Enter the body surface area (BSA), age, and sex into the calculator to estimate the predicted aortic root diameter. This calculator provides an approximate predicted aortic root diameter based on a commonly used adult echocardiography reference equation.
Educational use only; not medical advice. This tool does not diagnose aneurysm or other disease, and it cannot determine normal vs abnormal. Aortic root size must be measured and interpreted by a qualified clinician using appropriate imaging technique and clinical context. Do not delay or avoid medical care based on this tool. Seek urgent care for severe chest/back pain, fainting, sudden shortness of breath, or other severe symptoms.
Who this calculator is (and is not) for
- Intended for: adults using the same kind of “reference equation” approach used in adult echocardiography to estimate a predicted (reference) aortic root diameter from age, sex, and body size.
- Not validated for: children/adolescents, pregnancy, known aortopathy (e.g., Marfan syndrome, Loeys-Dietz), bicuspid aortic valve, known aneurysm, prior aortic surgery, or acute symptoms. In these cases, rely on your clinician’s measurements and guideline-based thresholds.
Measurement and interpretation notes
- Different labs and guidelines may measure the aortic root at different levels (e.g., annulus vs sinuses of Valsalva) and use different conventions (timing in the cardiac cycle, edge-to-edge method). Results may not match your report unless the same convention is used.
- This equation is commonly attributed to adult echocardiography reference literature (often cited to Devereux and colleagues). For applicability details (population, measurement definition, and method), consult the original publication and current echocardiography measurement guidelines (e.g., American Society of Echocardiography guidance).
- This calculator provides a predicted reference diameter only; it does not provide a z-score, standard deviation, or diagnostic threshold.
Aortic Root Diameter Formula
The following formula is used to estimate the aortic root diameter (adult reference equation):
ARD = 24.23 + (4.61 * BSA) + (0.09 * Age) - (2.67 * SexCode)
Variables:
- ARD is the predicted aortic root diameter (mm)
- BSA is the body surface area (m²)
- Age is the age of the individual (years)
- SexCode is 1 for male and 2 for female
To estimate the aortic root diameter, start with 24.23 mm, add 4.61 times the body surface area, add 0.09 times age in years, and subtract 2.67 times the sex code (1 for male, 2 for female).
What is Aortic Root Diameter?
The aortic root diameter is a measurement of the width of the aortic root, the portion of the aorta that is attached to the heart. This measurement is used by clinicians as part of evaluating and managing conditions such as aortic aneurysms and other cardiovascular diseases. The size of the aortic root can vary based on body size, age, and sex, and it is important to have an accurate measurement using the same convention as your imaging lab.
How to Calculate Aortic Root Diameter?
The following steps outline how to calculate the Aortic Root Diameter:
- First, determine the body surface area (BSA) in square meters (m²).
- Next, determine the age of the individual in years.
- Determine sex (male or female).
- Use the formula ARD = 24.23 + (4.61 * BSA) + (0.09 * Age) – (2.67 * SexCode) to estimate the aortic root diameter.
- Finally, calculate the Aortic Root Diameter (ARD) in millimeters (mm).
- After inserting the variables and calculating the result, check your answer with the calculator above.
Example Problem:
Use the following variables as an example problem to test your knowledge.
Body Surface Area (BSA) = 1.7 m²
Age = 45 years
Sex = Male (SexCode = 1)
ARD = 24.23 + (4.61 × 1.7) + (0.09 × 45) − (2.67 × 1) = 33.45 mm (approximately)
