Funding Acknowledgements Type of funding sources: None. Introduction Acute pulmonary embolism (PE) is the third cause of cardiovascular mortality, right after acute myocardial infarction and stroke. Systemic thrombolytic therapy (SLT) restores pulmonary perfusion earlier than low molecular-weight heparin, but with a significantly higher risk of major bleeding. Currently, in our area there is a lack of standardized protocols for the management of patients in which SLT is contraindicated.  Objective The purpose of our study was to evaluate the safety and efficacy of percutaneous catheter-directed treatment (PCT) for high-intermediate risk PE (HIRPE) patients with hemodynamic deterioration on anticoagulation treatment. Methods We consecutively included all patients with HIRPE patients who underwent PCT in our center. Before and after PCT clinical, echocardiographic and hemodynamic variables were collected, as well as events (major or minor bleeding, death) during follow-up. Results From February 2018 to February 2020, 20 patients with HIRPE underwent PCT. The mean age of our cohort was 62 (52 - 73), and 46.6% were women. The indication for PCT was absolute contraindication for SLT (9 patients, 45%), followed by high bleeding risk (8 patients, 40%) and failure of SLT. Vascular access was mainly performed through femoral vein (12 patients, 60%) followed by a peripheral vein of the superior limb (8 patients, 40%). During pulmonary angiography, lobar arteries occlusion was observed in 60% of the cases, with involvement of main pulmonary arteries in 40% of the cases. Local thrombolysis with Alteplase was performed in 17 cases (85%), and in 8 cases it was decided to carry-out a thrombus fragmentation-aspiration strategy. We observed and early improvement of hemodynamic parameters after PCT, with a significant reduction of mean pulmonary artery pressure before and after PCT (40 +/- 13 mmHg vs. 25 +/- 12 mmHg, p < 0.001, figure 1), as well as an improvement in systolic blood pressure (102 +/- 13 mmHg vs. 129 +/- 14, p < 0.001) and the partial pressure of oxygen (51 +/- 3 vs. 67 +/- 2, p = 0.002). We also observed a significant decrease in NT-proBNP values at admission and 48 hours after PCT (4791 +/- 1077 pg/mL vs. 2311 +/- 680 pg/mL, p = 0.002, figure 2), as well as an improvement in echocardiographic right ventricular function parameters evaluated at admission and 72 hours after PCT, such as TAPSE (15 +/- 2 mm vs 22 +/- 3 mm, p = 0.001) or right ventricle basal diameter (51 +/- 4 mm vs. 41 +/- 2 mm, p = 0.001). During a median follow-up of 7 months (4 - 12 months) one patient died of non-cardiac cause and none of them had a major or minor bleeding event. Conclusion PCT in patients with HIRPE with hemodynamic deterioration on anticoagulation is a simple and effective procedure with an immediate reduction of mean pulmonary pressure and an early improvement of right ventricle-related biochemical, hemodynamic and echocardiographic parameters. Abstract Figure 1: mPAP after and before PCT.

Funding Acknowledgements Type of funding sources: None. Introduction Inflammation may play an important role in the development of atrial fibrillation (AF). Some studies have suggested that cancer through inflammatory mediators may promote the development of AF (1-2). Our hypothesis was that patients with a first episode of AF might be at increased risk of developing cancer. We set out to study the incidence of cancer in the 2 years following a first episode of AF and to investigate the differences between patients (pts) who develop malignancies and those who do not. Methods Clinical and analytical data were collected from pts presenting with an episode of AF, diagnosed electrocardiographically, to the Emergency Department of our hospital in Spain between 2010-2015 (n=2013). After selecting pts with a first episode and excluding pts with a history of AF or cancer and those with an identified precipitating factor, a sample of 712 pts was obtained (mean age 74.3±14.7; 61.9% female). The minimum follow-up was 2 years, registering cancer occurrence and type, total mortality, emergency department attendance and hospitalization for cardiovascular causes, AF recurrences as well as bleeding and embolic events. We compared data from those who developed cancer during the 2 years after AF debut with those who did not, as well as with the incidence and types of cancer in the general population in Spain (SP) in 2012 (3). Results Of the 712 patients, 35 patients (4.91%) were diagnosed with cancer during the 2-year follow-up (annual incidence: 2.45% (sample) vs 0.46% (SP); p<0.01). The annual incidence in our <65 years old sample was 0.28% vs 0.18% in SP; p<0.05. In the >65 years old group, annual incidence was 2.17% (sample) vs 0.28% (SP); p<0.01. There were also differences between cancer types, with non-solid neoplasms being more frequent in our sample (34.28%), followed by colorectal and breast (14.28% both) (Figure 1). In multivariate analysis comparing patients with and without cancer in our sample, occurrence of cancer was only associated with non-typical symptoms (absence of palpitations) : 33.38% vs 14.28%; p<0.05, and lower creatinine levels in patients developing cancer. Multiple correspondence analysis (MCA) also found no variables associated with cancer development (Figure 2). The mortality rate was higher in the group that developed cancer (54.28% vs 36.02%, p<0.05), with no significant differences in the remaining events. Conclusions There is a relatively high incidence of cancer in patients with a first episode of AF (annual incidence of 2.45% after AF debut is 6.1 times the risk in the general population), in particular in the group of age > 65 years old. No relevant clinical or analytical variable was able to predict the patient who will develop cancer. Further studies and exploration of new variables are needed to better assess the association between AF and cancer occurrence.