What's next after the clot? Residual pulmonary vascular obstruction after pulmonary embolism: From imaging finding to clinical consequences.

Surviving an embolism exposes patients to potential long-term complications, such as altered quality of life, persistent dyspnea, impaired exercise capacity or pulmonary hypertension. The common objective factor in most of these situations is the presence of residual pulmonary vascular obstruction (RPVO). Planar ventilation/perfusion scintigraphy (V/Q lung scan) is the gold standard for assessing RPVO, which occurs in 46 to 66% of patients at 3 months and persists in 25 to 29% of patients a year after acute PE. Assessed early (i.e. before discharge), RPVO could predict acute PE development with a high negative predictive value. Evaluated after anticoagulation therapy, RPVO could help to manage anticoagulation treatment and predict the risk of PE recurrence and patients identified at risk of developing chronic thromboembolic pulmonary hypertension. In this comprehensive review, we provide an overview of the current knowledge of RPVO after PE from imaging diagnosis to clinical consequences. In the first part, we mainly focus on the imaging modalities capable of detecting and quantifying RPVO. We then focus on the symptoms and syndromes linked with this residual obstruction after PE. Although the occurrence of RPVO and long-term complications varies greatly from one patient to another, we finally aim to identify the patients and diseases at risk of developing residual obstruction.

Chronic thromboembolic pulmonary hypertension suspicion after pulmonary embolism in cancer patients.

INTRODUCTION: Chronic thromboembolic pulmonary hypertension (CTEPH) is a severe condition which should be screened in patient with persistent dyspnea after pulmonary embolism (PE). After PE, CTEPH incidence was estimated between 0.1 and 9.1% in overall patients. Although cancer is associated with an increased risk of CTEPH, CTEPH incidence is still unknown in cancer patients with PE. We aimed to estimate the frequency CTEPH-likely patients after PE, in cancer patients. MATERIALS: We individualized cancer patients of a monocentric prospective registry including consecutive patients with symptomatic PE. The primary outcome was the frequency of "CTEPH-likely" patients defined by the European Respiratory Society (ERS) guidelines (an accelerated tricuspid regurgitation more than 2.8m/s and at least 1-2 segmental or larger-sized defects, after more than 3 months of therapeutic anticoagulation). RESULTS: We included 129 cancer patients with PE. Colorectal cancer (19%), breast cancer (17%) and prostate cancer (15%) were the most frequent cancers. PE occurred after surgery or medical immobilization in 17% of patients, while 26% of patients had history of venous thromboembolism. During the follow-up, 2 patients (1.5%) had a clinical suspicion of CTEPH and only 1 patient with ovarian cancer (0.75% 95%CI [0.0%-2.2%]) was classified as "CTEPH-likely", 6 months after PE. CONCLUSION: The frequency of screening for CTEPH seems negligible in PE patients with cancer. Concomitant cancer may affect the clinical suspicion of CTEPH.