Posterior wall thickness of the confluent inferior pulmonary veins measured by left atrial intracardiac echocardiography: implications for catheter ablation.

BACKGROUND: Confluent inferior pulmonary veins (CIPV) is a rare anatomical variant. There is few evidence in the literature regarding anatomic landmarks consideration to guide radiofrequency application in avoiding complications in the esophagus in CIPV cases. METHODS: Of 986 consecutive patients undergoing atrial fibrillation (AF) ablation from July 2020 to June 2022, seven (0.7%) had CIPV with a common trunk connecting to the LA diagnosed by 3-dimensional contrast-enhanced computed tomography. Using intracardiac echocardiography (ICE) performed from the left atrium (LA), we measured the posterior wall thickness (PWT) of the CIPV adjacent to the esophagus and compared the measurement with the LA posterior wall thickness (LAPWT) at the left inferior PV level of 25 controls without CIPV. For ablation in CIPV patients, each superior PV was individually isolated, and box isolation of CIPV without ablating the CIPV posterior wall was added (tri-circle ablation technique). RESULTS: The CIPV PWT was 0.7 ± 0.1 mm, while non-CIPV LAPWT was 2.0 ± 0.4 mm (P < 0.001). In the CIPV group, upper and lower portions of the CIPV were both apart from the esophagus (mean distances, 6.7 ± 3.4 mm and 7.9 ± 2.7 mm, respectively). Individual superior PV isolation and box CIPV isolation resulted in complete isolation of all PVs, with no complications. All CIPV patients except one remained AF recurrence-free for 376 ± 52 days. CONCLUSIONS: Although CIPV frequency is low, CIPV PWT is very thin and special care is needed during ablation. A "tri-circle" ablation strategy avoids ablating in the thinnest portion of the posterior wall. Further studies are warranted to assess the safety.

Predictors of pulmonary vein non-reconnection in the second procedure after ablation index-guided pulmonary vein isolation for atrial fibrillation and its impact on the outcome.

INTRODUCTION: Although first-pass isolation (FPI) of the pulmonary vein (PV) has been suggested as a marker for PV isolation (PVI) durability, it has not been confirmed. Non-PV atrial fibrillation (AF) triggers were the main target in patients without PV reconnection in the second ablation procedure, but the outcome was unclear. We aimed to validate FPI as a marker of PVI durability and evaluate the outcome after the second procedure in patients without PV reconnection by comparing it to those with reconnection. METHODS: Among the 2087 patients undergoing the first ablation index-guided radiofrequency AF ablation, 309 with atrial tachyarrhythmias (ATs) recurrence and undergoing the second procedure were studied. Clinical characteristics and outcomes were compared between the patients without PV reconnection (PV non-reconnection group, n = 142) and with reconnection (PV reconnection group, n = 167). RESULTS: FPI in both PV sides in the first ablation procedure was significantly more frequent in the PV non-reconnection group (77.5%) than in the PV reconnection group (45.5%) (p < .001). Multivariate logistic regression analysis revealed that FPI (odds ratio, 3.71 [95% confidence interval, 2.23-6.19], p < .001) was the only predictor of PV non-reconnection. Radiofrequency applications for non-PV AF triggers were more frequently performed in the PV non-reconnection group (40.8% vs. 24.6%, respectively, p < .001). Kaplan-Meier analysis revealed that AT recurrence-free rate was significantly lower in the PV non-reconnection group (1-year recurrence-free rate, 62.7% vs. 75.4%, respectively; p = .01 by log-rank test). CONCLUSION: FPI was the only independent predictor of PV non-reconnection. Despite aggressive ablation for non-PV triggers, AT recurrence was more frequent in patients with PV non-reconnection.

Cardio-Ankle Vascular Index and Left Atrial Reverse Remodeling After Ablation for Atrial Fibrillation.

