Device therapy - specialists and information

What is device therapy?

The term "device therapy" refers to medical treatment with pacemakers, implantable defibrillators and other cardiac stimulators. Different systems can be used depending on the heart condition.

For example, there are wireless pacemakers for slow cardiac arrhythmias or defibrillators for tachycardia or ventricular fibrillation.

Patients suffering from advanced heart failure are usually given cardiac resynchronization therapy (CRT).

When is device therapy used?

Device therapy is used when medical or surgical therapy is no longer sufficient.

In device therapy, the heart receives technical support to enable it to continue working. In the simplest case, for example, a patient with angina pectoris receives a coronary stent to widen the constricted blood vessels.

Even more expertise is required if the heart's pumping function is restricted. Cardiac arrhythmias, for example, disrupt the normal function of the heart. This can result in fatigue, shortness of breath and dizziness, or even fainting (syncope).

If the heart beats very slowly or pauses for a long time between beats, the heart rate drops. Cardiac arrest is then possible. In such a case, implantable pacemakers can help, which can even control the heartbeat depending on the load via lower current pulses.

In addition, patients with cardiac insufficiency often require device therapy to support the diseased heart. Left ventricular assist devices are connected to the heart from the outside and control the heart function.

The benefits of implantable event recorders

In the case of cardiac arrhythmias, it can happen that these cannot be detected even in a 24-hour long-term ECG. However, the evaluation of the pattern of cardiac arrhythmias is essential for diagnosis and further treatment planning.

In such cases, it is possible to implant an event recorder or a loop recorder under the skin. This is done under local anesthesia. Doctors make a small incision and place the event recorder under the skin. It is not much bigger than a small USB stick.

The device records the patient's heartbeat over a period of up to three years. The doctor can read out the data from the event recorder and diagnose the cardiac arrhythmia. The patient has a small remote control with which he can set a marker at the touch of a button ifnoticeable cardiac arrhythmias occur.

Types, implantation and aftercare

Pacemakers are implantable devices that control the heart rhythm and thus give a slow heart a new impetus, for example. Pacemakers are also suitable for coordinating excitation conduction between the atrium and ventricle.

The device continuously measures the heartbeat via electrical impulses and supports it when necessary @ Lumos sp /AdobeStock

There are three basic types of pacemaker available today:

• Single-chamber pacemakers for the right ventricle
• Dual-chamber pacemakers for controlling the right atrium and right ventricle, and
• Three-chamber pacemakers for the coordination of the left and right ventricles as part of cardiac resynchronization therapy (CRT)

The cardiologist decides which pacemaker is suitable for which patient based on the available findings.

The implantation of a pacemaker does not require open heart surgery. The procedure takes barely more than 45 to 60 minutes.

The pacemaker consists of a metal housing containing computer chips and a long-lasting battery. Doctors insert the pacemaker box, which is about the size of a matchbox, under the skin via a small incision in the upper chest area. They then fix it in place.

Depending on the type of pacemaker, one, two or three electrodes ensure contact with the heart muscle. Doctors also push the electrode cables into the heart via a vein in the collarbone area. There they screw them to the heart muscle. Doctors close the skin pocket in which the pacemaker is located with a suture. From the outside, they program the computer chip through the wound dressing.

Patients can usually leave the clinic around one to two days after the pacemaker has been implanted. By then, the doctors have optimally adjusted the pacemaker.

Initially, check-ups are necessary every six to eight weeks to monitor the function of the pacemaker and readjust it if necessary. After that, check-ups take place every three to six months.

Pacemakers without electrodes: Who are they suitable for?

The electrodes of a pacemaker always pose a risk of infection and inflammation. Especially for younger patients with single-chamber pacemakers, doctors are increasingly considering an alternative: the pacemaker without electrodes.

The system works like a classic single-chamber pacemaker. What is different, however, is that doctors implant it directly into the right atrium. To minimize follow-up interventions, the battery life is up to 10 years. The implantation of these electrode-free systems is already possible today in specialized centers.

What is cardiac resynchronization therapy (CRT)?

Cardiac resynchronization therapy (CRT) is a special form of pacemaker. In patients with severe heart failure (cardiac insufficiency), CRT helps to synchronize contractions of the left and right ventricles.

As a result, the heart's pumping function returns to normal. The implantation procedure is similar to the pacemaker surgery described above. However, cardiac resynchronization therapy requires doctors to anchor three electrodes in the heart muscle.

Defibrillators: Implantation and functional difference to pacemakers

Implantable defibrillators can be divided into the groups already known from pacemakers:

• Single-chamber defibrillator
• dual-chamber defibrillator and
• CRT defibrillator (= cardiac resynchronization therapy)

Unlike a pacemaker, which gives slow hearts more impetus, the defibrillator helps fast heartbeats, such as ventricular flutter or ventricular fibrillation.

Because the heart beats so quickly, it can no longer develop the pumping power to maintain the blood flow. Without a defibrillator, cardiac arrest occurs.

Device therapy is implanted in the same way as a pacemaker. If the implanted defibrillator detects ventricular fibrillation, it generates a current impulse via the electrode anchored in the heart muscle. This allows the heart to return to its beating rhythm.

Although the amount of energy required for this is small, a defibrillator consumes more energy than a pacemaker due to the way it works. For this reason, implantable defibrillators are somewhat larger than pacemakers. In addition, all currently available implantable defibrillators also offer a pacemaker function.

The scars after a pacemaker operation are small and usually grow back well @ chris2766 /AdobeStock

Left ventricular assist device using a circulatory pump: implantation, aftercare and quality of life

Patients with severe heart disease may even require a heart transplant. However, it often takes time before a suitable transplant is available. Therefore, a technical solution is often necessary until then. Patients of advanced age are no longer eligible for a heart transplant. Device therapy using a circulatory pump helps here . The best-known circulatory pump is the left ventricular assist device (LVAD).

The LVAD is implanted under general anesthesia with the chest open. During the operation, the heart receives blood tubes and a heart pump, which later take over the transportation of blood and relieve the heart.

Following the 4 to 5-hour operation, patients remain in the intensive care unit for two to five days. Close follow-up care is provided in the clinic for the first three weeks.

The patient then goes to rehabilitation for four weeks. Long-term follow-up care begins on the first day after rehabilitation. A second check-up takes place 14 days later. At the end, the follow-up check usually only takes place every three months.

Where can I find device therapy specialists?

Device therapy of the heart belongs to the field of cardiology. Specialized clinics and centers for cardiology and cardiosurgery are therefore the best places to find device therapy specialists.

Here you will also find a selection of centers and specialists in cardiology/cardiac surgery who offer the various device therapies.