New Invisible Pacemaker Helps Treat Common Heart Rhythm Disorder

The Virtua Our Lady of Lourdes Hospital cardiac team is now caring for patients with the world’s smallest pacemaker that allows for pacing of the lower heart chambers in coordination with the top chambers in patients with electrical heart block.

The size of a large vitamin and placed inside the heart through a vein in the leg, the Medtronic MicraTM AV helps people with heart block—the slowing down or interruption of the electrical signal from the atria (the upper chambers of the heart) to the ventricles (the lower chambers) that causes the heart to beat. 

Heart block can develop as a result of heart damage or with aging, even without a particular injury. It is most often seen in people over 70 who have heart disease. Symptoms may include shortness of breath, palpitations, dizziness, or fainting. Some patients with heart block, also called atrioventricular (AV) block, receive a pacemaker to regulate their heartbeat.

“In people with heart block, the electrical signal is disrupted at the AV node, which is sometimes referred to as the heart’s electrical relay station. This can cause the heart to beat too slowly and not pump enough blood to the body,” said Virtua heart rhythm specialist Heath Saltzman, MD, FACC, FHRS, FACP. “The Micra AV senses the mechanical squeeze in the atrium and then paces the ventricle, so both chambers beat in synchrony.”

Most pacemakers are implanted under the skin in the upper chest and connected to the heart using thin wires called leads. The Micra is delivered to the heart through a catheter and attached to the inside of the right ventricle with four small anchors, making it invisible to the naked eye. Electrical impulses are transmitted through an electrode at one end of the device. 

The procedure to implant the Micra usually takes about 30 minutes or less. Patients receive minimal sedation and may go home the same day. The device is expected to last eight to 13 years before needing replacement.

The Virtua Our Lady of Lourdes Hospital Electrophysiology Laboratory is accredited by the American College of Cardiology, the first such center to achieve this designation in the state of New Jersey and greater Philadelphia region. To make an appointment with a Virtua heart specialist, call 888-847-8823.