Catheter Ablation

Catheter ablation treats an arrhythmia at its source. Once an electrophysiology study has located the tissue driving the abnormal rhythm, energy delivered through the catheter tip creates a small, controlled scar there. Scar does not conduct electricity, so the faulty circuit is interrupted and the rhythm can no longer sustain itself.

Unlike medication, which suppresses an arrhythmia for as long as it is taken, ablation aims to eliminate it.

• Radiofrequency — heat delivered point by point, the long-established approach used for most arrhythmias
• Cryoablation — freezing, delivered through a balloon for atrial fibrillation or a catheter tip elsewhere; often preferred near the normal conduction system, where its effects can be tested before becoming permanent
• Pulsed field ablation — a newer approach using electrical fields that preferentially affect heart tissue, sparing nearby structures such as the esophagus and the phrenic nerve

SVT, AVNRT and accessory pathways are the most successfully ablated rhythms, with single-procedure success rates typically above 90 to 95 percent, and ablation is often offered as a first-line alternative to lifelong medication.

Typical atrial flutter is likewise ablated with a high success rate at a well-defined location.

Atrial fibrillation is more involved. The procedure centers on pulmonary vein isolation — encircling the veins where most AF triggers arise. Results are good but less absolute: many patients need more than one procedure, and success is higher for paroxysmal AF than for long-standing persistent AF. Ablation is generally offered when symptoms persist despite medication, or earlier in selected patients.

Ventricular tachycardia and frequent PVCs can also be ablated, with an approach that depends on whether the heart is otherwise structurally normal.

An ablation typically takes two to four hours and may be done under conscious sedation or general anesthesia depending on the rhythm being treated. Preparation mirrors an EP study: nothing to eat or drink after midnight, and specific instructions on holding antiarrhythmic and blood-thinning medications. For atrial fibrillation, imaging such as a TEE or a cardiac CT is often performed beforehand to exclude a clot and to map the anatomy.

Most patients stay overnight and go home the following day, then avoid heavy lifting and strenuous activity for about a week.

Palpitations, skipped beats and short runs of the old rhythm are common in the first weeks to three months while the ablation lines mature and inflammation settles. This blanking period is expected and does not mean the procedure failed. Chest discomfort that is worse lying flat can occur from irritation of the sac around the heart.

Blood thinners are usually continued for at least two to three months afterward, and for many patients with atrial fibrillation they continue indefinitely based on stroke risk rather than on rhythm — an important point that is often misunderstood.

Bleeding or vascular injury at the groin is the most frequent. Less common risks include fluid around the heart requiring drainage, damage to the normal conduction system requiring a pacemaker, stroke, and — specific to AF ablation — narrowing of a pulmonary vein or, rarely, injury to the esophagus. Your electrophysiologist will review the risks specific to your procedure and your anatomy.