Junctional rhythm

Junctional rhythm

Junctional rhythm is an abnormal heart rhythm, where the AV node initiates electrical activity in the heart [ eMedicine: "Junctional Rhythms" http://www.emedicine.com/MED/topic1212.htm ] . This pathway does allow the atria to contract before the ventricles, however, this occurs via retrograde conduction [ medical dictionary http://medical-dictionary.thefreedictionary.com/retrograde+conduction] . An EKG exhibiting Junctional rhythm commonly presents with an inverted "P" wave (see EKG) due AV nodal origin of electrical signal [ Abnormalities in the ECG measurement http://library.med.utah.edu/kw/ecg/ecg_outline/Lesson4/index.html#PRinterval ]

In contrast, in normal conditions, sinus rhythm initiates in the Sinus node and activates the atria then progresses into the HIS bundle, down to the Purkinje fibers and up the ventricle. This results in the atria contracting before the ventricles.


References


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