Question

The number of QRS complexes observed per
minute in an ECG of a person was 85. What could
be the heart rate of that person during
observation?
(1) 72
(2) 85
(3) 65
(4) 90​

Answer 1

Answer:

Yes 85 is the correct answer

Answer 2

The number of QRS complexes observed per  minute in an ECG of a person was 85. What could  be the heart rate of that person during observation is (2) 85.

Explanation:

• The normal duration (interval) of the QRS complex is between 0.08 and 0.10 seconds.
• That is 80 and 100 milliseconds.
• When the duration is between 0.10 and 0.12 seconds it is intermediate or slightly prolonged. A QRS duration of greater than 0.12 seconds is considered abnormal.
• To measure the QRS interval start at the end of the PR interval (or beginning of the Q wave) to the end of the S wave.
• Normally this interval is 0.08 to 0.10 seconds.
• When the duration is longer it is considered a wide QRS complex.
• When the cardiac rhythm is regular the heart rate can be determined by the interval between two successive QRS complexes.
• On standard paper with the most common tracing settings the heart rate is calculated by dividing the number of large boxes (5 mm or 0.2 seconds) between two successive QRS complexes into 300.