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.

Fibromuscular dysplasia of the brachial artery in patients with spontaneous coronary artery dissection: a case series and literature review.

Spontaneous coronary artery dissection (SCAD) is diagnosed in a very small percentage of patients with suspected acute coronary syndromes who undergo emergency coronary angiography. Although fibromuscular dysplasia (FMD) is known to coexist in patients with SCAD, the vascular sites of FMD and their frequency have not yet been clarified. We retrospectively reviewed the medical records of 16 patients who were diagnosed with and treated for SCAD at our hospital between 1 January 2011 and 31 January 2023. We have summarized their baseline and clinical characteristics and medical variables, including coronary and upper extremity angiography and in-hospital outcomes. One of our patients had concurrent cardiac tamponade requiring pericardial drainage, and another went into hemorrhage shock the following day from dissection of the gastric retroperitoneal artery. Characteristic angiographic features of partial or diffuse nonatherosclerotic stenosis were observed mainly in the distal parts of the coronary arteries or their branches. Notably, in six patients with SCAD who underwent upper extremity angiography, FMD of the brachial artery was revealed. For the first time, to our knowledge, we found a high prevalence of multifocal FMD of the brachial artery in patients with SCAD.

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.

Incidence, Risk Factors, and Treatment of Venous Thromboembolism after a Serious Disaster: The Kumamoto Twin Earthquakes.

Objective: On April 16, 2016, earthquakes struck Kumamoto. In this report, the incidence and treatment of venous thromboembolism (VTE) in patients presenting to our hospital are summarized. Materials and Methods: We reviewed the details of 22 consecutive patients who were diagnosed with VTE at our hospital during the 2 weeks after the earthquakes. Results: Nineteen of the 22 patients stayed in their cars overnight after the earthquakes. Particularly, during the first 4 days, seven consecutive patients were hospitalized for pulmonary thromboembolism. All seven patients had sheltered in their cars after the earthquakes. The two patients transported on days 2.42 and 3.54 were the most severe cases. One patient was admitted after emergency initiation of venoarterial extracorporeal membrane oxygenation for treatment of hemodynamic collapse, whereas the other patient was admitted after resuscitation. By contrast, deep vein thrombosis (DVT) alone occurred within 5-9 days of the earthquakes. Bilateral DVT was the most common, which was followed by DVT on the right side only. Conclusion: The incidence of VTE might be higher after an earthquake, and an overnight stay in a car might be a risk factor for VTE. Stable patients based on the D-dimer concentration can be managed with nonwarfarin oral anticoagulants.

Cryoballoon ablation for paroxysmal atrial fibrillation in Japan: 2-year safety and efficacy results from the Cryo AF Global Registry.

PURPOSE: Catheter ablation is a recommended rhythm control therapy after failed or intolerant antiarrhythmic drug (AAD) treatment for patients with atrial fibrillation (AF). This study evaluates clinical performance and safety of pulmonary vein isolation (PVI) using the cryoballoon (Arctic Front Advance) in Japan. METHODS: Cryo AF Global Registry is a prospective, multi-center registry. Patients with paroxysmal AF (PAF) were treated at 10 Japanese hospitals. Efficacy was evaluated by freedom from a ≥ 30-s recurrence of AF/atrial flutter (AFL)/atrial tachycardia (AT), AF-related symptoms, and quality of life using the EQ-5D-3L questionnaire. The safety endpoint was serious device- and procedure-related adverse events. RESULTS: The study included 352 patients with PAF (65 ± 10 years of age, 36% female, 36% without prior failure of AAD). Mean duration since first diagnosis of AF was 3.0 ± 5.5 years. Serious device- and procedure-related adverse event rate was 2.6% (95% CI: 1.2-4.8%). Freedom from AF/AFL/AT was 88.5% (95% CI: 84.7-91.4%) at 12 months and 86.7% (95% CI: 81.1-90.8%) at 24 months. The number of patients with ≥ 1 AF symptom was significantly decreased from 88% at enrollment to 22% (p < 0.01) at 12-month follow-up. General quality of life using EQ-5D did not improve significantly after 12 months in the summary score. However, in the visual analog scale score, there was improvement (5.8 ± 18.4; p < 0.01). CONCLUSIONS: This study demonstrates that cryoablation used for PVI is a safe and effective treatment in real-world use for patients with PAF in Japan.

Real-time visualization of the esophagus and left atrial posterior wall by intra-left atrial echocardiography.

PURPOSE: Localization of the esophagus and the left atrium (LA) posterior wall thickness (LAPWT) should be taken into account when delivering radiofrequency energy. To validate the visualization of the esophagus and analyze LAPWT by ICE advanced into the LA in patients with atrial fibrillation (AF) undergoing ablation index (AI)-guided pulmonary vein (PV) isolation. METHODS: In 73 patients (mean age, 68 ± 12; paroxysmal AF in 45), a 3-dimensional (3D) esophagus image was created with CARTO SoundstarⓇ and its location was compared with contrast esophagography saved in Carto UNIVU™. LAPWT adjacent to the esophagus was measured at 4 levels: left superior PV (LSPV), intervenous carina (IC), left inferior PV (LIPV), and LIPV bottom. A target AI value was 260 (25 W power) on the esophagus demonstrated by ICE. RESULTS: All patients had the esophagus posterior to the left PV antrum. Creating a 3D esophagus and measurement of LAPWT with ICE was done without any complications. ICE esophagus image was completely overlapped with contrast esophagography. LAPWT (mm) was 2.8 (interquartile range, 2.5-3.2), 2.2 (1.9-2.5), 1.9 (1.8-2.1), and 2.1 (1.9-2.4) for LSPV, IC, LIPV, and LIPV bottom, respectively, while LA roof thickness was 3.2 (2.9-3.6) (P < 0.0001 by ANOVA). No residual conduction gap on the esophagus after the first circumferential PV isolation was found in 64 of 73 (88%) patients. CONCLUSIONS: ICE inserted into the LA can reliably locate and display the esophagus and its relationship to the LA. LAPWT was the thinnest at the LIPV level. AI-guided ablation targeting at AI value 260 on the esophagus seemed to be effective.

