Aims: This study sought to describe originating from the spontaneous scarring of left atrial anterior wall (LAAW) left atrial macroreentry tachycardia (LAMRT) clinical and electrophysiological characteristics, mechanisms, the formation of substrates. Methods and Results: 9 of 123 patients (89% female, age 79.78±5.59 years) had LAMRT originating from the LAAW and no cardiac surgery or prior left atrial (LA) ablation. The mean tachycardia cycle length (TCL) was 241.67±38.00 milliseconds. Spontaneous scars areas and low voltage areas (LVAs) in the LAAW were found in all patients. Successful ablation of the critical isthmus caused terminated of the LAMRT and was not inducible in all patients. Arrhythmogenic substrates of LAMRT were the spontaneous scars of LAAW, which matched with the aorta or/and pulmonary artery contact area. The area under the curve (AUC) of age and combination of gender and age for predicting the LAMRT originating from the LAAW were 0.918 and 0.951, respectively, with a cutoff value of ≥73.5 years of age and gender (female) predicting LAMRT with 88.9% sensitivity and 89% specificity. Conclusion: Combination of gender and age provides a simple and useful criterion to distinguish LAMRT from cavo-tricuspid isthmus (CTI) -dependent atrial tachycardia in macroreentry atrial tachycardia (MRAT) in patients without a history of surgery or ablation. Aorta or/and pulmonary artery contacting LA may be related to spontaneous scars. Ablation the isthmus eliminated LAMRT in all patients.

Introduction: The CA of AF may cause ridge edema, which may affect the safety of LAAC.Patients undergoing LAAC (left atrial appendage closure) with and without catheter ablation (CA) of atrial fibrillation (AF) were compared. METHODS: AF patients (N = 98) who went through LAAC (combined CA+LAAC procedures group; N=51), alone (LAAC group; N = 47) received transesophageal echocardiography (TEE) pre-procedural, intra-procedural and six-weeks post-procedure. The depth and ostial diameter of LAA, device compression, residual leak, and ridge thickness were evaluated in the patients. A comparison of patients having undergone combined and single procedures was done post-implantation. Finally, images of LAA and primary clinical characteristics were compared. RESULTS: TEE at six-weeks after implantation identified 27 patients with a residual leak (19 in the combined procedures group and 8 in the alone group; p = 0.04). A significantly higher rate of new residual leak was observed in the combined procedures group (25.5% vs 8.5%; p = 0.03). In the combined procedures group, a statistically significant lower amount of device compression ratio was also noted at implant as compared with that of six-weeks follow-up (22.44 ± 3.90 vs 19.59 ± 5.39; p = 0.03). No difference at significance level was found between both groups in all-cause, or cardiovascular deaths, and TIA/stroke/system embolism. CONCLUSIONS: Combined procedures of CA and LAAC for AF are feasible and safe, however, during follow-up, it might cause enhanced residual leak and smaller device compression ratio.