What is a cardiac device?

Device is an instrument connected to your heart to improve its function. Usually it recquires high power and need to be recharged frequently through drive lines coming out of the body.

  The devices are:

  • Implantable cardiac defibrillator (ICD)
  • Cardiac resynchronisation Therapy(bi-ventricular pacing)
  • Left ventricular assist devices

Implantable Cardiac Defibrillator (ICD)


This is a match box sized computer implanted under the skin usually in the chest wall and connected to the heart chambers through wires passing through one of the veins.

The computer can sense the rhythm of heart through the wires, give electrical stimulus to increase the rhythm if its is slow, or give a DC shck if the rhythm is  too fast and dangerous type. Hence this can prevent sudden death in many instances.

What is Sudden Cardiac Arrest (SCA)?

Patients with cardiac failure is ten times more prone than general population to drop dead suddenly either because heart stops suddenly or heart beat too fast and ineffectively without ejecting blood from the heart.

Relatives of patients with heart failure must be aware of this and should be taught to give cardio-pulmonary resuscitation in case it happens at home.

Implantation of  automatic  cardiac defibrillator protects against this condition.

Cardiac Resynchronization Therapy (Biventricular Pacing)

Sometimes in heart failure both ventricles maynot contract synergetically. This may lead to aggravation of symptoms. This can be diagnosed by ECG by variations in its QRS complex.

If both ventricles can be paced , can result in improvement of symtoms.

Ventricular Assist Devices (VAD)

This is a mechanical pump connected between left ventricle and aorta in case of failing ventricles to enhance ejection from the heart.