This ECG has both second degree AV block with 2:1 block and second degree type I AV block. Note that intermittent P waves conduct to the ventricles on this ECG tracing, however it is clear that ...

A first-degree, or 1 st degree, AV block is indicated on the ECG by a prolonged PR interval, as seen below. Recall that the P wave indicates atrial depolarization, initiated by firing of the SA node.

Upon review of this body and the described ECG findings, certain common patterns ... consisting of various degrees of AVB, and no clear case of PR interval shortening, were found.

She returns for a follow-up visit for palpitations, and a 12-lead ECG is obtained ... Therefore, the rhythm is atrial flutter with 2:1 AV block. Importantly, the only supraventricular rhythm ...