Postpneumonectomy Pulmonary Artery Stump Thrombosis: CT Features and Imaging Follow-up

The pulmonary-vascular-stump filling defect on CT post lung tumor resection: a predictor of cancer progression

BACKGROUND

To explore the pulmonary-vascular-stump filling-defect on CT and investigate its association with cancer progression.

METHODS

Records in our institutional database from 2018 to 2022 were retrospectively analyzed to identify filling-defects in the pulmonary-vascular-stump after lung cancer resection and collect imaging and clinical data of patients.

RESULTS

Among the 1714 patients analyzed, 95 cases of filling-defects in the vascular stump after lung cancer resection were identified. After excluding lost-to-follow-up cases, a total of 77 cases were included in the final study. Morphologically, the filling-defects were dichotomized as 46 convex-shape and 31 concave-shape cases. Concave defects exhibited a higher incidence of increase compared to convex defects (51.7% v. 9.4%, P = 0.001). Among 61 filling defects in the pulmonary arterial stump, four (6.5%) increasing concave defects showed the nuclide concentration on PET and extravascular extension. The progression-free survival (PFS) time differed significantly among the concave, convex, and non-filling-defect groups (log-rank P < 0.0001), with concave defects having the shortest survival time. Multivariate Cox proportional hazards analysis indicated that the shape of filling-defects independently predicted PFS in early onset on CT (HR: 0.46; 95% CI: 0.39-1.99; P = 0.04). In follow-ups, the growth of filling-effects was an independent predictor of PFS (HR: 0.26; 95% CI: 0.11-0.65; P = 0.004).

CONCLUSIONS

Certain filling-defects in the pulmonary-arterial-stump post lung tumor resection exhibit malignant growth. In the early onset of filling-defects on CT, the concave-shape independently predicted cancer-progression, while during the subsequent follow-up, the growth of filling-defects could be used independently to forecast cancer-progression.

Imaging findings of the postoperative chest: What the radiologist should know

Thoracic surgical procedures are increasing in recent years, and there are different types of lung resections. Postsurgical complications vary depending on the type of resection and the time elapsed, with imaging techniques being key in the postoperative follow-up. Multidisciplinary management of these patients throughout the perioperative period is essential to ensure an optimal surgical outcome. This pictorial review will review the different thoracic surgical techniques, normal postoperative findings and postsurgical complications.

Clinical characteristics and course of pulmonary artery stump thrombosis following lung cancer surgery: A retrospective study from tertiary care hospital

The data regarding pulmonary artery stump thrombosis (PAST) after lung cancer surgery are insufficient. The aim of the present study was to evaluate the incidence, clinical characteristics, and prognosis of PAST. We retrospectively investigated the incidence and clinical characteristics of PAST among patients who underwent lung resection for lung cancer at 2 institutions. We compared the clinical parameters between PAST and pulmonary embolism (PE) and examined the clinical course of patients with PAST. Of the 1885 patients, PAST was found in 36 patients (1.9%). Right lower lobectomy (n = 13) and middle-lower bilobectomy (n = 9) were the most common types of surgery. The median time interval from lung resection to the detection of PAST was 3.8 months. Immobilization and a history of cerebrovascular disease were not observed in the PAST group. Most of the patients with PAST (91.7%) were diagnosed incidentally, whereas many patients with PE (75.9%) were symptomatic at the time of diagnosis. During the follow-up, one patient (2.8%) had contralateral PE complications. However, no patients in the PAST group experienced pulmonary thromboembolism-related in-hospital death or adverse outcomes. There was no difference in the prognosis of patients with PAST according to the administration of anticoagulation. PAST was rarely detected in lung cancer patients on follow-up chest computed tomography after lung resection. Patients with PAST were asymptomatic in most cases and had relatively favorable clinical outcomes. However, these patients are at risk of contralateral PE, despite its rarity.

Isolated pulmonary embolism - a specific clinical entity?

