Cardiac Resynchronization Therapy (CRT/ CRT-D)

Cardiac Resynchronization Therapy (CRT/ CRT-D)

Cardiac Resynchronization Therapy (CRT), also known as a Biventricular Pacemaker, is an advanced heart failure treatment that helps the heart’s chambers beat in a more coordinated and efficient way. It is used for patients whose heart’s electrical system causes the left and right ventricles to contract out of sync, leading to poor pumping efficiency and worsening heart failure symptoms.

CRT can significantly improve heart function, reduce hospitalizations, and enhance quality of life in selected heart failure patients.

Who needs CRT Implantation ?

CRT is recommended for patients who have:

• Left bundle branch block (LBBB) or electrical conduction delay on ECG.
• Symptoms of heart failure (NYHA Class II–IV) despite optimal medical therapy.
• Dilated cardiomyopathy (ischemic or non-ischemic).
• Previous pacemaker or defibrillator but persistent heart failure symptoms.

How CRT Implantation done?

CRT implantation is usually done under local anesthesia and light sedation:

• 1. Small incisions are made below the collarbone.
• 2. Three pacing leads are inserted through veins — one in the right atrium, one in the right ventricle, and one on the left ventricle via the coronary sinus.
• 3. These leads are connected to the CRT device, which sends small electrical impulses to synchronize both ventricles.
• 4. The device is programmed and tested before closure.

Patients are typically discharged within 48-72 hours and can resume daily activities after recovery.

Benefits of CRT

• Improved heart pumping efficiency and cardiac output.
• Reduction in heart failure symptoms (breathlessness, fatigue, swelling).
• Decreased hospital admissions related to heart failure.
• Enhanced exercise capacity and quality of life.
• Reduced risk of sudden cardiac death when combined with defibrillator (CRT-D).
• Improved survival in eligible patients.

What are the Possible Complications after CRT Implantation?

Although generally safe, some potential risks include:

• Infection at the device site.
• Lead displacement or malfunction.
• Bleeding or hematoma formation.
• Pneumothorax (rare).
• Device or lead-related issues requiring reprogramming or replacement.

What is CRT-D and How It Differs from CRT?

CRT-D (Cardiac Resynchronization Therapy with Defibrillator) is an advanced heart device that combines two important functions — Cardiac Resynchronization Therapy (CRT) and an Implantable Cardioverter Defibrillator (ICD) — in a single unit.

Just like a CRT device, it helps both ventricles of the heart beat in a synchronized manner, improving heart function and relieving symptoms of heart failure. But in addition to that, the CRT-D can also detect and correct life-threatening arrhythmias (abnormal heart rhythms) by delivering an electric shock — just like a defibrillator — to prevent sudden cardiac death.