Arterial stiffness has been reported to cause left atrial (LA) remodeling due to increased left ventricular filling pressure, resulting in atrial fibrillation (AF). This study aimed to evaluate the association between LA reverse remodeling (LARR) after AF ablation and cardio-ankle vascular index (CAVI), an indicator of arterial stiffness.This study included 333 patients with AF (171 with paroxysmal AF and 162 with nonparoxysmal AF) and LA enlargement (LA volume index ≥ 34 mL/m2) who underwent AF ablation between December 2008 and July 2021. CAVI was evaluated preoperatively during AF (n = 155, 46.5%) or sinus rhythm (n = 178, 53.5%). Participants were divided into groups with LARR (n = 133, 39.9%) and without LARR (n = 200, 60.1%) according to whether the degree of decrease in LA volume index on transthoracic echocardiography 6 months after ablation was ≥ 15% or < 15%, respectively.Sinus rhythm was maintained in 168 (50.5%) patients within 3-6 months after the index procedure. Univariate analysis revealed that preoperative CAVI (7.80 ± 1.22 versus 8.57 ± 1.09, P < 0.001) was significantly lower, and the maintenance of sinus rhythm (61.6% versus 43.0%, P = 0.0011) was higher in the group with LARR. Multivariate logistic regression analysis revealed that preoperative CAVI was independently associated with LARR (odds ratio, 0.60, 95% confidence interval, 0.46-0.78, P < 0.001).In patients with AF and LA enlargement, CAVI is independently associated with LA reverse remodeling after catheter ablation.

Safety and efficacy of ablation index-guided atrial fibrillation ablation in octogenarians.

BACKGROUND: Limited data on the efficacy and safety of atrial fibrillation (AF) ablation using an ablation index (AI) for octogenarians is available. We aimed to compare the efficacy and safety of AI-guided AF ablation between AF patients aged ≥80 years (Group 1) and <80 (Group 2). HYPOTHESIS: We hypothesized that AI-guided AF ablation could complete the procedure with comparable efficiency and safety in patients aged ≥80 years and <80. METHODS: We retrospectively reviewed 2087 AF patients undergoing their first AI-guided AF ablation in our hospital. We compared the atrial tachyarrhythmia (AT) recurrence and procedure-related complication rate between Group 1 (n = 193) and Group 2 (n = 1894). RESULTS: The mean age was 83.0 (interquartile range [IQR] 81.0, 84.0) years in Group 1 and 67.0 (IQR 60.0, 72.0) in Group 2. AF type was significantly different between the two groups: Of Group 1 patients, 120 (62.2%) had paroxysmal AF, 61 (31.6%) persistent AF, and 12 (6.2%) long-standing persistent AF, while of Group 2 patients, 1016 (53.6%) paroxysmal AF, 582 (30.7%) persistent AF, and 296 (15.6%) long-standing persistent AF (p = .001). Unadjusted AT recurrence-free survival curves showed similar AT recurrence-free survival between the two groups (p = .67 by log-rank test). After the adjustment for AF type, the survival curve was similar between them (hazard ratio, 1.24; 95% CI [0.92-1.65]; p = .15, Group 1 vs. Group 2). The rate of procedure-related complications was similar between the two groups (3.1% vs. 3.0%, respectively, p = .83). CONCLUSION: Catheter ablation guided by AI achieved similar AT recurrence and complication rates between elderly AF patients aged ≥80 years and patients <80 years.

A case of Takotsubo cardiomyopathy with apical hypertrophic cardiomyopathy-like morphological changes during recovery.

Objective: Few cases of Takotsubo cardiomyopathy with apical hypertrophic cardiomyopathy (APH)-like morphological changes during the recovery process have been reported. Patient: A 56-year-old woman diagnosed with Takotsubo cardiomyopathy showed a morphology similar to that of APH during recovery. We examined this patient using 2D speckle-tracking echocardiography based on the method used for hypertrophic cardiomyopathy, which suggested that the circumferential strain (CS) of the middle wall indicated myocardial function of the left ventricle, and the CS of the inner wall was associated with left ventricular chamber function. Results: We measured the CS of the endocardial, middle, and epicardial layers and found that the apical inner layer CS (CSinner), middle layer CS, and outer layer CS were all decreased at the onset. CSinner showed a strong tendency to recover on echocardiography performed when APH-like morphology was observed. Conclusion: The morphology of the apex in our case likely contributed to the maintenance of chamber function.

A case of acute coronary syndrome caused by delayed coronary ischemia after transcatheter aortic valve implantation.

