Why the Same SEVR Value May Show Up as “Within Range” or “Below Range”

If you’ve noticed that your Subendocardial Viability Ratio (SEVR) appears in different categories—such as “Within Range” one day and “Below Range” the next—even when the number is the same, you’re not alone. Here’s what’s going on and why it matters. 

SEVR Ranges Are Heart Rate Dependent 

SEVR is a dynamic measurement that evaluates the balance between the oxygen supply to your heart and its demand. Importantly, SEVR is influenced by your heart rate at the time of measurement. This means that the same SEVR value could fall into a different reference range depending on how fast your heart was beating during that reading. 

For example, a SEVR of 105% may be considered “Within Range” at a heart rate of 60 bpm but “Below Range” at 75 bpm due to how demand increases as heart rate rises. 

Learn more about SEVR and what your results mean 

Why This Matters 

This approach ensures that your SEVR results are evaluated in the context of your body’s actual physiological state—not just a fixed number. It helps provide a more accurate picture of how your heart is functioning under varying conditions. 

Why You May See Seemingly Conflicting Results 

It’s possible to have two different readings with: 

• The same SEVR value
• Different result categories ("Within Range" vs. "Below Range") 

This is not a bug or error. It’s a reflection of how SEVR reference ranges are personalized and responsive to your heart rate. 

We understand this may be confusing at first, and we're actively working to improve how this information is displayed in future app updates.