Device Therapy - Specialists and Information

What is device therapy?

The term “device therapy” refers to medical treatment using pacemakers, implantable defibrillators, and other cardiac stimulators. Depending on the heart condition, different systems may be used.

For example, wireless pacemakers are used for slow heart rhythms, while defibrillators are used for tachycardia or ventricular fibrillation. 

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

When is device therapy used?

Device therapy is used when medication or surgery is no longer sufficient.

With device therapy, the heart receives technical support to help it continue functioning. In the simplest case, for example, a patient with angina pectoris receives a coronary stent to widen the narrowed blood vessels.

Even more expertise is required when the heart’s pumping function is impaired. Arrhythmias, for example, disrupt the heart’s normal function. This can lead to fatigue, shortness of breath, and dizziness, and in severe cases, even fainting (syncope).

If the heart beats very slowly or pauses for a prolonged period between beats, the heart rate drops. Cardiac arrest is then possible. In such cases, implantable pacemakers—among other treatments—can help by using low-voltage electrical impulses to regulate the heartbeat, even in response to physical exertion.

In addition, patients with heart failure (cardiac insufficiency) often require device therapy to support the diseased heart. Left ventricular assist devices are connected to the heart externally and regulate heart function.

The Benefits of Implantable Event Recorders

In some cases of cardiac arrhythmias, these may not be detectable even during a 24-hour long-term ECG. However, analyzing the pattern of the 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 larger than a small USB flash drive.

Over a period of up to three years, the device records the patient’s heartbeat. The doctor can retrieve the data from the event recorder and diagnose the arrhythmias. The patient has a small remote control that allows them to set a marker at the push of a button when they experience noticeable arrhythmias.

Types, Implantation, and Follow-Up Care

Pacemakers are implantable devices that control the heart’s rhythm and, for example, give a slow heart a new boost. Pacemakers are also suitable for coordinating the conduction of electrical impulses between the atria and ventricles.

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

Today, there are three basic types of pacemakers available:

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

The cardiologist determines which pacemaker is suitable for which patients based on the available findings.

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

The pacemaker consists of a metal casing containing computer chips and a long-lasting battery. Doctors insert the pacemaker—which is about the size of a matchbox—under the skin through a small incision in the upper chest area. They then secure it in place. 

Depending on the type of pacemaker, one, two, or three electrodes provide contact with the heart muscle. To do this, doctors insert the electrode leads through a vein near the collarbone and advance them into the heart. There, they secure them to the heart muscle with screws. Doctors close the skin pocket containing the pacemaker with a suture. They program the computer chip from the outside through the wound dressing.

Typically, patients can leave the hospital about one to two days after the pacemaker is implanted. By then, the doctors have optimized the pacemaker’s settings.

Initially, follow-up appointments are necessary every six to eight weeks to monitor the pacemaker’s function and make adjustments if necessary. After that, checkups are scheduled every three to six months.

Leadless Pacemakers: 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 leadless pacemaker. 

The system works like a traditional single-chamber pacemaker. The difference, however, is that doctors implant it directly into the right atrium. To minimize the need for follow-up procedures, the battery life is up to 10 years. These leadless systems can already be implanted today at specialized centers.

What is cardiac resynchronization therapy (CRT)?

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

This restores the heart’s pumping function to normal. The implantation procedure is similar to that of the pacemaker surgery described above. However, for cardiac resynchronization therapy, doctors must anchor three electrodes in the heart muscle.

Defibrillators: Implantation and Functional Differences from Pacemakers

Implantable defibrillators can be classified into the same groups as pacemakers:

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

Unlike a pacemaker, which stimulates a slow heartbeat, a defibrillator treats rapid heart rhythms such as ventricular flutter or ventricular fibrillation. 

Because the heart is beating so rapidly, it can no longer generate the pumping force needed to maintain blood flow. Without a defibrillator, cardiac arrest occurs.

The implantation of this device is similar to that of a pacemaker. If the implanted defibrillator detects ventricular fibrillation, it delivers an electrical shock via the electrode anchored in the heart muscle. This restores the heart’s normal 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 slightly larger than pacemakers. In addition, all currently available implantable defibrillators also offer a pacemaker function.

The scars left after pacemaker surgery are small and usually heal well @ chris2766 /AdobeStock

Left Ventricular Assist Device (LVAD): Implantation, Follow-Up Care, and Quality of Life

For patients with the most severe heart diseases, a heart transplant may ultimately be necessary. However, it often takes time for a suitable donor heart to become available. Therefore, a technical solution is often required in the meantime. Elderly patients are no longer eligible for heart transplantation. In such cases, device therapy using a circulatory pump can help. The best-known circulatory pump is the left ventricular assist device (LVAD).

The LVAD is implanted under general anesthesia via open-chest surgery. During the operation, blood tubes and a heart pump are attached to the heart; these will later take over blood circulation and relieve the strain on the heart.

Following the 4- to 5-hour surgery, patients remain in the intensive care unit for two to five days. Close follow-up care takes place at the hospital during the first three weeks.

Afterward, the patient undergoes four weeks of rehabilitation (reha for short). Long-term follow-up care begins on the first day after rehabilitation. A second follow-up appointment takes place 14 days later. After that, follow-up appointments are typically scheduled only every three months.

Where can you find device therapy specialists?

Cardiac device therapy falls within the field of cardiology. Specialized hospitals and centers for cardiology and cardiac surgery 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 that offer various device therapies.