Article Content

Q: What's cardiac ablation and what are its indications?

 

A: Cardiac ablation destroys specific cells that are the cause or central conduction route of a tachydysrhythmia. Usual indications for ablation are atrioventricular (AV) nodal reentry tachycardia; a recurrent atrial dysrhythmia, especially atrial fibrillation; and ventricular tachycardia unresponsive to previous therapy or for which the therapy produced significant adverse reactions. Ablation is also indicated to eliminate accessory AV pathways or bypass tracts that exist in the hearts of patients with preexcitation syndromes such as Wolff-Parkinson-White syndrome (see WPW syndrome before and after ablation).

  
Figure. No caption a... - Click to enlarge in new windowFigure. No caption available.

Ablation is most often accomplished by using radiofrequency, which involves placing a special catheter at or near the origin of the dysrhythmia. High-frequency, low-energy sound waves are passed through the catheter, causing thermal injury and cellular changes that result in localized destruction and scarring. The tissue damage is more specific to the dysrhythmic tissue, with less trauma to the surrounding cardiac tissue than occurs with cryoablation or electrical ablation.

 

During the ablation procedure, defibrillation pads, an automatic BP cuff, and a pulse oximeter are used, and an indwelling urinary catheter is inserted. The patient is usually given moderate sedation. An electrophysiology study (an invasive procedure used to evaluate and treat various dysrhythmias that have caused cardiac arrest or significant symptoms) is performed, and attempts to induce the dysrhythmia are made. The ablation catheter is placed at or near the origin of the dysrhythmia, and the ablation procedure is performed.

 

Multiple ablations may be necessary. Successful ablation is achieved when the dysrhythmia can no longer be induced. The patient is monitored for another 30 to 60 minutes and then retested to ensure that the dysrhythmia doesn't recur.

 

Postprocedural care is similar to that for an electrophysiology study, except that the patient is monitored more closely, depending on the time needed for recovery from sedation.

 

Learn more about it

 

Cardiovascular Care Made Incredibly Visual!! Philadelphia, Pa., Lippincott Williams & Wilkins, 2007:106.

 

ECG Interpretation: An Incredibly Easy Pocket Guide. Philadelphia, Pa., Lippincott Williams & Wilkins, 2006:251.

 

Smeltzer SC, et al. Brunner and Suddarth's Textbook of Medical-Surgical Nursing, 11th edition. Philadelphia, Pa., Lippincott Williams & Wilkins, 2007:854-855.