Congenital Bronchial Artery to Pulmonary Artery Fistula Presenting as Hemoptysis

Bronchial artery to pulmonary artery fistula initially misdiagnosed as pulmonary embolism: A case report

INTRODUCTION

Bronchopulmonary arterial fistulas have been reported following lung transplant, and in association with COPD, trauma, radiation therapy, and infection. They may also arise congenitally. Embolization is the most frequent treatment.

CASE PRESENTATION

We present a case of a 58-year-old male with a prior history of pulmonary tuberculosis who initially presented with minimal hemoptysis for several months. Right upper lobe bronchial artery to pulmonary artery fistulas were discovered by angiography. These were excluded by particle and microcoil embolizations.

CLINICAL DISCUSSION

Relatively unopacified blood from bronchial artery enters right pulmonary artery and causes ill-defined hypodensities mixing with opacified blood, especially compared to uniformly, brightly enhancing left pulmonary artery. As a result, interpreters will frequently incorrectly conclude that right pulmonary artery embolism exists rather than a bronchopulmonary arterial fistula.

CONCLUSION

In most cases, bronchopulmonary arterial fistulas are treated by bronchial artery embolization; however, direct puncture or stent grafting are alternate considerations depending on the patient's anatomy. In all instances, a multidisciplinary approach is a must.

Pre-operative embolization of a complex systemic to pulmonary vascular malformation

A 38-year-old male patient presenting with mild exertional dyspnea was noted to have a lingular opacity on chest radiograph. CT of the chest demonstrated an unusual complex inferior lingular vascular malformation with branches arising from the left internal thoracic artery and the left inferior diaphragmatic artery via the celiac artery. There was suspected communication with both pulmonary arterial and venous branches. Following thorough assessment and comprehensive clinical investigation, the patient elected to proceed to definitive surgical management due to potential risk of life-threatening hemoptysis. Interventional radiology performed pre-operative diagnostic angiography and embolization of the systemic feeding arteries. The patient proceeded to have an uncomplicated video-assisted thoracoscopic surgery segmentectomy and was discharged the next day. The patient was asymptomatic at follow-up with complete resolution of the malformation on CT at 6 months. We discuss an uncommon pathology which benefited from multidisciplinary management including successful pre-operative endovascular embolization.

Development of a model to predict recurrence after bronchial artery embolization for non-cancer related hemoptysis

Background

Relapse after effective bronchial arterial embolization (BAE) for controlling hemoptysis is not uncommon. Studies reported diverse predictors of recurrence. However, a model to assess the probability of recurrence in non-cancer related hemoptysis patients after BAE has not been reported. This study was to develop a model to predict recurrence after BAE for non-cancer related hemoptysis.

Methods

The study cohort included 487 patients who underwent BAE for non-cancer-related hemoptysis between January 2015 and December 2019. We derived the model’s variables from univariate and multivariate Cox regression analyses. The model presented as a nomogram scaled by the proportional regression coefficient of each predictor. Model performance was assessed with respect to discrimination and calibration.

Results

One-month and 1-, 2-, 3- and 5-year recurrence-free rates were 94.5%, 88.0%, 81.4%, 76.2% and 73.8%, respectively. Risk factors for recurrence were underlying lung diseases and the presence of systemic arterial-pulmonary circulation shunts. This risk prediction model with two risk factors provided good discrimination (area under curve, 0.69; 95% confidence interval, 0.62–0.76), and lower prediction error (integrated Brier score, 0.143).

Conclusion

The proposed model based on routinely available clinical and imaging features demonstrates good performance for predicting recurrence of non-cancer-related hemoptysis after BAE. The model may assist clinicians in identifying higher-risk patients to improve the long-term efficacy of BAE.

