Conduction system pacing: setting the pace

When the heart has an abnormal rhythm, many patients are implanted with a small medical device called a pacemaker, which sends electrical signals that counteract the incorrect ones that are firing off in the heart, which cause the arrhythmia, and stimulate the muscles to make the heart beat at a normal rate. Innovations in the field mean that there are several types of pacemakers available on the market, such as conduction system pacemakers, which can be more effective in less disruptive ways for specific patients.

In this article, a consultant cardiologist explains what makes conduction system pacing therapy different from traditional pacemakers, and how patients can benefit from it.

What is a conduction system pacemaker?

Conduction system pacemakers (CSPs) work by directly targeting the heart’s conduction system, which manages the synchronisation (or, in the case of arrhythmic patients, the lack thereof) of the heart’s different chambers. Dysfunction of this system can occur through bradycardia (one or more chambers contract too slowly), tachycardia (which is the inverse of the former), heart failure, or blockage. Typical pacemakers are designed to stimulate the right ventricle, and are made up of the pulse generator (the battery and electronic components), and lead wires through which the electricity travels that are placed through a vein. The device is implanted under the skin, by the collarbone. Whilst mostly effective, pacemakers can err and end up contributing to the heart’s desynchronisation over time. 

By contrast, CSP can evade these issues through mimicking a more natural heartbeat pattern, contributing to improved function and longevity. It accomplishes this due to the device being placed directly into the conduction epicentre of the heart – rather than the exterior of the heart, such as the right ventricle – meaning that it doesn’t need to send out conflicting electrical signals but instead takes over the conduction right at the source. This leads to more efficient, more physiologically compatible, and more coordinated heart muscle contractions. It can be considered a form of cardiac resynchronisation therapy.

How is a conduction system pacemaker placed?

Much like other pacemakers, the device is implanted using a local anaesthetic procedure where a small incision is made below the collarbone, and the CSP lead is passed through a vein to the heart using imaging scans to correctly place it.

What are the benefits of using conduction system pacing?

There are several benefits of utilising a CSP over other methods, such as:

• Reduced or prevented fainting for patients experiencing syncope
• Patient independence, as they can safely return to work, driving, and other aspects of daily life
• Lowers the risk of heart failure or pacemaker-induced cardiomyopathy
• Longevity