Pulmonary embolism in classical meaning is a complication of deep vein thrombosis (usually in the leg veins), developing after a part of the thrombus dislodged and got wedged in pulmonary arteries. However, in half of the patients with pulmonary embolism, deep vein thrombosis is not found. One potential explanation is a different, less common location of the thrombus or previous complete embolization of the whole thrombotic mass. Another possibility is pulmonary artery thrombosis in situ, which is a specific clinical entity associated with some typical risk factors. It develops in the place of vascular injury, as a consequence of hypoxia, inflammatory changes, endothelial dysfunction and injury. Pulmonary artery thrombosis in situ can be a complication after lung resection, radiation therapy, chest trauma, in the patients with Behçet´s disease, sickle cell anemia, chronic obstructive pulmonary disease, tuberculosis or covid pneumonia. Pulmonary artery thrombosis in situ may differ from classical pulmonary embolism in prognosis as well as in therapeutic approach.

Pitfalls in the imaging of pulmonary embolism

Pulmonary embolism (PE) can present with a wide spectrum of clinical symptoms that can overlap considerably with other cardiovascular diseases. To avoid PE related morbidity and mortality, it is vital to identify this disease accurately and in a timely fashion. Several clinical criteria have been developed to standardize the diagnostic approach for patients with suspected PE. Computed tomographic pulmonary angiogram has significantly improved the detection of pulmonary embolism and is considered the imaging modality of choice to diagnose this disease. However, there are several potential pitfalls associated with this modality which can make diagnosis of PE challenging. In this review, we will discuss various pitfalls routinely encountered in the diagnostic work up of patients with suspected PE, approaches to mitigate these pitfalls and incidental pulmonary embolism.

Frequency and Predictors of Pulmonary Arterial Stump Thrombosis following Pneumonectomy or Lobectomy

OBJECTIVES

Pulmonary artery stump thrombosis (PAST) following pneumonectomies/lobectomies is rare; its clinical importance is unknown. The objectives of this study were to analyze the prevalence and risk factors of PAST and the clinical significance in patients with pneumonectomy/lobectomy.

METHODS

All adult cases who underwent pneumonectomy/lobectomy in our hospital for any reason and who underwent control contrast-enhanced thoracic CT during the follow-up period were included in the study. Demographic and clinical features of the patients, data on surgery, and the features of thrombi were recorded.

RESULTS

During the 4-year study period, a total of 454 patients underwent pneumonectomy/lobectomy (93 pneumonectomy and 361 lobectomy). Among the patients, 202 patients (50 pneumonectomy and 152 lobectomy) with at least one follow-up thorax CT were included in the analyses. PAST was detected in 9 (4.5%) of 202 patients and mostly seen in patients with pneumonectomy (lobectomy: 2.6% vs. pneumonectomy: 10%, p = 0.043) and in patients whose pulmonary artery was ligated by using stapler (suture ligation 1% vs. stapler: 7.4%, p = 0.034). Pulmonary artery stump was also longer in patients with PAST (8.48 ± 11.22 mm vs. 23.55 ± 11.22 mm, p < 0.001). Univariate logistic regression analysis showed that pneumonectomy and longer pulmonary artery stump length were found to be significantly associated with PAST (p = 0.041 and p = 0.001, respectively).

CONCLUSIONS

PAST was detected in 4.5% of our subjects undergoing lobectomy/pneumonectomy. PAST was found to be significantly higher in subjects who underwent pneumonectomy, those with longer pulmonary artery stump, and those with pulmonary artery stump ligated by using stapler.

Pearls and Pitfalls in Postsurgical Imaging of the Chest

A variety of surgical procedures are utilized to treat a spectrum of cardiopulmonary diseases. In the imaging of patients in the post-operative period, it is important to have an understanding of surgical techniques including invasive and minimally invasive procedures and the expected postsurgical findings. Knowledge of certain patient risk factors, various complications associated with specific surgical procedures, and a keen attention to detail are essential to avoid misinterpretation and delay diagnosis. Prompt detection of potential complications allows timely intervention, thereby, optimizing patient outcomes in the post-operative period.

