Pulmonary Artery Pseudoaneurysm: A Rare Cause of Fatal Massive Hemoptysis

Abstract

Pulmonary artery pseudoaneurysm (PAPA), an uncommon complication of pyogenic bacterial and fungal infections and related septic emboli, is associated with high mortality. The pulmonary artery (PA) lacks an adventitial wall; therefore, repeated endovascular seeding of the PA with septic emboli creates saccular dilations that are more likely to rupture than systemic arterial aneurysms. The most common clinical presentation of PAPA is massive hemoptysis and resultant worsening hypoxemia. Computed tomography angiography is the preferred diagnostic modality for PAPA; typical imaging patterns include focal outpouchings of contrast adjacent to a branch of the PA following the same contrast density as the PA in all phases of the study. In mycotic PAPAs, multiple synchronous lesions are often seen in segmental and subsegmental PAs due to ongoing embolic phenomena. The recommended approach for a mycotic PAPA is prolonged antimicrobial therapy; for massive hemoptysis, endovascular treatment (e.g., coil embolization, stenting, or embolization of the feeding vessel) is preferred. PAPA resection and lobectomy are a last resort, generally reserved for patients with uncontrolled hemoptysis or pleural hemorrhage. We present a case of a 28-year-old woman with necrotizing pneumonia from intravenous drug use who ultimately died from massive hemoptysis and shock after a ruptured PAPA.

A complicated presentation of pediatric COVID‐19 with necrotizing pneumonia and pulmonary artery pseudoaneurysms

“…Treatment options include transcatheter embolization with coils or endovascular stents, surgical ligation, or even wedge resections and lobectomy. 5 In our case, after multidisciplinary discussion, intravascular occlusion was not pursued in the acute phase. There was no identifiable single PAPA of greatest risk of bleeding, and the extensive multilobar involvement precluded occluding all the PAPAs as this would have left him with insufficient perfusing lung tissue.…”

“…5 PAPAs are rarely defined as a complication of NP. 5 Pathophysiologically, PAPAs form due to the pulmonary artery lacks an adventitial wall; therefore, repeated endovascular seeding of the pulmonary artery with septic emboli creates saccular dilations that are more likely to rupture than systemic arterial aneurysms. 5 It is unclear how the COVID-19-associated prothrombotic state affectes development of PAPAs.…”

Self-resolving pulmonary artery pseudoaneurysm

“…There are a number of case reports on PAPAs occurring secondary to necrotising pneumonia1–4 but none of these cases opted for observation; the patient either died due to massive haemoptysis3 or the PAPA was treated 1 2 4. When comparing our case, the only two potential factors which differed were severe unremitting haemoptysis3 4 or multi-drug resistant pneumonia,1 neither of which our patient had. Therefore, it may be that these are two potential factors that could play a role in the spontaneous resolution of a PAPA.…”

A Conservative Approach to a Large Mycotic Pulmonary Pseudoaneurysm

“…There are only several reported cases of mycotic pulmonary artery aneurysms [ 2 ]. Although these cases are rare, they carry high associated mortalities of up to 50% [ 1 ]. The high mortality may be related to the architecture of the pulmonary arteries, as they lack an adventitial wall layer and are more likely to rupture than systemic aneurysms [ 1 ].…”

“…Timely diagnosis with appropriate imaging is crucial and requires a high index of suspicion. Early detection is important to instate prompt antimicrobial therapy and plan for potential management, as the mortality rate associated with pulmonary pseudoaneurysm rupture is greater than 50% [ 1 ].…”