This study investigated the left atrial appendage (LAA) by computed tomography (CT) and magnetic resonance imaging (MRI) to categorize different LAA morphologies and to correlate the morphology with the history of stroke/transient ischemic attack (TIA).

The incidence of silent cerebral lesions after PVI is different depending on technologies used: PVAC increases the risk of 1.48 times compared to irrigated RF and cryoballoon ablation.

Patients with paroxysmal and persistent AF had a higher prevalence and number of areas of SCI per patient than controls and worse cognitive performance than subjects in sinus rhythm.

Strict adherence to an anticoagulation protocol significantly reduces the prevalence of SCI after catheter ablation of AF with RF energy.

Background-Radiofrequency left atrial catheter ablation has become a routine procedure for treatment of atrial fibrillation. The aim of this study was to assess with preprocedural and postprocedural cerebral magnetic resonance imaging the thromboembolic risk, either silent or clinically manifest, in the context of atrial fibrillation ablation. The secondary end point was the identification of clinical or procedural parameters that correlate with cerebral embolism. Methods and Results-A total of 232 consecutive patients with paroxysmal or persistent atrial fibrillation who were candidates for radiofrequency left atrial catheter ablation were included in the study. Pulmonary vein isolation or pulmonary vein isolation plus linear lesions plus atrial defragmentation with the use of irrigated-tip ablation catheters was performed. All of the patients underwent preprocedural and postablation cerebral magnetic resonance imaging. A periprocedural symptomatic cerebrovascular accident occurred in 1 patient (0.4%). Postprocedural cerebral magnetic resonance imaging was positive for new embolic lesions in 33 patients (14%). No clinical parameters such as age, hypertension, diabetes mellitus, previous history of stroke, type of atrial fibrillation, and preablation antithrombotic treatment showed significant correlation with ischemic cerebral embolism. Procedural parameters such as activated clotting time value and, in particular, electric or pharmacological cardioversion to sinus rhythm correlated with an increased incidence of cerebral embolism. Cardioversion was also associated with an increased risk of 2.75 (95% confidence interval, 1.29 to 5.89; Pϭ0.009). Conclusions-Radiofrequency left atrial catheter ablation carries a low risk of symptomatic cerebral ischemia but is associated with a substantial risk of silent cerebral ischemia detected on magnetic resonance imaging. Independent risk factors for cerebral thromboembolism are the level of activated clotting time and, in particular, the electric or pharmacological cardioversion to sinus rhythm during the procedure. (Circulation. 2010;122:1667-1673.)

PVI performed with a new irrigated catheter did not reduce significantly the SCL risk when compared to a standard irrigated catheter. Intraprocedural ACT reduces the SCL risk of 0.4% for each point of ACT increase. For ACT > 320 seconds no SCL occurred. Finally, compared to a standard irrigated catheter, PVI performed with a new irrigation design catheter reduces significantly saline volume infusion.

This study highlights that "typical" PV branching pattern is not a common finding. That 25.6% of the patients present at least 1 accessory PV needs to be kept in careful consideration when planning and performing transcatheter AF ablation. In addition, not only LA volume, but also each PV ostia and LA appendage are significantly enlarged in patients with persistent compared to paroxysmal AF.

LAA morphology relates to the burden of SCI in AF patients. Future research should corroborate if accessible methods (eg, echocardiography) are able to describe LAA morphology, permitting its use within universal thromboembolic risk predictors in AF patients.