Pulmonary Artery Stump Thrombosis: To Treat or Not to Treat? The Question Is Still Open. Description of a Case and Review of the Literature

Pulmonary artery stump thrombosis (PAST) represents a possible complication after lung surgery. We report the case of a 59-year-old man who presented with dyspnoea about 4 years after right pneumonectomy due to squamous cell lung cancer. A CT-scan showed the presence of pulmonary artery stump thrombosis. Although there was no evidence of pulmonary embolism, given the clinical features and radiological shape of the thrombus, anticoagulation treatment with low-molecular-weight heparin was started with improvement of symptoms. The patient was discharged on anticoagulant treatment and a pulmonary CT-scan performed 4 months later showed an almost complete resolution of the PAST. Pathophysiological mechanisms of PAST are still unknown, although several hypotheses have been proposed. However, the decision to treat PAST with anticoagulants is still controversial. A review of literature will be provided in order to discuss risk factors, possible etiologies and to highlight clinical and radiological characteristics that could suggest to treat this condition, in particular when there is an increased risk of complications.

In situ Pulmonary Artery Thrombosis: A Previously Overlooked Disease

Pulmonary thromboembolism (PTE) is the third leading cause of death in cardiovascular diseases. PTE is believed to be caused by thrombi detached from deep veins of lower extremities. The thrombi travel with systemic circulation to the lung and block pulmonary arteries, leading to sudden disruption of hemodynamics and blood gas exchange. However, this concept has recently been challenged by accumulating evidence demonstrating that de novo thrombosis may be formed in pulmonary arteries without deep venous thrombosis. On the other hand, chronic thromboembolic pulmonary hypertension (CTEPH), a subtype of pulmonary hypertension, could have different pathogenesis than traditional PTE. Therefore, this article summarized and compared the risk factors, the common and specific pathogenic mechanisms underlying PTE, in situ pulmonary artery thrombosis, and CTEPH at molecular and cellular levels, and suggested the therapeutic strategies to these diseases, aiming to facilitate understanding of pathogenesis, differential diagnosis, and precision therapeutics of the three pulmonary artery thrombotic diseases.

The postoperative chest in lung cancer

Most of the complications following lung cancer surgery occur in the early postoperative period and can result in significant morbidity and mortality. Delayed complications can also occur. Diagnosing these complications can be challenging because clinical manifestations are non-specific. Imaging plays an important role in detecting these complications in a timely manner and facilitates prompt interventions. Hence, it is important to have knowledge of the expected anatomical alterations following lung cancer surgeries, and the spectrum of post-surgical complications and their respective imaging findings to avoid misinterpretations or delay in diagnosis.

Postoperative cavitating infarction following lobectomy: the importance of variant pulmonary anatomy

A 75-year-old woman was admitted to hospital with haemoptysis, fever and shortness of breath. She had undergone a right video-assisted thoracoscopic surgery upper lobectomy for an apical lung cancer 4 weeks earlier, and had been treated with antibiotics for 1 week prior to admission for a suspected postoperative lung abscess. Review of preoperative imaging found that she possessed a lobar pulmonary artery variant, with postoperative imaging confirming that the right lower lobe segmental pulmonary artery had been divided alongside the upper lobe vessels. The diagnosis of a lung abscess was thus revised to a cavitating pulmonary infarct. There are numerous variations of the pulmonary vasculature, all of which have the potential to cause a range of serious vascular complications if not appreciated preoperatively. Measures to mitigate the risk of complications resulting from vascular anomalies should be considered by both radiologists and surgeons, with effective lines of communication essential to safe working.

