Discussion
Over the past 20 years, the number of HLTx has been decreasing from 145 in 1999 to 45 in 2019 and gradually replaced with bilateral lung transplant (BLTx).4 It has been an ongoing debate on whether to perform HLTs or BLTx for patients with PH.5HLTx is recommended to patients with congenital heart disease and Eisenminger syndrome, severe right ventricular (RV) dysfunction, and severe left ventricular dysfunction. On the other hand, BLTx provides comparable outcomes, moreover, it offers the advantage of better organ sharing. Given the long waiting time, patients with PH and simple cardiac anomalies such as atrial septal defect, patent ductus arteriosus or perimembranous ventricular septal defect can be successfully managed with a combination of BLTx and cardiac repair. The cut-off values for BLTx can be approximated at 10-25% RVEF and 32-55% LVEF. For values less than this cut-off, HLTx is recommended.5
We are reporting a successful HLTx in a patient with cc-TGA and dextrocardia. Our patient was presented with advanced cardiac problems including severe PH, severe systemic and sub-pulmonary atrioventricular valves regurgitation, complete heart block and biventricular failure. In our patient, the RV was the systemic ventricle and its failure attributed to the severely incompetent systemic valve and the afterload systemic pressure. Hence, BLTx will not improve the condition of the failing systemic RV and the HLTx was deemed the suitable option. Based on the aforementioned findings, the multidisciplinary team recommended HLTx procedure. HLTx is technically a well-established surgical procedure, however, our case demonstrated unique surgical challenges due to the complexity of the congenital cardiac anomaly (cc-TGA and dextrocardia) of the recipient. The combination of the cc-TGA and dextrocardia is extremely rare. To the best of our knowledge, only one case of cc-TGA and dextrocardia has been reported by Takemoto et al. in the literature which was managed medically (i.e. no HLTx).6 This combination posed challenges for both the surgeon and anesthesiologist during the preoperative preparation and during the transplant procedure. The strategy of the approach, cannulation, and the technique was quite different from the standard HLTx. Giving the fact that both the superior and inferior vena cava were presented posteriorly, venous cannulation was initiated via dual stage venous cannula placed in the right atrium transitioned to bi-caval configuration after decompressing the heart.
According to the 2016 ISHLT report included the data of patients underwent HLTx in 2004–2014, the survival rates at 1, 2, 5, and 10 years are 63%, 52%, 45%, and 32%, respectively, and a median survival of 5.8 years.7 As of today, 15 months postoperatively, the patient is doing well.