Catheter ablation of permanent atrial fibrillation: medium term results

Abstract

Objective: To investigate the feasibility of catheter ablation as a treatment for symptomatic patients with longstanding permanent atrial fibrillation (AF). Methods: Radiofrequency ablation was applied to encircle all pulmonary veins (PVs) and create lines from the left inferior PV to the mitral valve, along the roof of the left atrium between the PVs, and along the tricuspid valve-inferior vena cava isthmus. A seven day Holter was recorded at discharge and at follow up to assess arrhythmia burden. If patients developed a symptomatic, sustained atrial arrhythmia a repeat ablation procedure was advised. Results: 42 patients underwent the procedure that took a mean of five hours with 50 minutes of fluoroscopy. After a median follow up of 8.4 months, 31 of 41 surviving patients (76%) were in sinus rhythm. Of these, 29 patients were no longer taking any antiarrhythmic drugs but 22 (52%) required more than one procedure. During follow up 49% experienced a sustained atrial tachycardia. Twenty six repeat procedures were performed. Maintenance of sinus rhythm after the first, second, or third procedure was 36% (15 of 42), 58% (11 of 19), and 71% (5 of 7), respectively. From a total of 68 procedures there were two serious complications (2.9%): a stroke from which a full recovery was made, and a PV stenosis. Conclusion: Catheter ablation can be used to cure longstanding permanent AF; however, there is a significant complication rate. Whether this is offset by a mortality benefit associated with sinus rhythm is unknown. Many patients will need more than one procedure to achieve success.

Recurrence of Atrial Tachyarrhythmia During the Second Month of the Blanking Period Is Associated With More Extensive Pulmonary Vein Reconnection at Repeat Electrophysiology Study

“…23 A 3-dimensional navigation system (CARTO 3; Biosense Webster, Diamond Bar, CA) was used in all cases to create an electroanatomical map of the left atrium, and where possible, this was integrated with a computed tomography or magnetic resonance imaging reconstruction of the left atrium (CartoMerge; Biosense Webster). 24 PVI was performed in a wide-area circumferential ablation pattern using a Thermocool SmartTouch irrigated contact force-sensing radiofrequency ablation catheter (Biosense Webster …”

Ablation to Treat Atrial Fibrillation: Beyond Rhythm Control

“…15,16 The duration of atrial fibrillation was 3 to 7 years, and the presence of structural heart disease was variable. 15,16 Because ablation to treat atrial fibrillation is a long procedure, generally 3 to 5 hours, 7,11,12 either moderate sedation or general anesthesia is used. The choice is determined by institutional practice and patient assessment.…”

“…7 Duration of fluoroscopy for this procedure has been documented at more than 60 minutes. 7,11 Current ablation techniques are focused on targeting susceptible atrial tissue, electrical triggers, or areas associated with autonomic tone. 15 These factors are key to the initiation and perpetuation of the rhythm.…”

“…Left-sided atrial mapping is then initiated by using the CARTO XP Navigation System (Biosense-Webster, Inc, Diamond Bar, California) or the Ensite Velocity system (St Jude Medical, St Paul, Minnesota) to create 3-dimensional reconstructions of the left atrium and pulmonary veins and label the pulmonary vein os, mitral annulus, septum, and appendage. 11 Once the left side of the heart has been reached, systemic heparinization is started to achieve an activated clotting time (ACT) of 300 seconds or greater. Blood samples for ACT determination are obtained every 15 minutes after administration of a 100 U/kg bolus of heparin and then every 30 minutes once the target ACT is achieved.…”

“…via a pump during creation of the lesions is used to prevent buildup of char, which may be associated with clot formation, at the proximal end of the ablation electrodes. 7,11 This flushing can result in administration of an additional 1 to 2 L of intravenous fluid during the procedure; therefore urine output , Inc), is used. The Lasso, which is placed at the ostium of each pulmonary vein, is used to examine the circumference of the pulmonary vein antra for potentials.…”