The length of the left superior pulmonary vein stump after left upper lobectomy depends on its position to the left atrial appendage

Background

A longer left superior pulmonary vein (LSPV) stump may increase the risk for postoperative cerebral infarction. Although the residual stump is generally longer after left upper lobectomy (LUL) than for other lobectomies, the length of the LSPV stump after LUL may be influenced by the anatomical relationship between the left atrial appendage (LAA) and the LSPV. Our aim in this study was to investigate the influence of this anatomical relationship on the residual length of the LSPV stump after LUL.

Methods

This was a retrospective analysis of 85 patients who underwent LUL at our institution, between January 2014 and March 2018. Based on pre-operative computed tomography (CT) images, the anatomical relationship between the LSPV and the LAA was classified into two patterns, namely an antero-superior and a postero-inferior pattern. The length of the LSPV stump for these two patterns was evaluated on postoperative CT images and compared between the two groups.

Results

Of the 85 patients, 49 were classified in the antero-superior pattern and 36 in the postero-inferior pattern. The mean length of the LSPV stump after LUL, overall, was 21.9 (range, 15–38) mm, with the stump being significantly longer for the antero-posterior (24.2 mm) than postero-inferior (18.9 mm) pattern.

Conclusions

The anatomical relationship between the LSPV and LAA, identified on pre-operative CT images, was associated with the length of the LSPV stump after LUL.

Postoperative complications of pulmonary resection

Thoracic surgery has seen a resurgence in recent years with increasing numbers of cases taken on since the mid-2000s. There has been a paradigm shift in how we manage lung cancer with more emphasis on surgical resection, and this has been aided by minimally invasive video-assisted thoracic surgery (VATS) techniques. As a result, the prevalence of postoperative findings and complications is also increasing, and it is increasingly important for the general radiologist to recognise and diagnose these conditions as thoracic surgical patients may present acutely to non-thoracic surgical institutions. This review will cover both the early and late complications following a variety of lung resection surgeries.

Post-operative imaging of pulmonary vessels

Complications following cardiothoracic surgery are responsible for prolonged hospital stay, increase cost in patient care and increased morbidity and mortality. Vascular complications in particular are significant contributors to poor patient outcome due to either hemorrhage or thrombosis and ischemia. Evaluation of vascular complications in the postoperative patient requires a rapid and reliable imaging approach. Vascular complications after cardiothoracic surgery include pulmonary artery thrombosis, pseudoaneurysm, pulmonary vein thrombosis, vascular fistulas, stenosis and infarction. Multidetector CT (MDCT), often the imaging modality of choice, offers a one-stop-shop capability to visualize the entire cardiothoracic vasculature, airways, lung parenchyma, mediastinum and chest wall with excellent temporal and spatial resolution.

Managing Incidental Findings on Thoracic CT: Mediastinal and Cardiovascular Findings. A White Paper of the ACR Incidental Findings Committee

The ACR Incidental Findings Committee presents recommendations for managing incidentally detected mediastinal and cardiovascular findings found on CT. The Chest Subcommittee was composed of thoracic radiologists who developed the provided guidance. These recommendations represent a combination of current published evidence and expert opinion and were finalized by informal iterative consensus. The recommendations address the most commonly encountered mediastinal and cardiovascular incidental findings and are not intended to be a comprehensive review of all incidental findings associated with these compartments. Our goal is to improve the quality of care by providing guidance on how to manage incidentally detected thoracic findings.

Computed Tomography Angiographic Assessment of Acute Chest Pain

Acute chest pain is a leading cause of Emergency Department visits. Computed tomography angiography plays a vital diagnostic role in such cases, but there are several common challenges associated with the imaging of acute chest pain, which, if unrecognized, can lead to an inconclusive or incorrect diagnosis. These imaging challenges fall broadly into 3 categories: (1) image acquisition, (2) image interpretation (including physiological and pathologic mimics), and (3) result communication. The aims of this review are to describe and illustrate the most common challenges in the imaging of acute chest pain and to provide solutions that will facilitate accurate diagnosis of the causes of acute chest pain in the emergency setting.

