Ten years experience with lung and heart-lung transplantation in primary and secondary pulmonary hypertension

Double-lung versus heart-lung transplantation for end-stage cardiopulmonary disease: a systematic review and meta-analysis

We compared posttransplant outcomes following double-lung transplantation (DLTx) and heart-lung transplantation (HLTx), based on a search of PubMed, Cochrane Library, and Embase, from inception to March 8, 2022, for studies that report outcomes of these procedures. We then performed a meta-analysis of baseline characteristics and posttransplant outcomes. Subgroup analyses were implemented according to indication, publication year, and center. This study was registered on PROSPERO (number CRD42020223493). Ten studies were included in this meta-analysis, involving 1230 DLTx patients and 1022 HLTx patients. The DLTx group was characterized by older donors (P = 0.04) and a longer allograft ischemia time (P < 0.001) than the HLTx group. The two groups had comparable 1-year, 3-year, 5-year, 10-year survival rates (all P > 0.05), with similar results identified in subgroup analyses. We found no significant differences in 1-year, 5-year, and 10-year chronic lung allograft dysfunction (CLAD)-free survival, length of intensive care unit stay and hospital stay, length of postoperative ventilation, in-hospital mortality, or surgical complications between the groups (all P > 0.05). Thus, DLTx provides similar posttransplant survival to HLTx for end-stage cardiopulmonary disease. These two procedures have a comparable risk of CLAD and other posttransplant outcomes.

Should there be an age limit for advanced therapies?

Combined heart lung transplant has become a rare procedure. However, there is a significant number of patients potentially benefitting from replacement of both heart and lungs. This represents a quite diverse patient population. Decisions in patient selection have to be adjusted to individual needs and distinct constellation of the patient. Age may be a risk factor, but should be carefully integrated into the evaluation of perioperative and long term risks.

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.

Unilateral interruption of pulmonary artery with pulmonary hypertension: a case for heart lung transplantation?

Unilateral interruption of pulmonary artery is a rare congenital anomaly which is usually associated with other congenital heart disease. Even more rarely it may occur in isolation. Most of the cases are incidentally detected in adulthood. Some cases develop pulmonary hypertension for yet unknown reasons; such cases usually present in infancy with right heart failure. Surgical correction in such cases is associated with adverse outcomes. Heart lung transplantation should be considered in such patients. We report a 3-year-old boy with interruption of right pulmonary artery with severe pulmonary hypertension and right heart failure who was considered for heart lung transplantation.

Intensive care, right ventricular support and lung transplantation in patients with pulmonary hypertension

Intensive care of patients with pulmonary hypertension (PH) and right-sided heart failure includes treatment of factors causing or contributing to heart failure, careful fluid management, and strategies to reduce ventricular afterload and improve cardiac function. Extracorporeal membrane oxygenation (ECMO) should be considered in distinct situations, especially in candidates for lung transplantation (bridge to transplant) or, occasionally, in patients with a reversible cause of right-sided heart failure (bridge to recovery). ECMO should not be used in patients with end-stage disease without a realistic chance for recovery or for transplantation. For patients with refractory disease, lung transplantation remains an important treatment option. Patients should be referred to a transplant centre when they remain in an intermediate- or high-risk category despite receiving optimised pulmonary arterial hypertension therapy. Meticulous peri-operative management including the intra-operative and post-operative use of ECMO effectively prevents graft failure. In experienced centres, the 1-year survival rates after lung transplantation for PH now exceed 90%.

Lung transplantation for idiopathic pulmonary arterial hypertension on intraoperative and postoperatively prolonged extracorporeal membrane oxygenation provides optimally controlled reperfusion and excellent outcome

OBJECTIVES

Lung transplantation for idiopathic pulmonary arterial hypertension has the highest reported postoperative mortality of all indications. Reasons lie in the complexity of treatment of these patients and the frequent occurrence of postoperative left ventricular failure. Transplantation on intraoperative extracorporeal membrane oxygenation support instead of cardiopulmonary bypass and even more the prolongation of extracorporeal membrane oxygenation into the postoperative period helps to overcome these problems. We reviewed our experience with this concept.

