Now Insured, Patient Wants to “Get Checked Out”

ANSWER

There are three findings on this ECG: unusual P waves consistent with a possible ectopic atrial rhythm, a prolonged QT interval, and T-wave abnormalities in the lateral leads.

Note that the P waves are negative in leads I and II, as well as in all chest leads. This is highly suggestive of an ectopic atrial rhythm originating low in the atria, conducting retrograde into the atria, and overriding the sinoatrial node. Limb lead reversal would result in negative P waves in lead I, but not in other leads.

A prolonged QT interval is determined by consulting any of the standard charts that correlate maximum heart rates with QT intervals and gender. In men, the QT interval is considered “prolonged” when it exceeds 440 ms, unless the heart rate is extremely slow. 

Finally, T-wave inversions are present in the lateral leads (V₅, V₆). Although this may be an indication of lateral is­chemia, there is no clinical cor­relation in this patient.