Incidence and clinical features of the incidentally found vascular stump thrombus during routine follow up after oncologic lung surgery

OBJECTIVES

We aimed to evaluate the incidence and clinical features of vascular stump thrombus after oncologic lung surgery.

METHODS

A retrospective analysis of records from our institutional database dated between 2009 and 2016 was performed. Data regarding demographics, clinical presentation, medication use, operative findings, pathology, and radiologic findings were retrieved.

RESULTS

The study cohort consisted of 648 oncologic surgeries for primary lung cancer. The incidence of thrombus in the entire population was 5.7% (37/648). Most thrombi were incidentally found on follow-up chest computed tomography scans. Univariate Cox proportional hazard analysis showed that age (p = 0.02), adjuvant therapy (p <0.001), neoadjuvant therapy (p = 0.04), left-sided surgery (p = 0.02), complex surgery greater than simple lobectomy or segmentectomy (p <0.001), advanced stages (p <0.001), non-adenocarcinoma (p = 0.003), and thoracotomy approach (p = 0.009) were associated with an increased risk of vascular stump thrombus. There were no embolic events in our cohort, except for a case of pulmonary thromboembolism. During follow-up, 43.2% (16/37) of thrombi had completely resolved, 48.6% (18/37) showed partial regression and stabilization, and 8.1% (3/37) had progressed.

CONCLUSIONS

The incidence of vascular stump thrombus in our study was not negligible. The clinical course of stump thrombus appears to be benign in most cases. Anticoagulation may be used with caution based on an individual basis depending on each patient's risk factors.

Cardiovascular Computed Tomography Findings after Pneumonectomy: Comparison to Lobectomy

RATIONALE AND OBJECTIVES

To identify and compare cardiovascular findings on computed tomography (CT) scans after pneumonectomy (PNX) with those after lobectomy (LOBX).

MATERIALS AND METHODS

Pre- and postoperative CT scans from 25 PNX patients were retrospectively analyzed and compared to those from 30 LOBX patients. The diameter of the main pulmonary artery (PA) and its ratio to the ascending aorta (PA/Ao) were determined. Cardiac morphometry values were ascertained by measuring maximum diameters of the right and left ventricle on axial (RV_axial, LV_axial) and four-chamber (RV_4-ch, LV_4-ch) views. RV_axial/LV_axial and RV_4-ch/LV_4-ch ratios were calculated. Vessel stumps were evaluated for thrombosis.

RESULTS

After PNX, PA (31.1 ± 5.8 mm vs 28.7 ± 5.4 mm, P = 0.003), PA/Ao (0.97 ± 0.15 vs 0.86 ± 0.12, P = 0.0001), and cardiac morphometry values significantly increased (RV_axial 43.6 ± 7.4 vs 39.4 ± 7.1, P = 0.029; RV_4-ch 41.1 ± 6.3 vs 37.6 ± 5.7, P = 0.041; RV_axial/LV_axial 1.18 ± 0.27 vs 1.03 ± 0.22, P = 0.04; RV_4-ch/LV_4-ch 1.17 ± 0.21 vs 1.02 ± 0.16, P = 0.03). There were no significant differences between right and left PNX. One case of PA stump thrombosis was identified after right PNX. LOBX resulted in a significant increase in PA (30.6 ± 4.3 vs 28.7 ± 3.5, P = 0.005) and PA/Ao (0.90 ± 0.09 vs 0.85 ± 0.10, P = 0.017), whereas cardiac morphometry values were not significantly changed compared to baseline values. No vessel stump thrombosis was observed after LOBX. In comparison to LOBX, all ascertained values were significantly elevated after PNX.

CONCLUSIONS

Morphologic alterations of the cardiovascular system following PNX can be identified on CT scans. Alterations are more distinct after PNX compared to LOBX.

