH group, and obesity was noted in both the mild and severe SPH groups. Although the severe SPH group required more intraoperative cardiopulmonary support (37.3% versus 10.3% versus 4.7%, P < 0.05), there were no significant differences in most major postoperative parameters, including the duration of postoperative mechanical ventilation or the incidence of severe primary graft dysfunction. Survival 1 y posttransplant was not significantly different among the groups (93.2% versus 89.4% versus 92.9%, P = 0.58).

CONCLUSIONS

Our experience supports the option of single lung transplantation with appropriate intraoperative mechanical circulatory support in patients with SPH. This strategy is worth pursuing, especially with ongoing donor lung shortages.

Double Lung Transplantation Bridged With Direct Central Ambulatory Veno-Arterial Extracorporeal Membrane Oxygenation in a Pulmonary Hypertension Patient With Extreme Mediastinal Shift

Lung transplantation is increasingly being performed for end-stage lung disease in patients with bronchiectasis and pulmonary hypertension. Outcomes of bilateral lung transplantation (BLT) are better in patients with pulmonary hypertension, whereas single lung transplant remains a controversy in bronchiectasis with fear of infections from the residual diseased lung. However, in patients with adhesions and extreme structural changes due to severe disease, BLT may be considered technically challenging. We describe a case of successful management of a patient with bronchiectasis-induced lung disease causing extreme mediastinal shift with a BLT. The patient was successfully bridged to transplant with central veno-arterial extracorporeal membrane oxygenation (VA-ECMO) for acute decompensated pulmonary hypertension while awaiting transplantation.

Surgical management of giant pulmonary artery aneurysms in patients with severe pulmonary arterial hypertension

BACKGROUND AND AIM

Giant aneurysm of the pulmonary artery (PAA) is an extremely rare condition that may develop in patients with pulmonary arterial hypertension (PAH) which may be complicated by rupture, dissection or intravascular thrombus formation. The aim of this study was to examine available literature with regard to surgical strategies in patients undergoing transplantation for PAH with PAA.

RESULTS

These patients were traditionally considered for heart-lung transplantation but more recently, there have been reports of successful lung transplantation with reconstruction of the pulmonary artery.

CONCLUSIONS

Unless there is a mandatory indication for heart-lung transplantation, patients with PAH and PAA can undergo lung transplantation and reconstruction of the pulmonary artery without compromising the outcome.

Advanced Circulatory Support and Lung Transplantation in Pulmonary Hypertension

Pulmonary arterial hypertension (PAH) is a progressive fatal disease. Although medical therapies have improved the outlook for these patients, there still exists a cohort of patients with PAH who are refractory to these therapies. Lung transplantation (LT), and in certain cases heart-lung transplantation (HLT), is a therapeutic option for patients with severe PAH who are receiving optimal therapy yet declining. ECMO may serve as a bridge to transplant or recovery in appropriate patients. Although, the mortality within the first 3 months after transplant is higher in PAH recipients than the other indications for LT, and the long-term survival after LT is excellent for this group of individuals. In this review, we discuss the indications for LT in PAH patients, when to refer and list patients for LT, the indications for double lung transplant (DLT) versus HLT for PAH patients, types of advanced circulatory support for severe PAH, and short and long-term outcomes in transplant recipients with PAH.

Not All Septal Defects Are Equal: Outcomes of Bilateral Lung Transplant With Cardiac Defect Repair vs Combined Heart-Lung Transplant in Patients With Eisenmenger Syndrome in the United States

BACKGROUND

Thoracic transplantation is considered for patients with Eisenmenger syndrome (ES) who have refractory right ventricular failure despite optimal therapy for pulmonary arterial hypertension. This study compared the outcomes of bilateral lung transplantation (BLT) with cardiac defect repair vs combined heart-lung transplantation (HLT).

RESEARCH QUESTION

This study presents an updated analysis using a US national registry to evaluate the outcomes of patients diagnosed with ES who underwent HLT or BLT with repair of cardiac defects.

STUDY DESIGN AND METHODS

This study identified patients with ES who underwent thoracic transplantation from 1987 to 2018 from the United Network for Organ Sharing database. Survival curves were estimated by using the Kaplan-Meier method and were compared by using the log-rank test.

RESULTS

During the study period, 442 adults with ES underwent thoracic transplantation (316 HLTs and 126 BLTs). Following BLT, overall survival 1, 5, and 10 years' posttransplant was 63.1%, 38.5%, and 30.2%, respectively. Following HLT, overall survival 1, 5, and 10 years' posttransplant was 68.0%, 47.3%, and 30.5% (P = .6). When survival analysis was stratified according to type of defect, patients with an atrial septal defect had better survival following BLT than following HLT (88.3% vs 63.2% 1 year posttransplant, P < .01; 71.1% vs 49.8% 3 years' posttransplant, P < .01; and 37.4% vs 29.9% 10 years' posttransplant, P = .08). Patients with a ventricular septal defect (VSD) exhibited better survival following HLT than following BLT (78.2% vs 49.6% 1 year posttransplant, P < .01; 55.6% vs 34.3% 5 years' posttransplant, P < .01; and 35.7% vs 26.5% 10 years' posttransplant, P = .03). The most common cause of mortality in patients with VSD undergoing BLT was cardiac ventricular failure.

INTERPRETATION

This study suggests that the best transplant option for patients with VSD remains HLT, which prevents subsequent development of ventricular failure. BLT with cardiac defect repair should be considered as the first-line treatment option in patients with ES due to an uncorrected atrial septal defect. These patients can be considered to have isolated and reversible right ventricular failure akin to patients with advanced pulmonary arterial hypertension.