CT for Evaluation of Hemoptysis

Hemoptysis, which is defined as expectoration of blood from the alveoli or airways of the lower respiratory tract, is an alarming clinical symptom with an extensive differential diagnosis. CT has emerged as an important noninvasive tool in the evaluation of patients with hemoptysis, and the authors present a systematic but flexible approach to CT interpretation. The first step in this approach involves identifying findings of parenchymal and airway hemorrhage. The second step is aimed at determining the mechanism of hemoptysis and whether a specific vascular supply can be implicated. Hemoptysis can have primary vascular and secondary vascular causes. Primary vascular mechanisms include chronic systemic vascular hypertrophy, focally damaged vessels, a dysplastic lung parenchyma with systemic arterial supply, arteriovenous malformations and fistulas, and bleeding at the capillary level. Evaluating vascular mechanisms of hemoptysis at CT also entails determining if a specific vascular source can be implicated. Although the bronchial arteries are responsible for most cases of hemoptysis, nonbronchial systemic arteries and the pulmonary arteries are important potential sources of hemoptysis that must be recognized. Secondary vascular mechanisms of hemoptysis include processes that directly destroy the lung parenchyma and processes that directly invade the airway. Understanding and employing this approach allow the diagnostic radiologist to interpret CT examinations accurately in patients with hemoptysis and provide information that is best suited to directing subsequent treatment. ^©RSNA, 2021.

Bronchopulmonary arteriovenous malformation presenting as cryptogenic hemoptysis in a patient with bicuspid aortic valve

We report the case of a 44-year-old male patient with bicuspid aortic valve, presenting with hemoptysis. Catheter angiography revealed an abnormal communication between bronchial and pulmonary artery, which remained undetected on computed tomography angiography. Angioembolization was done using polyvinyl alcohol and gelfoam particles. This is the first case in literature describing bronchial arteriovenous malformation associated with bicuspid aortic valve.

The multiple systemic artery to pulmonary artery fistulas resulting in severe irreversible pulmonary arterial hypertension in patient with previous history of pneumothorax

Background

Systemic artery to pulmonary artery fistulas (SA-PAFs), are extremely rare in people without congenital heart disease. In this group of patients pulmonary arterial hypertension was reported in the single case. Then, we describe a case of multiple SA-PAFs, which were the cause of severe nonreversible arterial pulmonary hypertension in a patient who had a right-sided pneumothorax 35 years earlier.

Case presentation

52-year-old male Caucasian patient with echocardiographically confirmed pulmonary hypertension (PH) was admitted to cardiology department due to exertional dyspnea and signs of right ventricle failure. Routine screening for causes of secondary PH was negative. Right heart catheterization (RHC) confirmed a high degree arterial PH [mean pulmonary artery pressure (mPAP); 50,6 mmHg, pulmonary wedge pressure (PWP); 11,3 mmHg, pulmonary vascular resistance (PVR); 11,9 Wood’s units (WU)] irreversible in the test with inhaled nitric oxide. Oxygen saturation (SaO₂) of blood samples obtained during the first RHC ranged from 69.3 to 73.2%. Idiopathic pulmonary arterial hypertension was diagnosed. Treatment with inhaled iloprost and sildenafil was initiated.

Control RHC, performed 5 months later showed values of mPAP (59,7 mmHg) and PVR (13,4 WU) higher in comparison to the initial measurement, SaO₂ of blood obtained during RHC from upper lobe artery of the right lung was elevated and amounted 89.7%.

Then, pulmonary arteriography was performed. Lack of contrast in the right upper lobe artery with the evidence of retrograde blood flow visible as a negative contrast in the right pulmonary artery was found. Afterwards, right subclavian artery arteriography detected a huge vascular malformation communicating with right upper lobe artery. Following computed tomography angiogram (angio-CT) additionally revealed the enlargement of bronchial arteries originated fistulas to pulmonary artery of right upper lobe.

In spite of intensive pharmacological treatment, including the therapy of pulmonary hypertension and percutaneous embolisation of the fistulas, the patient’s condition continued to deteriorate further. He died three months after embolisation due to severe heart failure complicated by pneumonia.

Conclusion

Non-congenital SA-PAFs are extremely rare, however, they should be excluded in patients with pulmonary arterial hypertension and history of inflammatory or infectious disease of the lung and pleura, pneumothorax, cancer or Takayashu’s disease and after chest trauma.