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Conduction: Difference between revisions
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→The PQ interval
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The PQ interval (sometimes referred to as the PR interval as a Q wave is not always present) indicates how fast the action potential is transmitted through the AV node (atrioventricular) from the atria to the ventricles. Measurement should start at the beginning of the P wave and end at the beginning of the QRS segment. | The PQ interval (sometimes referred to as the PR interval as a Q wave is not always present) indicates how fast the action potential is transmitted through the AV node (atrioventricular) from the atria to the ventricles. Measurement should start at the beginning of the P wave and end at the beginning of the QRS segment. | ||
'''The normal PQ interval is between 0.12 and 0. | '''The normal PQ interval is between 0.12 and 0.22 seconds'''. | ||
A prolonged PQ interval is a sign of a degradation of the conduction system or increased vagal tone (Bezold-Jarisch reflex), or it can be pharmacologically induced. | A prolonged PQ interval is a sign of a degradation of the conduction system or increased vagal tone (Bezold-Jarisch reflex), or it can be pharmacologically induced. | ||