Implantable cardiac defibrillator (ICD)An ICD is an
electronic device that constantly monitors the patient's
heart rhythm. When the device detects certain abnormal heart
rhythms, it delivers energy (a small shock) to the heart muscle to
restore a normal heart rhythm. The shock will be brief and may feel
uncomfortable, depending on how much energy the ICD delivers to
restore a normal heart rhythm.
Studies show that an implantable cardiac defibrillator (ICD) can
reduce this risk of death from sudden cardiac arrest. When a
life-threatening arrhythmia is detected by the ICD, a high-energy
shock is delivered to the heart muscle to restore a normal heart
rhythm. The shock that restores your heart rhythm will feel
uncomfortable, but it is very brief.
Cardiac resynchronization therapy (also called biventricular
pacing)
Cardiac resynchronization therapy (CRT) is
designed to treat the delay in heart ventricle contractions that
occur in some people with advanced heart failure. The CRT pacing
device is implanted and paces the lower chambers of the heart so
the right and left ventricle pump together. Small electrical
impulses are delivered from the device to the heart muscle through
leads (wires) to cause the right and left ventricles to pump
together.
Some patients with heart failure may benefit from CRT and an ICD
combination therapy. These devices combine biventricular pacing
with anti-tachycardia pacing and internal defibrillators to deliver
treatment as needed.
CRT improves symptoms of heart failure in about 50 percent of
patients who have been treated maximally with medications but still
have heart failure symptoms. CRT improves survival, quality of
life, heart function, the ability to exercise, and helps decrease
hospitalizations in select patients with severe or moderately
severe heart failure.
Internal monitoring devices
Some biventricular
pacemaker and ICD combination therapies have an internal monitoring
device inside so that your doctor or nurse can monitor not only
your heart rhythm, but also your heart function. You may be asked
to use a telephone to transmit data from your implanted cardiac
device to a computer server so that your doctor or nurse can
monitor your condition. Device companies have also developed a
pacemaker-like device that monitors the pressure in your lower
right heart chamber and a blood vessel near the heart. The data
stored in the device is sent electronically to a computer server so
that your doctor or nurse can review your heart function from a
remote location. These devices allow your healthcare team to
observe trends or changes in your heart function. Based on this
information, your healthcare team may make changes in your
medications or reinforce the lifestyle changes you need to make to
stay healthy.