Blips and flips for quick identification of limb-lead reversal

Electrocardiographic (ECG) limb-lead reversals are common and can simulate myocardial infarction, ischemia, and axis deviation, yet they can be challenging to recognize.

All incoming first year cardiology fellows (n=6) at a single academic medical center were first assessed at baseline for their ability to identify limb-lead reversal patterns on 12-lead ECGs. The fellows were then taught a mnemonic "Blips and Flips" which was used to organize the six limb-lead reversal patterns into two visually intuitive categories. Blips represents low-amplitude patterns from bilateral arm-leg, RA-RL, and LA-RL reversals, while Flips represents inverted-lead patterns from LA-RA, RA-LL, and LA-LL reversals and the clockwise and counter-clockwise limb-cable rotations. Reminders using interactive and humorous repetition were administered two times per month for six months.

At baseline, 2 of the 6 fellows were able to identify the most obvious Flips sign of isolated inversion of Lead I indicating LA-RA reversal. None were able to detect the more nuanced Blips patterns or other Flips with Lead III inversion LA-LL reversal. After six months, all fellows could consistently identify all forms of Blips with remaining difficulty in lead III inversion (Flips) being occasionally called "ischemia" incorrectly.

This humor-integrated memorable mnemonic for a challenging concept helped to reduce trainee anxiety and improve long-term retention and accurate recall. This framework of limb-lead reversal can be extended to anyone who reads ECGs to improve diagnostic accuracy in ECG pattern recognition.