High Prevalence of Persistent Breathlessness Following Sub-Massive Pulmonary Embolism in Patients Presenting to a Large Regional Hospital in South Wales.

OBJECTIVE: There is a broad literature exploring the investigation, treatment, management and outcomes of patients suffering from pulmonary embolism (PE). Chronic thromboembolic pulmonary hypertension (CTEPH) has been studied but less is known about outcomes for the large majority of individuals surviving PE who do not have persistent thrombus or CTEPH.
MATERIAL AND METHODS: Radiology, hospital and primary care records were reviewed in patients with central pulmonary emboli presenting to a large hospital in South Wales between 2013-16.
RESULTS: 2501 CTPA were reviewed. 380 (15.2%) showed PE and of these 127 (33.4%) involved the main pulmonary arteries or the pulmonary trunk. 4 patients received systemic and 1 catheter directed thrombolysis. 16 (12.6%) patients died of PE during the admission. Excluding patients dying within 3 months, 49 patients (48.5%) were more SOB than before the pulmonary embolus (73.7 % if there was evidence of right heart strain during admission). Of these 6 patients (12.2%) had evidence of persisting PE and/or pulmonary hypertension. In patients with no evidence of persisting clot or pulmonary hypertension where full lung function was performed there was an isolated reduction in gas transfer measurement (mean TLCO 57%).
CONCLUSION: Many patients remain breathless following large volume PE particularly if there is evidence of Right ventricular strain at presentation. The pathophysiology is unclear but lung function testing is consistent with persisting damage to the pulmonary vascular bed. These findings may allow clinicians to better advise patients of expected outcomes following major pulmonary embolus and may avoid unnecessary further investigation.