A focused collection of 10 calculators, scores, and clinical references.
ABC Stroke Risk Score: Explanation and Clinical Context The ABC (Age, Biomarkers, Clinical History) Stroke Risk Score is a validated biomarker-based model designed to estimate the individual 1-year risk of ischemic stroke or systemic embolism in patients with atrial fibrillation. It was developed and validated using data from the ARISTOTLE and RE-LY trials (Hijazi et al., Circulation 2016;133:268–277). Unlike traditi
Appraisal of Risk in AF (ARISTOTLE-based) Score: Explanation and Clinical Context The ARISTOTLE-based risk score for atrial fibrillation was developed from the ARISTOTLE trial population to predict 1-year risk of stroke or systemic embolism in patients with AF. The model is based on easily obtainable clinical variables including age, prior stroke or transient ischemic attack (TIA), hypertension, diabetes mellitus, an
ATRIA Bleeding Score: Explanation and Clinical Context The ATRIA Bleeding Score (Anticoagulation and Risk Factors in Atrial Fibrillation) is a validated risk stratification tool designed to estimate the annual risk of major bleeding in patients with atrial fibrillation (AF) receiving oral anticoagulant therapy. Developed from a cohort of over 13,000 AF patients in the ATRIA study, it incorporates five independent pre
C₂HEST Score: Explanation and Clinical Context The C₂HEST Score is a validated clinical tool designed to predict the risk of incident atrial fibrillation (AF) over 5 years. It was derived from a large Asian cohort and subsequently validated in European populations. The acronym C₂HEST represents six risk factors: Coronary artery disease or Chronic heart failure (2 points), Hypertension, Elderly (age >75 years), Systol
CHA₂DS₂-VASc Score: Explanation and Clinical Context The CHA₂DS₂-VASc Score is a validated clinical risk stratification tool used to estimate the annual risk of ischemic stroke in patients with atrial fibrillation (AF), particularly non-valvular AF. It refines the earlier CHADS₂ Score by incorporating additional risk factors—vascular disease, age 65–74 years, and female sex—to improve sensitivity in identifying patie
GARFIELD-AF Risk Model: Explanation and Clinical Context The GARFIELD-AF Risk Model is a validated clinical tool derived from the Global Anticoagulant Registry in the FIELD–Atrial Fibrillation, which captures real-world data on patients with atrial fibrillation worldwide. This model provides individualized predictions for three critical outcomes: ischemic stroke/systemic embolism, major bleeding, and all-cause mortal
HAS-BLED Score: Explanation and Clinical Context HAS-BLED is a validated scoring system designed to assess the 1-year risk of major bleeding in patients with atrial fibrillation who are receiving anticoagulation therapy. It incorporates clinical risk factors including hypertension, abnormal renal or liver function, history of stroke or major bleeding, labile INR, age, concomitant use of drugs that increase bleeding r
HATCH Score (Atrial Fibrillation Progression): Explanation and Clinical Context The HATCH Score is a validated risk assessment tool designed to predict the likelihood of progression from paroxysmal atrial fibrillation (AF) to persistent or permanent AF. Developed from a cohort study by De Vos et al., the score incorporates five key clinical predictors: heart failure, age >75 years, history of transient ischemic attac
ORBIT Bleeding Score: Explanation and Clinical Context The ORBIT Bleeding Score is a validated clinical tool designed to predict the annual risk of major bleeding in patients with atrial fibrillation receiving oral anticoagulant therapy. Developed from the large-scale ORBIT-AF (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation) study, it incorporates five easily available clinical variables: olde
SAMe-TT₂R₂ Score: Explanation and Clinical Context The SAMe-TT₂R₂ score is a validated clinical tool to predict the quality of warfarin anticoagulation control in patients with atrial fibrillation. It integrates demographic and clinical factors including sex, age, comorbidities, concomitant interacting drugs, tobacco use, and race. A score of 0–2 predicts likely good anticoagulation control (time in therapeutic range