Are pacemaker spikes normal?
Pacing spikes are seen despite normal electrical activity. This is failure to sense (FTS or under-sensing).
What causes a pacemaker spike?
Causes include increased stimulation threshold at electrode site (exit block), poor lead contact, new bundle branch block or programming problems. ECG findings may be minimal, although presence of pacing spikes within QRS complexes is suggestive of undersensing.
What is a pacemaker spike?
It shows pacemaker spikes: vertical signals that represent the electrical activity of the pacemaker. Usually these spikes are more visible in unipolar than in bipolar pacing. In the first example, the atria are being paced, but not the ventricles, resulting in an atrial paced rhythm.
Can pacemaker cause T wave inversion?
Cardiac memory refers to T-wave inversions that result when normal ventricular activation resumes following a period of abnormal ventricular activation. We present a case of a 29-year-old man with a pacemaker who presented with new, deep symmetric T-wave inversions caused by cardiac memory.
What is the difference between failure to failure and pace?
Failure to capture (FTC), which means that the pacemaker stimulations do not result in myocardial activation. Failure to pace (FTP), which means that the pacemaker does not stimulate as expected. Oversensing, which means that the pacemaker senses signals that are not true P-waves or R-waves.
Where should pacing spike appear?
Pacing spikes can be found in front of the P wave if they come from an atrial pacer or in front of the QRS complexes if they are ventricular. There are even biventricular pacers that can generate very strange QRS complex morphology. However, the common factor between all pacemaker driven rhythms is they generate a small,…
What is failure to capture pacemaker?
Failure to capture is the inability of the pacemaker stimulus to depolarize the myocardium. The pacemaker fires but does not stimulate the ventricle/atria enough to cause contraction (i.e. energy delivered is not enough to cause depolarization).
What causes pacemaker oversensing?
Causes of oversensing include the following: Pacemaker crosstalk: Pacemaker generated electrical event in 1 chamber is sensed by the lead in another chamber, which results in inappropriate inhibition of pacing artifact in the second chamber. Crosstalk is only seen in dual chamber or biventricular pacemakers .
What is failure to sense pacemaker?
Failure to sense or undersensing occurs when the pacemaker fails to recognize spontaneous myocardial depolarization.