High-power application is associated with shorter procedure time and higher rate of first-pass pulmonary vein isolation in ablation index-guided atrial fibrillation ablation.

BACKGROUNDS: Ablation index (AI) is useful to complete circumferential pulmonary vein isolation (CPVI) for atrial fibrillation (AF), but the role of radiofrequency power in AI-guided CPVI remains to be elucidated. METHODS: We investigated 60 patients with AF undergoing AI-guided CPVI (mean age, 66 ± 9 years; nonparoxysmal AF in 16). The first 40 patients were randomly assigned to low-power (LP; n = 20) and medium-power (MP; n = 20) groups and the following 20 patients to high-power (HP). In LP, radiofrequency (RF) application was done at 30 W at the anterior and 20 W at the posterior left atrial (LA) wall, while in MP, it was at 40 W at the anterior and 30 W at the posterior LA wall. In HP, 50 W was applied at the anterior, 40 W at posterior LA wall and 30 W on the esophagus. At each ablation point, target AI was 400 at the anterior, 360 at the posterior LA wall, and 260 on the esophagus. RESULTS: The time to complete both-side CPVI was shortest in HP (median, 40 minutes, interquartile range [IQR], 28-63) followed by MP (58 [49-83] minutes, P = .008 vs HP) and LP (84 [72-93] minutes, P = .002 vs MP). Higher RF power application significantly increased first-pass isolation rate (55% in LP, 80% in MP and 85% in HP, P = .002) and decreased LA-PV reconnection rate (10% in LP, 8% in MP, and 0% in HP, P = .03). CONCLUSION: In AI-guided PVI, the HP RF application can shorten the time to complete PVI with a high rate of first-pass isolation and a low rate of LA-PV reconnection.

Study on the Effect of Irbesartan on Atrial Fibrillation Recurrence in Kumamoto: Atrial Fibrillation Suppression Trial (SILK study).

BACKGROUND: Experimental studies suggest that angiotensin II-receptor blockers can influence atrial remodeling and may prevent atrial fibrillation (AF). Therefore, we hypothesized that irbesartan may prevent the recurrence of AF following either catheter ablation or electrical cardioversion of AF. METHODS: Study on the Effect of Irbesartan on Atrial Fibrillation Recurrence in Kumamoto (SILK study) is a prospective, multicenter, randomized, and open-label comparative evaluation of the effects of irbesartan and amlodipine on AF recurrence in hypertensive patients with AF who are scheduled to undergo catheter ablation or electrical cardioversion of AF. The primary end point was either AF or atrial tachycardia (AT) recurrence. AF/AT recurrence was evaluated for 6 months using 24-h Holter electrocardiogram and portable electrocardiogram. The secondary endpoints included the change in blood pressure, the interval from the procedure to the first AF/AT recurrence, cardiovascular events, left atrial diameter (LAD), left ventricular ejection fraction (LVEF), and changes in the biomarkers [brain natriuretic polypeptide (BNP), high-sensitivity C-reactive protein (hs-CRP), urinary albumin/creatinine]. RESULTS: The study enrolled 98 patients (irbesartan; n=47, amlodipine; n=51). The recurrence of AF/AT was observed in 8 patients (17.0%) in the irbesartan group and in 10 patients (19.6%) in the amlodipine group. There was no significant difference in the AF/AT recurrence between the irbesartan and amlodipine groups. Blood pressure decreased similarly in both groups. There were no significant differences between the two groups as regards to the interval from the procedure to the first AF/AT recurrence, occurrence of cardiovascular events, changes in LAD and LVEF. BNP and urinary albumin/creatinine significantly decreased similarly in both groups, but no significant difference was found in hs-CRP between the two groups. CONCLUSIONS: In hypertensive patients with AF, treatment with irbesartan did not have any advantage over amlodipine in the reduction of AF/AT recurrence after catheter ablation or electrical cardioversion.

Impact of right atrial-left ventricular dual-chamber permanent pacing in patients with severely symptomatic hypertrophic obstructive cardiomyopathy.

BACKGROUND: Effective alternatives to surgical myectomy for patients with symptomatic hypertrophic obstructive cardiomyopathy (HOCM) remain unestablished. Dual-chamber (DDD) pacing was evaluated in these patients using right atrial (RA) and epicardial left ventricular (LV) leads. METHODS AND RESULTS: In 6 patients with HOCM refractory to medical therapy and conventional RA-right ventricular (RV) DDD pacing, we implanted DDD pacemakers using RA and epicardial LV leads. The baseline intraventricular pressure gradient before pacemaker implantation was 103+/-44 mmHg. The pressure gradient decreased significantly to 8+/-16 mmHg by temporary RA-LV DDD pacing (p=0.006), while it decreased only to 68+/-25 mmHg by temporary RA-RV pacing (NS). It was nearly eliminated to 1+/-2 mmHg (p=0.027) 3 months after RA-LV DDD pacemaker implantation. LV end-diastolic pressure, cardiac index and systolic aortic pressure did not change significantly. New York Heart Association class improved in all patients (p=0.023). Brain and atrial natriuretic peptide concentrations, respectively 516+/-286 and 143+/-34 pg/ml at baseline, decreased significantly to 230+/-151 and 93+/-44 pg/ml 3 months after implantation (p=0.027 and 0.028). CONCLUSION: RA-LV DDD pacemaker implantation is a useful option for patients with symptomatic HOCM.