A leadless pacemaker is a very small heart rhythm device that’s implanted directly inside the heart—without the wires (“leads”) used in traditional pacemakers.

How it’s different

A standard pacemaker has:

• A pulse generator under the skin (usually near the collarbone) – the ‘pacemaker’ itself, connected to
• Wires that run into the heart

A leadless pacemaker combines everything into one tiny capsule (about the size of a large vitamin pill) that sits entirely inside the heart.

How it’s implanted

• Inserted through a vein in the groin (or neck) using a catheter
• Guided into the right ventricle of the heart
• Attached to the heart wall with small prongs or screws
• No chest incision and no visible lump under the skin

What it does

Like a regular pacemaker, it treats slow heart rhythms (bradycardia) by sending electrical impulses to keep the heart beating at a safe rate.

Common conditions it treats

• Bradycardia
• Some cases of Atrial fibrillation (when pacing support is needed)

Advantages

• No leads = fewer complications like wire breakage or infection
• Smaller and less visible
• Faster recovery after implantation

Limitations

• Usually only works in the bottom chamber of the heart (right ventricle) – though newer devices can either sense from the top chamber (right atrium) or have a second device implanted in the top chamber
• Not suitable for people who need more complex pacing
• Battery replacement means implanting a new device rather than swapping a generator

A leadless pacemaker is a newer, minimally invasive alternative to traditional pacemakers, currently primarily designed for select patients who mainly need more simple pacing support, or have had or are at high risk of complications from a conventional pacemaker.