6: Pacemakers Flashcards
A single pacemaker spike is followed by a P wave, a normal PR interval, and a normal QRS complex.
Atrial or Coronary Sinus Pacing
QRS Complexes occur earlier than expected based upon the lower rate limit of the pacemaker.
Pacemaker Malfunction (Nonsensing)
The pacemaker will fire and stimulate the atria or ventricles at its own predetermined rate, independently of the intrinsic rhythm. The interval between the native and paced complexes is variable, while the intervals of the pacing spikes is constant.
Pacemaker Malfunction (Nonsensing)
Pacemaker spikes not followed by either a P Wave or QRS Complex.
Pacemaker Malfunction (Noncapture)
There is a normal or intrinsic P wave which, after a preset PR interval, is followed by a pacemaker spike and a paced QRS complex that has a bizarre morphology resembling a left bundle branch block or a ventricular complex.
Dual Chamber Atrial Sensing Pacemaker
Two pacemaker spikes are seen within each complex; there is an atrial spike and an associated P wave, followed by a ventricular spike and an associated paced QRS complex. The P wave morphology is variable, depending upon the location of the wire within the right atrium. The QRS complex is wide and bizarre; it usually has a left bundle branch block morphology.
Dual Chamber Atrioventricular Sequential Pacing
Every QRS complex is preceded by a pacemaker stimulus. The QRS complex is abnormal, wide, and bizarre, resembling a ventricular beat. The QRS complexes usually have a left bundle branch block configuration since the ventricular lead is most commonly located in the right ventricle.
Ventricular Pacing with 100% Capture
A single pacemaker spike is followed by a QRS complex which is wide and bizarre and resembles a ventricular beat. There are some normal intervening QRS complexes that suppress the pacemaker when they occur faster than the rate set for the pacemaker.
Ventricular Demand Pacemaker
