The Cruise With No Snooze

ANSWER
The correct interpretation of this ECG includes sinus tachycardia with premature supraventricular complexes, some with aberrant conduction.

The first, third, fourth, and 17th beats on lead I at the bottom of the rhythm strip are consistent with premature atrial contractions (PACs), while the sixth, seventh, 12th, and 19th beats represent PACs with aberrancy. The change in the QRS complex in the latter is due to the delay through the conduction ­system.

This patient was treated with low-dose ß-blockers and instructed to discontinue use of his holistic medication. His symptoms resolved, and follow-up ECGs have shown no evidence of sinus tachycardia or PACs.