Abstract Background: Acute pulmonary embolism (PE) is a significant cause of morbimortality. Epidemiological data in Portugal are limited, potentially leading to underdiagnosis. Catheter-directed therapy (CDT) is a promising alternative treatment, particularly for high-risk patients. Objectives: To evaluate the impact of CDT on intermediate-high-risk and high-risk acute PE. Methods: This is a retrospective single-centre study conducted from 2019 to 2023 in Portugal. Data included patient demographics, clinical presentation, procedural characteristics, and outcomes. Comparisons before and after the procedure were carried out, using two-sided paired Student´s T-test or McNemar´s test. P-value < 0.05 was considered statistically significant. Results: Among the 21 patients included in this study, the mean age was 62.5 (±16.8) years and 57% (n = 12) were female. Bilateral PE was predominant (n=18, 86%), with fifteen patients (75%) classified as high-risk PE and five (25%) as intermediate-high-risk PE. Overweight (n = 12, 57%), hypertension (n = 9, 45%), dyslipidaemia (n = 8, 40%), immobility (n = 4, 20%), and active cancer (n=3, 14%) were prevalent comorbidities. The median Charlson Comorbidity Index score was 3.5 (IQR 1.2–4.0). Two-thirds (n = 10, 67%) of the patients with high-risk PE exhibited contraindications to systemic fibrinolysis, while one-third (n = 5, 33%) had previously undergone failed thrombolysis. CDT improved hemodynamic parameters, significantly reducing the right ventricular (RV) dysfunction after the procedure (72.2% vs 23.5%, p=0.008). There was a low incidence of bleeding complications, with only one patient (5%) experiencing life-threatening haemorrhage. Despite these improvements, in-hospital mortality remained high (n = 5, 24%). No deaths occurred within three months post-discharge. Conclusions: Despite being in its early stages, CDT showed encouraging results in improving hemodynamic and clinical parameters in intermediate-high-risk and high-risk acute PE patients. Larger trials are warranted to further evaluate its efficacy and establish its role in treatment protocols. Background (PE morbimortality limited underdiagnosis Catheterdirected Catheter directed (CDT highrisk risk Objectives intermediatehighrisk intermediate Methods singlecentre single centre 201 202 demographics presentation characteristics outcomes out twosided two sided Students Student s Ttest T test McNemars McNemar Pvalue P value 005 0 05 0.0 Results 2 625 62 5 62. ±16.8 168 16 8 (±16.8 57 n 12 female n=18, n18 18 (n=18 86%, 86 86% , 86%) 75% 75 (75% 25% 25 (25% 57%, 57%) 9 45%, 45 45% 45%) 40%, 40 40% 40%) 4 20%, 20 20% 20%) n=3, n3 3 (n=3 14% 14 comorbidities 35 3. IQR 1.2–4.0. 1240 1.2–4.0 . 1 1.2–4.0) Twothirds Two thirds 10 67% 67 fibrinolysis onethird third 33% 33 thrombolysis RV (RV 72.2% 722 72 (72.2 235 23 23.5% p=0.008. p0008 p p=0.008 008 p=0.008) complications 5% (5% lifethreatening life threatening haemorrhage improvements inhospital hospital 24%. 24 24% 24%) postdischarge. postdischarge post discharge. discharge post-discharge Conclusions stages protocols 00 0. 6 ±16. (±16. n=18 n1 (n=1 7 (75 (25 n=3 (n= 124 1.2–4. 72.2 (72. 23.5 p000 p=0.00 (5 ±16 (±16 n=1 (7 (2 n= 1.2–4 72. (72 23. p00 p=0.0 ( ±1 (±1 1.2– p0 p=0. ± (± 1.2 p=0 1. p=