What is cardiac resynchronisation therapy?
In a healthy heart the walls of the main pumping chamber squeeze together at the same moment. In some people with a weak heart muscle the electrical signal is delayed, so one wall contracts later than the other and the heart pumps inefficiently, rather like rowers who are out of time. Cardiac resynchronisation therapy, sometimes called a biventricular pacemaker, is a small device placed under the skin below the collarbone with wires to both sides of the heart. It sends gentle, painless electrical signals that bring the walls back into time with one another in order to improve the heart's function.
Why is it done?
It is considered for patients with heart failure whose heart muscle remains weak on the best possible medication and whose electrocardiogram shows a delayed electrical signal. Resynchronising the heart can improve breathlessness and tiredness, allow you to do more, reduce admissions to hospital and improve survival. Some devices also include a defibrillator that can treat dangerous heart rhythms.
What happens on the day?
You will usually be admitted fasting on the day of the procedure. In the catheterisation laboratory the skin below your left collarbone is numbed with local anaesthetic and you are given sedation. Through a small cut, wires are guided along a vein into the heart under X-ray, one or two to the right side and one into a vein on the outer surface of the left side. The wires are tested, connected to the device and the device is tucked into a pocket under the skin before the cut is closed with stitches.
What to expect afterwards
You stay in hospital overnight and a chest X-ray and device check are done before you go home the next morning. You keep the wound dry for at about a week and avoid lifting your arm above shoulder height for at least two weeks. The device is checked in the rooms at regular intervals and the settings are fine-tuned; the battery typically lasts several years and is replaced with a simple procedure. Not everyone will benefit: on average, two out of every three recipients have a significant improvement in heart function.
Possible complications
Bruising or a collection of blood at the device pocket is the most common problem and usually settles on its own. Infection of the pocket occurs in a small number of patients and may require antibiotics or even removal of the device. Occasionally the lung is nicked while the vein is found, causing air to leak around the lung, which may need a chest drain. A wire can move out of position and need repositioning, or stimulate the diaphragm and cause hiccup-like twitching. Rarely the heart or a vein is injured, causing bleeding around the heart.
This information does not replace a consultation. Please discuss your own risks and options with your cardiologist.