Funding Acknowledgements Type of funding sources: None. Main funding source(s): None Background Sleep apnea is a known risk factor for atrial fibrillation recurrence after catheter ablation. Despite this, in recent atrial fibrillation guidelines, it is unclear in which patients to test sleep apnea before catheter ablation. Purpose Evaluate if body mass index (BMI) has a good discriminative power to predict sleep apnea in patients with atrial fibrillation proposed to catheter ablation. Methods We retrospectively studied 160 consecutive patients undergoing catheter ablation of paroxysmal or persistent atrial fibrillation in our institution. We evaluated recurrence of atrial fibrillation after catheter ablation and analysed diagnosis of sleep apnea, body mass index, treatment with CPAP, echocardiographic findings (indexed volume of left atrium and left ventricular ejection fraction), cardiovascular risk factors and other comorbidities and clinical characteristics. Receiver operator characteristics (ROC) curve and area under the curve (AUC) were obtained to determine the discriminative power of body mass index as predictor of sleep apnea. Optimal cut-point value was obtained (Youden index) and patients were divided according to this value. Results During a mean follow-up time of 22,8 ± 19,9 months, 46 patients (28,8%) had atrial fibrillation recurrence and none died. The recurrence was associated with hypertension, alcohol habits and untreated sleep apnea (HR 3,74; 95% CI 1,89-7,42; p <0,001). Optimal cut-point value for predicting sleep apnea in patients with atrial fibrillation proposed to catheter ablation was BMI of 28,0 Kg/m2 (AUC 0,733, p = 0,001, 95% CI 0,640-0,827). The group of patients with BMI of 28,0 Kg/m2 had a 4-fold increased risk of sleep apnea (OR 3,95, 95% CI 1,85-8,42, p =0,001) and 2-fold risk of atrial fibrillation recurrence (HR 1,96; 95% CI 1,10-3,51; p = 0,023). Conclusions In this group of patients undergoing catheter ablation of atrial fibrillation, a BMI ≥ 28,0 Kg/m2 was independent predictor of sleep apnea and recurrence of atrial fibrillation after catheter ablation. In patients with atrial fibrillation proposed to catheter ablation and BMI ≥ 28,0 Kg/m2 is reasonable to do a sleep study before catheter ablation.

Background Coronavirus disease 2019 (COVID-19) has been associated with significant morbidity and mortality, with cardiovascular involvement being usual. Elevations in cardiac Troponin-I level has proposed as an independent biomarker for mortality among patients with COVID-19. Aim To evaluate the role of high sensivity Troponin-I (hs-TnI) level at hospital admission in predicting 30 day in-hospital mortality and 6-month mortality in patients hospitalized with a COVID-19 diagnosis. Methods We performed a retrospective single-center cohort study including consecutive patients aged 18 years and older who were admitted for COVID-19, during a 1-year period (n=818). We excluded patients with acute coronary syndrome (n=23), patients with acute heart failure (n=42), and patients in which hs-TnI level was not dosed at admission (n=163). Patients were divided into two groups according to hs-TnI levels: hs-TnI <19.8 vs hs-TnI ≥19.8 pg/mL. Primary outcomes were 30-day in-hospital mortality and 6-months mortality. According to the data distribution, appropriate statistical tests were conducted to compare independent samples. Multivariable logistic regression was used to analyze mortality risk. Receiver operator characteristics (ROC) curve and area under the curve (AUC) were obtained to determine the discriminative power of hs-TnI as a predictor of mortality. (Figure 1). Results This cohort included 590 patients. Mean age was 71 ≥±15 years and 52.4% were men. Overall, 209 patients (35.4%) had elevated hs-TnI levels and 381 patients had normal hs-TnI levels. Individuals in the hs-TnI ≥19.8 pg/mL group were older (80±11 vs 66±14 years, p<0.001) and presented higher prevalence of chronic heart failure (24.9% vs 7.1%, p<0.001), hypertension (77.0% vs 57.5%, p<0.001), atrial fibrillation/flutter (19.1% vs 5.5%, p<0.001), prior stroke (12.4% vs 5.2%, p=0.001) and ischemic heart disease (12.4% vs 3.7%, p<0.001). There was no difference in length of hospital stay between the groups (8.0 [IQR 9.6] in hs-TnI 19.8 pg/mL group vs 9.0 [IQR 8.0] normal hs-TnI group, p=0.669). Troponin-I was the only independent predictor of in-hospital mortality (OR 3.80, CI 95%: 2.44–5.93, p<0.001), see Table 1. The troponin levels had the highest area under the receiver operating characteristic curv (AUC) with an AUC of 0.705 (95% CI: 0.667–0.742, p<0.001) for association with the in-hospital mortality (figure 1). There was no difference in 6-months mortality between the two groups. Conclusion Acute myocardial injury is common in patients hospitalized with COVID-19. In the present study a TnI level ≥19.8 pg/mL was predictor of 30 days in-hospital mortality, suggesting that raised levels of this biomarker is associated with adverse prognosis. This tool might be useful for COVID-19 patient risk stratification. Further studies are needed to provide robust data and reliable recommendations on this theme. Funding Acknowledgement Type of funding sources: None.

