Ventricular Tachycardia Mnemonic: VT ACED

Memorize these six criteria, then apply them to the strips below.

• Very wide QRS (>160ms) strongly favors
• Total concordance (V1-V6 all deflect the same direction) strongly favors
• AV dissociation (P waves marching independently of QRS) pathognomonic
• Capture and fusion beats (narrow or hybrid beats during the run) pathognomonic
• Extreme axis (northwest axis, between -90° and +180°) strongly favors
• Doesn't fit typical BBB (bizarre morphology, no classic rsR' or rS) strongly favors

View full EKG criteria reference

ELI5: Ventricular Tachycardia

Your heart has its own electrical wiring. A normal heartbeat starts at the top (the SA node), travels through a relay station (the AV node), then zips down a highway of fast wires (the His-Purkinje system) that activate both pumping chambers at the same time. The whole trip takes less than a tenth of a second, and the EKG shows a narrow, clean spike.

Ventricular tachycardia skips the highway. The electrical signal starts in the pumping chamber itself, usually in damaged muscle from a prior heart attack. Instead of using the fast wires, it crawls through muscle tissue cell by cell. Slow travel means a wide, ugly spike on the EKG. And because the signal is stuck in a loop (circling around the scar like a car on a roundabout), it fires over and over, driving the heart rate to 150, 200, sometimes 250 beats per minute.

At those speeds, the heart can't fill properly between beats. Blood pressure drops. The brain loses its supply. The patient passes out. If the rhythm isn't stopped, it can degrade into ventricular fibrillation, where the heart quivers instead of pumping, and the patient dies within minutes.

The treatment depends on how sick the patient looks. If they're unconscious or crashing: an electrical shock resets the heart immediately. If they're awake and stable: IV medications (procainamide or amiodarone) can slow or stop the circuit. Long-term, patients get an implantable defibrillator, a small device under the skin that monitors the heart 24/7 and shocks it back to normal if VT returns.

The challenge on the EKG: not every wide, fast rhythm is VT. Some are harmless rhythms that just look like VT because of a pre-existing wiring detour (a bundle branch block). This drill teaches you to tell the difference.

Acknowledgements

EKG images sourced from MIMIC-IV-ECG (PhysioNet, ODC-By 1.0), Wikimedia Commons, ECGpedia (CC BY-SA 3.0), LITFL, ECG Wave-Maven (Harvard/BIDMC), ECG Learning Center (Utah), theSimTech, and open-access publications via PubMed Central.

For educational use only. Not a substitute for clinical judgment.