What happens when a pacemaker fails to capture?

What happens when a pacemaker fails to capture?

Undersensing. Undersensing occurs when the pacemaker fails to detect spontaneous myocardial depolarization, which results in asynchronous pacing. Atrial or ventricular pacing spikes arise regardless of P waves or QRS complex. This typically results in the appearance of too many pacing spikes, as seen on ECG (Fig.

What is failure to capture on ECG?

Failure to capture occurs when a pacemaker pulse is given, but the impulse is unable to depolarize non-refractory myocardial tissue. Pacer spikes are seen on an ECG, but there is no cardiac response. Once again, the patient’s native rhythm is seen on the ECG.

How is failure to capture a pacemaker treated?

The typical treatment in this case is repositioning of the lead in the postoperative period. Patients who are dependent on pacing may require a temporary pacemaker or asynchronous pacing if there is just an acute increase in the threshold until lead repositioning.

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.

What are the most common problems with a pacemaker?


  • Infection near the site in the heart where the device is implanted.
  • Swelling, bruising or bleeding at the pacemaker site, especially if you take blood thinners.
  • Blood clots (thromboembolism) near the pacemaker site.
  • Damage to blood vessels or nerves near the pacemaker.
  • Collapsed lung (pneumothorax)

What causes failure to capture?

Failure to capture can result from several causes, including battery depletion, circuit failure, lead dislodgement or maturation, elevated capture thresholds due to progressive cardiac disease, metabolic abnormalities and or drugs.

How do you fix a malfunctioning pacemaker?

Apply transcutaneous pacing pads if external pacing is necessary. Intravenous fluids and inotropic support if symptomatic hypotension. Adjust the dose or withhold the medication. Pulse generator reprogramming based on underlying pacing malfunction.

How do I know if my pacemaker is working?

You can tell if your pacemaker is malfunctioning if you are starting to experience symptoms of arrhythmia. You might have chest pain, difficulty breathing, dizziness, or lightheadedness.

What activities can you not do with a pacemaker?

What precautions should I take with my pacemaker or ICD?

  • It is generally safe to go through airport or other security detectors.
  • Avoid magnetic resonance imaging (MRI) machines or other large magnetic fields.
  • Avoid diathermy.
  • Turn off large motors, such as cars or boats, when working on them.

What causes a pacemaker to fail to capture?

The most common cause of failure to capture is insufficient stimulus energy. Modern pacemakers have built-in functions to calibrate the stimulus amplitude and width according to myocardial excitability. This is done by repeatedly stimulating with gradually decreasing amounts of energy until the stimulus no longer yields an activation.

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 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.