Implantable Defibrillator

What is an Implantable Cardioverter Defibrillator (ICD)?

An Implantable Cardioverter Defibrillator (ICD) is a small electronic device designed to continuously monitor heart rhythm and automatically treat dangerous arrhythmias, especially:

Ventricular Tachycardia (VT)
Ventricular Fibrillation (VF)

These arrhythmias can impair the heart’s ability to pump blood and become life-threatening if not treated promptly.

The ICD can correct them using:

Anti-tachycardia pacing (ATP): rapid electrical impulses that painlessly interrupt the abnormal rhythm
Electrical shock (defibrillation): delivered only if necessary to restore a normal heartbeat

What is CRT-D?

The CRT-D (Cardiac Resynchronization Therapy – Defibrillator) is an advanced device that provides:

Defibrillation therapy (like a standard ICD) to treat life-threatening arrhythmias
Biventricular pacing (CRT) to restore coordinated contraction of the heart

CRT-D is indicated for patients with:

Heart failure
Reduced pumping function (low ejection fraction)
Dyssynchronous heart contraction (e.g., left bundle branch block)

Benefits include improved quality of life, reduced fatigue and shortness of breath, fewer hospitalizations, and often improved heart function.

How is ICD or CRT-D implantation performed?

The procedure is minimally invasive, performed in a hospital in a catheterization or electrophysiology laboratory.

1. Preparation

Local anesthesia is used (occasionally mild sedation)
The patient remains awake and comfortable

2. Venous access

A small incision is made below the collarbone
One or more leads (thin insulated wires) are inserted into a vein and guided to the heart under X-ray guidance:
- ICD: usually 1 lead (right ventricle)
- CRT-D: 2–3 leads (right atrium, right ventricle, and a vein on the left ventricle via the coronary sinus)

3. Device connection

The leads are connected to the pulse generator (the device itself), which is placed under the skin below the collarbone

4. System testing

The physician verifies correct sensing and stimulation
In selected cases, a short test shock may be delivered to confirm effectiveness

5. Closure

The incision is sutured or closed with absorbable stitches
No external components are visible, only a small bump under the skin

Procedure duration, recovery, and follow-up

Procedure time: 60–90 minutes (ICD); 90–150 minutes (CRT-D)

Hospital stay: 24 hours

Return to daily activities: 3–5 days, avoid lifting the arm on the implant side for 2–3 weeks

Driving: Usually after 2–4 weeks, depending on medical advice

Follow-upR: egular checks, often including remote monitoring

Is it painful?

No. The procedure is done under local anesthesia. Mild soreness or swelling at the implant site may occur for a few days.

Possible risks (rare)

Bruising or hematoma at the implant site
Infection
Lead displacement
Pleural or pericardial complications (very uncommon)
Need for device or lead repositioning (in selected cases)

ICD and CRT-D implantation are safe, effective, and potentially lifesaving treatments:

-Prevent sudden death from dangerous arrhythmias
-CRT-D can also improve heart failure symptoms and heart function
-No open heart surgery required
-Quick recovery and early return to daily activities