Supraventricular tachycardia electrocardiogram

The best method to diagnose supraventricular tachycardia is through electrocardiography. Presentation on EKG will vary depending on the subtype. In general, QRS complexes tend to be tall and narrow, P waves are absent, and rate is greater than 100 beats per minute. Asystole may occur due to tachycardia-mediated suppression of the sinus node when the rhythm is in AVNRT.

Shown below is an EKG example of supraventricular tachycardia. The heart rate is around 185 bpm. It is somewhat unusual presentation for someone with angina. The arrhythmia terminated with adenosine which has a powerful cholinergic effect that blocks conduction through the AV node.

Copyleft image obtained courtesy of ECGpedia, http://en.ecgpedia.org/wiki/File:E345.jpg

Shown below is an EKG depicting a tachycardia at a rate of 190/min with narrow QRS complexes indicating supraventricular tachycardia.

Copyleft image obtained courtesy of ECGpedia, http://en.ecgpedia.org/wiki/File:De-AW00011.jpg

Shown below is an EKG recording of a patient who goes from sinus rhythm to a wide complex tachycardia at about 130/min. The wide QRS though disappears after nine complexes and is replaced by narrow complexes at a slightly slower rate. No P wave activity is seen. This is a supraventricular tachycardia with a form of aberrancy. In this case we are probably seeing a rate dependent left bundle branch block or the effect of a left bundle branch block which persists for the nine complexes because of continued block in the left bundle from the depolarizations from the intact right bundle.

Copyleft image obtained courtesy of ECGpedia, http://en.ecgpedia.org/wiki/Main_Page

Shown below is an example of a EKG demonstrating a rapid heart rate at the rate of nearly 300 beats per minute indicating a paroxysmal supraventricular tachycardia.

Copyleft image obtained courtesy of ECGpedia, http://en.ecgpedia.org/wiki/File:De-AW00012.jpg

For more EKG examples of supraventricular tachycardia, click here

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