Original title: Development and Validation of a Stent Thrombosis Risk Score in Patients With Acute Coronary Syndromes. Reference: George D. Dangas et al. J Am Coll Cardiol Intv 2012;5:1097–105.

The implantation of a stent in a pro thrombotic condition such as acute coronary syndrome (ACS) is associated with a higher incidence of stent thrombosis. 

There is no data available in the literature about a validated score that can predict the risk in an individual patient. The aim of this study was to develop and validate a risk score of thrombosis in patients with ACS based on data from the HORIZONS-AMI and ACUITY trials. 

We included 2,986 patients in the analysis of the HORIZONS-AMI and 3,153 for ACUITY, both were randomized 2:1 to develop the score (4,093 patients) or to validate it (2,046 patients). They were followed for one year for the primary analysis and three years for the secondary. Most patients received at least one pharmacological stent, (81.4%). The Academic Research Consortium criteria were utilized for stent thrombosis considering only definite or probable thrombosis. Based on the above, a score model was developed. 

The performance of the model was tested through c-statistic, (0.67 for the development cohort and 0.66 for validation). The score was arbitrarily divided into 3 categories: low risk (1-6 points / 1.65%), intermediate risk (7-9 points / 2.77%) and high risk (≥ 10/6, 45%). At 3 year follow-up, including the very late thrombosis, the risk model remained unchanged, (c-statistic = 0.69).

Conclusion 

The individual risk of stent thrombosis in patients admitted for ACS can be calculated through a simple risk score.

Editorial Comment:

The score to predict the risk of stent thrombosis is practical and can be incorporated into daily clinical practice. It was developed and validated in a specific population with ACS, using (or not) bivalirudin and performed angioplasty using drug eluting stents (most). Although this study showed no association between the type of stent implanted and thrombosis, some previously published studies show a higher incidence of very late thrombosis in drug-eluting stents. There is also the difficulty to transfer the data to our reality as in many countries, such as Brazil, bivalirudin is not yet available. It is necessary to externally validate the score because even in this population, its predictive power was not as high, (c-statistic = 0.66).

Courtesy of Dr. Lucas Lodi-Junqueira
Editorial Board Member

Dr. Lucas Lodi-Junqueira