Characteristics, Trends, and Predictors of Specialty Palliative Care Utilization after Lung Transplantation

Background: Lung transplant recipients who experience serious illness could benefit from specialty palliative care (SPC), but evidence suggests that referral has been rare. Objective: Examine the characteristics of post-transplant SPC encounters, utilization trends, and patient characteristics associated with SPC at a center with established SPC services. Design: Retrospective cohort study of SPC utilization by 597 lung transplant recipients transplanted between 2010 and 2015. We collected data on pretransplant demographics and post-transplant SPC encounters, including timing, location, and referral reasons. Cumulative incidence of SPC and patient characteristics associated with SPC were examined by competing risks methods. Utilization in the first two post-transplant years was compared between subcohorts defined by year of transplantation. Results: SPC cumulative incidence was 27% and 43% at one and five years. More than 60% of encounters occurred in the first post-transplant year including 34% during the index transplant hospitalization. Over 90% of encounters occurred in the inpatient setting. The majority of consults were for symptom management. From 2010 to 2015 inpatient utilization in the first two post-transplant years increased from 23% to 42%, and outpatient utilization increased from 2% to 16%. Accounting for increasing utilization, pretransplant SPC and double-lung transplantation were associated with greater incidence of post-transplant SPC. Conclusions: Lung transplant recipients may have palliative care needs early after transplantation. Increasing utilization suggests greater awareness of or changing attitudes about the utility of SPC for lung transplant recipients. Understanding transplant recipients' palliative care needs and transplant physicians' views of SPC is critical to improving the provision of SPC in lung transplantation.

Single vs. bilateral lung transplantation: when and why

PURPOSE OF REVIEW

Lung transplantation is a life-saving treatment for several end stage lung diseases. Over the last two decades, the number of lung transplantation performed worldwide has steadily increased but several thousand people still die every year waiting for lung transplantation. However, the optimal procedure for lung transplantation in non-septic lung conditions remains debatable.

RECENT FINDINGS

In pulmonary fibrosis and COPD, many recent studies suggest superiority of bilateral lung transplantation over single lung transplantation when long-term survival is evaluated; consequently, bilateral lung transplantation has been favored by many lung transplantation centers. However, the quality of evidence to support the superiority of bilateral lung transplantation remains low in the absence of prospective studies, and other available studies do not show differences in outcomes between the two types of procedure.

SUMMARY

In the absence of good high quality evidence, it is difficult to make strong general recommendations for the type of lung transplant, and the decision often has to be individualized. However, the number of recipients on the wait list continues to surpass the amount of available organs and due consideration needs to be given to single lung transplantation as an option whenever possible.

Long-Term Physical HRQOL Decreases After Single Lung as Compared With Double Lung Transplantation

BACKGROUND

Single lung transplantation (SLT) and double lung transplantation (DLT) are associated with differences in morbidity and mortality, although the effects of transplant type on patient-reported outcomes are not widely reported and conclusions have differed. Previous studies compared mean health-related quality of life (HRQOL) scores but did not evaluate potentially different temporal trajectories in the context of longitudinal follow-up. To address this uncertainty, this study was designed to evaluate longitudinal HRQOL after SLT and DLT with the hypothesis that temporal trajectories differ between SLT and DLT.

METHODS

Patients transplanted at a single institution were eligible to be surveyed at 1 month, 3 months, 6 months, and then annually after transplant using the Short Form 36 Health Survey, with longitudinal physical component summary (PCS) and mental component summary (MCS) scores as the primary outcomes. Multivariable mixed-effects models were used to evaluate the effects of transplant type and time posttransplant on longitudinal PCS and MCS after adjusting age, diagnosis, rejection, Lung Allocation Score quartile, and intubation duration. Time by transplant type interaction effects were used to test whether the temporal trajectories of HRQOL differ between SLT and DLT recipients. HRQOL scores were referenced to general population norms (range, 40 to 60; mean, 50 ± 10) using accepted standards for a minimally important difference (½ SD, 5 points).

RESULTS

Postoperative surveys (n = 345) were analyzed for 136 patients (52% male, 23% SLT, age 52 ± 13 years, LAS 42 ± 12, follow-up 37 ± 29 months [range, 0.6 to 133]) who underwent lung transplantation between 2005 and 2016. After adjusting for model covariates, overall posttransplant PCS scores have a significant downward trajectory (p = 0.015) whereas MCS scores remain stable (p = 0.593), with both averaging within general population norms. The time by transplant type interaction effect (p = 0.002), however, indicate that posttransplant PCS scores of SLT recipients decline at a rate of 2.4 points per year over the total observation period compared to DLT. At approximately 60 months, the PCS scores of SLT recipients, but not DLT recipients, fall below general population norms.

CONCLUSIONS

The trajectory of physical HRQOL in patients receiving SLT declines over time compared with DLT, indicating that, in the longer term, SLT recipients are more likely to have physical HRQOL scores that fall substantively below general population norms. Physical HRQOL after 5 years may be a consideration for lung allocation and patient counseling regarding expectations when recommending SLT or DLT.

Single versus bilateral lung transplantation: do guidelines exist?

An ongoing debate exists between proponents of single or double lung transplantation for end-stage pulmonary disease. Short-term and long-term outcomes, as well as individual and societal benefits are some of the key considerations. This article examines the evidence that directly compares these two approaches and informs the debate about the relative merits of single and bilateral transplantation.

Lung transplantation and atrial septostomy in pulmonary arterial hypertension

This article summarizes the current literature regarding surgical interventions in pulmonary hypertension, excluding chronic thromboembolic pulmonary hypertension. The article discusses the use of atrial septostomy in patients meeting criteria as well as single, double, and heart-lung transplantation.

