Abnormal branching of the left lingular pulmonary artery diagnosed by three-dimensional computed tomographic angiography in a patient with lung cancer: a case report

Aberrant mediastinal basal pulmonary artery encountered at anatomical lung resection: A case report and review of the literature

INTRODUCTION

Abnormal branching of the pulmonary artery is often encountered in anatomical lung resection, which can potentially result in accidental vessel injury with life-threatening bleeding or extra lung resection. The mediastinal basal pulmonary artery (Arteria Praebronchialis, AP) is a very rare but potentially critical variant.

PRESENTATION OF CASE

We present the case of a patient with lung cancer accompanied by the left basal segmental pulmonary artery, independent A8a+9, which was liable to be injured during lower lobectomy with poor interlobar fissure development. This variation was preoperatively recognized using three-dimensional contrast-enhanced computed tomography (3D-CECT) angiography, and vessel injury was avoided.

DISCUSSION AND LITERATURE REVIEW

3D-CECT angiography was effective in identifying this rare but potentially critical variation, and it is desirable to perform it routinely before anatomical lung resection. A review of 31 AP cases revealed that the branching pattern of AP was independent (15 patients, 48 %) and common trunk type (16 patients, 52 %), one half for each. Mediastinal branching of the lingular artery was more frequent among the reported AP cases (71 %) than in general reports.

CONCLUSION

When mediastinal branches of left pulmonary artery are encountered, the possibility that it is AP should be always taken into account.

Arteria Praebronchialis (AP) Found on MDCT: An Updated Incidence and Branching Patterns

Preoperative detection of the arteria praebronchialis (AP), a rare variant mediastinal branch of the left pulmonary artery, can be crucial to a successful left-lung surgery; if the AP is overlooked and ligated during surgery, the blood supply to the remaining lobe may be compromised. The purpose of this study was to update the incidence and branching patterns of the AP. From 18 April 2012 to 31 December 2022, contrast-enhanced CT was screened by one radiologist for the presence of AP. Branching patterns of the AP were analyzed by three thoracic radiologists. The incidence of AP was updated to 0.068% (18/26,310) from the previously reported 0.03%; the incidence of AP for male and female patients was 0.110% and 0.017%, respectively. AP supplied only the LLL in 10 cases and both the lingular division of LUL and LLL in nine cases. Dual segmental supply by both the AP and the normal left descending pulmonary artery existed in 15 cases; exclusive segmental supply by either artery existed in four cases. The AP supplies either the LLL alone or both LLL and the lingular division of LUL, and its incidence is not negligible in the male population, necessitating routine surveillance prior to pulmonary resection.

Mediastinal basal pulmonary artery identification and classification by three-dimensional reconstruction

PURPOSE

The primary objective of the present study was to use CT angiography and 3D reconstruction to assess and to classify the mediastinal pulmonary basal segmental arteries.

METHODS

We report a particular type of bifurcated left lower pulmonary artery, namely, the "mediastinal basal pulmonary artery" type, which is the first branch from the proximal the left pulmonary artery (LPA) between the left main bronchus (LMB) and the left superior pulmonary vein (LSPV) and proceeding directly into the lower lobe. There are many types of mediastinal basal pulmonary arteries, and these can be classified worldwide in a unified way and format, which will be beneficial for clinical records, annotation and academic exchange.

RESULTS

The mediastinal basal pulmonary arteries are described either as "supernumerary" when duplicating or "displaced" when replacing the normal arterial branching pattern of the lower lobe. The displaced type is more frequent than the supernumerary type. There are 12 types of left mediastinal basilar arteries.

CONCLUSION

This is the first report to categorize the mediastinal basal pulmonary artery, is the first to suggest a system for mediastinal basal pulmonary artery nomenclature, and creates simplified models for use when planning anatomical segmentectomy. Knowledge and recognition of this rare and special condition may facilitate better diagnosis and treatment of these patients.

Variations in the branching patterns of pulmonary artery during thoracoscopic pulmonary resection

PURPOSE

The knowledge of variations in the branching patterns of pulmonary artery may have important clinical implications in the field of thoracic surgery.

METHODS

At the Department of Thoracic Surgery of Monaldi Hospital in Naples, between January 2017 and December 2019, 569 anatomic pulmonary resections via video-assisted thoracic surgery, including lobectomy and segmentectomy, were performed.

RESULTS

Among the 569 thoracoscopic pulmonary resections, 24 variations in the branching patterns of pulmonary artery were identified and documented. Anatomic variations on the left were more frequent than on the right.

CONCLUSION

This paper, providing a summary of vascular anomalies identified during major lung resections, could help surgeons avoid intraoperative complications, especially during minimally invasive procedures where the visual field is more restricted than open surgery.

Intraoperative diagnosis with abnormal branching of the left A8 pulmonary artery from the left main pulmonary artery

BACKGROUND

Safety is of vital importance for lung resection. The dissection of pulmonary vessels is associated with vascular injury and bleeding, and identification of the vessels is necessary. The most common abnormal branching pattern of the left pulmonary artery is the mediastinal lingular artery. However, a mediastinal basal pulmonary artery is very rare. A case of abnormal branching from the left pulmonary artery to S8 which was diagnosed intraoperatively, and, thus, its dissection was avoided, is reported.

CASE PRESENTATION

A 76-year-old woman with rheumatoid arthritis was diagnosed with left upper lung adenocarcinoma and visited our hospital. Contrast CT was not performed due to renal dysfunction, and abnormal branching of the left pulmonary artery was not identified. Video-assisted thoracoscopic left upper lobectomy and lymphadenectomy were performed. After the upper pulmonary vein was dissected and tissue around it was detached carefully, a pulmonary mediastinal branch from the left main pulmonary artery was identified descending between the upper pulmonary vein and upper bronchus. It was possible to separate the interlobar fissure safely and preserve A8. On retrospective examination, non-contrast CT showed A8.

CONCLUSIONS

Although preoperative identification of left pulmonary mediastinal branches was difficult by non-contrast CT, a careful surgical procedure preserved the left pulmonary mediastinal A8.

Composite resection of the left upper lobe and superior segment (S6) of the lower lobe for lung cancer with a mediastinal lingular and basal pulmonary artery

Background

Preoperative evaluation and awareness of anatomical variations in the pulmonary vessel is essential for a secure pulmonary resection. We herein present a patient who underwent complex pulmonary resection for lung cancer with a mediastinal lingular and basal pulmonary artery that had been detected by preoperative three-dimensional computed tomography.

Case presentation

The patient was an asymptomatic 66-year-old woman who had a 39-pack-year smoking habit. Chest computed tomography (CT) revealed the tumor invading the left upper bronchus and pulmonary artery branches in the left upper lung lobe. Enhanced CT and three-dimensional (3D) images of the pulmonary artery revealed that pulmonary artery branches (A4 + 5, A8, and A9 + 10) were extending into the lingular and basal segment in ventral side of the left upper bronchus. We completed the resection by means of a composite resection of the left upper lobe and the superior segment of the lower lobe, avoiding pulmonary angioplasty to preserve the left lower lobe or pneumonectomy.

Conclusions

3D-CT is useful for detecting this rare variation of the left pulmonary artery before operation, allowing for proper resection.

Electronic supplementary material

The online version of this article (10.1186/s40792-018-0445-0) contains supplementary material, which is available to authorized users.