ECG RHYTHM LAB

Third-Degree AV Block · Narrow Escape

Complete AV dissociation with a narrow-complex escape rhythm.

Generated six-second Lead II example · 48 bpm target rate · not a patient recording.

Typical rate

Escape: 40–60 bpm

Regularity

Independent atrial and ventricular rhythms

P waves

Regular but unrelated to QRS

PR interval

No fixed relationship

QRS

Narrow escape complexes

What to look for

P waves march through at their own rate; narrow QRS complexes do not imply normal conduction.

Show this rhythm

Sources and limitations