Clinical characteristics of in-situ pulmonary artery thrombosis in Korea

Little is known regarding the clinical features and course of in-situ pulmonary artery thrombosis (PAT). The aim of the present study was to investigate the clinical characteristics of PAT. Patients with PAT were retrospectively identified from a tertiary referral center in South Korea. A control group consisted of patients with pulmonary embolism in whom the right or left pulmonary artery was the largest pulmonary embolism-involved site. We compared various clinical parameters between the two groups. Of the 23 PAT patients, the most common underlying condition was tuberculosis-destroyed lung [11 (47.8%)], followed by pulmonary artery stump after lobectomy or pneumonectomy [7 (30.4%)]. In all patients except one, PAT was located in the right or left pulmonary artery. Computed tomography scans demonstrated that clots were completely or partially resolved less frequently in the PAT group than in the control group [4 (25%) versus 62 (90%); P < 0.001]. In the PAT group, three of the seven patients (43%) who had undergone anticoagulation therapy exhibited improvement, and one of the nine patients (11%) who had not received anticoagulation therapy experienced improvement; however, the difference was not significant. Tuberculosis-destroyed lung was the most common underlying condition in Korean PAT patients, followed by pulmonary artery stump after lung resection. The clots in patients with PAT were mostly located in the right or left pulmonary artery, and clot resolution was less frequent in the PAT group compared to the pulmonary embolism group.

Arterial Stump Thrombosis after Lung Resection Surgery: Clinical Presentation, Treatment and Progress

OBJECTIVE

To determine the prevalence of arterial stump thrombosis (AST) after pulmonary resection surgery for lung cancer and to describe subsequent radiological follow-up and treatment.

MATERIAL AND METHODS

Observational, descriptive study of AST detected by computerized tomography angiography (CT) using intravenous contrast. Clinical and radiological variables were compared and a survival analysis using Kaplan-Meier curves was performed after dividing patients into 3 groups: patients with AST, patients with pulmonary embolism (PE), and patients without AST or PE.

RESULTS

Nine cases of AST were detected after a total of 473 surgeries (1.9%), 6 of them in right-sided surgeries (67% of AST cases). Median time to detection after surgery was 11.3 months (interquartile range 2.7-42.2 months), and range 67.5 months (1.4-69.0 months). Statistically significant differences were found only in the number of CTs performed in AST patients compared to those without AST or PE, and in tumor recurrence in PE patients compared to the other 2 groups. No differences were found in baseline or oncological characteristics, nor in the survival analysis.

CONCLUSIONS

In this series, AST prevalence was low and tended to occur in right-sided surgeries. Detection over time was variable, and unrelated to risk factors previous to surgery, histopathology, and tumor stage or recurrence. AST had no impact on patient survival.

Blood stasis may cause thrombosis in the left superior pulmonary vein stump after left upper lobectomy

Background

We previously reported that arterial infarction of vital organs after lobectomy might occur only after left upper lobectomy and be caused by thrombosis in the left superior pulmonary vein stump. We hypothesized that changes in blood flow, such as blood stasis and disturbed stagnant flow, in the left superior pulmonary vein stump cause thrombosis, and this was evaluated by intraoperative ultrasonography.

Methods

From July 2013 to April 2014, 24 patients underwent lobectomy in the Steel Memorial Muroran Hospital. During the procedure, an ultrasound probe was placed at the pulmonary vein stump and the velocity in the stump was recorded with pulse Doppler mode. The peak velocity and the presence of spontaneous echo contrast in the stump were evaluated. After the operation, the patients underwent contrast-enhanced CT within 3 months.

Results

The operative procedures were seven left upper lobectomies, four left lower lobectomies, seven right upper lobectomies, and six right lower lobectomies. Blood flow was significantly slower in the left superior pulmonary vein stump than in the right pulmonary vein stumps. However, that was not significantly slower than that in the left inferior pulmonary vein stump. Spontaneous echo contrast in the pulmonary vein stump was seen in three patients who underwent left upper lobectomy. Of the three patients with spontaneous echo contrast, two patients developed thrombosis in the left superior vein stump within 3 months after the operation. There was no patient who developed arterial infarction.

