Mechanical Circulatory Support as a Bridge to Transplantation
A 48-year-old male with previous history of leukemia now in remission presented to Temple University Hospital as an emergent evaluation for lung transplantation. He had been diagnosed with idiopathic pulmonary fibrosis several months prior and managed with oxygen and an anti-fibrotic medication. He then presented to an outside hospital for progressive shortness of breath and was treated with antibiotics for presumed pneumonia; when cultures were negative he was treated with high-dose steroids. Despite this, his course progressed and he warranted 100 percent oxygen, at which time he was referred to the Temple Lung Center for advanced pulmonary management options and possible lung transplantation.
Diagnostic Findings Upon Arrival at Temple
• ECHO: Left ventricle ejection fraction 60–65%, right ventricle (RV) moderately to markedly dilated with reduced systolic function. TAPSE 12mm, estimated RV systolic pressure 88mmHg.
• Cardiac catheterization:
• Right heart catheterization: (systolic/diastolic/mean) pulmonary artery pressure 105/42/58; pulmonary capillary wedge pressure 31/33/32; right atrial pressure 24/33/16; right ventricular pressure 81/17
• Left heart catheterization: Coronary circulation minor luminal irregularities, non-obstructive coronary artery disease
• Arterial blood gas done on 100% FiO2 via 40L high-flow nasal cannula: PH 7.47 PCO2 38 PO2 106 HCO3 27
• Also performed CXR and high-resolution chest CT
After diagnostic testing, a multidisciplinary conference discussed and approved the patient’s listing for transplantation. While waiting for suitable donor lungs, the patient’s clinical course worsened and he was placed on extracorporeal membrane oxygenation (ECMO). Given the patient’s extensive requirements for oxygen and RV dysfunction, his ECMO device was upgraded to a right ventricular assist device (RVAD) with an oxygenator meet his increasing oxygen demands while supporting his RV. He remained on the RVAD device nearly a month waiting for suitable donor lungs, and it allowed him to not only remain off mechanical ventilation but also to participate in regular physical therapy.
He received a successful uncomplicated double-lung transplant nearly 45 days after his initial presentation to TUH. His post-operative course remained largely uncomplicated and, with aggressive physical therapy on our lung transplant recovery floor, he was safely discharged home two weeks after his transplant surgery. He has remained out of the hospital, off oxygen and bike riding daily, nearly a year after his transplant.
The prognosis of fibrotic lung disease is poor and the clinical course can be one of rapid decline or of slow steady progression. When a patient is diagnosed with this disease, a referral to a lung transplant center is appropriate. With the advent of advanced circulatory devices like ECMO, a patient who otherwise would have perished may now survive long enough to complete a transplant evaluation and find a suitable donor.
• Progressive fibrotic lung disease warrants early referral for lung transplantation.
• Salvage devices, e.g. ECMO, can provide a bridge to transplantation in carefully selected patients who would otherwise not survive waitlist times.
• Circulatory devices, when employed in high-volume ECMO centers, allow patients to ambulate and maintain strength to provide optimal post-transplant outcomes.
• High-volume transplant centers like the Temple Lung Center pursue innovative techniques and devices to optimize patient outcomes.
Patrick Mulhall, MD Assistant Professor, Thoracic Medicine and Surgery
Lewis Katz School of Medicine at Temple University