The Relationship Between Dual Antiplatelet Treatment Score and Thrombus Burden in Patients with Acute Myocardial Infarction

Objectives: High thrombus burden (HTB) was an independent predictor of death, repeat myocardial infarction, and infarct-related artery intervention and stent thrombus in patients with acute myocardial infarction (AMI). This study aimed to evaluate the predictive role of the dual antiplatelet therapy (DAPT) score in the estimation of intracoronary thrombus burden in patients with AMI. Materials and Methods: Between March 2020 and May 2020, 360 consecutive patients admitted with AMI who underwent coronary angiography at the cardiology department of our institution were retrospectively evaluated. The DAPT score has been defined as previously in the DAPT study. The thrombolysis in myocardial infarction (TIMI) thrombus grade was calculated for each patient from the diagnostic angiographic images taken before percutaneous coronary interventions. HTB was defined as TIMI thrombus grades 4 and 5 calculated according to the TIMI thrombus grading scale. The study population was divided into two groups according to their TIMI thrombus grade: low thrombus burden (LTB) (TIMI 0-3) and HTB (TIMI 4 and 5). Results: There were 133 patients (36.9%) in the LT group and 227 patients (63.1%) in the HTB group. Patients with HTB had significantly a higher DAPT score (p=0.010) compared with LTB patients. The ability of the DAPT score to predict the HTB was evaluated by receiver operating characteristic curve analysis. The cut-off value of the DAPT score for predicting the HTB was 2 (with a sensitivity of 67.8%, specificity=69.4%) according to the Youden index. Univariate regression analysis demonstrated that the DAPT score was significantly associated with the HTB. On multivariate analysis, the DAPT score (Odds ratio: 1,245, 95% confidence interval: 1,009-1,537; p=0.041) was found as an independent predictor of the HTB when the DAPT score was analyzed as a continuous variable. Conclusion: The DAPT score is a practical score system to guide DAPT duration, accounting for both ischemic risk and bleeding risk factors. Considering the increasing number of patients with acute coronary syndromes, prediction of thrombus burden through a simple and practical scoring system may be of benefit. Keywords: Acute myocardial infarction, DAPT score, percutaneous coronary intervention, thrombus burden