Conclusions

In patients who underwent left upper lobectomy, intraoperative ultrasonography to evaluate blood flow and the presence of spontaneous echo contrast in the left superior pulmonary vein stump may be useful to predict thrombosis that may cause arterial infarction.

Electronic supplementary material

The online version of this article (doi:10.1186/s13019-014-0159-8) contains supplementary material, which is available to authorized users.

Left upper lobectomy can be a risk factor for thrombosis in the pulmonary vein stump

Background

Thrombosis in the left upper pulmonary vein stump after left upper lobectomy is a very rare but important complication because it occurs in the systemic circulation system. We previously made the first ever report on the frequency and risk factors of thrombosis in the pulmonary vein stump after lobectomy. In this study, we conducted an investigation in a different hospital to determine whether this was a common complication.

Methods

From 2008 to 2012, 151 patients who underwent lobectomy and following enhanced CT within 2 years after the operation were studied. Postoperative contrast-enhanced CT imaging was retrospectively checked.

Results

We found thrombosis in the pulmonary vein stump in 5 of the 151 patients (3.3%). All 5 patients underwent left upper lobectomy (17.9% of the patients who underwent left upper lobectomy). These 5 patients did not have infarction of any vital organ. The thrombus was disappeared several months later on contrast-enhanced CT in 3 patients and followed in 2 patients. On univariate analysis, there was a significant difference only in the operative procedure (p < 0.001).

Conclusions

Thrombosis in the pulmonary vein stump occurred with high frequency in patients who underwent left upper lobectomy. Because the frequency of thrombosis in this study was the same as in our previous report, this might be a common complication.

Acute pulmonary embolism after pneumonectomy

Pulmonary embolism (PE) by occlusion of the pulmonary arterial bed may lead to acute life-threatening but potentially reversible right ventricular failure, one of the most severe complications of thoracic surgery. Still, the incidence of acute pulmonary embolism after surgery is reduced by comprehensive anticoagulant prevention, improved surgical techniques, appropriate perioperative management and early ambulation. However, there is difficulty in diagnosing PE after thoracic surgery due to the lack of specific clinical manifestations. So that optimal diagnostic strategy and management according to the clinical presentation and estimated risk of an adverse outcome is fundamental.

Delayed formation of pulmonary artery stump thrombus: a case report and review of the literature

Pulmonary artery stump thrombosis is a recognized complication after pneumonectomy. However, to our knowledge, there is only one case report of delayed development of this complication. We report the case of a 68 year-old man who presented with chest pain nearly ten years after undergoing a right pneumonectomy for lung cancer. Workup identified a pulmonary artery stump thrombosis. Due to the acute onset of his symptoms, the patient was anticoagulated, and his chest pain resolved. While the literature suggests that anticoagulation is not generally required for stump thromboses, we highlight features of this case that may indicate an increased risk of clinically important sequelae. Taking previous reports into account, we argue that a specific subset of patients with stump thrombosis may benefit from systemic anticoagulation.

Thrombose in situ du moignon artériel pulmonaire après pneumonectomie

INTRODUCTION

Pulmonary artery stump thrombosis has been reported after pneumonectomy. The prevalence of risk factors for and outcome associated with this condition remain to be clearly evaluated.

CASE REPORT

We describe three cases of pulmonary artery stump thrombosis occurring after pneumonectomy. No pulmonary embolism was observed despite the absence of anticoagulation therapy. The prevalence of arterial stump thrombosis after pneumonectomy has been estimated as 12%. It is often detected by CT scanning performed systematically as part of the routine follow up of lung cancer. Thrombus was identified as a filling defect with concave or convex margins, located at the bottom of the stump.

DISCUSSION

Only one case of pulmonary embolism associated with pulmonary artery stump thrombosis has been described. The absence of complications associated with thrombus in this site suggests that anticoagulant therapy is not likely to be of benefit.