Idiopathic pulmonary artery dissection: a case report

Arterial dissections: Common features and new perspectives

Arterial dissections, which involve an abrupt tear in the wall of a major artery resulting in the intramural accumulation of blood, are a family of catastrophic disorders causing major, potentially fatal sequelae. Involving diverse vascular beds, including the aorta or coronary, cervical, pulmonary, and visceral arteries, each type of dissection is devastating in its own way. Traditionally they have been studied in isolation, rather than collectively, owing largely to the distinct clinical consequences of dissections in different anatomical locations - such as stroke, myocardial infarction, and renal failure. Here, we review the shared and unique features of these arteriopathies to provide a better understanding of this family of disorders. Arterial dissections occur commonly in the young to middle-aged, and often in conjunction with hypertension and/or migraine; the latter suggesting they are part of a generalized vasculopathy. Genetic studies as well as cellular and molecular investigations of arterial dissections reveal striking similarities between dissection types, particularly their pathophysiology, which includes the presence or absence of an intimal tear and vasa vasorum dysfunction as a cause of intramural hemorrhage. Pathway perturbations common to all types of dissections include disruption of TGF-β signaling, the extracellular matrix, the cytoskeleton or metabolism, as evidenced by the finding of mutations in critical genes regulating these processes, including LRP1, collagen genes, fibrillin and TGF-β receptors, or their coupled pathways. Perturbances in these connected signaling pathways contribute to phenotype switching in endothelial and vascular smooth muscle cells of the affected artery, in which their physiological quiescent state is lost and replaced by a proliferative activated phenotype. Of interest, dissections in various anatomical locations are associated with distinct sex and age predilections, suggesting involvement of gene and environment interactions in disease pathogenesis. Importantly, these cellular mechanisms are potentially therapeutically targetable. Consideration of arterial dissections as a collective pathology allows insight from the better characterized dissection types, such as that involving the thoracic aorta, to be leveraged to inform the less common forms of dissections, including the potential to apply known therapeutic interventions already clinically available for the former.

Spontaneous idiopathic pulmonary artery dissection with ST segment elevation in Leads aVR and V1

Pulmonary artery dissection is a rare condition that often occurs on the basis of pulmonary arterial hypertension and causes complications such as cardiogenic shock and sudden death. Additionally, this condition can be idiopathic. A 59-year-old male patient with no previous history of disease presented to our clinic with chest pain and shortness of breath. Coronary arteries were normal on coronary angiography in the patient who had a positive troponin test result and ST segment elevation in leads V1, V2, V3 and aVR. Pulmonary embolism was suspected in the patient whose condition worsened. Pulmonary artery dissection was diagnosed via the contrast-enhanced computed tomography and sudden cardiac death occurred. In conclusion, pulmonary artery dissection may cause aVR segment elevation on electrocardiography.

Fallot Tetralogy with Dissected Pulmonary Artery Aneurysm: A Rare Case Report

Pulmonary artery dissection is a rare and extremely dangerous disease with high mortality rates. It is one of the most serious complications of chronic pulmonary hypertension. It may be related to chronic pulmonary hypertension and pulmonary artery dilatation. Early diagnosis of pulmonary dissection is particularly important because of its high mortality. Once the symptoms worsen or severe deterioration of the disease occurs, imaging examination should be performed promptly for early diagnosis and timely treatment.

Rare Presentation of Left Lower Lobe Pulmonary Artery Dissection

Background. Pulmonary arterial dissection with chronic pulmonary arterial hypertension as its major cause is a very rare but life-threatening condition. In most cases the main pulmonary trunk is the affected site usually without involvement of its branches. Segmental or lobar pulmonary artery dissection is extremely rare. Case Presentation. We report a unique case of left lower lobe pulmonary artery dissection in a 70-year-old male, with confirmed chronic pulmonary hypertension. To confirm dissection MDCT pulmonary angiography was used. Multiplanar reformation (MPR) images in sagittal, coronal, oblique sagittal, and curved projections were generated. This case report presents morphologic CT features of rare chronic left lobar pulmonary artery dissection associated with chronic pulmonary hypertension at a place of localised pulmonary artery calcification. CT pulmonary angiography excluded signs of thromboembolism and potential motion or flow artefacts. Conclusion. To the best of our knowledge, no case of lower lobe pulmonary artery dissection with flap calcification has been reported yet. CT imaging of the chest is a key diagnostic tool that is able to detect an intimal flap and a false lumen within the pulmonary arterial tree and is preferred in differential diagnosis of rare complications of sustained pulmonary arterial hypertension.

Dual-energy CT-based iodine quantification for differentiating pulmonary artery sarcoma from pulmonary thromboembolism: a pilot study

OBJECTIVES

The purpose of this study was to determine whether dual-energy computed tomography (DECT) angiography could differentiate pulmonary thromboembolism (PTE) from pulmonary artery sarcoma (PAS).

METHODS

We prospectively enrolled 19 patients that had a filling defect in the main pulmonary artery on DECT. Six patients who had PAS and underwent DECT were retrospectively enrolled for comparison. Pathological results or follow-up CT after anticoagulation therapy were used to make the final diagnosis. Two investigators measured the following parameters at the filling defect in the main pulmonary artery: CT attenuation density [Hounsfield units (HU)], iodine-related HU (IHU) and iodine concentration (IC, mg/ml).

RESULTS

From a total of 25 patients (M:F = 10:15; mean age, 65 years old), 19 were categorised into the PTE group and six were categorised into the PAS group. The mean HU values were not significantly different between the PTE and PAS groups (45.5 ± 15.9 vs 47.1 ± 9.2 HU; P = 0.776). However, the mean IHU and IC values of the lesions were significantly different between the PTE and PAS groups (10.6 ± 7.2 vs 27.9 ± 9.1 HU; P = 0.004, and 0.61 ± 0.39 vs 1.49 ± 0.57; P = 0.001).

CONCLUSIONS

DECT angiography using a quantitative analytic methodology can be used to differentiate PTE and PAS.

KEY POINTS

• DECT can be useful for differentiation of PAS and PTE. • With quantitative analysis, DECT offers tissue characterisation by detecting lesion parameter increases. • The patients without predisposing factors for PTE can be candidates for DECT.

Spontaneously developed pulmonary arterial intramural hematoma that mimicked thromboembolism

A 65-year-old woman visited our hospital with a complaint of acute onset dyspnea and radiological manifestations of pulmonary thromboembolism. The patient underwent an exploratory surgery to find a whitish-blue colored mass occupying almost the whole lumen of the main pulmonary arteries. Based on the pathological and radiological findings, the patient was diagnosed to have a pulmonary arterial intramural hematoma. Intramural hematomas are usually observed in the walls of the aorta, and we believe that an isolated intramural hematoma in the pulmonary artery has not been described previously.

Ruptured pulmonary artery aneurysm: a surgical emergency

Idiopathic pulmonary artery aneurysm rupture was diagnosed in a 79-year-old man who presented with a dry cough. He was considered unlikely to tolerate extensive pulmonary artery reconstruction or lung resection; hence, he was salvaged by timely ligation of the distal pulmonary artery at the origin of the aneurysm.