Cardiac Devices
What Are Cardiac Devices?
Cardiac devices are specialized electronic implants or external tools designed to help monitor, support, or correct the function of the heart. These devices play a crucial role in managing arrhythmias, heart failure, and preventing sudden cardiac death. They may be temporary (external) or permanent (implanted).
What Is a Pacemaker?
A pacemaker is a small medical device implanted under the skin of the chest to help manage slow or irregular heartbeats (bradycardia). It sends electrical impulses to stimulate the heart when it beats too slowly or pauses.
Why do I need this device?
You may need a pacemaker if you have:
Persistent or symptomatic slow heart rate
Heart block (signal delay between upper and lower chambers)
Fainting spells caused by bradycardia
Fatigue or shortness of breath from irregular rhythm
Some types of atrial fibrillation
How is it implanted?
A small incision is made under the collarbone
Leads (wires) are threaded through a vein into the heart
The generator (battery and circuitry) is placed under the skin
The procedure takes about 1–2 hours, usually under local anesthesia
After the procedure, the pacemaker automatically adjusts to your heart’s needs.
What Is CRT?
CRT is a specialized pacemaker used for heart failure. It coordinates the contractions of the left and right ventricles, improving the heart’s ability to pump efficiently.
Why do I need this device?
CRT is beneficial if you have:
Moderate to severe heart failure (reduced ejection fraction)
Bundle branch block or delay in ventricular activation
Symptoms despite optimal medical treatment
A heart that is beating out of sync (dyssynchrony)
CRT improves heart function, reduces hospitalizations, and enhances quality of life.
How is it implanted?
Similar to a pacemaker, but three leads are placed (right atrium, right ventricle, and left ventricle)
The leads synchronize the contraction of both ventricles
It may be combined with an ICD (CRT-D) in high-risk patients
What Is an ICD?
An ICD is a device designed to prevent sudden cardiac arrest by detecting life-threatening arrhythmias like ventricular tachycardia or ventricular fibrillation and delivering an electrical shock to restore normal rhythm.
Why do I need this device?
You may need an ICD if you have:
Survived a sudden cardiac arrest
Diagnosed with dangerous arrhythmias
A weak heart (low ejection fraction) after a heart attack or in heart failure
Genetic risk factors (e.g., Long QT syndrome, Brugada syndrome)
ICDs are life-saving devices that act like an internal emergency team, ready to correct fatal rhythms.
How is it implanted?
Similar to pacemaker implantation
The ICD continuously monitors heart rhythm
If needed, it delivers painless pacing or a stronger shock to reset the heart
Modern ICDs are small and discreet