Right top pulmonary vein is a venous anomaly of which surgeons should be aware in subcarinal dissection for thoracoscopic esophagectomy: a case report and literature review

Impact of Right Top Pulmonary Vein Location on Subcarinal Lymph Node Dissection in Thoracoscopic Esophagectomy: A Case Report and Literature Review

INTRODUCTION

The right top pulmonary vein (RTPV) is a rare anatomical variant that arises independently of the right superior lobe. It drains behind the right main bronchus or bronchus intermedius and into the left atrium or another pulmonary vein. This anomaly poses challenges during subcarinal lymph node dissection in thoracic surgery, such as esophagectomy, owing to the risk of vascular injury. The RTPV is mainly located behind the right main bronchus and right intermediate bronchus; however, reports of subcarinal dissection focusing on these sites are lacking. Herein, we present a case of esophageal cancer with an RTPV that was treated with thoracoscopic esophagectomy and propose a convenient classification for the anatomical findings and RTPV site.

CASE PRESENTATION

A 71-year-old man underwent a thoracoscopic esophagectomy for esophageal cancer (T1bN0M0) during a routine medical checkup. A preoperative computed tomography scan revealed an anomaly in which the RTPV drained into the left atrium behind the right main bronchus. Radical subcarinal lymphadenectomy was performed while preserving the RTPV, using 3 dimensions for preoperative simulation and intraoperative navigation. The operation lasted 6 h and 42 min, and the blood loss volume was 30 mL. The patient's postoperative course was uneventful, and he was discharged on postoperative day 21.

CONCLUSIONS

In a retrospective review of esophageal cancer surgery cases at our hospital, RTPV was observed in 17/314 cases (5.4%). The most common inflow site was the inferior pulmonary vein (IPV) (9 cases), followed by the left atrium (5 cases), superior pulmonary vein (2 cases), and superior branch of the IPV (1 case). The inflow site was behind the right main bronchus and the right intermediate bronchus in 4 and 13 cases, respectively. Compared to past reviews, the inflow site varied somewhat; however, the vascular location remained the same. By classifying the areas behind the right main and right intermediate bronchi as Zones 1 and 2, respectively, cases in which the RTPV runs through Zone 1, as identified on preoperative computed tomography, should be manipulated with caution due to the risk of injury during lymph node dissection beneath the tracheal bifurcation.

Intraoperative Fluorescent Imaging with Indocyanine Green during Thoracoscopic Esophagectomy with Subcarinal Lymph Node Dissection for Esophageal Cancer with a Right Superior Pulmonary Vein Anomaly: A Case Report and Literature Review

A 68-year-old woman was diagnosed with clinical T3N1M0 middle thoracic esophageal cancer. Preoperative three-dimensional computed tomography indicated a right superior posterior pulmonary vein (RSPPV) anomaly, which ran behind the right intermediate bronchus. The patient underwent thoracoscopic esophagectomy with mediastinal lymph node (LN) dissection. Before we began the dissection of the right subcarinal LN, we administered indocyanine green intravenously to confirm the running position of the anomalous RSPPV, and we were able to ascertain its placement accurately with correct recognition of the difference between the blood vessels and surrounding tissue. Although the patient had LN metastasis adjacent to this anomalous vessel and the dissection procedure was tough due to tightly adhesion, intraoperative fluorescent imaging enabled us to perform the dissection without any superfluous vascular injury. Intraoperative fluorescent imaging is very useful in such cases, providing accurate intraoperative information on the location of the anomaly and facilitating safer surgery.

Clinically important pulmonary vascular variations: a narrative review

Background and Objective

Pulmonary vascular variations are a major factor in thoracic surgeries. Minimally invasive techniques, such as video-assisted thoracic surgery (VATS) used in non-small lung cancer treatment, have a limited field of view and no haptic feedback. Additionally, new studies suggest that segmentectomies are beneficial for patients. Accurate knowledge of vascular patterns and variants is crucial for conducting such procedures safely. The aim of this review was to systematize data in a useful manner from studies and case reports concerning pulmonary vascular variations and patterns.

Methods

We conducted a search on the PubMed and Embase databases. We used classifications of Nagashima, Yamashita, Boyden, Maciejewski, and Shimizu.

Key Content and Findings

The analysis showed that more data on the incidence rate and vascular patterns of certain bronchopulmonary segments are needed. Venous variations are a major factor in segmental resections, but additional data regarding incidence and pattern types are needed. Surgeons need to be aware of vascular variations as they can influence procedures in seemingly unrelated areas. The majority of studies emphasize the use of three-dimensional (3D) reconstruction of computed tomography (CT) for accurate planning of any thoracic procedures.

Conclusions

Abnormal vessels pose a risk in various procedures performed within the thorax, and the data in this review could be valuable in different medical areas in this regard.

Catheter ablation of the left-sided variant of right top pulmonary vein in a case with persistent left superior vena cava

A 50-year-old woman underwent catheter ablation for atrial fibrillation. Preoperative computed tomography revealed a left-sided variant of the right top pulmonary vein (PV) and a persistent left superior vena cava. The right top PV was successfully isolated through a wide antral circumferential ablation line simultaneously with the right PVs.

Thoracoscopic esophagectomy with subcarinal lymph node dissection in the prone position for esophageal cancer with a right top pulmonary vein

The right top pulmonary vein (RTPV), a rare pulmonary vein (PV) variant draining the right upper lobe, arises independently from the right superior PV, travels posterior to the right bronchial tree and drains directly into the left atrium (LA) or another PV. We report an RTPV discovered on preoperative computed tomography (CT) scanning in a 60-y-old man who subsequently underwent prone thoracoscopic esophagectomy and subcarinal lymph node dissection. The preoperative CT scan showed an anomalous vessel 7.8 mm in diameter arising from the right upper lobe, running posterior to the right main bronchus (RMB), and draining directly into the LA. To our best knowledge, this is the largest reported RTPV (7.8 mm in diameter) and is an extremely rare variant, passing posterior to the RMB and draining into the LA.