An 84-year-old female patient suffered from dyspnea due to severe aortic stenosis. Several comorbidities and her advanced age made her acceptable for transcatheter aortic valve implantation (TAVI). The TAVI procedure was performed via a femoral access and a 26-mm CoreValve prosthesis (Medtronic, Minneapolis, MN, USA) was implanted. The prosthesis was deployed at a high position because of short distance between the annulus base and coronary arteries. Aortic angiography indicated normal contrast flow into both coronary arteries. Six months later she was readmitted to our hospital because of acute coronary syndrome. Although selective intubation of coronary arteries could not be achieved because of high valve position, both coronary arteries seemed to be well contrasted. As a consequence, the second coronary angiography was undertaken because of recurring chest pains. The aortic root angiogram showed a decreased contrast flow into both coronary arteries. During the examination she deteriorated rapidly, developed cardiopulmonary arrest, and a percutaneous cardiopulmonary support and an intra-aortic balloon pump needed to be inserted. She was then transferred to the operating room for aortic valve replacement. This is the first case of delayed coronary ischemia after TAVI, necessitating the removal of an implanted CoreValve and its replacement with a new prosthetic valve. .

Evaluation of safety and efficacy of periprocedural use of rivaroxaban and apixaban in catheter ablation for atrial fibrillation.

BACKGROUND: We previously reported that dabigatran increased the risk of microthromboembolism and hemopericardium compared with warfarin. The safety of non-vitamin-K-antagonist oral anticoagulants (NOACs) in the periprocedural use of atrial fibrillation (AF) ablation is controversial. This study aimed to compare the incidence of asymptomatic cerebral microthromboembolism and hemopericardium in AF ablation among periprocedural use of rivaroxaban, apixaban, and warfarin. METHODS AND RESULTS: This study was a prospective, randomized registry. Patients taking NOACs upon visiting our hospital were randomly assigned into 2 groups; rivaroxaban and apixaban. Warfarin was continued in patients taking warfarin. Asymptomatic cerebral microthromboembolism was evaluated by magnetic resonance imaging on the day after the ablation procedure. In 176 consecutive patients (101 paroxysmal, and 75 persistent AF), rivaroxaban was used in 55, apixaban in 51, and warfarin in 70. There were no symptomatic cerebral infarctions in this study. Asymptomatic cerebral microthromboembolism was detected in 32 (18.4%) patients; nine (16.4%) with rivaroxaban, 10 (20%, p=0.80; vs. rivaroxaban) with apixaban, and 13 (18.8%, p=0.81; vs. rivaroxaban) with warfarin. Hemopericardium occurred in 5 (2.8%) patients; 2 with rivaroxaban, 1 with apixaban (p=1.0; vs. rivaroxaban), and 2 with warfarin (p=1.0; vs. rivaroxaban). In multivariate analysis, concomitant coronary angiography (p<0.05, odds ratio 5.73) was a predictor of cerebral thromboembolism. CONCLUSIONS: The incidence of asymptomatic cerebral microthromboembolism and hemopericardium in AF ablation is similar among the periprocedural use of rivaroxaban, apixaban, and warfarin.

The optimal setting of complex fractionated atrial electrogram software in substrate ablation for atrial fibrillation.

BACKGROUND: Complex fractionated atrial electrogram (CFAE)-targeted catheter ablation (CFAE ablation) requires a high rate of atrial fibrillation (AF) termination to provide good outcomes. We determined the optimal settings of CFAE software. METHODS: In our 430 consecutive patients, AF was terminated in 97 (234/242) and 79% (149/188) of patients with paroxysmal and persistent AF, respectively, by CFAE ablation combined with (31%) or without (69%) pulmonary vein isolation, occasionally with nifekalant infusion. We analyzed 109 consecutive patients who underwent CFAE ablation to determine the optimal settings for comparing subjective versus objective decisions by the CFAE software on CARTO3. We compared three settings: the default setting (0.05-0.15 mV, 50-120 ms) and two modified settings (#1: 0.05-0.30 mV, 40-70 ms, #2: 0.05-0.13 mV, 10-20 ms). We retrospectively analyzed 11,425 points during left atrial mapping before ablation and 10,306 points that were subjectively detected and ablated as CFAE points. An interval confidence level ≥6 denoted a site with CFAE. RESULTS: With the default setting, the accuracy, sensitivity, specificity, positive productive value, and negative productive values were 67, 42, 77, 48, and 73%, respectively. With modified setting #1, the values were 78, 55, 87, 74, and 77%, respectively, versus 64, 82, 60, 53, and 91%, respectively, for modified setting #2. CONCLUSION: These data suggest that setting #1 was generally superior to the default setting, whereas setting #2 was optimal for excluding areas not requiring ablation. The optimal CFAE software setting was a voltage of 0.05-0.30 mV and an interval parameter of 40-70 ms.