Introduction
As life expectancy increases for patients who undergo Fontan palliation, a growing number require intervention for non-cardiac pathology. There is a paucity of literature on managing these patients, especially for high-risk non-cardiac surgery. The standard of care for early-stage lung adenocarcinoma is surgical resection. However, patients with Fontan circulation pose a unique challenge to the oncologic treatment algorithm due to factors such as impaired cardiac output, passive pulmonary blood flow, which is reliant on low pulmonary vascular resistance, arterio-venous and veno-venous collaterals, and lymphatic malformations. Here, we present our management of a patient with tricuspid atresia status post Fontan palliation with a Stage Ib lung adenocarcinoma and ask the readers to consider their programme’s approach to this rare clinical scenario.
Clinical summary
A 29-year-old male with a past medical history of tricuspid atresia presented for new onset fatigue due to the loss of pacing from a fractured atrial lead. He was palliated with a lateral tunnel Fontan and had an epicardial pacemaker system for sinus node dysfunction. He had normal systolic function on transthoracic echocardiography, and recent cardiac catheterisation demonstrated a mean Fontan pressure of 13 mmHg and normal pulmonary vascular resistance. He is ACHD-AP class IIIC with mild Fontan-associated liver disease (stage F1 fibrosis). In anticipation of a sixth sternotomy for atrial lead replacement, he underwent preoperative chest X-ray and CT of the chest and was incidentally found to have a 2.5 cm right upper lobe mass (Figure 1). The mass was fluorodeoxyglucose-avid and biopsy-proven lung adenocarcinoma with no evidence of nodal or metastatic disease (T2a N0 M0—Stage 1b). Pulmonary function tests showed an FEV1/FVC ratio of 78% and a diffusing capacity of lungs for carbon monoxide of 73% predicted.
Coronal slice from computed tomography of the chest demonstrating a 2.5 cm mass in the right upper lobe, which was FDG-avid and biopsy-proven adenocarcinoma.
In light of the newly diagnosed malignancy, he underwent leadless atrial pacemaker implantation. Multidisciplinary discussion recommended external beam radiation as definitive treatment.
Discussion
Improved outcomes of single-ventricle palliation have resulted in a large worldwide population of adults with a Fontan circulation. Interventions for non-cardiac pathology require careful consideration of the manifestations of nonpulsatile pulmonary blood flow. Changes in pulmonary vascular resistance, reductions in the total available pulmonary vascular bed, hypoxia, hypercarbia, hypotension, arrhythmias, and postoperative adhesions represent some of the potential risks for these patients. Reference Egbe, Khan and Ammash1,Reference Majima, Kagawa, Suzuki and Kurosaki2 Lung cancer susceptibility in palliated single-ventricle patients may be a function of cumulative ionising radiation from diagnostic and interventional procedures, genetic abnormalities, Fontan-associated liver diseases, and chronic hypoxia. Reference Takechi, Kawasoe, Tateno, Ebata, Hamada and Niwa3,Reference Cohen, Liu and Gurvitz4,Reference Cohen, Gurvitz, Beauséjour-Ladouceur, Lawler, Therrien and Marelli5 In addition to these, our patient had a significant family history of malignancy. The standard approach to Stage Ib adenocarcinoma of the lung with adequate pulmonary function testing is surgical resection. Nagayama and colleagues reported a successful left upper lobectomy for a T2N0M0 adenocarcinoma in a 26-year-old man with Fontan circulation. Reference Nagayama, Kitano, Yoshiyasu and Nakajima6 Of note, the patient in that report had only 10% perfusion to the left lung. Successful single lung ventilation has been reported for other intrathoracic procedures as well, with particular emphasis on the maintenance of low pulmonary vascular resistance and adequate cardiac output, as well as strategies to avoid hypercarbia and acidosis. Reference Sasaki, Kato and Minoshima7,Reference Cvetkovic, Ramzy, Vitale, Malekan and Warsy8
This case highlights what is likely to become a more prevalent scenario—an adult Fontan patient who requires a non-cardiac intervention. Our multidisciplinary discussion attempted to make a recommendation based on limited evidence. We concluded that although this patient was a “good” Fontan, the lower immediate mortality risk would be acceptable at the expense of potentially worse long-term oncologic outcome, with the critical caveat that radiation would not preclude future lung resection in case of persistent/recurrent disease. There is limited data suggesting radiation can cause dose-dependent vascular changes through endothelial cell loss, impaired vasodilation, inflammation, and inhibited angiogenesis, resulting in increased pulmonary vascular resistance. Reference Ghobadi, Bartelds and Van Der Veen9 In light of the limited radiation field, we considered that this risk may not significantly impact the patient’s hemodynamics and surgical candidacy. We present this case to the readership both for its rarity but also to pose the question “What would you do?”
Financial support
This research received no specific grant from any funding agency, commercial, or not-for-profit sectors.
Competing interests
None.
Ethical standards
Our institution does not require ethical approval for individual case reports. The authors thank the patient for granting permission to publish this case.
