Acute intermediate-risk pulmonary embolism (PE), defined by evidence of right ventricular (RV) dysfunction in a normotensive patient, represents more than half of all diagnosed PEs. The natural history of intermediate-risk PE includes resolution of RV dysfunction, chronic RV dysfunction, development of chronic thromboembolic pulmonary hypertension (CTEPH), and death. RV dysfunction has been directly correlated with short-term mortality. In addition, studies have demonstrated that chronic RV dysfunction and CTEPH may correlate with the size of the perfusion defect. The mainstay of treatment in intermediate-risk PE remains anticoagulation. However, thrombolysis has previously been shown to more rapidly reduce RV dysfunction in the acute period. Recent advances in catheter-directed intervention (CDI), such as thrombus aspiration, fragmentation, and directed thrombolysis, have enabled their use in intermediate-risk PE with demonstrable safety. Understanding which patients would benefit from anticoagulation alone and which should be offered CDI could lead to a reduction in chronic RV failure and CTEPH. We retrospectively reviewed patients who presented to our institution during a 2-year period with a diagnosis of acute intermediate-risk PE. A comparison was made between those receiving medical therapy alone with therapeutic anticoagulation and those treated by CDI with either thrombolysis using the EKOS catheter (EKOS Corporation, Bothell, Wash) or percutaneous thrombectomy/aspiration using the FlowTriever device (Inari Medical, Irvine, Calif). Data collected included demographics, comorbidities, hospital and intensive care unit length of stay, major complications, 30-day mortality, resolution of RV failure, and development of CTEPH. Fifty patients were analyzed; 24 underwent CDI and 26 underwent medical management. Those who were chosen to undergo CDI had higher rates of severe RV failure (71% vs 42%; P = .05) and higher rates of central PE (96% vs 52%; P = .0008) on presentation. The 30-day mortality of the intervention group and the medical group was similar at 4.2% and 3.9%, respectively. Hospital stay and intensive care unit length of stay were also similar. Those who underwent CDI had lower rates of chronic RV failure (23% vs 50%; P = .27; Fig 1) and CTEPH (4% vs 15%; P = .35). Patients with a central PE who had CDI had a statistically significant lower rate of CTEPH development (4% vs 31%; P = .047; Fig 2). There was no difference in outcomes between those undergoing thrombolysis and those undergoing thrombectomy/aspiration. Adequately selected patients presenting with an intermediate-risk PE may benefit from CDI to prevent the development of chronic RV failure and CTEPH, especially those who have a centrally located PE on presentation.Fig 2Development of chronic thromboembolic pulmonary hypertension (CTEPH) in patients with central pulmonary embolism (PE).View Large Image Figure ViewerDownload Hi-res image Download (PPT)
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