MEDICINE
CARDIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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to. Its normal duration is from 0.12” to 0.20”
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b. Durations greater than 0.20” indicate atrioventricular block
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c. Durations less than 0.10” indicate Wolf Parkinson White Syndrome
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THAT
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Detailed explanation-1: -The first measurement is known as the “P-R interval” and is measured from the beginning of the upslope of the P wave to the beginning of the QRS wave. This measurement should be 0.12-0.20 seconds, or 3-5 small squares in duration.
Detailed explanation-2: -The PR interval is normally between 0.12 and 0.20 seconds. A PR interval consistently longer than 0.20 seconds, or greater than five small boxes, indicates a first degree AV block.
Detailed explanation-3: -First-degree atrioventricular (AV) block is a condition of abnormally slow conduction through the AV node. It is defined by ECG changes that include a PR interval of greater than 0.20 without disruption of atrial to ventricular conduction. This condition is generally asymptomatic and discovered only on routine ECG.
Detailed explanation-4: -The PR interval is the time from the onset of the P wave to the start of the QRS complex. It reflects conduction through the AV node. The normal PR interval is between 120 – 200 ms (0.12-0.20s) in duration (three to five small squares).