- Pacemaker implantation
- MICRA™ pacemaker without probes
- Defibrillator implantation
- His bundle pacemaker
- Cardiac resynchronisation therapy
A pacemaker is an implantable device for the treatment of slow cardiac arrhythmias.
1st function
The pacemaker monitors heart activity and only emits impulses when required, i.e. when the heart rate becomes too slow. The electrodes transmit the electrical impulses to the heart muscle and, conversely, the heart activity to the electronics.
2 Who needs a pacemaker?
Patients with a slow heart rate and
-unconsciousness or dizziness
-shortness of breath or reduced exercise tolerance
3. pacemaker types
1-chamber pacemaker: 1 probe in the right ventricle
2-chamber pacemaker: 1 probe in the right atrium and 1 probe in the right ventricle
3-chamber pacemaker (CRT-P): 3 electrodes - 1 probe in the right atrium and 1 in each of the two main chambers (resynchronisation therapy)
Micra™ is the smallest pacemaker in the world, 93% smaller than conventional pacemakers and therefore about the size of a large vitamin capsule.
The Micra™ cardiocapsule does not restrict your movements. Unlike a conventional pacemaker, Micra™ is implanted into the heart through a vein in the groin and does not require electrodes to the heart. Micra™'s small size and minimally invasive implantation procedure leave no scarring in the chest area and no visible signs (bump under the skin) that a medical device is under the skin.
Source: Medtronic
Image copyright: Medtronic
A cardioverter defibrillator (ICD) is an implantable device for the treatment of rapid life-threatening cardiac arrhythmias by means of painless electrical impulses or electric shock delivery. An ICD always has an additional pacemaker function.
1st function
An ICD constantly monitors the heart rhythm and treats it if necessary.
ICD therapy
-terminates palpitations through electrical stimulation (overdrive)
-terminates ventricular fibrillation by electric shock
2 Who needs an ICD?
Primary prophylaxis:
- Patients without documented life-threatening cardiac arrhythmias but with a corresponding risk potential
Secondary prophylactic:
-Patients who have survived a life-threatening cardiac arrhythmia
-Patients in whom a rapid cardiac arrhythmia (ventricular tachycardia) has led to a drop in blood pressure or unconsciousness
A new type of pacemaker stimulates the natural heartbeat and can therefore effectively reduce the risk of heart failure.
Press release from Ulm University Hospital dated 26 July 2018 on Marieke Ehlen 'sHis-bundle pacemaker
Article in the SWP from 18/09/2018 Pacemaker reduces the risk of heart failure by Christine Liebhardt
Cardiac resynchronisation therapy (CRT) was developed for patients who, despite optimal drug treatment, suffer from symptoms of chronic heart failure, such as shortness of breath, poor performance and fatigue, caused by asynchronous, i.e. no longer simultaneous, pumping of the two heart chambers (ventricles).
By implanting a third probe in the left ventricle, in addition to the atrial probe and the one in the right ventricle, synchrony can be restored by simultaneous stimulation in both ventricles, thereby improving the reduced pumping performance.
This system can be used for both pacemaker and ICD patients.
Operation
After preparations such as the placement of an intravenous access, monitoring, blood pressure and pulse monitoring, the patient's chest area is disinfected and sterilely draped in the operating theatre. The procedure is performed under local anaesthetic without the possible risks of a general anaesthetic. A vein is accessed via an approx. 4 cm long incision in the upper chest area and the electrode(s) are inserted through this, advanced into the heart under X-ray fluoroscopy and attached. After testing the probes, a small "pocket" is prepared under the skin and the pacemaker / ICD is connected. The wound is then closed in layers.
Aftercare
Short outpatient check-ups to check the functionality of the pacemaker / ICD are carried out postoperatively after 1 month, after 3 months and then at ½-yearly intervals, which you can have carried out by your registered cardiologist or at our pacemaker outpatient clinic .
Approximately ten days after the implantation of a pacemaker, the skin at the surgical site under the collarbone will have healed to such an extent that the stitches can be removed. In order to avoid delayed wound healing or even the introduction of germs, it is recommended that the skin is only carefully cleaned around the wound with a flannel up to this point (the wound dressing should not get wet). As soon as the wound has healed and the stitches have been removed, you can wash or shower and bathe as normal.
In order to optimise the healing process and to avoid pulling on the pacemaker probes, the arm on which the pacemaker was implanted should not be raised above chest height for about two weeks after implantation.
* Source German Heart Foundation https://www.herzstiftung.de/Herzschrittmacher-Implantation.html
Pacemakers and sport
* Source German Heart Foundation https://www.herzstiftung.de/Herzschrittmacher-Sport.html
Pacemakers and holidays
* Source German Heart Foundation https://www.herzstiftung.de/Herzschrittmacher-Urlaub.html
In rare exceptional cases, electromagnetic fields emitted by some devices may cause temporary interference with the pacemaker. Signs of possible interference may include dizziness, palpitations or an irregular pulse. Once the wearer has switched off the device in question or moved away from the source of interference, a pacemaker will work normally again. When shopping, it is recommended that you walk quickly through anti-theft systems (e.g. behind the checkouts and at the entrance and exit) and do not stand still in the area. Electrical appliances should also be kept at least 15 to 20 cm away from a pacemaker, for example hairdryers, razors, soldering irons, mobile phones, two-way radios, drills, table saws, loudspeaker systems, heating pads, remote controls and magnets. However, with the exception of larger magnets (e.g. in magnetic mats against back pain or permanent magnet undulators), interference rarely occurs. With induction cookers, it is recommended to keep a minimum distance of 40 cm from the pacemaker.
