Difference between antegrade and retrograde orbital atherectomy system debulking using an artificial pulsatile heart model.

BACKGROUND: Debulking devices are necessary to treat severe calcified lesions. OAS has a unique characteristic that the burr moves forward and backward. There are few studies reporting the differences of ablation style between only-antegrade and only-retrograde OAS. AIMS: The aim of this study was to evaluate the difference of ablation style between only-antegrade and only-retrograde orbital atherectomy system (OAS) using an artificial pulsatile heart model (HEARTROID system®) and optical coherence tomography (OCT). METHODS: The calcified lesion model was inserted into the mid of left anterior descending in the HEARTROID®. Only-antegrade and only-retrograde ablation of OAS were conducted for each five lesions. Pre-OCT, OCT after low speed debulking and OCT after high speed debulking were conducted. The width and the depth of debulked area, the debulked area and the direction of debulked area were investigated. RESULTS: In all of 210 cross-sections, 91 debulked cross sections were chosen for analysis. Only-antegrade group had 47 debulked cross-sections, and only-retrograde group 44 cross-sections. In the evaluation of OCT after high speed debulking, the debulked area (0.76 mm2 [0.58-0.91] vs. 0.53 mm2 [0.36-0.68], p < 0.001) and the depth of debulked area (0.76 mm [0.58-0.91] vs. 0.53 mm [0.36-0.68], p < 0.001) were significantly higher in only-antegrade group compared to only-retrograde group. The debulked bias and the width of debulked area are not significantly different between the two groups. CONCLUSIONS: Compared to only-retrograde debulking, only-antegrade debulking acquired larger debulked area because of larger cutting depth, although the debulked bias and the width of debulked area were comparable between the two groups.

Impact of left atrial appendage flow velocity on thrombus resolution and clinical outcomes in patients with atrial fibrillation and silent left atrial thrombi: insights from the LAT study.

AIMS: Blood stasis is crucial in developing left atrial (LA) thrombi. LA appendage peak flow velocity (LAAFV) is a quantitative parameter for estimating thromboembolic risk. However, its impact on LA thrombus resolution and clinical outcomes remains unclear. METHODS AND RESULTS: The LAT study was a multicentre observational study investigating patients with atrial fibrillation (AF) and silent LA thrombi detected by transoesophageal echocardiography (TEE). Among 17 436 TEE procedures for patients with AF, 297 patients (1.7%) had silent LA thrombi. Excluding patients without follow-up examinations, we enrolled 169 whose baseline LAAFV was available. Oral anticoagulation use increased from 85.7% at baseline to 97.0% at the final follow-up (P < 0.001). During 1 year, LA thrombus resolution was confirmed in 130 (76.9%) patients within 76 (34-138) days. Conversely, 26 had residual LA thrombi, 8 had thromboembolisms, and 5 required surgical removal. These patients with failed thrombus resolution had lower baseline LAAFV than those with successful resolution (18.0 [15.8-22.0] vs. 22.2 [17.0-35.0], P = 0.003). Despite limited predictive power (area under the curve, 0.659; P = 0.001), LAAFV ≤ 20.0 cm/s (best cut-off) significantly predicted failed LA thrombus resolution, even after adjusting for potential confounders (odds ratio, 2.72; 95% confidence interval, 1.22-6.09; P = 0.015). The incidence of adverse outcomes including ischaemic stroke/systemic embolism, major bleeding, or all-cause death was significantly higher in patients with reduced LAAFV than in those with preserved LAAFV (28.4% vs. 11.6%, log-rank P = 0.005). CONCLUSION: Failed LA thrombus resolution was not rare in patients with AF and silent LA thrombi. Reduced LAAFV was associated with failed LA thrombus resolution and adverse clinical outcomes.

Appropriate Selection of Substrate Ablation for Persistent Atrial Fibrillation Using Intraprocedural Assessment.

