Cardiac contractility modulation device implantation for heart failure

2.1 Heart failure is a complex clinical syndrome of symptoms and signs that happen when the heart is not working well enough, leading to reduced blood flow to body tissues. It can lead to oedema in the lungs (causing breathlessness) and swelling of the legs. Other symptoms include reduced ability to exercise, fatigue and malaise. Heart failure can be caused by structural or functional abnormalities of the heart.

2.2 NICE's guideline describes the diagnosis and management of chronic heart failure in adults. Treatments for heart failure include drugs to improve heart function, cardiac rehabilitation, cardiac resynchronisation therapy and cardiac transplantation. Cardiac contractility modulation device implantation may be an option for people with advanced heart failure that hasn't responded to conventional therapy.

2.3 Cardiac contractility modulation device implantation for heart failure is usually done under local anaesthesia. A device similar to a pacemaker is implanted in the right or left pectoral region and is connected to 2 standard pacemaker leads that are threaded through veins into the right ventricle. The electrodes in the right ventricle are placed on the ventricular septum at least 2 cm apart. These sense ventricular activity and deliver cardiac contractility modulation signals. An optional additional lead may be used to sense atrial activity (usually placed in the right atrial appendage). In contrast to a pacemaker or a defibrillator, the system is designed to modulate the strength of contraction of the heart muscle rather than the rhythm. Pulses are delivered at regular intervals throughout the day.

2.4 The device is recharged using a home-based charger system, typically on a weekly basis. Charging sessions last about 40 to 60 minutes.

2.5 The aim is to improve the heart's contractility, therefore improving a person's ability to exercise and quality of life.