A bilateral lung transplant quickly and effectively normalizes the right ventricular function of the heart in children with severe pulmonary arterial hypertension (PAH) and heart failure, according to a study.
These benefits in the 15 children evaluated were also independent of the child’s age, weight and right ventricular impairment (RV) prior to the transplant.
Given the observed recovery of cardiac function within two months of surgery, these findings support bilateral lung transplantation as a ‘preferred’ option over the more complex and difficult to obtain heart-lung transplant, even in patients. children with terminal PAH, the researchers noted.
The study, “Complete recovery of right ventricular systolic function in children undergoing bilateral lung transplantation for severe PAH, ”Was published in The Journal of Heart and Lung Transplantation.
The narrowing of the pulmonary artery characteristic of PAH restricts blood flow to the lungs, increasing blood pressure (hypertension) and causing the heart’s right ventricle to work harder to pump blood. Continued strain on the right ventricle can cause the walls of the RV to thicken, ultimately leading to heart failure.
As such, and despite recent improvements in treatment and patient survival, “bilateral (LuTx) or combined heart-lung-Tx (HLTx) lung transplantation remains the only established treatment option for patients with Terminal PAH, ”the researchers wrote.
However, the question of whether and how quickly RV function recovers after bilateral lung transplantation in children with severe PAH and heart failure remains largely unclear.
A team of researchers in Germany evaluated parameters related to VR in 15 children (12 girls and three boys) with severe PAH and LR failure who received bilateral lung transplantation.
The patients, aged 1.9 to 17.6 years, underwent the surgery at the Faculty of Medicine in Hanover between December 2013 and January 2021. Nine (60%) were under 12 years of age at the time of the surgery. .
Their heart health was assessed by advanced echocardiography (Echo) and cardiac MRI before surgery and approximately six weeks (1.5 months) after surgery. Cardiac MRI could not be performed in nine children, due to the need for general anesthesia or poor health.
Up to seven years of follow-up, all of the children were alive. They all showed “rapid and complete recovery” of RV systolic (contractile) function and significant reduction in RV wall thickening.
These benefits were seen regardless of age, weight, and severity of RV dysfunction prior to surgery.
In particular, the RV ejection fraction – the amount of blood pumped with each contraction – increased significantly from 30% to 63%, reflecting complete normalization of RV systolic function after lung transplantation.
Children also showed significant improvements in right ventricle-to-left ventricular telesystolic diameter ratios (VR / LV), a measure of abnormal RV widening and longitudinal RV contractility, assessed by both echo and MRI. .
However, the thickening of the right ventricle persisted beyond two months, as assessed by non-invasive imaging and the EKG.
Notably, the RV / LV telesystolic diameter ratios based on echo and MRI have been shown to be excellent diagnostic tools for assessing RV dysfunction, being superior to the systolic excursion of the tricuspid annular plane (TAPSE). . TAPSE is a commonly used echo measurement to assess systolic function of the right ventricle.
These results showed that “RV volumes and RV systolic function completely normalize” six weeks after bilateral lung transplantation, “even in children with severe RV insufficiency,” the researchers wrote.
Given the shortage of heart-lung block organs in North America and Europe, the greater surgical complexity of heart-lung transplantation, and the rapid recovery of RV function observed in this study, transplantation Bilateral pulmonary “should be preferred over heart-lung transplantation,” even in “end-stage pediatric PAH with poor right ventricular function and low cardiac output,” the team added.
In addition, “the easily accessible telesystolic RV / LV ratios and longitudinal 2D RV echocardiographic stress can likely follow the clinical improvement in pediatric PAH and may provide valuable prognostic information beyond LuTx, for example, response to pediatric PAH. complementary pharmacotherapy targeted at PAH ”, the researchers conclude.