Echocardiographically guided left atrial ablation: characterization of a new technique.

Abstract

BACKGROUND:

Several techniques for percutaneous catheter-based radiofrequency ablation of left atrial myocardium have been described. Each is potentially limited by anatomic inaccuracy, radiation requirement, cardiac/extracardiac collateral damage, proarrhythmia, lesion impermanence, or unclear procedural endpoint.

OBJECTIVES:

The purpose of this study was to describe a new technique that may address some of these limitations.

METHODS:

In 200 consecutive patients with atrial fibrillation (AF), complete ablative encircling of right and left pulmonary venous vestibules was performed using radiofrequency energy applied via a standard ablation electrode. Lesions were guided by a collaborative nonfluoroscopic imaging strategy involving intra-left atrial echocardiography and CARTO. A discrete procedural endpoint was sought: complete electrical isolation of all myocardium subtended by the encircling lesions.

RESULTS:

After a procedure in which the total fluoroscopy time averaged 6 minutes, isolation was achieved on the left and right sides in 198 and 199 patients, respectively. In addition to the vestibule-encircling lesions, isolation required one or more additional focal lesions within the subtended myocardial territory in the majority of left vestibules and in a minority of right vestibules. Significant procedural morbidity was observed, including cerebroembolism resulting in death and mesenteric embolism resulting in hemicolectomy. Procedural success, defined at 2 years after the initial procedure and requiring no interim procedure, antiarrhythmic drug therapy, or apparent arrhythmia burden, was observed in a significantly greater proportion of patients with a paroxysmal (87%) than persistent AF (60%) syndrome. Only a small proportion of patients with recurrent AF had recurrence of conduction in previously isolated zones.

CONCLUSION:

This technique may have advantages over those previously reported, including improved anatomic accuracy, improved lesion safety and efficacy, and diminished radiation exposure.

• Authors: David Schwartzman, John Nosbisch, Debra Housel
• Journal: Heart rhythm (Heart Rhythm) Vol. 3 Issue 8 Pg. 930-8 (Aug 2006) ISSN: 1547-5271 [Print] United States
• PMID: 16876742 (Publication Type: Journal Article)

Topics

• Adult
• Aged
• Atrial Fibrillation (diagnostic imaging, physiopathology, surgery)
• Atrial Function
• Catheter Ablation (adverse effects, instrumentation, methods)
• Echocardiography
• Electrodes, Implanted
• Female
• Follow-Up Studies
• Heart Atria (diagnostic imaging, pathology, surgery)
• Humans
• Intraoperative Care
• Male
• Middle Aged
• Myocardium (pathology)
• Postoperative Care
• Pulmonary Veins (surgery)
• Recurrence
• Research Design
• Treatment Outcome