Transplantation for Idiopathic Pulmonary Arterial Hypertension

Background—

Lung transplantation and heart-lung transplantation represent surgical options for treatment of medically refractory idiopathic pulmonary arterial hypertension. The effect of the lung allocation score on wait-list and transplantation outcomes in patients with idiopathic pulmonary arterial hypertension is poorly described.

Methods and Results—

Adults diagnosed with idiopathic pulmonary arterial hypertension and listed for transplantation in the 80 months before and after the lung allocation score algorithm was implemented (n=1430) were identified in the United Network for Organ Sharing thoracic registry. Patients were stratified by organ listed and pre– and post–lung allocation score era. The cumulative incidences of transplantation and mortality for wait-listed patients in both eras were appraised with competing outcomes analysis. Posttransplantation survival was assessed with the Kaplan-Meier method. These analyses were repeated in propensity-matched subgroups. Cox proportional hazards analysis evaluated the effect of prelisting and pretransplantation characteristics on mortality. We found that patients in the post–lung allocation score era had significantly worse comorbidities; nevertheless, both lung transplantation and heart-lung transplantation candidates in this era enjoyed lower wait-list mortality and a higher incidence of transplantation in unmatched and propensity-matched analyses. On multivariable analysis, heart-lung transplantation and double-lung transplantation were associated with improved survival from the time of wait-listing, as was being listed at a medium- to high-volume institution. Donor/recipient sex matching predicted posttransplantation survival.

Conclusions—

The incidence of transplantation has increased while wait-list mortality has decreased in patients with idiopathic pulmonary arterial hypertension wait-listed for transplantation in the post–lung allocation score era. Both heart-lung transplantation and double-lung transplantation are predictive of survival in transplantation candidates with idiopathic pulmonary arterial hypertension, as is being listed at a medium- to high-volume institution. Donor/recipient sex matching is associated with better posttransplantation survival.

Surgical treatment of pulmonary hypertension: Lung transplantation

Pulmonary hypertension (PH) is a serious and progressive disorder that results in right ventricular dysfunction that lead to subsequent right heart failure and death. When untreated the median survival for these patients is 2.8 years. Over the past decade advances in disease specific medical therapy considerably changed the natural history. This is reflected in a threefold decrease in the number of patients undergoing lung transplantation for PH which used to be main stay of treatment. Despite the successful development of medical therapy lung transplant still remains the gold standard for patients who fail medical therapy. Referral for lung transplant is recommended when patients have a less than 2-3 years of predicted survival or in NYHA class III or IV. Both single and bilateral lung transplants have been successfully performed for PH but outcome analyses and survival comparisons generally favor a bilateral lung transplant.

Pulmonary hypertension before first and second lung transplantation

BACKGROUND

Pulmonary hypertension (PH) is frequently encountered in patients with advanced lung disease before the first and second lung transplantation. We sought to determine whether there is any relationship between pulmonary hemodynamics obtained before first and second lung transplantation. We also assessed whether PH has prognostic implications in lung transplant patients going for second transplantation.

METHODS

We included consecutive adult (16-yr-old or older) patients who underwent lung re-transplantation, between 1997 and 2009, and had right heart catheterization before their first and second lung transplantation.

RESULTS

Eighteen patients were included in the study. Age at first transplantation was 50.4 (SD 10.4) yr, and bronchiolitis obliterans syndrome (BOS) in the transplanted lung was the only indication for re-transplantation. PH was observed in 39% of the patients before the first lung transplant and in 56% of the subjects before re-transplantation (p = 0.91). Pre-capillary PH was present in 28% (n = 5) and 33% (n = 6) of the patients before first and second lung transplantation, respectively. None of the hemodynamic variables obtained before the first transplant predicted the development of PH before re-transplantation. PH before re-transplantation did not predict survival or development of BOS after re-transplantation.

CONCLUSIONS

PH before initial lung transplantation did not predict the development of PH before the second transplantation. In our cohort, PH before second lung transplantation did not predict outcomes after re-transplantation.

Lung transplantation for pulmonary hypertension

Although medical therapies for pulmonary arterial hypertension have greatly improved, it remains a chronic and fatal disease. For patients who are refractory to medical therapy, lung transplantation is an important treatment option. This review discusses issues pertaining to indications for transplant, preparation for transplant and listing, operative issues, and outcomes for patients with pulmonary arterial hypertension.

Combining tricuspid valve repair with double lung transplantation in patients with severe pulmonary hypertension, tricuspid regurgitation, and right ventricular dysfunction

BACKGROUND

Concomitant tricuspid valve repair (TVR) and double lung transplantation (DLTx) has been a surgical option at our institution since 2004 in an attempt to improve the outcome of DLTx for end-stage pulmonary hypertension, severe tricuspid regurgitation, and right ventricle (RV) dysfunction. This study is a review of that single institutional experience.

METHODS

Consecutive cases of concomitant TVR and DLTx performed between 2004 and 2009 (TVR group, n = 20) were retrospectively compared with cases of DLTx alone for severe pulmonary hypertension without TVR (non-TVR group, n = 58).

RESULTS

There was one in-hospital death in the TVR group. The 90-day and 1- and 3-year survival rates for the TVR group were 90%, 75%, and 65%, respectively, which were not significantly different from those for the non-TVR group. The TVR group required less inotropic support and less prolonged mechanical ventilation in the ICU. Follow-up echocardiography demonstrated immediate elimination of both volume and pressure overload in the RV and tricuspid regurgitation in the TVR group. Notably, there was a significantly lower incidence of primary graft dysfunction following transplantation in the TVR group (P < .05). Pulmonary functional improvement shown by an FEV(1) increase after 6 months was also significantly better in the TVR group (40% vs 20%, P < .05).

