The use of an esophageal catheter to check the results of left atrial posterior wall isolation in the treatment of atrial fibrillation

Advantages and challenges for noninvasive atrial fibrillation ablation

PURPOSE

Although catheter ablation is an effective therapy for atrial fibrillation (AF), risks remain and improved efficacy is desired. Stereotactic radiotherapy is a well-established therapy used to noninvasively treat malignancies with precision. We sought to evaluate stereotactic arrhythmia radioablation (STAR) as a therapeutic option for treating AF.

METHODS AND RESULTS

Three cancer patients with drug refractory AF were enrolled. Planning software using 3-D CT of the left atrium was used to design a desired ablation volume encompassing antral circumferential pulmonary vein isolation, roof and floor lines to create a "box" lesion set. After planning, patients were treated in the radioablation suite. STAR was able to deliver the intended radiation dose to the target in all 3 patients. No complications were observed over a follow-up period of 24 months. One patient with paroxysmal AF died from deterioration of cancer. The autopsy revealed evidence of fibroblasts and fibrogenesis in the region of atrial tissues targeted with radioablation. In one of these patients, left atrial posterior wall electrograms recorded from the esophagus before and 3 months after STAR indicated successful electrical isolation.

CONCLUSIONS

This is the first report of non-invasive radioablation of the left atrium with demonstration of successful electrical isolation. Although STAR may be safe and effective in delivering ablative energy to the left atrium, further evaluation is warranted regarding effectiveness.

Surgical treatment of atrial fibrillation: technique of thoracoscopic radiofrequency fragmentation of the left atrium

Presented in the article is a detailed description of a modified technique of minimally invasive surgical treatment of patients with atrial fibrillation - thoracoscopic radiofrequency fragmentation of the left atrium. This modification differs from the prototype GALAXY procedure by a significant increase of the 'quantitative' rather than 'qualitative' parameter of surgical aggression in relation to the left atrium. This technique results in creation of multiple transmural continuous closed lines of lesion to the left atrium and, consequently, a reduced risk of inadequate surgical treatment for atrial fibrillation. Besides the radiofrequency action on the wall of the left atrium, the protocol of the operation included destruction of the ligament of Marshall and resection of the left atrial appendage. An indication for performing this operation is the presence of various forms of atrial fibrillation.

Advanced Cardiac Signal Recording

Implantable loop recorders allow prolonged and continuous single-lead electrocardiogram recording, with the pivotal addition of remote monitoring. They have significantly shortened time to electrocardiographic diagnosis and appropriate therapy of many bradyarrhythmias/tachyarrhythmias and proved helpful in arrhythmia burden definition, offering invaluable information in the diagnostic workup for syncope and atrial fibrillation. Advanced cardiac signal recording is also possible by transesophageal catheters. They have been used to orient diagnosis during wide and narrow QRS complex tachycardias and also to perform minimally invasive pacing. Intracardiac electrophysiologic study remains, however, essential for diagnosis of several arrhythmias in the perspective of curative catheter ablation.