A way that the heart attempts to maintain a normal rate or rhythm
- May originate from the atria, AV junction or the ventricles and is names the approximate origin.
Atrial escape beats
Originate from anywhere in the atria except the SA node and usually meet the same criteria as other atrial complexes.
Aberrantly conducted complex
Individual complexes that appear different than other complexes of the underlying rhythm because they do not follow the same electrical conduction pathway as the underlying rhythm
- May have negative QRS complex when underlying rhythm has a positive QRS complex.
- Complex may be wider, narrower, or shorter than the complexes of the underlying rhythm
Pulseless electrical activity
Used to describe any rhythm that shows the conduction of electrical impulses without contraction of the myocardium.
- patient does not have a pulse.
Caused by hypovolemia, hypoxia, cardiac tamponade, or tension pneumothorax
Battery-operated devices that initiate electrical impulses in the myocardium.
Used to maintain a patient's heart rate in an emergency situation.
- Can be transvenous or transcutaneous
Implanted under the patients skin and is necessary when the patient's heart is unable to maintain a normal heart rate or a normal cardiac output, even with the aid of medications.
Only can be used of the AV junction and the ventricular electrical conduction pathways are functioning,
-Lead wire is placed into the right atrium
Impulse causes depolarization of the ventricular muscle
-placed either in the right or the left ventricle
AV sequential pacemakers
Stimulates depolarization of both the atria and the ventricles
- one wire in the right atrium and the other in the right ventricle
Used to greatly improve cardiac output by causing both ventricles to contract at the same time.
- three lead wires
- one in the right atrium, right ventricle, and left ventricle
Cardiac cell's ability to depolarize in response to the electrical impulse generated by an artificial pacemaker.
The percentage of complexes generated by the artificial pacemaker
Implanted cardioverter defibrillator
Designed to recognize ventricular dysrhythmias such as VF and VT and programmed to defibrillate the heart rate.
Used to treat tachydysrhythmias such as VF,VF or sinus dysrhythmia