CONCLUSIONS

Combined TVR and DLTx procedures were successfully performed without an increase in morbidity or mortality and contributed to decreased primary graft dysfunction. In our experience, this combined operative approach achieves clinical outcomes equal or superior to the outcomes seen in DLTx patients without RV dysfunction and severe tricuspid regurgitation.

[Surgical treatment of pulmonary arterial hypertension]

INTRODUCTION

Pulmonary arterial hypertension (PAH) is a severe disease that has undergone a dramatic improvement in therapeutic management over the past 20 years. Among the new therapeutic options, surgery has the potential to dramatically improve or, in some cases, cure PAH.

BACKGROUND

Surgical treatment of PAH includes pulmonary endarterectomy which can cure PAH when the cause is obstruction of the pulmonary arteries by fibrous tissue resulting from pulmonary embolism, by tumours as angiosarcomas, and echinococcus cysts. Transplantation is required in end-stage PAH after failure of medical treatment. Atrial septostomy and Potts procedure are palliative surgical procedures that can delay transplantation.

VIEWPOINT

Extracorporeal cardiopulmonary support is the latest surgical improvement, not only as a bridge to transplantation in end-stage PAH but also during recovery after transplantation or pulmonary endarterectomy.

CONCLUSIONS

Surgery is part of the therapeutic management of PAH. Dialogue between physicians and surgeons is a prerequisite for any reasoned therapeutic decision.

Surgical Treatment of Pulmonary Arterial Hypertension

Significant advances in the treatment of pulmonary arterial hypertension have occurred in the last several years. The decision to refer a patient for transplantation requires a dynamic approach. Candidate selection and timing of referral to transplant centers is critical for success, particularly with current allocation protocols that do not take into account the severity of illness. Though long-term success is tempered by chronic allograft dysfunction and infection, considerable improvements in outcomes have established lung transplantation for pulmonary arterial hypertension as an efficacious and life-prolonging treatment. However, transplantation should be reserved for patients who have failed the best available medical therapy. Ideally, transplantation occurs when the clinically deteriorating patient has enough reserve to survive long enough to be transplanted but is not debilitated enough to jeopardize the graft. There is significant uncertainty with regard to this ideal.

Long-term outcome of lung and heart-lung transplantation for idiopathic pulmonary arterial hypertension

BACKGROUND

The survival after lung and heart-lung transplantation for idiopathic pulmonary arterial hypertension has been reportedly the lowest among the major diagnostic categories of lung transplant recipients.

METHODS

Retrospective analysis was performed for lung and heart-lung transplant recipients for idiopathic pulmonary arterial hypertension from 1982 to 2006. The patients were divided into 2 groups, based on the era; group 1: 1982 to 1993, and group 2: 1994 to 2006. Since 1994, we have introduced our current protocols including prostaglandin E1 and nitroglycerin for donor lung preservation, and lung protection with cold and terminal warm blood pneumoplegia as well as immunosuppression with alemtuzumab induction. These modifications were introduced in different years over a wide span of time (1994 to 2003).

RESULTS

Group 1 had 59 patients (35 +/- 1 years old, ranging 15 to 53, 20 male and 39 female) with 7 single lung, 11 double lung, and 41 heart-lung, whereas group 2 had 30 (43 +/- 2 years old, ranging 17 to 65, 9 male and 21 female) with 2 single, 20 double, and 8 heart-lung transplantations. The recipient age was significantly (p = 0.004) higher in group 2, and group 2 had significantly older (35 +/- 3 vs 26 +/- 1, p = 0.002) and more female donors (73% vs 41%, p = 0.007) compared with group 1. The actuarial survival was significantly (p = 0.004) better in group 2 with 86% at 1 year, 75% at 5 years, and 66% at 10 years compared with group 1 with 58% at 1 year, 39% at 5 years, and 27% at 10 years.

CONCLUSIONS

With our current pulmonary protection and immunosuppression, the long-term outcome of lung and heart-lung transplantation for idiopathic pulmonary arterial hypertension is excellent.

Surgical therapies for pulmonary arterial hypertension

Surgical therapies for the treatment of pulmonary arterial hypertension typically are reserved for patients who are deemed to be refractory to medical therapy and have evidence of progressive right-sided heart failure. Atrial septostomy, a primarily palliative procedure, may stave off hemodynamic collapse from right-sided heart failure long enough to permit a more definitive surgical treatment such as lung or combined heart-lung transplantation. This article discusses indications for and results of atrial septostomy and lung and heart-lung transplantation in patients who have pulmonary arterial hypertension.

Reversal of idiopathic pulmonary arterial hypertension and allograft pneumonectomy after single lung transplantation

Prior to the advent of effective medical therapies, the only treatment option for patients with idiopathic pulmonary arterial hypertension (IPAH) was lung transplantation. We present the case of a woman who underwent single-lung transplantation for the treatment of IPAH > 10 years ago in whom chronic rejection developed. Despite complete obliteration of the allograft, it was noted that her PA pressure levels had almost normalized. Therefore, an allograft pneumonectomy was performed. To our knowledge, this is the first reported case of the regression of pulmonary vascular disease following lung transplantation with subsequent successful removal of the allograft.

Impact of secondary pulmonary hypertension on lung transplant outcome

INTRODUCTION

Secondary pulmonary hypertension (SPH), defined as a mean pulmonary artery pressure (PAM) greater than 25 mm Hg, complicates end-stage lung diseases of varying etiology. Although previous studies have suggested that SPH does not adversely affect outcome, no study has assessed the impact of the degree of SPH.