METHODS

All patients undergoing bilateral lung transplantation for idiopathic pulmonary arterial hypertension on intraoperative extracorporeal membrane oxygenation with or without prophylactic extracorporeal membrane oxygenation prolongation into the postoperative period between January 2000 and December 2014 were retrospectively analysed.

RESULTS

Forty-one patients entered the study. Venoarterial extracorporeal membrane oxygenation support was prolonged into the postoperative period for a median of 2.5 days (range 1–40). Ninety-day, 1-, 3- and 5-year survival rates for the patient collective were 92.7%, 90.2%, 87.4% and 87.4%, respectively. When compared with 31 patients with idiopathic pulmonary arterial hypertension transplanted in the same period of time without prolongation of extracorporeal membrane oxygenation into the postoperative period, the results compared favourably (83.9%, 77.4%, 77.4%, and 77.4%; P = 0.189). Furthermore, these results are among the best results ever reported for this particularly difficult patient population.

CONCLUSIONS

Bilateral lung transplantation for idiopathic pulmonary arterial hypertension with intraoperative venoarterial extracorporeal membrane oxygenation support seems to provide superior outcome compared with the results reported about the use of cardiopulmonary bypass. Prophylactic prolongation of venoarterial extracorporeal membrane oxygenation into the early postoperative period provides stable postoperative conditions and seems to further improve the results.

Mid-term results of bilateral lung transplant with postoperatively extended intraoperative extracorporeal membrane oxygenation for severe pulmonary hypertension

OBJECTIVES

In severe pulmonary hypertension, diastolic dysfunction of the left ventricle causes significant morbidity and mortality after lung transplantation, which may be successfully reversed using a protocol based on perioperative veno-arterial extracorporeal membrane oxygenation (ECMO) and early extubation. Here, we present echocardiographic data and mid-term outcomes.

METHODS

The records of lung transplanted patients at our institution between May 2010 and January 2016 were retrospectively reviewed. Echocardiography data were collected preoperatively, at discharge, 3 and 12 months after transplantation.

RESULTS

During the study period, 717 patients underwent lung transplantation at our institution, 38 (5%) patients being transplanted for severe pulmonary hypertension. All patients underwent bilateral lung transplantation on veno-arterial ECMO cannulated in the groin, through a sternum sparing thoracotomy in 36 (95%) patients. Extubation was performed early, after a median of 2 days, and awake ECMO was extended for at least 5 days after transplantation. The survival at 3 months, 1 year and 5 years was not different in comparison to patients transplanted for other underlying diseases ( P  = 0.45). At 1 year, tricuspid valve regurgitation had disappeared in all patients. The median of the left ventricular end-diastolic dimension improved from 40 (32-44) mm preoperatively to 45 (44-47) mm at 12 months after lung transplantation ( P  < 0.05). The median of the proximal right ventricular outflow diameter decreased to 25 (23-27) mm after 12 months, compared to 48 (43-51) mm preoperatively ( P  < 0.05).

CONCLUSIONS

The routine application of a prophylactic postoperative veno-arterial ECMO protocol in patients with severe pulmonary hypertension undergoing lung transplantation decreases postoperative mortality and favours achievement of normal cardiac function after 1 year.

Lung transplantation for severe pulmonary hypertension--awake extracorporeal membrane oxygenation for postoperative left ventricular remodelling

BACKGROUND

Bilateral lung transplantation (BLTx) is an established treatment for end-stage pulmonary hypertension (PH). Ventilator weaning failure and death are more common as in BLTx for other indications. We hypothesized that left ventricular (LV) dysfunction is the main cause of early postoperative morbidity or mortality and investigated a weaning strategy using awake venoarterial extracorporeal membrane oxygenation (ECMO).

