Introduction: Stent thrombosis (ST) is an uncommon, but significant complication following angioplasty. We aimed to examine the predictors, clinical outcomes and mechanism of definite ST cases among patients who underwent percutaneous coronary intervention (PCI). Methods: This was a retrospective observational registry of 14,935 patients from the year 2011 till 2015. Clinical characteristics, clinical outcome and intracoronary imaging data were recorded in all the patients. The SPSS Statistic version 24 was used for statistical analysis. The Cox regression hazard model was used to report calculate the hazard ratio (HR) with a 95% confidence interval (95%CI). Independent predictors of ST were identified by univariate logistic regression analysis. Variables that showed a statistically significant effect in univariate analyses were entered in a multivariate Cox proportional hazards model. A p-value<0.05 was regarded as significant. Results: The incidence of definite ST was 0.25% (37 out of 14935 patients). 75% of ST group patients presented with ST elevation myocardial infarction (75% vs. 19.8%, p<0.01). There was higher mortality among patients with ST when compared to the group without ST (Hazard Ratio, HR=10.69, 95%CI: 1.13, 100). Two independent predictors of ST were 1) previous history of acute myocardial infarction (HR=2.36, 95%CI: 1.19, 4.70) and 2) PCI in the context of acute coronary syndrome when compared to elective PCI (HR=37, 95%CI: 15.7, 91.5). Examination of 19 ST cases with intracoronary imaging identified nine cases (47%) of underexpanded stents and five cases (26%) of malopposition of stents. Conclusions: ST is associated with high mortality. PCI in acute coronary syndrome setting and a previous history of acute myocardial infarction were significant predictors for ST. Intracoronary imaging identified stent underexpansion and malopposition as common reasons for ST. In cases where the risk of ST is high, the use of intracoronary imaging guided PCI is recommended.

Introduction: Atrial fibrillation (AF) is the most commoncardiac arrhythmia with significant morbidity and mortalityin relation to thromboembolic stroke. Our study aimed toevaluate the safety and efficacy of dabigatran in strokeprevention in elderly patient with nonvalvular AF with regardto the risk of ischemic stroke and intracranial haemorrhage(ICH) in real-world setting.Methods: A retrospective cohort study of 200 patients ondabigatran and warfarin from January 2009 till September2016 was carried out. Data were collected for 100 patients ondabigatran and 100 patients on warfarin.Results: The mean follow-up period was 340.7±322.3 daysfor dabigatran group and 410.5±321.2 days for warfaringroup. The mean time in therapeutic range (TTR) was52±18.7%. The mean CHA2DS2 -VASc score for dabigatrangroup was 4.4±1.1 while 5.0±1.5 for warfarin group. None indabigatran group experienced ischemic stroke compared toone patient in warfarin group (p=0.316). There was onepatient in dabigatran group suffered from ICH compared tonone in warfarin group (p=0.316). Four patients in warfaringroup experienced minor bleeding, while none fromdabigatran group (p=0.043).Conclusion: Overall bleeding events were significantly lowerin dabigatran group compared to warfarin group. In thepresence of suboptimal TTR rates and inconveniences withwarfarin therapy, non-vitamin-K antagonist oralanticoagulants (NOAC) are the preferred agents for strokeprevention in elderly Asian patients for nonvalvula