METHODS

A retrospective review of the lung transplant database was used to identify patients who underwent either single-lung (SLT) or bilateral lung transplantation (BLT) complicated by SPH. SPH patients were stratified into low SPH (PAM = 30-40 mm Hg) and high SPH (PAM > or = 40 mm Hg). Each group was further sub-categorized into SLT or BLT. Patients with a heart-lung transplant or primary pulmonary hypertension were excluded. Recipients without pulmonary hypertension transplanted over the same time were used as controls. Data are reported as controls vs low SPH vs high SPH.

RESULTS

One hundred-four patients received lung transplants between August 1998 and March 2003. There were 45 patients (18 men and 27 women) with SPH. Of these, 28 patients had low SPH, and 17 patients had high SPH. Forty-two patients (18 men and 24 women) without PH were the controls. There were no significant differences between groups except pre-operative oxygen dependence (81% vs 100% vs 94%, respectively) and use of CPB (28.6% vs 57.1% vs 64.7%, respectively). PAO2-PaO2 gradients and PaO2/FIO2 ratios were significantly worse in the high SPH group (116.2 vs 132.9 vs 186.3; p < 0.006) and (277.8 vs 234.3 vs 214.4; p < 0.026) respectively. There was no statistical difference in length of mechanical ventilation or duration of intensive care unit stay between groups. PAMs were significantly different pre-operatively (22.2 +/- 0.8 vs 34.0 +/- 0.6 vs 47.8 +/- 2.0; p < 0.001) and post-operatively (20.9 +/- 1.1 vs 23.7 +/- 1.3 vs 24.8 +/- 2.1; p < 0.001). There were no operative deaths. There were 3 early deaths in the control group, 1 in the low SPH group, and 3 in the high SPH group, none were related to pulmonary hypertension. Actuarial survival at 12, 24, and 48 months was not significantly different among the groups nor between SLT or BLT with SPH.

CONCLUSION

Although SPH increases the risk of reperfusion injury; survival is equivalent with mild or moderate pulmonary hypertension. Either SLT or BLT may be used in patients with SPH without compromising outcome. This has the added benefit of expanding the donor pool.

Use of cardiopulmonary bypass for lung transplantation: a 10-year experience

OBJECTIVE

The use of cardiopulmonary bypass (CPB) for lung transplantation (LTx) has been reported previously. This study reports the authors' experience of planned and unplanned use of cardiopulmonary bypass for LTx.

DESIGN

Case series.

SETTING

A university teaching hospital.

PARTICIPANTS

Patients undergoing LTx.

INTERVENTIONS

A retrospective analysis of the charts of all patients having undergone LTx over the last 10 years.

MEASUREMENTS AND MAIN RESULTS

Among 140 LTx, 23 (16%) were performed with the use of CPB. CPB was planned in 11 cases and unplanned in the 12 other cases. The use of CPB is associated with a longer period of postoperative mechanical ventilation, more pulmonary edema, more blood transfusion requirement, and an increase in postoperative mortality at 48 hours and 1 month. Surgical difficulties related to the dissection of the native left lung and acute right ventricular failure are the main reasons for unscheduled use of CPB.

CONCLUSION

Scheduled and unscheduled CPB for LTx are associated with an increased mortality at 1 month and 1 year.

Impact of recipient age and procedure type on survival after lung transplantation for pulmonary fibrosis

BACKGROUND

The decision to perform single-lung (SLT) or bilateral sequential lung (BSLT) transplantation in patients with pulmonary fibrosis is controversial. Some centers use recipient age (<50 years) as a criterion to select BSLT over SLT, but the rationale for this approach is not well established.

METHODS

Eight hundred twenty-one patients (636 SLT, 185 BSLT), aged 30 to 69 years, who were recipients of transplants for pulmonary fibrosis in the United States between 1994 and 2000 were reported to the United Network for Organ Sharing. Survival was compared by procedure type within three age groups (30 to 49 years, 50 to 59 years, and 60 to 69 years) using the Kaplan-Meier method. Multivariate logistic regression analysis was used to calculate risk-adjusted mortality within 1-month after transplantation, and proportional hazards regression was used to calculate risk-adjusted mortality after 1 month.

RESULTS

Early (1-month) and late (3-year) survival in recipients aged 30 to 49 years was significantly better with SLT than BSLT (early, 90.9% versus 77.1%; late, 63.8% versus 46.2%, respectively; p = 0.02). Survival was also significantly better with SLT than BSLT at these time points in those patients aged 50 to 59 years (early, 89.5% versus 81.7%; late, 53.6% versus 46.7%, respectively; p = 0.03). When posttransplant survival was reanalyzed contingent on survival to 1 month, no significant difference in survival by procedure type (SLT versus BSLT) was detected for any age group. Multivariate analysis of survival, adjusted for other known risk factors, as well as propensity analysis, yielded similar results.

CONCLUSIONS

Patients younger than 60 years of age who were recipients of transplants for pulmonary fibrosis appear to have better survival with SLT than with BSLT. Although the basis for this observation is unclear, events occurring in the early period (first month) after transplantation may play a role. Further studies will be needed, but these data do not appear to support the preferential use of BSLT for younger patients with pulmonary fibrosis.

The transplant recipient for nontransplant surgery

The transplant recipient has traded a life-threatening illness for a chronically immunosuppressed state. Subsequent anesthetic management for non-transplant surgical procedures may be challenging. The anesthesia provider must be aware of the degree of post-transplant organ dysfunction and alter anesthesia techniques accordingly. This article reviews the anesthetic concerns for patients who have undergone a variety of organ transplants.

Anesthetic implications for lung transplantation

Anesthetic challenges regarding lung transplantation are related to the expanded spectrum of diseases for which lung transplantation is offered and to the interval changes in health status likely to occur as patients wait longer for an organ to become available. Particular attention to avoiding or reducing the impact of increases in pulmonary vascular resistance and right heart failure are important and may necessitate cardiopulmonary bypass. Intraoperative and postoperative ventilator management should account for differences in pulmonary compliance after the new lung is implanted. Minimizing intravenous fluids without compromising end organ perfusion may avoid or reduce postoperative respiratory insufficiency.