BACKGROUND: It has not been fully elucidated which patients with persistent atrial fibrillation (PerAF) should undergo substrate ablation plus pulmonary vein isolation (PVI). This study aimed to identify PerAF patients who required substrate ablation using intraprocedural assessment of the baseline rhythm and the origin of atrial fibrillation (AF) triggers.Methods and Results: This was a post hoc subanalysis using extended data of the EARNEST-PVI trial, a prospective multicenter randomized trial comparing PVI-alone and PVI-plus (i.e., PVI with added catheter ablation) arms. We divided 492 patients into 4 groups according to baseline rhythm and the location of AF triggers before PVI: Group A (n=22), sinus rhythm with pulmonary vein (PV)-specific AF triggers (defined as reproducible AF initiation from PVs only); Group B (n=211), AF with PV-specific AF triggers; Group C (n=94), sinus rhythm with no PV-specific AF trigger; Group D (n=165), AF with no PV-specific AF trigger. Among the 4 groups, only in Group D (AF at baseline and no PV-specific AF triggers) was arrhythmia-free survival significantly lower in the PVI-alone than PVI-plus arm (P=0.032; hazard ratio 1.68; 95% confidence interval 1.04-2.70). CONCLUSIONS: Patients with sinus rhythm or PV-specific AF triggers did not receive any benefit from substrate ablation, whereas patients with AF and no PV-specific AF trigger benefited from substrate ablation.

Changes in QRS morphology during antidromic atrioventricular reentrant tachycardia.

We report a case of a 44-year-old male who underwent an electrophysiological study for symptomatic supraventricular tachycardia (SVT) with wide QRS complex. The SVT was diagnosed as an antidromic atrioventricular reentrant tachycardia (AVRT) via antegrade conduction of left-sided accessory pathway (AP). However, the QRS morphology changed during the SVT, and then the SVT was terminated spontaneously. The mapping of AP was performed during sinus rhythm, and the radiofrequency application successfully eliminated the AP, which rendered tachycardias non-inducible. This was a rare case of antidromic AVRT during which the QRS morphology changed.

Predictors and outcomes of tricuspid regurgitation improvement after radiofrequency catheter ablation for persistent atrial fibrillation.

INTRODUCTION: Little has been reported on the predictors and outcomes of improvement of tricuspid regurgitation (TR) after radiofrequency catheter ablation (RFCA) for persistent atrial fibrillation (AF). METHODS: We enrolled 141 patients with persistent AF and moderate or severe TR assessed by transthoracic echocardiography (TTE) who underwent an initial RFCA between February 2015 and August 2021. These patients underwent follow-up TTE at 12 months after the RFCA, and were categorized into two groups based on the improvement (defined as at least one-grade improvement of TR) and non-improvement of TR: IM group and Non-IM group, respectively. We compared the patient characteristics, ablation procedures, and recurrences after the RFCA between the two groups. In addition, we examined the major event (defined as admission for heart failure or all-cause death) more than 12 months after the RFCA. RESULTS: IM group consisted of 90 patients (64%). A multivariate analysis revealed that age <71 years old and absence of late recurrence (LR, defined as recurrence of atrial tachyarrhythmia between 3 and 12 months after the RFCA) were independently associated with the improvement of TR after the RFCA. Furthermore, IM group had the higher incidence of major event-free survival than Non-IM group. CONCLUSIONS: Relatively young age and absence of LR were good predictors of improvement of TR after the RFCA for persistent AF. In addition, the improvement of TR was related to better clinical outcomes.

Prognostic Comparison of Octogenarian vs. Non-Octogenarian With Acute Decompensated Heart Failure　- AURORA Study.

BACKGROUND: Acute decompensated heart failure (ADHF) is the main cause of hospitalization and death of octogenarians, but no data on the 1-year post-discharge mortality rate. We evaluated the clinical status and predictors of 1-year mortality in octogenarians with ADHF.Methods and Results: From the AURORA (Acute Heart Failure Registry in Osaka Rosai Hospital) study, we examined 1,246 hospitalized ADHF patients. We compared the in-hospital mortality rate and the proportion of heart failure (HF) with preserved ejection fraction (HFpEF) between octogenarians and non-octogenarians. After discharge we compared the 1-year mortality rate between these groups, and we also evaluated the predictors of death in both groups. The proportion of HFpEF among the in-hospital deaths of octogenarians was significantly higher than in non-octogenarians (46.2% vs. 15.0%, P=0.031). The 1-year mortality rate after discharge was significantly higher in the octogenarians than non-octogenarians (P=0.014). Multivariable Cox regression analysis revealed that albumin ≤3.0 g/dL and antiplatelet agents were useful predictors of 1-year death after discharge of octogenarians whereas chronic kidney disease was a predictor in the non-octogenarians. CONCLUSIONS: The proportion of HFpEF among in-hospital deaths of octogenarians with ADHF was high as compared with non-octogenarians. When octogenarians with ADHF have severe hypoalbuminemia and antiplatelet agents, early nutritional and medical interventions after discharge may be important to improve the 1-year prognosis.

