DAPT score (Dual Antiplatelet Therapy Score) was developed to dichotomize patients after percutaneous coronary intervention [PCI] into those who will benefit from prolonged DAPT (score 2 or more) and those who are more likely to be harmed by DAPT (score less than 2). A recent study evaluated DAPT with aspirin and clopidogrel given for 2 years vs 6 months in 1970 patients undergoing PCI . Primary efficacy outcomes were death, myocardial infarction or cerebrovascular accident. Primary safety outcome was significant bleeding. In this retrospective study they concluded that prolonged DAPT resulted in harm in patients with low DAPT scores, but reduced ischemic events in those with high scores.
DAPT score is calculated as follows: Age 75 years or more: -2, age 65 – 75 years: -1, age below 65 years: 0, current smoker, diabetes mellitus, myocardial infarction (MI) at presentation, prior PCI or MI, stent diameter less than 3 mm and paclitaxel-eluting stent – 1 each, congestive heart failure or left ventricular ejection fraction less than 30% and saphenous vein graft PCI 2 each . Total score can range from -2 to 10 points.
The score was developed using the data from nearly 12 thousand participants of DAPT study from 11 countries and validated using data from PROTECT trial which had over 8100 patients from 36 countries. Score below 2 is associated with unfavourable benefit/risk ration for prolonged dual antiplatelet therapy while scores of 2 and above have a favourable benefit/risk ratio. This has been further endorsed by ACC/AHA focused update in 2016 .
Decision based on DAPT score to extend beyond 1 year is taken at the end of an uneventful 12 month DAPT.
Piccolo R, Gargiulo G, Franzone A, Santucci A, Ariotti S, Baldo A, Tumscitz C, Moschovitis A, Windecker S, Valgimigli M. Use of the Dual-Antiplatelet Therapy Score to Guide Treatment Duration After Percutaneous Coronary Intervention. Ann Intern Med. 2017 Jul 4;167(1):17-25.
Yeh RW et al; DAPT Study Investigators. Development and Validation of a Prediction Rule for Benefit and Harm of Dual Antiplatelet Therapy Beyond 1 Year After Percutaneous Coronary Intervention. JAMA. 2016 Apr 26;315(16):1735-49.
Levine GN et al. 2016 ACC/AHA Guideline Focused Update on Duration of Dual Antiplatelet Therapy in Patients With Coronary Artery Disease: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines: An Update of the 2011 ACCF/AHA/SCAI Guideline for Percutaneous Coronary Intervention, 2011 ACCF/AHA Guideline for Coronary Artery Bypass Graft Surgery, 2012 ACC/AHA/ACP/AATS/PCNA/SCAI/STS Guideline for the Diagnosis and Management of Patients With Stable Ischemic Heart Disease, 2013 ACCF/AHA Guideline for the Management of ST-Elevation Myocardial Infarction, 2014 AHA/ACC Guideline for the Management of Patients With Non-ST-Elevation Acute Coronary Syndromes, and 2014 ACC/AHA Guideline on Perioperative Cardiovascular Evaluation and Management of Patients Undergoing Noncardiac Surgery. Circulation. 2016 Sep 6;134(10):e123-55.