Abstract Funding Acknowledgements Type of funding sources: None. Background Acute coronary syndromes (ACS) are frequent and ventricular tachycardia (VT) is a common and undesiring event in the first hours. Nevertheless, after the first 48 hours VT was associated to worst outcome and complications to short and long term. Purpose Evaluate predictors of VT after the first 48 hours of an ACS. Methods Multicenter retrospective study with patients admitted from October 2010 to September 2019. Patients were divided in two groups (G): G1 – patients with VT in the first 48h, and G2 – patients that presented VT after the first 48 hours of an ACS. VT was defined as a register or more of the VT with at least 30 seconds. Were excluded patients without a previous cardiovascular history or clinical data. Logistic regression was performed to assess predictors of VT after the first 48 hours of an ACS. Kaplan-Meier test was then performed in VT patients to establish the survival rates and cardiovascular admission for one year. Results 29851 patients had ACS, 342 of them had VT, 251 in G1 (73.4%) and 91 in G2 (26.6%). Both groups were similar regarding gender and cardiovascular risk factors, except for stroke (6.8 vs 14.4%, p=0.028). G2 had more patients with more than 75 years (36.3 vs 52.7%, p=0.006)) and had more frequent exhibited >120 minutes from the onset of symptoms until the admission (44.4 vs 66.7%, p=0.001), but was less admitted directly to the cat lab (24.8 vs 10.1%, p=0.003). At admission presented higher levels of non-ST-segment elevation myocardial infarction (23.1 vs 35.2%, p=0.025), several previous episodes of chest pain (27.7 vs 41.7%, p=0.043), Killip-Kimball classification > I (35.5 vs 52.2%, p=0.005) and atrial fibrillation at admission (12.4 vs 21.1%, p=0.045). Ivabradine (5.7 vs 14.6%, p=0.008), aldosterone receptor antagonists (18.0 vs 40.1%, p<0.001), diuretic (47.8 vs 80.0%, p<0.001), insulin (23.5 vs 46.7%, p<0.001) were more prevalent used on VT after the 48h. G2 showed higher values of a non-identifiable culprit lesion (6.9 vs 18.6%, p=0.007) and left ventricular ejection fraction <30% (15.4 vs 32.9%, p<0.001). On the other hand, new-onset heart failure (34.7 vs 19.1%, p=0.006) and atrioventricular block (15.7 vs 1.1%, p<0.001) were higher on G1. G2 showed higher hospitalization death rates (20.9 vs 44.0%, p<0.001). Logistic regression revealed that >120 minutes from the onset of symptoms until the admission (odds ratio (OR) 2.91, p=0.001, confidence interval (CI) 1.57-5.40), ivabradine (OR 2.59, p=0.005, CI 1.00-6.72), diuretic (OR 3.07, p=0.001, CI 1.55-6.08) and insulin (OR 2.38, p=0.007, CI 1.27-4.47) as predictors of VT after the first 48 hours. Mortality rates and cardiovascular hospitalization significantly increase at one year of follow up, with a Kaplan-Meier test of p=0.047 and p=0.008. Conclusions More than 120 minutes from the onset of symptoms until the admission, ivabradine, diuretic and insulin were predictors of VT after the first 48 hours of an ACS.