Impact of Structural Abnormalities in Left Ventricle and Left Atrium on Clinical Outcomes in Heart Failure with Preserved Ejection Fraction.

Two key echocardiographic parameters, left ventricular mass index (LVMI) and left atrial volume index (LAVI), are important in assessing structural myocardial changes in heart failure (HF) with preserved ejection fraction (HFpEF). However, the differences in clinical characteristics and outcomes among groups classified by LVMI and LAVI values are unclear.We examined the data of 960 patients with HFpEF hospitalized due to acute decompensated HF from the PURSUIT-HFpEF registry, a prospective, multicenter observational study. Four groups were classified according to the cut-off values of LVMI and LAVI [LVMI = 95 g/m2 (female), 115 g/m2 (male) and LAVI = 34 mL/m2]. Clinical endpoints were the composite of HF readmission and all-cause death. Study endpoints among the 4 groups were evaluated. The composite endpoint occurred in 364 patients (37.9%). Median follow-up duration was 445 days. Kaplan-Meier analysis revealed significant differences in the composite endpoint among the 4 groups (P < 0.001). Cox proportional hazards analysis demonstrated that patients with increased LAVI alone were at significantly higher risk of HF readmission and the composite endpoints than those with increased LVMI alone (P = 0.030 and P = 0.024, respectively). Age, male gender, systolic blood pressure at discharge, atrial fibrillation (AF) hemoglobin, renal function, and LAVI were significant determinants of LVMI and female gender, AF, hemoglobin, and LVMI were significant determinants of LAVI.In HFpEF patients, increased LAVI alone was more strongly associated with HF readmission and the composite of HF readmission and all-cause death than those with increased LVMI alone.

High-density activation map of atrial tachycardia within left atrial appendage.

Identification of the critical isthmus of the reentrant tachycardia is essential to maximize the effect of catheter ablation (CA) and to minimize the myocardial injury of CA. An 81-year-old woman presented recurrent palpitations after CA of atrial fibrillation (AF) and atrial tachycardia (AT). She had moderate aortic valve stenosis and coronary artery disease. She had received a pulmonary vein isolation, left atrial (LA) posterior wall isolation, and LA anterior linear ablation for atrial fibrillation 1 year prior. At the start of the procedure, she was in sinus rhythm. Atrial burst pacing induced an AT (230msec). High-density mapping revealed a figure-of-eight activation pattern within the LA appendage (LAA), accounting for 99% of the tachycardia cycle length. The critical isthmus was identified at the mid LAA and the local electrogram of the critical isthmus was not fractionated. A single radiofrequency application at the critical isthmus of the AT, terminated the AT. She was free from any ATs for 28 months. Radiofrequency ablation of the localized reentrant AT was usually performed targeting long fractionated electrograms. In our case, the local electrogram at the critical isthmus was not fragmented compared with the LAA distal part. Long fractionated electrograms were recorded at a more distal part of the LAA than the common isthmus and we could avoid the potential risk of a perforation. A recent developed 3-dimensional electro-anatomical mapping system can identify the critical isthmus and allow us to select a new therapeutic strategy for a critical isthmus ablation of an AT within the LAA.

Sex Differences in the Efficacy of Pulmonary Vein Isolation Alone vs. Extensive Catheter Ablation in Patients With Persistent Atrial Fibrillation.

BACKGROUND: Women experience more severe arrhythmogenic substrates. This study hypothesized that an extensive ablation strategy, such as linear ablation and/or complex fractionated atrial electrogram (CFAE) ablation in addition to pulmonary vein isolation (PVI-plus), might be effective for women, whereas the PVI alone strategy (PVI-alone) might be sufficient for men to maintain sinus rhythm. The aim of this study was to test this hypothesis.Methods and Results: This study is a post-hoc subanalysis of the EARNEST-PVI trial focusing on sex differences in the efficacies of different ablation strategies. The EARNEST-PVI trial was a prospective, multicenter, randomized, and open-label non-inferiority trial in patients with persistent AF. The primary endpoint was recurrence of AF, atrial flutter, or atrial tachycardia. The EARNEST-PVI trial randomized 376 (76%) men (PVI-alone 186, PVI-plus 190) and 121 (24%) women (PVI-alone 63, PVI-plus 58). The event rate was significantly lower for men and numerically lower for women in the PVI-plus than the PVI-alone group, and there was no interaction between men and women (hazard ratio, 0.641; 95% confidence interval, 0.417-0.985; P value, 0.043 for men vs. hazard ratio, 0.661; 95% confidence interval, 0.352-1.240; P value, 0.197 for women; P value for interaction, 0.989). CONCLUSIONS: The superiority of the extensive ablation strategy vs. the PVI-alone strategy for persistent AF was consistent across both sexes.