Funding Acknowledgements Type of funding sources: None. Background Cardiovascular disease (CVD) is the most common noncommunicable disease and actually the leading cause of death globally. Hence, it is important to identify individuals who may benefit from CVD preventive strategies. The European Society of Cardiology (ESC) has recently updated the European Systematic Coronary Risk Evaluation (SCORE) to SCORE2 and SCORE2-OP risk prediction algorithms. Those tools were recalibrated to four groups of countries (low, moderate, high and very high CVD risk) based on national CVD mortality rates published by the WHO, with Portugal being now considered a moderate risk country. Purpose To evaluate the application of SCORE2 and SCORE2-OP in a Portuguese population sample. Methods We conducted a cross-sectional study, including individuals aged 40-90 years, without known established Atherosclerotic Cardiovascular Disease, Diabetes mellitus, Chronic Kidney Disease or Familial Hypercholesterolemia. The sample was recruited at a local cardiovascular screening event in Portugal that took place in May 2022. The 10-year fatal and non-fatal CVD risk was calculated using SCORE2 (for individuals aged < 70 years) and SCORE2-OP (for individuals aged ≥ 70 years) tools. Based on CVD risk category, patients were stratified into 3 categories: low to moderate, high and very high risk according to new SCORE algorithms. Primary outcome was the assessment of 10-year risk of fatal and non-fatal CVD with SCORE2 e SCORE2-OP in a local Portuguese population. According to the data distribution, appropriate statistical tests were conducted to compare independent samples. Multivariable linear regression was used to analyze 10-year CVD risk. Results This cohort included 431 individuals. Median age was 71 years (Q1-Q3: 65-75) and 66.8% of individuals were women. Regarding baseline characteristics of the included individuals, 48.1% had hypertension, 38.3% had dyslipidemia, 25.5% were obese and 6.6% were smokers. Based on the SCORE2 model 92 (26.1%) individuals were classified into low to moderate risk, 162 (46.0%) into high risk and 98 (27.8%) into very high-risk category. SCORE2 median was 3.43 % (Q1-Q3: 5.5-8.0 p< 0.01) and SCORE2-OP median was 12.70 % (Q1-Q3: 9.7-12.7). Active smoking was the only independent predictor of 10-years CVD risk both in SCORE2 (RR 3.28, 95% CI: 1.93-4.66, p=0.001) and SCORE2-OP (RR 6.31, 95% CI: 2.67-9.52, p<0.001). Conclusions Most individuals in this sample were stratified into high or very high risk of developing 10-year fatal and non-fatal cardiovascular events. This data is in accordance with the updated risk category of Portugal based on World Health Organization cardiovascular mortality rates. These results not only validate the application of SCORE to the Portuguese setting, but also reinforce how this easily applicable tool can help to identify patients who will benefit from CVD preventive strategies.

