Cardioverter-Defibrillator Implantation: Treatment for Hypertrophic Cardiomyopathy

What is an Implantable Cardioverter-Defibrillator (ICD)?

An ICD is a device that is implanted surgically in the chest to monitor and promptly treat any life-threatening heart rhythms that may occur due to HCM. There are two types of ICDs that may be recommended:

Transvenous ICDs are implanted like pacemakers in the upper chest with thin wires that connect to the heart. If a life-threatening heart rhythm is recognized, an attempt to pace the rhythm is made and, if needed, a shock is delivered to re-establish normal rhythm.

Subcutaneous ICDs are placed on the side of the chest and the wire tunneled along the sternum under the skin. It also continuously monitors the heart rhythm and will deliver shock therapy to restore a normal rhythm when needed.

The selection of the type of ICD will be made on an individual basis.

Who Is a Good Candidate for Cardioverter-Defibrillator Implantation?

Patients with hypertrophic cardiomyopathy and one or more of the following risk factors for sudden cardiac death (SCD) might benefit from an implanted cardioverter-defibrillator:

• Personal history of ventricular arrhythmias
• Family history of sudden cardiac death
• Unexplained fainting or passing out (syncope)
• Severe thickening of the cardiac muscle
• Decreased heart function
• Presence of left ventricle (LV) apical aneurysm
• Extensive scarring or fibrosis of the heart muscle

Preparing for an ICD Procedure

Your electrophysiologist will advise you how to prepare in the days leading up to the procedure. You may be told to stop taking certain medications, stop smoking and drinking alcohol, and make other lifestyle modifications for a brief time prior to the procedure. For your safety, it is important to follow your doctor’s recommendations exactly.

Certain tests may also be ordered to ensure you are healthy enough to undergo the procedure. These may include blood tests, heart MRI, chest X-ray and heart-specific exams such as echocardiogram or electrocardiogram.

The Procedure

The procedure to place an ICD usually takes 2-3 hours and is performed in either the cardiac electrophysiology lab or the operating room. It is typically done under moderate sedation.

Most patients will spend one night in the hospital after ICD placement and go home the following day. Discharge instructions are provided and a follow-up appointment in the Cardiac Device Clinic will be scheduled before the patient leaves the hospital. University Hospitals Cardiac Device Clinics are located throughout northeastern Ohio and are staffed by highly trained cardiac device nurses.

Patients are advised to refrain from driving for a period of time following the implant. The incision should be kept dry for one week. Patients will also be told to avoid strenuous exercise for a short time to permit healing.

Risks and Benefits of the ICD Procedure

Implantable cardioverter defibrillators are very effective at reducing the risk of sudden cardiac death in select patients with hypertrophic cardiomyopathy. However, as with any procedure there are some risks, including:

• Bleeding at the incision site
• Damage to the blood vessel where the catheter is inserted
• Infection
• Pneumothorax or pericardial effusion due to perforation

These risks are considered low and are specific to the type of ICD used and the presence of any other medical conditions. Shared-decision making between the physician and patient will include a review of the risks and benefits and will take into account the patient’s health goals, preferences and values. Our expert, multidisciplinary teams work together to provide patients with a safe, seamless experience from preparation and pre-op testing, to day-of-procedure navigation and support, through recovery, discharge and rehabilitation.