The correlation between local impedance drop and catheter contact in clinical pulmonary vein isolation use.

INTRODUCTION: Local impedance (LI) drop during radiofrequency (RF) application is monitored to assess the lesion formation. Recently, a novel ablation catheter has been introduced to clinical setting, which is capable of monitoring LI and catheter contact parameters including contact force (CF) and contact angle (CA). This study aimed to clarify the correlation between LI drop and catheter contact parameters. METHODS AND RESULTS: This prospective study included 15 paroxysmal atrial fibrillation (AF) patients who underwent initial pulmonary vein isolation (PVI). First-pass encircling point-by-point PV ablation was performed by using a 4.5-mm irrigated ablation catheter, with monitoring LI, CF, and CA. RF energy was applied for 30 s at each site with 30 W. Stable ablation points were analyzed to examine the correlation between LI drop and catheter contact parameters. Among 903 ablation points, 499 stable ablation points (55.2%) were analyzed. CA showed good correlation with LI drop (ρ = 0.418, p < .001). Maximum CF, minimum CF, average CF, and initial CF all showed weak correlation with LI drop (ρ = 0.201, p < .001; ρ = 0.224, p < .001; ρ = 0.258, p < .001; and ρ = 0.212, p < .001, respectively). Multivariate analysis demonstrated that CA was an independent factor of LI drop among the catheter contact parameters (ß = 0.139, 95% CI = 0.111-0.167, p < .001). The LI drop in the blocked segments was significantly higher than that in the electrical conduction gap segments (27.3 ± 9.8 vs. 19.6 ± 6.4 Ω, p < .001) CONCLUSION: In clinical PVI use, both CF and CA were correlated with LI drop. More parallel CA could induce higher LI drop, which may lead to effective lesion formation.

Impact of very early recurrence of atrial fibrillation after cryoballoon ablation.

BACKGROUND: Although much has been discussed about the early recurrence of atrial fibrillation (ERAF) after cryoballoon ablation (CBA), the clinical impact of very early recurrence of atrial fibrillation (VERAF) after CBA remains unclear. This study aimed to investigate the impact of VERAF after CBA. METHODS: We enrolled 236 consecutive patients who underwent an initial CBA for paroxysmal atrial fibrillation between February 2017 and December 2020 in our hospital. These patients were categorized into three groups: VERAF group who experienced an initial recurrence of atrial tachyarrhythmia within 48 h after CBA, late-ERAF (LERAF) group who experienced an initial recurrence of atrial tachyarrhythmia between 48 h and 3 months after CBA, and non-ERAF (NERAF) group who did not experience a recurrence of atrial tachyarrhythmia within 3 months after CBA. We investigated the late recurrence of AF (LRAF, defined as recurrence of atrial tachyarrhythmia more than 3 months after CBA), and the incidence of non-pulmonary vein (PV) triggers in the patients who experienced a repeat ablation procedure due to LRAF. RESULTS: VERAF group had a higher incidence of freedom from LRAF than LERAF group (p = 0.032) and a lower incidence of freedom from LRAF than NERAF group (p = 0.002). Moreover, VERAF group had the highest incidence of non-PV triggers at repeat ablation procedure among the three groups (p = 0.003). CONCLUSIONS: While ERAF was a predictor of LRAF, VERAF was less related to LRAF among the patients with ERAF after CBA. Furthermore, VERAF might be associated with non-PV triggers.

Impact of cryoballoon contact angle and acute myocardial injury on pulmonary vein reconnection.