Interventional and surgical modalities of treatment for pulmonary arterial hypertension

Beyond medical therapy, different interventional and surgical approaches exist for treatment of pulmonary arterial hypertension (PAH). Atrial septostomy has been applied in patients with lack of response to medical therapy in the absence of other surgical treatment options. With growing experience, procedure-related death rates have been reduced to 5.4%, and the most suitable patient group has been identified among patients with a mean right atrial pressure between 10 and 20 mm Hg. Pulmonary endarterectomy is the accepted form of treatment for patients with chronic thromboembolic pulmonary hypertension. Establishing the diagnosis and the classification of the type of lesions by pulmonary angiography is crucial for optimal patient selection. Perioperative mortality rates have been reduced to <10% in experienced centers, and the hemodynamic improvement is dramatic and sustained. Lung and heart-lung transplantation remains the procedure of choice for patients unsuitable for other treatment modalities. Timing of the procedure is difficult because waiting times vary between centers and usually are in a high range. Early referral of patients unresponsive to other treatment forms is therefore of importance to avoid transplantation of patients with established significant comorbidity. The survival rate during the first five years after transplantation for PAH is intermediate among the lung diseases, lower than chronic obstructive pulmonary disease but higher than idiopathic pulmonary fibrosis.

Surgical Treatments/Interventions for Pulmonary Arterial Hypertension

While considerable advances have been achieved in the medical treatment of pulmonary arterial hypertension (PAH) over the past decade, surgical and interventional approaches continue to have important roles in those patients for whom medical therapy is unavailable or has been unsuccessful. These techniques include pulmonary thromboendarterectomy for chronic thromboembolic pulmonary hypertension, thoracic transplantation, and atrial septostomy. This chapter will provide evidence-based recommendations for the selection and timing of surgical and interventional treatments of PAH for physicians involved in the care of these complex patients.

A Survey of Clinical Practice of Lung Transplantation in North America

OBJECTIVES

The clinical practice of lung transplantation (LT) varies widely among transplant centers. The objective of this study was to determine the practice patterns of North American lung transplant programs in specific areas that are considered controversial by most lung transplant practitioners.

METHODS

The Transplant/Immunology Network of the American College of Chest Physicians (ACCP) designed a survey and distributed it through the ACCP using a Web-based survey tool. The survey was divided into the following two sections: (1) patient selection issues; and (2) posttransplant management. Additional questions were asked about graft preservation, retransplantation, and living donor operations. A single 64-question survey was sent to each lung transplant program in the United Sates registered in the United Network of Organ Sharing database as of September 2001 and to each of the five active Canadian programs.

RESULTS

The survey was conducted in September and October 2002. Fifty of 65 active centers completed the survey, for a response rate of 77%. The data are presented in graphic format as a percentage of respondents.

CONCLUSION

This survey provides a large, time-sensitive database summarizing the clinical practice of LT in North America. In general, the survey responses demonstrated a remarkable degree of consistency around patient selection criteria, but much greater variance in posttransplant management of lung transplant recipients. These findings may reflect the fact that a published selection criteria guideline exists, but no similar documents have been designed for postoperative management. Hopefully, postoperative areas with widely divergent approaches to management will foster future collaborative studies aimed at identifying the most appropriate practices.

Anesthetic management of the adult patient with congenital heart disease

As the number of CHD repairs in adults continues to increase, these operations will be performed in a wider variety of institutions and systems. Unfortunately, not all of these centers will have an optimal environment for correcting CHD in adults. This type of surgery is best accomplished in a facility specifically designed for treating adults with CHD. Optimal care of these patients is provided by cardiologists who are trained and experienced in pediatric and adult cardiology, by surgeons who are trained and experienced in treating CHD, and by anesthesiologists who are experienced in caring for adults with CHD. Whatever the setting, cardiac anesthesiologists involved in these cases must be thoroughly aware of the anesthetic implications for the unique pathophysiology of each patient, and they must not rely on their "usual" expectations of either true pediatric CHD or acquired adult heart disease.

Primary pulmonary hypertension

Primary pulmonary hypertension (PPH) is a rare disorder characterised by raised pulmonary-artery pressure in the absence of secondary causes. Precapillary pulmonary arteries are affected by medial hypertrophy, intimal fibrosis, microthrombosis, and plexiform lesions. Most individuals present with dyspnoea or evidence of right heart failure. Echocardiography is the best non-invasive test to screen for suspected pulmonary hypertension. The discovery of mutations in the coding region of the gene for bone morphogenetic protein receptor 2 in patients with familial and sporadic PPH may help not only to elucidate pathogenesis but also to direct future treatment options. The pathogenesis is not completely understood, but recent investigations have revealed many possible candidate modifier genes. Without treatment, the disorder progresses in most cases to right heart failure and death. With current therapies such as epoprostenol, progression of disease is slowed, but not halted. Many promising new therapeutic options, including prostacyclin analogues, endothelin-1-receptor antagonists, and phosphodiesterase inhibitors, improve clinical function and haemodynamic measures and may prolong survival.

Heart-lung or lung transplantation for Eisenmenger syndrome

BACKGROUND

The optimal therapy for end-stage Eisenmenger syndrome (ES) is unknown. We analyzed the United Network for Organ Sharing/International Society for Heart and Lung Transplantation Joint Thoracic Registry to determine predictors of survival.

METHODS

Univariate analysis was performed using Kaplan-Meier survival curves. Groups were compared using the log-rank test. Multivariate analysis was performed using a proportional hazards model.

