Thrombosis Research Institute (TRI) has launched the GARFIELD-AF Risk Calculator, an innovative tool for aiding clinician decision making in treating patients with newly diagnosed atrial fibrillation (AF). The tool utilizes individual patient factors to contribute to a clinical prognosis via easily interpretable risk scores, and its ability to estimate rates of stroke, major bleeding, and mortality according to different treatment options is a unique feature.
Challenges in AF
Up to one third of the highest-risk patients are not anticoagulated, whereas many patients with very low stroke risk are. To address the gap, TRI has developed a risk tool to calculate risk rapidly; in a single calculation, clinicians can make more informed, evidence-based decisions.
Modelling and validation
Originally conceptualized from the data of nearly 40,000 GARFIELD-AF participants over 1 year1, the calculator uses data from over 52,000 patients over 2 years. This performed well in comparison with standard AF risk tools CHA2DS2-VASc and HAS-BLED at predicting 2-year mortality, and was externally validated in the ORBIT-AF registry.
Importance of actual values
A further challenge for clinicians is that simplified risk scores often use binary decisions (heart failure, advanced age) but the underlying risk factors have a continuous relationship with hazard, and this may be non-linear (heart rate, blood pressure). Furthermore, when a measure is converted into categories, the score implies everyone in that category has the same level of risk. Clinical lead Professor Keith Fox explained: "The GARFIELD-AF Risk Calculator maintains the actual values of age, weight, pulse and blood pressure, and shows differences in outcomes with treatment selection across two years."
The GARFIELD-AF Risk Calculator is freely available to use, currently hosted on the registry website, with a forthcoming app version to be widely distributed and promoted for clinical adoption on QxMD.
GARFIELD-AF is a worldwide observational registry that aims to enhance the understanding of stroke prevention in atrial fibrillation (AF), under the auspices of TRI, London, UK.
1. Fox KAA, et al. Improved risk stratification of patients with atrial fibrillation: an integrated GARFIELD-AF tool for the prediction of mortality, stroke and bleed in patients with and without. BMJ Open. 2017; Dec 21;7(12):e017157.