* Source Biotronik Possible interference with the implant
Until now, the rule was that pacemaker wearers should generally avoid magnetic resonance imaging (MRI ), as these devices generate strong alternating magnetic fields. This can lead to overheating of the electrodes with an increase in the stimulation threshold, incorrect stimulation, possibly triggering dangerous arrhythmias and destruction of the device. MRI-capable pacemakers have been on the market since 2011.
* Source Medtronic MRI-capable pacemaker Advisa MRI and Ensura MRI SureScan and St. Jude Medical Conditionally MRI-safe pacemakers, profile
Examinations with X-rays, including computer tomography , can be carried out safely.
When using mobile phones , the Federal Office for Radiation Protection recommends a minimum distance of 20 cm from the implanted pacemaker. Cordless phones are considered harmless.
* Source Quarks&Co What distance do I have to keep between my mobile phone and a pacemaker?
Pacemaker patients must report in advance at the airport security checkpoint . A manual check is then carried out, as the devices can trigger an alarm in the metal detector. The manual metal detector must not be passed over the device in quick succession, as this can lead to temporary functional impairment.
* Source German Heart Foundation https://www.herzstiftung.de/Herzschrittmacher-Urlaub.html
If the pacemaker battery runs out after a few years, changing the pacemaker is a low-risk and less stressful operation. It only requires a short hospitalisation of 2 days.
After a small skin incision above the unit, the probes are detached from the pacemaker, a new device is inserted and connected to the probes. These remain in the same position in the heart for the rest of the patient's life.
In very rare cases, a defect may occur in the electrodes. This can be characterised by sudden dizziness. As the electrodes become ingrown in the heart after about six years, they are left in place and a new electrode is placed next to them. Only in the event of an infection on the probes do they have to be removed completely.
The sinus node in the heart is responsible for generating a heartbeat and its speed. It generates around 60 to 80 electrical signals per minute, which are transmitted to the heart muscle cells. Once the muscle cells have received the electrical signal, they contract and form a heartbeat.
In sick sinus syndrome, the sinus node is scarred. As a result, the function of many cells in the sinus node is lost. If the sinus node sends too few impulses, the heart rate slows down. This condition is known as sinus bradycardia. Symptoms such as dizziness, tiredness or even fainting can occur. Sick sinus syndrome sometimes alternates between a slow and a fast heartbeat.
Sometimes the transmission of electrical signals from the sinus node to the heart muscle cells is temporarily or permanently disrupted. This is referred to as a sinoatrial block (SA block). This can exacerbate the dizziness and fatigue. In the worst case, signals are no longer transmitted.
If the sinus node does not transmit any impulses at all, this is known as a sinus node arrest. Sinus node arrest and total SA block are life-threatening.
Source: www.netdoktor.de
Image copyright: Swiss Heart Foundation
The heart beats 60 to 80 times per minute in a phase without physical exertion. The electrical impulses for the heartbeats are generated in the so-called sinus node in the right atrium of the heart. They are transmitted from the sinus node via the so-called AV node to the muscle cells of the left and right ventricles. The muscle cells then contract.
Sometimes the electrical impulses are transmitted very slowly from the AV node to the ventricles. A so-called block is located behind the AV node. There are three different forms of AV block:
In a 1st degree AV block (AV block 1), the transmission of the electrical signal is not interrupted, but it is significantly delayed. In most cases, those affected have no symptoms. The block becomes visible by chance in the ECG (electrocardiogram).
An AV block of the 2nd degree (AV block 2) is characterised by the fact that not all electrical signals from the atrium reach the ventricles. A distinction is made between a Wenckebach AV block and a Mobitz AV block. Either electrical impulses are transmitted alternately or not, or the transmission becomes increasingly sluggish until it fails completely.
In a 3rd degree AV block (AV block 3), the conduction of the signal from the atrium to the ventricle is completely interrupted. However, the heart muscles are able to generate very slow beats themselves. The heart then continues to beat at a frequency of 20 to 30 beats per minute.
Source: www.netdoktor.de
Image copyright: Swiss Heart Foundation
Ventricular tachycardias are generally dangerous arrhythmias from the ventricle that harbour the risk of sudden cardiac death. If ventricular tachycardia is detected, secondary prophylactic implantation of a defibrillator (ICD) is often the treatment of choice in order to prevent death from the arrhythmia in the future. Regularly occurring, so-called monomorphic ventricular tachycardias, i.e. those that always originate from the same site, can also be treated by catheter ablation under certain circumstances. To do this, it must first be determined whether there is an underlying heart disease. Sometimes the arrhythmia can also be treated by treating the underlying disease. Catheter ablation requires so-called 3D mapping procedures to create a three-dimensional image of the right and/or left ventricle and to record the electrical activation during the arrhythmia. If the mechanism of the ventricular tachycardia can be clarified, the development of the tachycardia can be prevented by radiofrequency ablation. There are also rare cases of so-called idiopathic ventricular tachycardia, which occur without other heart disease and are usually relatively accessible to catheter ablation.