RESULTS

There were 605 transplants performed between 1988 and 1998. The causes of ES included atrial septal defect (ASD) in 171, ventricular septal defect (VSD) in 164, multiple congenital anomalies (MCA) in 68 and patent ductus arteriosus (PDA) in 32. Procedures included 430 heart-lung (HLT), 106 bilateral lung, and 69 single lung transplants (LT). Survival after HLT was better than after LT on univariate analysis (p = 0.002). For HLT, survival at 30 days and 1 year was 80.7% and 70.1% compared with 68% and 55.2% for LT. Diagnosis was also a significant predictor of survival (p = 0.011), being best for VSD and MCA (1-year survival 71.4% and 77.6%). There was a highly significant benefit of HLT over LT for VSD patients (p = 0.0001). Diagnosis, the combination of diagnosis and procedure, recipient age, recipient gender, donor age, ischemic time and recipient status were significant in a multivariate model. Multivariate analysis confirmed the superior prognosis of patients with VSD or MCA (p = 0.007 and p = 0.022, respectively) and suggested that the adverse effect of LT was predominately in patients with VSD (risk ratio 1.817, p = 0.035).

CONCLUSIONS

This analysis suggests that ES recipients are not a homogeneous group. Patients with VSD and MCA have the best prognosis. HLT appears to offer a survival benefit for patients with ES secondary to VSD and should be re-considered as the operation of choice.

Lung transplantation for pulmonary vascular disease

BACKGROUND

Pulmonary hypertension (PHT) is a lethal condition resulting in markedly diminished life expectancy. Continuous prostaglandin I2 infusion has made an important contribution to symptom management, but it is not a panacea. Lung or heart-lung transplantation remains an important treatment option for end-stage PHT patients unresponsive to prostaglandin I2. This study reviews the outcomes after transplantation for PHT in our program.

METHODS

A retrospective chart review was performed for 100 consecutive patients with either primary PHT (48%) or secondary PHT (52%) transplants since 1989. Living recipients were contacted to confirm health and functional status.

RESULTS

Fifty-five adult and 45 pediatric patients underwent 51 bilateral lung transplants, 39 single lung transplants, and 10 heart-lung transplants. Mean age was 23.7 years (range, 1.2 months to 54.8 years) and mean pre-transplant New York Heart Association class was 3.2. Pre-transplant hemodynamics revealed a mean right atrial pressure of 9.6+/-5.4 mm Hg and mean pulmonary artery pressure of 64+/-14.4 mm Hg. Hospital mortality was 17% with early death predominantly because of graft failure and infection. With an average follow-up of 5.0 years, 1- and 5-year actuarial survival was 75% and 57%, respectively. Mean pulmonary artery pressure on follow-up catheterization was 22+/-6.0 mm Hg, and mean follow-up New York Heart Association class was 1.3 (p < 0.001 for both compared with pre-transplant). Diagnosis and type of transplant did not confer a significant difference in survival between groups.

CONCLUSIONS

Whereas lung or heart-lung transplant for PHT is associated with higher early mortality than other pulmonary disease entities, it provides similar long-term outcomes with dramatic improvement in both quality of life and physiologic aspects.

Lung and heart-lung transplant practice patterns in pulmonary hypertension centers

BACKGROUND

Transplant practice patterns for pulmonary hypertension in the epoprostenol era are unknown.

METHODS

Thirty-five centers in North America, Europe, and Israel were surveyed regarding practice patterns for lung and heart-lung transplant.

RESULTS

New York Heart Association class and distance on a 6-minute walk were considered most useful for deciding who to refer for listing. Patients with New York Heart Association class I to II were referred for listing in 26% of centers, while 57% were classified as New York Heart Association class III or greater after epoprostenol failure. Twenty-nine of the 35 centers had transplant programs that performed approximately 75% of the International Registry volume annually. A double lung transplant was preferred by 83% of centers and heart-lung transplant in the remaining centers. The wait time for lung transplant averaged 16.8 months (range 4-36) and for heart-lung transplant averaged 21.3 months (range 6-36) and was significantly longer in the United States. The mean maximum age for heart-lung transplant was 51.4 years (range 35-65), double lung transplant 58.3 years (range 45-65), and single lung transplant 63.1 years (range 50-70). Fifty-three percent of centers transplant New York Heart Association class III or IV patients, 26% class IIIb-IV, and 21% only class IV. Eighty percent of centers use a transplant hold status. Major unqualified exclusions were hepatitis in 38%, 1 or more hepatic (90%) or renal (100%) criteria, smoking 97%, and obesity in 93%.

CONCLUSIONS

Physicians and patients should be aware of the considerable variability in practice patterns for transplantation in pulmonary hypertension, despite published guidelines.

Lung transplantation for primary and secondary pulmonary hypertension

BACKGROUND

Single lung transplantation (SLT) and bilateral lung transplantation (BLT) are routinely performed in patients with primary pulmonary hypertension (PPH) and secondary pulmonary hypertension (SPH). It is unclear which procedure is preferable. We reviewed our experience with lung transplants for PPH and SPH to determine if any advantage exists with SLT or BLT for either PPH or SPH.

METHODS

We reviewed the outcomes of all lung transplants performed for PPH or SPH for 4.5 years (July 1995 to January 2000). Survival was reported by the Kaplan-Meier method, and log rank analysis was used to determine significance. Statistical analyses of clinical data were performed using analysis of variance and chi2 analysis.

