上岡 正志

AIMS: The relationship between local unipolar voltage (UV) in the pulmonary vein (PV)-ostia and left atrial wall thickness (LAWT) and the utility of these parameters as indices of outcome after atrial fibrillation (AF) ablation remain unclear. METHODS AND RESULTS: Two-hundred seventy-two AF patients who underwent AF ablation were enrolled. Unipolar voltage of PV-ostia was measured using a CARTO system, and LAWT was measured using computed tomography. The primary endpoint was atrial tachyarrhythmia (ATA) recurrence including AF. The ATA recurrence was documented in 74 patients (ATA-Rec group). The UV and LAWT of the bilateral superior PV roof to posterior and around the right-inferior PV in the ATA-Rec group were significantly greater than in patients without ATA recurrence (ATA-Free group) (P < 0.001). The UV had a strong positive correlation with LAWT (R2 = 0.446, P < 0.001). The UV 2.7 mV and the corresponding LAWT 1.6 mm were determined as the cut-off values for ATA recurrence (P < 0.001, respectively). Multisite LA high UV (HUV, ≥4 areas of >2.7 mV) or multisite LA wall thickening (≥5 areas of >1.6 mm), defined as LA hypertrophy (LAH), was related to higher ATA recurrence. Among 92 LAH patients, 66 had HUV (LAH-HUV) and the remaining 26 had low UV (LAH-LUV), characterized by history of non-paroxysmal AF and heart failure, reduced LV ejection fraction, or enlarged LA. In addition, LAH-LUV showed the worst ablation outcome, followed by LAH-HUV and No LAH (log-rank P < 0.001). CONCLUSION: Combining UV and LAWT enables us to stratify recurrence risk and suggest a tailored ablation strategy according to LA tissue properties.

Purpose: To elucidate the electrophysiological predictors of the intramural origins of left ventricular outflow tract-ventricular tachyarrhythmias (LVOT-VAs), and to clarify the involvement of anatomical factors. Methods: Twenty-nine successfully ablated LVOT-VAs patients with origins in the aortomitral continuity (AMC) (n = 8), aortic sinus of valsalva (ASV) (n = 9), great cardiac vein (GCV) (n = 5), and intramural myocardium (n = 7) were enrolled. Intramural origins were defined as when effective ablation from AMC and epicardium (ASV and/or GCV) was needed. The local activation time difference (LATD) was calculated as follows: (earliest AMC activation) − (earliest epicardial activation), and was presented as an absolute value. Electrophysiological parameters and anatomical factors predisposing the intramural origins were investigated. Results: LATD of intramural origins was significantly shorter than that of AMC and GCV (4.5 ± 2.6 vs. 12.1 ± 7.4 vs. 17.4 ± 4.7, P &lt 0.05), respectively. In multivariate logistic regression analysis, LATD was associated with intramural origins (odds ratio: 0.711, confidence interval: 0.514−0.985, P = 0.040). ROC analysis revealed LATD of 7 ms as cut-off value. In computed tomography analysis, some patients who had thick fat tissue below the GCV, and an unusual GCV running pattern might be misdiagnosed as intramural origins. Conclusion: LATD ≤ 7 ms was associated with intramural origins, but with some anatomical limitations.

Purpose: Atrial fibrillation (AF) often coexists with atrial septal defects (ASD). Each of the transcatheter closure for ASD and radiofrequency catheter ablation (RFCA) for AF have been established as the first-line therapy. However, there are limited data about therapeutic effect RFCA plus transcatheter ASD closure on AF recurrence in AF patients with ASD. The aim of the current study was to investigate the clinical impact of ASD closure following RFCA on AF recurrence. Methods: Forty-two ASD patients (17 males and 54 ± 20 years old) were enrolled and classified into three groups: ASD occlusion-sinus rhythm (ASO-SR) (n = 26), no AF history prior to ASD closure ASO-AF-RFCA (n = 11), RFCA was performed due to AF history before ASD closure and ASO-AF-anti-arrhythmic drug (ASO-AF-AAD) (n = 5), AF was treated with AAD before and after ASD closure. AF occurrence among the 3 groups was evaluated. Results: Kaplan-Meier analysis showed that ASO-SR and ASO-AF-RFCA groups showed a lower AF occurrence ratio than ASO-AF-AAD group during the 14- ± 9-month follow-up periods (P = 0.013). AF occurrence in ASO-SR and ASO-AF-RFCA groups was comparable (P = 0.480). Bi-atrial reverse remodeling, such as decrease in left atrial volume index (P = 0.049) and right atrial area (P = 0.046), and significant decrease in high-sensitivity C-reactive protein levels (P = 0.049) were identified in ASO-AF-RFCA group, but not in ASO-AF-AAD group. Conclusion: A combination of two percutaneous therapies was proven to be effective and induced bi-atrial reverse remodeling in association with inflammatory reaction.