Funding Acknowledgements Type of funding sources: None. Background Cardiovascular disease (CVD) risk assessment plays a central role in nowadays clinical practice given its burden in morbidity and mortality worldwide. In the 2021 European Society of Cardiology Guidelines on cardiovascular disease prevention a new CVD risk prediction algorithm was presented, the SCORE2. This tool overcomes some of old SCORE limitations by predicting 10-year fatal and non-fatal CVD risk in individuals without previous CVD or diabetes aged 40-65 years and by including contemporary data from epidemiological data of 13 European countries. Differences on 10-year cardiovascular risk category prediction between SCORE and SCORE2 is still scarce. Purpose We aimed to compare differences in 10-year cardiovascular disease risk prediction in a Portuguese population using SCORE and SCORE2. Methods We conducted a cross-sectional study in a Portuguese population sample. Individuals aged 40-65 years old without known Atherosclerotic Cardiovascular Disease, Diabetes, Chronic Kidney Disease or Familial Hypercholesterolemia were included. The 10-year CVD risk was calculated using SCORE and SCORE2. Based on CVD risk category, patients were stratified into 4 categories - low, moderate, high and very high risk – according to SCORE and in 3 categories - low to moderate, high and very high risk - according to SCORE2 model. Primary outcome was 10-year CVD risk prediction difference between above mentioned models. According to the data distribution, appropriate statistical tests were conducted. Results 117 individuals were included in the study cohort, 79 (67.5%) of which were women. In our study, the 10-year risk prediction of fatal and non-fatal cardiovascular events was significantly different between SCORE and SCORE2. When assessing 10-year risk of CVD through SCORE model, 97.1% (n= 100) of the individuals were classified into low and moderate risk categories. On the other hand, when evaluating CVD risk with SCORE2 only 66% (n=62) of the participants were classified into those risk categories, meaning that 30.9% (n=29) of patients were in high and very high-risk categories with SCORE2 (vs. 2.9% with SCORE). Correlation between SCORE and SCORE2 was verified (R=0.572; p< 0.0001). Regarding cardiovascular risk factors, active smoking was the only independent predictor for 10-year CVD risk in SCORE2 (RR: 3.28, 95% CI: 1.93-4.66, p=0.001). There were no independent predictors for CVD risk in SCORE. Conclusions Ten-year cardiovascular risk assessment may be underestimated by SCORE model. In the present study, through SCORE CVD risk classification most of patients were classified into lower risk categories than those obtained through updated SCORE2. SCORE2 is a more up-to-date and more calibrated CVD risk assessment tool than old SCORE, so SCORE2 may contribute to a better reclassification of patients and hereafter allow intensification of CVD protection measures.

Funding Acknowledgements Type of funding sources: None. Background Obstructive Sleep Apnea (OSA) is a highly prevalent disorder in developed countries. It is well known that OSA is strongly associated with Atrial Fibrillation (AFib) and sinus pauses, but its impact on ventricular arrhythmias is less clear. Purpose The aim of this study was to evaluate the presence of rhythm disorders in 24h Holter in patients with OSA and their association with different grades of OSA severity. Methods We performed a retrospective single-center cohort study. The study included patients who underwent both a level 3 polysomnography and a 24h Holter test at our hospital center between 1 January 2015 and 31 December 2019 (n=464). We excluded patients without OSA, patients with OSA under current treatment with CPAP/APAP and those who only had 24h Holter test after starting CPAP/APAP. Patients were divided into 3 groups according to the OSA severity in the sleep study test: mild, moderate and severe. The Holter was analyzed for the presence of AFib, number of premature atrial contractions (PACs), presence of runs of PACs, number of premature ventricular contractions (PVCs), presence of non-sustained ventricular tachycardia (NSVT) and the presence of conduction disorders. Premature contractions were considered frequent when greater than 30 per hour. These results were compared in the three groups. Results This cohort included 233 patients: 89 classified into mild, 74 into moderate and 70 into severe OSA form. The baseline characteristics of patients are depicted in table 1. The overall median age was 67 (57-73) years and was similar between the groups. Male gender was more prevalent in the overall sample and statistically more prevalent in the severe OSA group (56.2% in mild vs 75.7% in severe OSA, p=0.08). Regarding cardiovascular risk factors, there was no difference between the groups except for obesity, with higher body mass indexes translating into more OSA severity (p=0.049). Results are shown in table 2. We observed that OSA severity and AFib are associated. AFib was more prevalent in the moderate and severe forms of OSA (13.5% in moderate and 18.6% in severe OSA vs. 6.7% in mild OSA; p=0.041). The prevalence of atrioventricular block and the prevalence of intraventricular block were higher in the moderate group of OSA (p=0.048; p=0.007). There was no association between OSA severity and the burden and complexity of PACs. On the contrary, we found a higher percentage of frequent PVCs in more severe forms of OSA (20.3 and 21.4% in moderate and severe group, p=0.031). Conclusion In the present study the severity of OSA was associated with a higher prevalence of AFIb and conductions disorders as expected. However, it was also associated with higher prevalence of frequent premature ventricular contractions but not with atrial premature contractions. Further studies are needed to confirm these findings and to study the benefit of level 3 polysomnography testing in patients with frequent PVCs.