METHODS

In 23 BLTx for severe PH, ECMO used during BLTx was continued for a minimum of 5 days (BLTx-ECMO group). Echocardiography, left atrial (LA) and Swan-Ganz catheters were used for monitoring. Early extubation after transplantation was attempted under continued ECMO.

RESULTS

Preoperatively, all patients had severely reduced cardiac index (mean, 2.1 L/min/m2). On postoperative day 2, reduction of ECMO flow resulted in increasing LA and decreasing systemic blood pressures. On the day of ECMO explantation (median, postoperative day 8), LV diameter had increased; LA and blood pressures remained stable. Survival rates at 3 and 12 months were 100% and 96%, respectively. Data were compared to two historic control groups of BLTx without ECMO (BLTx ventilation) or combined heart-lung transplantation for severe PH.

CONCLUSION

Early after BLTx for severe PH, the LV may be unable to handle normalized LV preload. This can be effectively bridged with awake venoarterial ECMO.

Heart-lung transplantation: pediatric indications and outcomes

As indications for heart-lung transplant (HLT) have changed to some degree in the past 30 years, this treatment is being used less frequently in children due to more advanced care of severe heart and lung disease. This is fortunate as the outcomes for HLT are poor compared to other solid organ transplants and this is mainly due to the poorer outcome of the lung graft.

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.

Lung transplantation and pulmonary hypertension

The presence of pulmonary hypertension affects lung transplantation in multiple ways, from patient selection, transplant risks, type of transplant, intraoperative management, to transplant outcome. A working knowledge of natural disease progression, the latest medical treatment options, and transplant outcome is critical in patient selection, and a good understanding of the transplant process, including the new transplant allocation system, is important for physicians involved in the care of patients with pulmonary arterial hypertension. The complexity of these factors underscores the importance of good communication between referring physicians and transplant centers.

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.

Severe left ventricular failure after double lung transplantation: pathophysiology and management

Patients undergoing bilateral lung transplantation for end-stage pulmonary hypertension may experience various complications. We describe a patient who underwent transplantation for chronic pigeon breeder's disease, who had secondary pulmonary hypertension and deteriorated right heart function, and who developed severe left heart failure during the weaning phase after successful double lung transplantation. The patient was stabilized with catecholamines and an intra-aortic balloon pump. Left heart function increased within 7 days and normalized at Day 18. Otherwise, the post-operative course was uneventful.

Determination of prostacyclin in plasma through a bioluminescent immunoassay for 6-keto-prostaglandin F1alpha: implication of dosage in patients with primary pulmonary hypertension

This work describes a solid-phase immunoassay for 6-keto-prostaglandin F1alpha, the stable hydrolysis product of prostacyclin (prostaglandin I2). Prostacyclin, a potent vasodilator with antiplatelet and antiproliferative properties is an effective treatment for primary pulmonary hypertension and pulmonary arterial hypertension associated with scleroderma and scleroderma-like syndrome. Levels of 6-keto-prostaglandin F1alpha can be directly correlated with levels of prostacyclin. Therefore, 6-keto-prostaglandin F1alpha, has become the indicator of choice to measure prostacyclin levels. The single-step immunoassay for 6-keto-prostaglandin F1alpha reported here was developed using the bioluminescent protein aequorin as a label. Analyte-label conjugates were constructed by linking the carboxyl group of 6-keto-prostaglandin F1alpha and lysine residues of aequorin by chemical conjugation methods. The binding properties of 6-keto-prostaglandin F1alpha toward its antibody and the bioluminescent properties of aequorin were retained in the conjugate, which was then used to generate a dose-response curve for the analyte in a convenient microtiter plate format. The concentration of 6-keto-prostaglandin F1alpha after extraction from plasma showed good correlation with the concentration of 6-ketoprostaglandin F1alpha obtained without prior extraction of the same plasma sample. This measurement demonstrated that the assay allows the measurement of 6-keto-prostaglandin F1alpha directly in plasma without any pretreatment of the samples, which results in a much simpler method with a faster assay time.