Treatments - Cardiac resynchronisation therapy

Pacemakers and ICDs are usually implanted for disturbances in heart rhythm. For the last few years it has been recognised that implanting an extra (usually third) wire that runs around the back of the heart, may be very effective in improving the pumping action of the heart in selected patients with heart failure. See the diagnosis section, heart failure. This extra wire allows the electrical and mechanical activity of the heart to be ‘resynchronised’, hence the name. Patients with heart failure are usually selected for this treatment on the basis of severe shortness of breath, allied to certain changes on the ECG or ultrasound scan (echocardiogram) that indicates they are likely to respond to cardiac resynchronisation. The term cardiac resynchronisation therapy (CRT) is often used.

This extra wire can be attached to a pacemaker – a resynchronisation, or CRT pacemaker, or an ICD – a resynchronisation, or CRT ICD. The latter is usually selected if the patient is believed to be at increased risk of abnormal dangerous fast heart beats. If you are being considered for CRT therapy, your doctor will discuss with you whether a CRT pacemaker or CRT ICD would be best for you.

From a practical viewpoint, the implantation procedure is a little more complicated than for an ordinary pacemaker or ICD, taking approximately 2 hours, sometimes longer. As the extra lead can displace a little more readily than the other wires, very careful follow up is recommended. As a final point, it is important to recognise that CRT is a complimentary treatment to the drugs used to treat heart failure, and not a replacement.