What is the rhythm of this routine EKG?
Answer & Explanation
The clue to this rhythm lies within the compensatory pause following the PVC at the end of the tracing. Notice a P-wave with a significant 1° AV block (PR of 400msec) – a complex that has actually been masquerading as a T-wave in the remaining EKG. Without this opportune advantage one might easily interpret the rhythm as junctional (absence of P-waves) with a prolonged QT interval.
It pays to carefully scrutinize every part of the 12-lead EKG and the rhythm strip. As in this case it can truly alter the interpretation.