1. What is RR Interval?

The RR interval is the time between successive R waves on an electrocardiogram (ECG). It represents the duration of one cardiac cycle and is used to assess heart rate variability and rhythm.

2. How Does the Calculator Work?

The calculator uses the RR interval equation:

Where:

• \( RR_{ms} \) — RR interval in milliseconds
• \( HR \) — Heart rate in beats per minute (bpm)

Explanation: The equation converts heart rate (beats per minute) to the duration of one cardiac cycle (milliseconds).

3. Importance of RR Interval Calculation

Details: RR interval measurement is essential for assessing heart rate variability, diagnosing arrhythmias, and evaluating autonomic nervous system function.

4. Using the Calculator

Tips: Enter heart rate in bpm. The value must be valid (HR > 0). The calculator will compute the corresponding RR interval in milliseconds.

5. Frequently Asked Questions (FAQ)

Q1: What is a normal RR interval?
A: Normal RR interval varies with heart rate. At 60 bpm, RR is 1000 ms. It decreases with higher heart rates and increases with lower heart rates.

Q2: How is RR interval related to heart rate?
A: RR interval is inversely proportional to heart rate. As heart rate increases, RR interval decreases, and vice versa.

Q3: Why measure RR interval in milliseconds?
A: Milliseconds provide precise timing measurements needed for analyzing cardiac rhythms and heart rate variability.

Q4: What affects RR interval variability?
A: Breathing, autonomic nervous system activity, medications, and various physiological and pathological conditions.

Q5: Can this calculator be used for arrhythmias?
A: This calculates average RR interval for regular rhythms. For irregular rhythms, direct ECG measurement is needed.