What is T wave Oversensing?
T-wave oversensing is associated with a typical aspect of alternating high-frequency (R-wave) and low-frequency (T-wave) signals on the near-field electrogram. The device counts the T-wave as an additional ventricular event doubling the measured ventricular rate.
What does failure to pace mean?
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. Sensing of such signals normally inhibits the pacemaker. Oversensing may lead to underpacing.
What does 3 pacer spikes mean?
Example 3 – Runaway pacemaker In the middle, three pacing spikes are seen at 60 ppm in VOO mode: the first is ventricular refractory (failed capture).
What are the types of pacing modes?
- Single-chamber pacing. – VVI or VVIR pacing. – AAI or AAIR pacing.
- Dual-chamber pacing. – DDD or DDDR pacing. – DDI or DDIR pacing. – Less common modes. VDD pacing. DVI pacing.
- Asynchronous pacing. – AOO, VOO, or DOO mode.
How do you fix Oversensing T waves?
It is possible to overcome T wave oversensing by reprogramming the device . T wave oversensing has also been reported in long QT syndrome and in one case an epicardial pace/sense lead with stable R waves was needed to resolve the problem due to T wave oversensing .
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 pace?
Failure to pace/fire occurs when the pacemaker fails to deliver an electrical stimulus or the correct number of electrical stimuli per minute. Failure to pace is recognized by a lack of pacemaker spikes and a return to the rhythm that indicated the need for a pacemaker.
What is failure to capture in pacemaker?
Pacemaker “Failure to capture”. Failure to capture is when the pacemaker signal fires but there is no response. This is identified by having pacing spikes present with no resulting QRS, (capture).
What is failure to sense pacemaker?
Failure to sense or undersensing occurs when the pacemaker fails to recognize spontaneous myocardial depolarization.