Under 65 years (0 points)
65 – 74 years (1 point)
75 years or older (2 points)
Male (0 points)
Female (1 point)
Total CHA₂DS₂-VASc Score:
0
Understanding the CHA₂DS₂-VASc Score
The CHA₂DS₂-VASc score is a clinical prediction tool used by healthcare professionals to estimate the risk of stroke in patients with non-valvular atrial fibrillation (AFib). This score helps determine whether a patient should receive anticoagulant therapy (blood thinners) to prevent blood clots.
The Scoring System Breakdown
C: Congestive Heart Failure (1 point) – History of heart failure or left ventricular dysfunction.
A₂: Age ≥ 75 years (2 points) – Advanced age is a significant risk factor.
D: Diabetes Mellitus (1 point) – Fasting plasma glucose >125 mg/dL or treatment with oral hypoglycemics/insulin.
S₂: Stroke/TIA (2 points) – History of stroke, transient ischemic attack (TIA), or systemic embolism.
V: Vascular Disease (1 point) – History of myocardial infarction (heart attack), peripheral artery disease (PAD), or complex aortic plaque.
A: Age 65-74 years (1 point) – Moderate risk associated with age.
Sc: Sex Category (1 point for females) – Females have a statistically higher risk of stroke compared to males with similar factors.
Interpreting Your Results
A higher score indicates a higher annual risk of stroke. While guidelines vary by region (e.g., AHA/ACC vs. ESC), general interpretations include:
Score
Risk Level
Typical Recommendation
0 (Male)
Low
No anticoagulation
1 (Male) / 2 (Female)
Intermediate
Consider oral anticoagulation
2+ (Male) / 3+ (Female)
High
Oral anticoagulation recommended
Realistic Example Calculation
Consider a 72-year-old female with a history of hypertension and diabetes:
Age (65-74): 1 point
Sex (Female): 1 point
Hypertension: 1 point
Diabetes: 1 point
Total Score: 4 points
In this scenario, the estimated annual stroke risk is approximately 4.0%, and oral anticoagulation would typically be strongly recommended by a physician.
Disclaimer: This tool is for educational purposes only and does not constitute medical advice. Always consult with a qualified healthcare professional regarding clinical decisions and anticoagulation therapy.
function calculateChads() {
var score = 0;
// Age Score
var ageValue = parseInt(document.getElementById('age').value);
score += ageValue;
// Sex Score
var sexValue = parseInt(document.getElementById('sex').value);
score += sexValue;
// Checkboxes
if (document.getElementById('chf').checked) score += 1;
if (document.getElementById('htn').checked) score += 1;
if (document.getElementById('dm').checked) score += 1;
if (document.getElementById('stroke').checked) score += 2;
if (document.getElementById('vascular').checked) score += 1;
// Risk Mapping (Adjusted stroke risk percentages based on standard data)
var riskMap = {
0: "0%",
1: "1.3%",
2: "2.2%",
3: "3.2%",
4: "4.0%",
5: "6.7%",
6: "9.8%",
7: "9.6%",
8: "12.5%",
9: "15.2%"
};
var resultBox = document.getElementById('result-box');
var scoreDisplay = document.getElementById('final-score');
var riskDisplay = document.getElementById('risk-text');
var recDisplay = document.getElementById('recommendation');
resultBox.style.display = "block";
scoreDisplay.innerText = score;
riskDisplay.innerText = "Estimated Annual Stroke Risk: " + (riskMap[score] || "High Risk");
// Display coloring and recommendation
if (score === 0 || (score === 1 && sexValue === 1)) {
resultBox.style.backgroundColor = "#d4edda";
resultBox.style.color = "#155724";
recDisplay.innerText = "Generally considered low risk. Anticoagulation may not be required.";
} else if (score === 1 || (score === 2 && sexValue === 1)) {
resultBox.style.backgroundColor = "#fff3cd";
resultBox.style.color = "#856404";
recDisplay.innerText = "Intermediate risk. Anticoagulation should be considered based on clinical judgment.";
} else {
resultBox.style.backgroundColor = "#f8d7da";
resultBox.style.color = "#721c24";
recDisplay.innerText = "High risk. Oral anticoagulation is typically recommended.";
}
}