Underuse of reperfusion therapy with systemic thrombolysis in high-risk acute pulmonary embolism in a Portuguese center.

INTRODUCTION: Reperfusion therapy is generally recommended in acute high-risk pulmonary embolism (HR-PE), but several population-based studies report that it is underused. Data on epidemiology, management and outcomes of HR-PE in Portugal are scarce. OBJECTIVE: To determine the reperfusion rate in HR-PE patients, the reasons for non-reperfusion, and how it influences outcomes. METHODS: In this retrospective cohort study of consecutive HR-PE patients admitted to a thromboembolic disease referral center between 2008 and 2018, independent predictors for non-reperfusion were assessed by multivariate logistic regression. PE-related mortality and long-term MACE (cardiovascular mortality, PE recurrence and chronic thromboembolic disease) were calculated according to the Kaplan-Meier method. Differences stratified by reperfusion were assessed using the log-rank test. RESULTS: Of 1955 acute PE patients, 3.8% presented with hemodynamic instability. The overall reperfusion rate was 50%: 35 patients underwent systemic thrombolysis, one received first-line percutaneous embolectomy and one rescue endovascular treatment. Independent predictors of non-reperfusion were: age, with >75 years representing 12 times the risk of non-treatment (OR 11.9, 95% CI 2.7-52.3, p=0.001); absolute contraindication for thrombolysis (31.1%), with recent major surgery and central nervous system disease as the most common reasons (OR 16.7, 95% CI 3.2-87.0, p<0.001); and being hospitalized (OR 7.7, 95% CI 1.4-42.9, p=0.020). At a mean follow-up of 2.5±3.3 years, the survival rate was 33.8%. Although not reaching statistical significance for hospital mortality, mortality in the reperfusion group was significantly lower at 30 days, 12 months and during follow-up (relative risk reduction of death of 64% at 12 months, p=0.013). Similar results were found for MACE. CONCLUSIONS: In this population, the recommended reperfusion therapy was performed in only 50% of patients, with advanced age and absolute contraindications to fibrinolysis being the main predictors of non-reperfusion. In this study, thrombolysis underuse was associated with a significant increase in short- and long-term mortality and events.

Continuous Aspiration Mechanical Thrombectomy for the management of intermediate- and high-risk pulmonary embolism: Data from the first cohort in Portugal.

INTRODUCTION: This study describes the experience of a reference center using continuous aspiration mechanical thrombectomy for acute high- and intermediate-high-risk pulmonary embolism (PE). METHODS: Twenty-nine consecutive patients with acute central PE (48.3% high-risk PE; 82.8% in class >III from the original Pulmonary Embolism Severity Index score; median Charlson Comorbidity Index of 4) were treated with the Indigo® Mechanical Thrombectomy System between March 2018 and March 2020. Technical success was defined as successful placement of the device and initiation of aspiration thrombectomy. Clinical success was defined as any improvement in hemodynamic and/or oxygenation parameters, pulmonary hypertension or right heart strain at 48 hours, and survival to hospital discharge. Safety was defined as freedom from severe adverse events potentially related to the procedure. Three-month follow-up results were collected. RESULTS: Technical success was 96.6%. Miller index and systolic pulmonary arterial pressure were significantly reduced after the procedure (-5.5±3.0, and -10.2±11.5 mmHg, respectively, both p<0.001). There was a significant improvement in mean paO2/FiO2 ratio (+77.1±103.2; p=0.001), shock index (-0.4±0.4; p<0.001), need for aminergic support at 48 h after the procedure (-75.0%, p=0.006) and improvement in right ventricular function in 66.6% (p=0.008). Clinical success was 75.9%. Severe adverse event rate was 10.3%: two deaths during the procedure and one pulmonary macroembolization during device progression. In-hospital and three-month survival rates were 82.8% and 72.4%, respectively. CONCLUSIONS: Aspiration thrombectomy for acute high- and intermediate-high-risk PE is feasible with a high technical and clinical success rate. Nevertheless, all-cause mortality is still high, probably related to the baseline high-risk features of the studied population and associated comorbidities.