Cardiologists at St George’s have implanted the world’s smallest pacemaker, known as the Micra Transcatheter Pacing System, in a first for the hospital.

Sixty years after implanting the UK’s first ever pacemaker in 1961, the cardiology team at St George’s has fitted a patient with a pacemaker that is 93% smaller than traditional devices.

The Micra pacemaker is a wireless device the size of a large vitamin capsule. Unlike standard pacemakers that are placed in the patient’s chest with wires running to the heart, the device is implanted directly into the heart where it delivers electrical impulses from an electrode.

To implant the pacemaker, a “straw-like” catheter is inserted into a vein in the upper thigh and used to move the device into the right ventricle of the heart. The catheter is then removed and the small incision is stitched closed.

“A person’s heartbeat is controlled by electrical pulses. The patient who received the device had AV block – often referred to as “heart block” – a condition where these electrical pulses are either slow or blocked entirely, meaning that the heart is at risk of stopping.” explained Dr Fadi Jouhra, Consultant Cardiologist who performed the procedure at St George’s last month with his colleague, Dr Manav Sohal.

“Until now, patients with AV block at St George’s could only be treated with traditional pacemakers which deliver electrical impulses to the heart via wires. The wireless technology used in the Micra device provides an important alternative when conventional pacemaker implantation is either not possible or best avoided.”

Dr Jouhra added: “This is an amazing piece of technology and the introduction of the device at St George’s is a big step forward in patient treatment.”