1. What is the RR Interval?

The RR interval is the time between successive R waves on an ECG, representing the duration between heartbeats. It's measured in seconds and is inversely proportional to heart rate.

2. How Does the Calculator Work?

The calculator uses the heart rate formula:

Where:

• \( HR_{bpm} \) — Heart rate in beats per minute
• \( RR_{seconds} \) — RR interval duration in seconds

Explanation: Since there are 60 seconds in a minute, dividing 60 by the RR interval gives the number of heartbeats that would occur in one minute.

3. Importance of Heart Rate Calculation

Details: Accurate heart rate calculation from RR intervals is essential for ECG interpretation, assessing cardiac function, and monitoring patients in clinical settings.

4. Using the Calculator

Tips: Enter the RR interval in seconds (typically between 0.3-1.5 seconds for normal heart rates). The value must be greater than 0.

5. Frequently Asked Questions (FAQ)

Q1: What is a normal RR interval?
A: For a heart rate of 60-100 bpm, normal RR intervals range from 0.6-1.0 seconds.

Q2: How do I measure RR interval from an ECG?
A: Measure the distance between consecutive R wave peaks on the ECG strip, then convert to seconds based on paper speed (typically 25 mm/s).

Q3: What if I have RR interval in milliseconds?
A: Convert milliseconds to seconds by dividing by 1000 before entering the value (e.g., 800 ms = 0.8 seconds).

Q4: Can this be used for irregular heart rhythms?
A: For irregular rhythms like atrial fibrillation, average several RR intervals for a more accurate heart rate estimation.

Q5: What's the relationship between RR interval and heart rate?
A: They have an inverse relationship - as RR interval increases (slower rhythm), heart rate decreases, and vice versa.