Pacemaker monitoring is an obligatory part of the follow-up of affected patients. Taking into account the progressive technical development, this is a complex undertaking. This and the high accompanying morbidity (concomitant diseases), in the sense of further cardiovascular diseases, require a thorough and careful care of the patients. Pacemaker monitoring is part of aftercare, which begins immediately after implantation with individual programming. In this context, a detailed educational discussion takes place and the patient receives his pacemaker identification card, which serves to document each control examination in detail. After about four weeks, the second control should take place, during which the setting of the parameters as well as the wound conditions of the implantation operation are checked. The final setting of the pacemaker takes place after three to six months. Further controls should be scheduled at intervals of six to twelve months. Depending on the individual needs of the patient, additional controls should be performed. Indications for nonscheduled controls are:
- Acute cardiac events – e.g., myocardial infarction (heart attack).
- Radiation therapy
- Surgical procedures using the electrocautery (e.g., hemostasis with electric current).
- Chronic infections/ sepsis (blood poisoning) – this may indicate that the pacemaker is colonized with germs
- Defibrillation (A defibrillator is a technical device that takes influence on the conduction of the heart and treats cardiac arrhythmias through the action of electricity) – defibrillation as a treatment measure of resuscitation in ventricular fibrillation, ventricular flutter and pulseless ventricular tachycardia.
- Malfunction of the pacemaker
- MRI examinations (magnetic resonance imaging: imaging procedure that does not use X-rays; the body or a part of the body is placed in a strong magnetic field; this examination is usually contraindicated for most types of pacemakers and can cause the device to malfunction, among other things)
- New onset of arrhythmias
- Syncope (momentary loss of consciousness)
Indications (areas of application)
- Follow-up care in the context of pacemaker care.
Contraindication (contraindications)
In principle, there are no absolute contraindications. However, individual components of the examination may be contraindicated and must be evaluated (investigated) by the treating therapist. The patient should be physically fit and cooperative for pacing.
The procedure
The tasks of this control examination are manifold: pacemaker control primarily serves to ensure the function of the same. Malfunctions or complications are detected and corrected. An important part of the control is the recording of the running time in the sense of the battery supply as well as the guarantee of the extension of the same. Furthermore, the pacemaker control detects whether a system replacement may be necessary and initiates related measures. In order to optimize the function of the pacemaker, corresponding parameters can be checked and readjusted. Overall, pacemaker monitoring serves to re-evaluate (reassess the findings) the pacemaker therapy and enables an individual adjustment of diagnostic and therapeutic options. Pacemaker control is always performed with the appropriate programming device of the manufacturer. Electronic pacemaker interrogation is used to record the following parameters:
- Battery status
- Electrode impedance (Electrical parameter related to impulse delivery by the pacemaker to cardiac tissue, giving indication of adequate pacemaker probe connection (junction)).
- Programmed parameters
- Diagnostic data
Furthermore, an ECG machine that is suitable for pacemaker control, a test magnet and emergency equipment for cardiopulmonary (cardiopulmonary-related) resuscitation including defibrillator, is required. For more complex issues, the following equipment should be available:
- Stress ECG – e.g., bicycle ergometer or treadmill.
- Long-term ECG – with pacemaker detection
- X-ray
An important component of pacemaker monitoring is a detailed history and thorough physical examination of the patient. The history should include the following aspects or symptom-oriented questions:
- Angina pectoris – “chest tightness”; sudden onset of pain in the cardiac region.
- Signs of pacemaker syndrome (term for an unnatural heart rhythm – caused by a pacemaker in VVI mode (chamber pacemaker) – that can lead to palpitations, dizziness, and impaired consciousness or even unconsciousness; this syndrome can be caused by partial misdirection of the stimuli emitted by the pacemaker)
- Load capacity
- Dyspnea (shortness of breath)
- Palpitations / palpitations
- Medication
- Syncope (loss of consciousness)
- Diaphragmatic twitching – symptom caused by co-stimulation of the phrenic nerve (nerve supplying the diaphragm) by the pacemaker.
The physical examination includes, in addition to the general physical status, the inspection of the so-called pacemaker pocket (pocket of tissue in which the pacemaker has been implanted), as well as the examination of blood pressure and the verification of any signs of heart failure (signs that could indicate heart failure.) such as peripheral edema (water retention) or pulmonary congestion (water in the lungs). This is followed by an ECG examination, as mentioned earlier. Other important examination parameters are as follows:
- Stimulation threshold – The stimulation threshold represents the lowest value that results in stimulation of the myocardium (heart muscle tissue) by the pacemaker.
- Perceptual threshold – The perceptual threshold refers to the sensitivity of the pacemaker to any type of incoming signal, such as interfering signals.Possible complications.
In the context of pacemaker control, complications concerning pacemaker therapy (see pacemaker) must be expected. Manipulation of a pacemaker can basically lead to arrhythmias with corresponding consequences.
