Anthracofibrosis mimicking chronic thromboembolic pulmonary hypertension

We present the case of a 78‐year‐old female undergoing pulmonary endarterectomy (PEA) because of suspected chronic thromboembolic pulmonary hypertension (CTEPH). During surgery firm black masses were encountered in the aortopulmonary window and on the cranial part of the right pulmonary artery (PA). After PA arteriotomy we visualized intraluminal black firm stenosing plaques at the orifices of the three right and of the left lingular and lower lobar branches. Since no dissection plane could be obtained the procedure was discontinued. Subsequent bronchoscopy visualized a submucosal dark black‐blue discoloration in both main bronchi. Pathological analysis revealed anthracofibrosis, which could be explained by biomass smoke exposure in the past. We are the first to provide intravascular pictures and pathologic images of this very rare entity. Moreover, we report stenoses at the orifices of the three right‐sided lobar and of the left‐sided lingular and lower lobe arteries, in contrast to three previous reports that report on single locations caused by extrinsic PA compression from lymphadenopathy. Our case, however, suggests extension of fibrosis with anthracotic pigment into the PA wall. We conclude that in the absence of a clear history of exposure to carbon smoke and with consequently no diagnostic bronchoscopy, anthracofibrosis of the lungs may mimic CTEPH not only by external compression but also by extension into pulmonary vascular structures. PEA‐surgery should not be attempted in these cases.