A pacemaker is a small device that’s placed under the skin of your chest or abdomen to help control abnormal heart rhythms. This device uses electrical pulses to prompt the heart to beat at a normal rate. Pacemakers are used to treat heart rhythms that are too slow, fast, or irregular. These abnormal heart rhythms are called arrhythmias. Pacemakers can relieve some symptoms related to arrhythmias, such as fatigue (tiredness) and fainting. A pacemaker can help a person who has an abnormal heart rhythm resume a more active lifestyle.
A pacemaker consists of a battery, a computerized generator, and wires. The generator sends the electrical pulses that correct or set your heart rhythm, and the wires carry pulses to and from various chambers of your heart and the generator.
An implantable cardiovertor defibrillator system or implantable cardiac devices (ICD), is a small electronic device that monitors heart rhythm and delivers a shock to correct a potentially fatal heart rhythm if it should occur. The generator is surgically implanted beneath the skin and muscle beneath the collarbone. Wire electrodes attach the pulse generator to the heart. Some of the wires are inserted through veins into the inside of the heart and can sense the heartbeat. Other wires may be attached directly to the heart. These wires are used to deliver the shock, if necessary, which converts the heart back to its normal rhythm.
Ablation targets a portion of the heart muscle and actually destroys a small section of the muscle tissue. These areas are carefully chosen by your doctor. During a catherization procedure, your doctor delivers small amounts of energy to these areas. This makes a helpful scar on the heart muscle. In some cases, when ablation is done in certain parts of the heart, you may still need a pacemake afterwards.
Your heartbeat is controlled by a smooth, constant flow of electricity through the heart. A short-circuit anywhere along this electrical pathway can disrupt the normal flow of signals, causing an arrhythmia (an irregular heartbeat). Cardiac ablation is a procedure used either to destroy these short-circuits and restore normal rhythm, or to block damaged electrical pathways from sending faulty signals to the rest of the heart.
Cardiac ablation is performed by a cardiac electrophysiologist — a physician who specializes in diagnosing and treating heart rhythm disorders. The procedure involves inserting catheters — narrow, flexible tubes — into a blood vessel, often through a site in your groin or neck, and threading them through the vein until they reach your heart. You will be given sedatives to make you relaxed and comfortable, and a topical anesthetic to numb your skin before the catheters are inserted.
Using electrodes on the tip of the catheters, the doctor first conducts an EP Study to pinpoint the location of the short-circuit. Once the precise location is confirmed, the “short-circuit” is either destroyed (to reopen the electrical pathway) or blocked (to prevent it from sending faulty signals to the rest of the heart). This is done by sending energy through the catheters to destroy a small amount of tissue at the site. The energy may be either hot (radiofrequency energy), which cauterizes the tissue, or extremely cold, which freezes or “cryoablates” it.