RESULTS

A total of 57 recipients met criteria for pulmonary hypertension with a mean pulmonary artery pressure of greater than or equal to 30 mm Hg. There were 15 patients with PPH and 40 patients with SPH. There were 6 patients who had SLTs and 9 patients who had BLTs in the PPH group; and there were 9 patients who had SLTs and 21 patients who had BLTs in the SPH group. We found a survival advantage for PPH patients who underwent BLTs at all time points up to 4 years (100% vs 67%; p < or = 0.02). There was no clear advantage to SLTs or BLTs for SPH. At 4 years there was a trend toward improved survival with SLTs (91% vs 75%) in SPH patients with a mean pulmonary artery pressure less than or equal to 40 mm Hg (p < or = 0.11) with equivalent survival (80%) in patients with a mean pulmonary artery pressure greater than or equal to 40 mm Hg. There was also a trend toward improved survival in patients with a mean pulmonary artery pressure greater than or equal to 40 mm Hg (PPH and SPH) with BLTs (88% vs 62%; p = 0.19). The incidence of rejection, infection, and other complications was comparable between SLTs and BLTs in each group.

CONCLUSIONS

We believe that BLT is the procedure of choice for PPH. The procedure of choice is less clear for SPH. Patients with SPH and a mean pulmonary artery pressure greater than 40 mm Hg may benefit from a BLT and those with a mean pulmonary artery pressure less than or equal to 40 mm Hg may do better with an SLT; however, no clear advantage is seen.

Lung transplantation for primary pulmonary hypertension

Recent progress in medical therapies has diminished the role of transplantation in the management of PPH during the past decade. Drug therapy is not effective in some patients, responses to therapy are not sustained over time in others, and drug side effects eventually limit the benefits of treatment in a few more. Lung transplantation therefore ultimately is the only alternative for patients whose PPH is severe and cannot be managed medically. Choosing the right patient as a transplant candidate and the right time to make the initial referral to a transplant center are the crucial initial steps in the transplantation process, and the long waiting time before transplantation must be integrated into this decision. The outcome of lung and heart-lung transplantation for PHH has been good but sobering. Functional recovery has been excellent, but long-term survival results have been limited by the high prevalence of chronic allograft rejection.

Medical therapy of pulmonary hypertension. Conventional therapies

The 1-, 3-, and 5-year survival rates of the patients included in the National Institute of Health Registry on Primary Pulmonary Hypertension were 77%, 41%, and 27% respectively. It is unclear to what extent better applied conventional therapy contributes to improved survival rates that now are reported with calcium-channel blockers, prostacyclin, or even transplantation. To date, by far the most favorable results are reported with high-dose calcium-channel blockers combined with anticoagulant therapy, with survival rates at 3 years approximately 100%. It has to be emphasized, however, that such exceptionally favorable results are to be expected only in a small minority of patients who should not be considered to be cured because, sooner or later, their disease will continue to evolve. Further improvements obviously are needed for most patients with PAH. Interesting developments are likely in the coming years, with new multidrug approaches to control pulmonary vasoreactivity and remodeling and, hopefully, also with progress in lung transplantation. The past 2 decades have witnessed important progress in the treatment of PAH. Although significant improvements in quality of life and survival rate have been obtained with prostacyclin therapy, and better perspectives now are offered with atrial septostomy and lung transplantation, conventional therapy also has evolved. Patients now are counseled more adequately regarding how to remain physically active while avoiding exercise-induced anginal pain or syncope. Invasive and potentially risky medical procedures have been restricted in favor of noninvasive and functional evaluations whenever possible. Risk factors such as appetite suppressants, pregnancy, and hypobaric hypoxia are now better appreciated. The indications of supplemental oxygen, inotropic agents, and diuretics have been refined based on improved pathophysiologic understanding. Most patients now benefit from anticoagulant therapy with coumarin derivatives, although some uncertainty remains about the optimal international normalized ratio to be achieved. Safer acute reversibility testing now is performed with fewer and shorter-acting agents that are more specific to the pulmonary circulation to select the small proportion of patients who benefit from long-term high-dose calcium-channel blocker therapy.

Lung transplantation at the turn of the century

Lung transplantation has become a viable treatment option for patients with end-stage lung disease. Donor selection and organ allocation must follow specific guidelines. Single, bilateral, and living-donor lobar transplantation have all been performed successfully for a variety of diseases. Complications include reimplantation response and airway complications. Rejection may occur in the hyperacute, acute, or chronic settings and requires judicious management with immunosuppression. Infection and malignancy remain potential complications of the commitment to lifelong systemic immunosuppression. Survival statistics have remained encouraging and continue to improve with experience. Improved exercise tolerance and quality of life have been demonstrated in the years following transplantation. Remaining obstacles include limited donor organ availability, long-term graft function, and patient survival. However, ongoing advances in immune tolerance and standardized training of physicians in the care of transplant patients should carry lung transplant forward in the twenty-first century.

Bronchial artery revascularization improves tracheal anastomotic healing after lung transplantation

The study aimed to clarify the role of direct bronchial artery revascularization (BAR) after en bloc double-lung (DLT) and heart-lung transplantation (HLT). Group I comprised eight patients with en bloc DLT or HLT and successful BAR, while group II included 14 DLT or HLT cases without BAR or with failed BAR. From these groups, 2 subgroups were extracted: group III, including 6 cases of en bloc DLT with successful BAR and group IV 10 HLT cases without or with failed BAR. Airway healing was evaluated at bronchoscopy and patency of BAR with angiography. Pulmonary viral, bacterial and fungal infections, rejections and bronchiolitis obliterans syndrome (BOS) were registered. Tracheal healing at 2 weeks and 3 months was better in group I than in group 1 (p = 0.003 and p = 0.05, respectively). Compared with group IV, tracheal anastomotic healing at 2 weeks was better in group III (p = 0.007) and tended to be better also after 3 months (p = 0.07). The incidence of infections, rejection or BOS did not differ between groups I and II. BAR thus improved healing of tracheal anastomosis.