BACKGROUND: To investigate the clinical implication of the temporal difference in atrial fibrillation (AF)-onset in acute decompensated heart failure (ADHF) and its impact on post-discharge prognosis. METHODS: 336 new-onset ADHF patients without any history of AF before admission were enrolled (201 males, 63 ± 16 year-old) and classified into two groups based on their history of AF: the Control group (No AF was detected during hospitalization, n = 278), and the In-hos-AF group (AF occurred during hospitalization, n = 58). Post discharge prognosis including rehospitalization due to worsening HF, cardiac death, all-cause death and cerebrovascular event were compared. RESULTS: Kaplan-Meier analysis demonstrated that the incidence of rehospitalization due to HF, cardiac death, all-cause death and cerebrovascular event in the In-hos-AF group was not significantly different from that in the Control group (P > 0.05 respectively). However, when AF recurred in the In-hos-AF group patients (n = 24, 41%) after discharge, the incidence of rehospitalization due to HF and cardiac deaths were higher than those without AF recurrence (P = 0.018 and P = 0.027 respectively). Cox proportional analysis revealed that AF developing after discharge was proven to be an independent risk factor for rehospitalization due to HF (HR 1.845, P = 0.043), cardiac death (HR 3.562, P = 0.013) and all-cause deaths (HR 2.138, P = 0.020). CONCLUSION: Clinical outcomes of new-onset in-hospital AF patients were as good as those without AF history until AF recurrence. However, AF recurrence led to worse prognosis. Therefore, treatment for new-onset in-hospital AF in ADHF patients might be postponed until AF recurrence.

BACKGROUND: The mechanism of esophageal thermal injury (ETI; esophageal mucosal injury and periesophageal nerve injury leading to gastric hypomotility) remains unknown when using a high-power short-duration (HP-SD) setting. This study sought to evaluate the characteristics of esophageal injuries in atrial fibrillation ablation using a HP-SD setting. METHODS: After exclusion of 5 patients with their esophagus at the right portion of left atrium and 21 patients with additional ablations such as box isolation and low voltage area ablation in left atrium posterior wall, 271 consecutive patients (62±10 years, 56 women) who underwent pulmonary vein isolation by radiofrequency catheter ablation were analyzed. In the 101 patients, a HP-SD setting at 45 to 50 W with an Ablation Index module was used (HP-SD group). In the remaining 170 patients before introduction of the HP-SD setting, a conventional power setting of 20 to 30 W with contact force monitoring was used (conventional group). We performed esophagogastroduodenoscopy after pulmonary vein isolation in all patients and investigated the incidence and characteristics of ETI. RESULTS: Although the incidence of ETI was significantly higher in the HP-SD group compared with the conventional group (37% versus 22%, P=0.011), the prevalence of esophageal lesions did not differ between the groups (7% versus 8%). Multivariate logistic regression analysis revealed that the use of the HP-SD setting (odds ratio, 6.09, P<0.001), and the parameters that suggest anatomic proximity surrounding the esophagus, were independent predictors of ETI. However, the majority of ETI in the HP-SD group was gastric hypomotility, and the thermal injury was limited to the shallow layer of the periesophageal wall using the HP-SD setting. CONCLUSIONS: Although the use of the HP-SD setting was a strong predictor of ETI, it could avoid deeper thermal injuries that reach the esophageal mucosal layer.