80 year old female patient monitored during carotid endartarectomy procedure. Patient has a history of complete heart block.
Rhythm analysis indicates a junctional escape rhythm at 40 bpm with a third degree heart block. Premature ventricular contractions (PVCs) are present.
This encounter shows a complete block of electrical conduction between the atria and ventricles. This leads to a medical emergency known as third degree or complete heart block, where cardiac output is dangerously low. In this case, the atrial contractions are initiated from the junctional system. This can be determined through the low heart rate, as well as the narrow QRS.
Source: PhysioNet MGH001