Intraluminal Arterial Filling Defects Misdiagnosed as Pulmonary Emboli: What Else Could They Be?

Chronic inflammatory pulmonary artery lesion causing right pulmonary artery stenosis 15 years post Blalock-Taussig shunt ligation

Discrete central endovascular pulmonary arterial lesions raise clinical concern for malignancy such as primary pulmonary artery sarcoma. We present a case of a female in her late teens who had an obstructive mid right pulmonary artery lesion found on follow-up imaging 15 years after Tetralogy of Fallot repair. The lesion was in the vicinity of a previously ligated Blalock-Taussig shunt and causing right PA stenosis with delayed perfusion to the right lung, and a flow-related distal left PA aneurysm. The lesion was excised and confirmed histologically to be inflammatory in nature. Intraoperative microbiology demonstrated growth of the Kytococcus species, and she was managed with 6 weeks of intravenous antibiotics, with a full recovery.

Radiologic mimics of pulmonary embolism

The diagnosis of pulmonary embolism (PE) is often made more challenging by the presence of diseases that can mimic thromboembolic disease. There is no specific or sensitive constellation of clinical signs or symptoms that can be used to diagnose PE. Ventilation/perfusion scans can have false-positive findings related to mediastinal conditions that can compress the pulmonary arteries, and pulmonary hemorrhage can resemble PE on V/Q scanning with potentially devastating consequences if anticoagulation is started. CT-scan related issues l eading to potential false-positive diagnoses range from inadequate imaging technique, to systemic-pulmonary shunting, to non-thrombotic occlusion of pulmonary arteries by tumor, septic emboli, and emboli of fat, air, and foreign material, as well as vasculitic processes. Careful assessment of the patient and consideration of these potential mimickers is imperative to correct diagnosis of this potentially life-threatening condition.

Undifferentiated intimal sarcoma of the pulmonary artery: A case report

BACKGROUND

Since 1923, only a few hundred cases of pulmonary arterial sarcoma (PAS) have been reported. It is easy for PAS to be misdiagnosed as pulmonary thromboembolism, which makes treatment difficult. The median survival time without surgical treatment for PAS is only 1.5-3 mo. Echocardiography is widely used in screening for pulmonary artery space-occupying lesions in patients with chest pain, dyspnea, and cough; furthermore, it is typically considered the first imaging examination for patients with PAS.

CASE SUMMARY

In May 2017, a 39-year-old male patient experienced chest pain with no particular obvious cause. At that time, the cause was thought to be pulmonary embolism. In July 2017, positron emission tomography–computed tomography revealed space-occupying lesions in the right lung and multiple metastases in both lungs. The lesions of the right lung were biopsied, and pathology revealed undifferentiated sarcoma. Chemotherapy had been performed since July 2017 in another hospital. In December 2019, the patient was admitted to our hospital for the sake of CyberKnife treatment. Echocardiography suggested: (1) A right ventricular outflow tract (RVOT) solid mass of the main pulmonary artery; and (2) mild pulmonary valve regurgitation. Ultrasonography showed the absence of a thrombus in the deep veins of either lower limb.

CONCLUSION

PAS is a single, central space-occupying lesion involving the RVOT and pulmonary valve. Echocardiography of PAS has its own characteristics.

The filling defect of pulmonary artery, an imaging finding what we should know

The most common cause of pulmonary artery filling defects on computed tomography pulmonary angiography or magnetic resonance imaging is pulmonary thromboembolism, but not infrequently, the presentation of this finding lacks specificity. Given that the morbidity and mortality associated with pulmonary thromboembolism is high, proper diagnosis of the condition is essential. Unusual or more rarely encountered etiologies must be considered when clinical manifestations and imaging findings are inconsistent. With this review, our purpose is to describe possible causes of pulmonary arterial filling defects. We aim to provide clinicians with a comprehensive list of differential diagnoses to facilitate a measured approach to the assessment of pulmonary arterial filling defects on computed tomography pulmonary angiography or magnetic resonance imaging.

Non-thrombotic pulmonary embolism in emergency CT

Non-thrombotic pulmonary embolism (NTPE) results from the embolization of non-thrombotic materials. It can often be a challenging diagnosis due to non-specific (similar to thrombotic pulmonary embolism) or uncommon clinical and imaging findings. Patients with NTPE often present to the emergency department with acute respiratory distress, and contrast-enhanced computed tomography (CT) of the chest and CT pulmonary angiography are the imaging modalities of choice for respiratory distress. Since the treatment of NTPE is entirely different from thromboembolism, its distinction is essential. Moreover, early diagnosis of NTPE is necessary. Radiologists must be familiar with the diagnostic findings of NTPE, and this article aims to review the imaging features of various causes of NTPE.

Balloon angioplasty or stent implantation for pulmonary vein stenosis caused by fibrosing mediastinitis: a systematic review

Fibrosing mediastinitis (FM) is a very rare disease, often caused by histoplasmosis capsulatum, tuberculosis, sarcoidosis, autoimmunity and other diseases, such as IgG 4-related diseases. Fibrous structures in the mediastinum compress the pulmonary artery, pulmonary vein, superior vena cava, esophagus, trachea and cardiac vessels, leading to clinical symptoms. Drug therapeutic modality for pulmonary vein stenosis (PVS) caused by FM is palliative in essence and with limited efficacy, whereas surgical treatment causes high mortality. In recent years, catheter-based treatment to FM-caused PVS has emerged as a promising therapeutic modality, however, the safety and effectiveness of this modality remain unclear. Therefore, a systematic review on the safety and efficacy of the catheter-based treatment for PVS caused by FM was performed, in the hope to shed lights on the alternative therapeutic strategy to this fatal disease.