Right Pneumonectomy for Right Lower Lobe Lung Cancer with Partial Anomalous Pulmonary Venous Connection in Another Ipsilateral Lobe: A Case Report

Partial anomalous pulmonary venous connections (PAPVC) are rare. We report a case of right pneumonectomy for right lower lobe lung cancer, wherein a PAPVC was detected in the right upper lobe vein before surgery.

A 71-year-old man was diagnosed with a mass in the right lower lobe on chest CT. Non-small-cell lung cancer was diagnosed using bronchoscopy. Right bilobectomy (middle and lower lobes) was planned to secure a margin for resection due to hypoplasia of the middle lobe; however, preoperative contrast-enhanced CT revealed a PAPVC involving the right upper lobe. If a PAPVC is identified in a non-resected lung lobe, the patient is at risk of postoperative right heart failure. In cases of PAPVC in a non-resected lobe with Qp/Qs ≥1.5, preoperative or intraoperative revascularization is recommended. Echocardiography demonstrated a pulmonary to systemic flow ratio (Qp/Qs) of 1.39; however, right heart catheterization showed an increase in Qp/Qs to 1.66. Therefore, we considered repairing the right upper pulmonary vein. However, owing to the unstable position of the right upper lobe and the length of the repaired vessel, we performed a right pneumonectomy considering the risk of vascular flexion and occlusion. The postoperative course was uneventful, and echocardiography performed 3 months after the procedure revealed an ejection fraction of 57%.

In the present case, by assessing Qp/Qs using both echocardiography and right heart catheterization, we determined an appropriate surgical approach. However, right pneumonectomy is a risk factor for right-sided heart failure, and limited resection or nonsurgical treatment should be considered in certain cases. The presence of PAPVC in a non-resected lung requires caution when selecting the surgical approach. In cases of PAPVC, detailed preoperative CT evaluation is essential.