Incidental Discovery of a Chronically Dissected Pulmonary Artery

Abstract

Pulmonary artery dissection is a rare and potentially fatal vascular emergency most often associated with pulmonary hypertension. In this report, we describe the incidental discovery of a chronically dissected pulmonary artery in a 92-year-old woman who presented to the emergency department with abdominal discomfort, constipation, and poor appetite. Imaging to evaluate for occult malignancy revealed a dissection flap within the main pulmonary artery and findings suggestive of chronicity. These radiographic findings included parenchymal scarring of the left lung, calcification, and collateralization of pulmonary vessels. Given the patient's age and lack of symptoms, no invasive treatment approach was pursued after multidisciplinary discussion. Classically considered a deadly disease, pulmonary artery dissection may not be as universally fatal as once thought and may present subclinically, remaining undetected for extended periods of time. Early recognition of atypical and indolent presentations is essential, especially in an era of widespread cross-sectional imaging and in patients for whom invasive intervention may not be appropriate.

Keywords: chronic dissection; chronic pulmonary hypertension; internal med; pulmonary artery dissection; pulmonary critical care; pulmonary trunk.

Figure 1. Pulmonary Artery Dissection on Contrast-Enhanced Chest CT

A dissection flap within the main pulmonary artery (A) appears to extend into the lobar artery of the left lower lobe, resulting in thrombus and occlusion. Parenchymal disease in the left lower lobe (B) and a relatively dilated right main pulmonary artery can suggest either increased compensatory flow to a non-diseased right lung or underlying pulmonary artery hypertension. Chronicity of this finding was further supported by contrast-filled collateral vessels supplying the inferior portion of the left lower lobe (C,D).

Figure 2. Pre-admission Chest Radiograph

Pre-admission chest radiograph notable for nonspecific airspace disease within the left lower lung, retrocardiac area. Although more evident in retrospect, the right pulmonary, interlobar, and right lower lobar arteries appear dilated. This was concordant with findings on CT.