Supraventricular Tachycardias: How to Diagnose the Mechanism
Supraventricular tachycardias are a very common clinical condition. In this chapter, we analyze few supraventricular tachydardia 12-lead EKGs to discover their underlying mechanism.
At first, we have to observe the rhythm regular pattern. If regular, we have to check for P (or F) waves. If a P wave is visible, we have to assess the P/QRS ratio. When atrial activity is faster than the ventricular, we may consider the atrial flutter or atrial tachycardia hypothesis.
When P/QRS ratio is 1:1, we have to consider a possible reentrant circuit between atria and ventricles. Then, assessing RP and PR intervals, we can identify the mechanism of the tachycardia and make the correct diagnosis.
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