Lung Transplantation on Cardiopulmonary Bypass: Time Matters

Regression of Tricuspid Valve Regurgitation After Lung Transplant: A Single-Center Experience

BACKGROUND

Although tricuspid regurgitation (TR) is common in candidates for lung transplant, no data or established guidelines exist regarding the need for surgical repair at the time of transplant. We aimed to evaluate the natural course of TR by assessing the incidence and extent of TR regression among patients who did not undergo tricuspid valve repair (TVR) concomitantly with lung transplant.

METHODS

We retrospectively identified adult patients who underwent lung transplant without TVR at our institution from 2001 through 2017. Pretransplant and posttransplant echocardiograms were reviewed to assess severity of TR, tricuspid annular plane systolic excursion, central venous pressure, mean pulmonary arterial pressure, and right ventricular size and function.

RESULTS

Among 553 included patients, 324 (58.7%) were men, the mean (SD) age was 61.9 years (12.7), and 417 (75.4%) had a double lung transplant. TR before transplant was reported as trivial in 265 patients (47.9%), mild in 235 (42.5%), moderate in 40 (7.2%), and severe in 13 (2.4%). After transplant, TR improved significantly overall (P < .001). TR improved in 193 patients: 158 patients (81.9%) by 1 grade and 35 patients (18.1%) by 2 or more grades. Additionally, of 53 patients with pretransplant moderate or severe TR, 44 (83%) had improvement to mild, trivial, or no TR. After transplant, 12 patients (2.2%) had no remaining TR.

CONCLUSION

The severity of TR improved or showed no change in most patients after lung transplant, which obviates the need for TVR among most lung transplant recipients.

Evolution of Recipient Characteristics Over 3 Decades and Impact on Survival After Lung Transplantation

BACKGROUND

Lung transplantation (LTx) is a definitive treatment for end-stage lung disease. Herein, we reviewed our center experience over three decades to examine the evolution of recipient characteristics and contemporary predictors of survival for LTx.

METHODS

We retrospectively reviewed the data of LTx procedures performed at our institution from 1/1990 to 1/2019 (n=1819). The cohort is divided into three eras; I: 1990-1998 (n=152), II: 1999-2008 (n=521), III: 2009-2018 (n=1146). Uni- and multivariate analyses of survival in era III were performed.

RESULTS

Pulmonary fibrosis has become the leading indication for LTx (13% in Era I, 57% in Era III). Median recipient age increased (Era I: 46 years - Era III: 61 years) as well as intraoperative mechanical circulatory support (Era I: 0% - Era III: 6%). Higher lung allocation score (LAS) was associated with primary graft dysfunction (PGD) (p<0.0001), postoperative ECMO (p<0.0001), and in-hospital mortality (p=0.002). In Era III, hypoalbuminemia, thrombocytopenia, and high PGD grade were multivariate predictors of early mortality. The 5-year survival in Era II (55%) and III (55%) were superior to Era I (40%, p<0.001). Risk factors for late mortality in era III included recipient age, chronic allograft dysfunction, renal dysfunction, high MELD score, and single LTx.

CONCLUSIONS

In this longitudinal single-center study, recipient characteristics have evolved to include sicker patients with greater complexity of procedures and risk for postoperative complications but without significant impact on hospital mortality or long-term survival. With advancing surgical techniques and perioperative management, there is room for further progress in the field.Supplemental Visual Abstract; http://links.lww.com/TP/C191.

Comparison of mechanical cardiopulmonary support strategies during lung transplantation

INTRODUCTION

Lung transplantation outcomes are influenced by the intraoperative mechanical cardiopulmonary support strategy used. This surgery was historically done either on cardiopulmonary bypass (CPB) or off pump. Recently, there has been increased interest in intraoperative support with veno-arterial (VA) or veno-venous (VV) extracorporeal membrane oxygenation (ECMO). However, there is a lack of consensus on the relative risks, benefits and indications for each intraoperative support strategy.

AREAS COVERED

This review includes information from cohort studies, case-control studies, and case series that compare morbidity and/or mortality of two or more intraoperative cardiopulmonary support strategies during lung transplantation.

EXPERT OPINION

The optimal strategy for intraoperative cardiopulmonary support during lung transplantation remains an area of debate. Current data suggest that off pump is associated with better outcomes and could be considered whenever feasible. ECMO is generally associated with preferable outcomes to CPB, but the data supporting this association is not robust. Interestingly, whether CPB is unplanned or prolonged might influence outcomes more than the use of CPB itself. These observations can help guide surgical teams in their approach for intraoperative mechanical support strategy during lung transplantation and should serve as the basis for further investigations.