At present, it remains unclear whether the effect on cryoinjury can be strongly exerted by contact of the balloon with the pulmonary vein (PV) ostium. The present study included 204 paroxysmal atrial fibrillation (PAF) patients who underwent an initial pulmonary vein isolation (PVI) using a cryoballoon from the Osaka Rosai Atrial Fibrillation ablation (ORAF) registry. The total balloon contact angle was measured from the equator line (sum of the angles of the upper side and bottom side in all PVs) under fluoroscopic imaging. The patients were stratified into three tertile groups according to the total balloon contact angle. We evaluated the relationship between the total balloon contact angle and clinical outcomes, including the value of acute myocardial injury marker (high-sensitive cardiac troponin I [hs-TnI]), arrhythmia recurrence, and PV reconnections in the repeated ablation. The total balloon contact angle was significantly associated with the hs-TnI value among the tertile groups (p < 0.001) and a multiple regression analysis showed that the total balloon contact angle significantly correlated with the hs-TnI value (standardized beta-coefficient = 0.572, p < 0.001). The balloon contact angle in PVs with PV reconnections was significantly lower than in those without (p = 0.044), while no significant differences in the recurrence of atrial fibrillation among the tertile groups were observed in the enrolled patients. The total balloon contact angle was significantly associated with the acute myocardial injury marker, hs-TnI. The total balloon contact angle was significantly associated with PV reconnections after cryoballoon ablation in patients who underwent a repeat ablation.

Impact of radiofrequency catheter ablation for atrial fibrillation in patients with left atrial enlargement.

Little has been reported on the impact of radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) in patients with left atrial enlargement (LAE). A total of 706 patients underwent an initial RFCA for AF between September 2014 and September 2019 in our hospital. These patients were categorized into two groups according to the pre-procedural left atrial diameter (LAD) measured by transthoracic echocardiography (TTE): LAE group with LAD ≥ 50 mm and non-LAE group with LAD < 50 mm. We compared the patient characteristics, ablation procedures, and late recurrence of AF (LRAF, defined as a recurrence of atrial tachyarrhythmia between 3 and 12 months after the RFCA) between the two groups. In addition, we performed follow-up TTE at 12 months after RFCA and investigated the factors associated with left atrium (LA) reverse remodeling in each group. LAE group and non-LAE group consisted of 155 and 551 patients, respectively. There were no significant differences in ablation procedures, procedure-related complications, and the incidence of LRAF between the two groups. Furthermore, non-PAF was identified as an independent predictor of LA reverse remodeling in LAE group by multiple regression analysis (P = 0.020). RFCA might be an effective and safe procedure even in patients with LAD ≥ 50 mm, using the contemporary 3D-guided mapping and ablation technologies. Moreover, RFCA can lead to LA reverse remodeling in 1 year if they have non-PAF before ablation.

Acute myocardial injury after radiofrequency catheter ablation: impact on pulmonary vein reconnection and relevant factors.

Radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) causes myocardial injury and induces high-sensitive cardiac troponin I (hs-TnI) release into the systemic circulation. Several factors are considered to be associated with myocardial injury after ablation, but few studies showed the relationship between the value of myocardial injury marker after the RFCA and relevant factors. AF patients who underwent primary RFCA were enrolled from the Osaka Rosai Atrial Fibrillation ablation (ORAF) registry. The relationship between hs-TnI after the RFCA and PV reconnection (PVR) was evaluated. The impact of relevant factors, including baseline patient characteristics, detail of procedure on myocardial injury was investigated. This study included 407 patients (median age was 71 years, the ratio of female was 30.7%). Late arrhythmia recurrence was observed in 111 patients (27.3%) and 66 patients were underwent repeated ablation. PVR was observed in 33 patients (50.0%). The hs-TnI level was significantly lower in the patients with PVR than those without PVR (1.150 ng/ml vs 1.921 ng/ml, p = 0.040). Paroxysmal AF and age were significantly associated with acute myocardial injury after the RFCA (standardized beta coefficient = 0.206 and p < 0.001, standardized beta coefficient = - 0.114 and p = 0.043, respectively). The hs-TnI after RFCA was significantly higher in PAF patients than PerAF (p < 0.001), even if application number and total application time were taken into consideration. Acute myocardial injury after RFCA was significantly lower in the patients with PVR than those without PVR. Age and AF type were significantly and strongly associated with acute myocardial injury after the RFCA.

Suitable Dose of Long-Term Tolvaptan to Reduce Heart Failure Rehospitalizations.

The short-term effectiveness of tolvaptan (TLV) for heart failure (HF) has been established, but the long-term effects are controversial. We investigated HF patients who could not discontinue both loop diuretics and TLV at discharge from AURORA (Acute Heart Failure Registry in Osaka Rosai Hospital). We compared the following factors at discharge between the RH group, consisting of patients with rehospitalizations due to worsening HF within 1 year after discharge (RH group), and non-RH group: age, gender, blood pressure, history of HF admission, electrocardiogram and echocardiographic parameters, atherosclerotic risk factors, laboratory data, and medications. Furthermore, we compared the effects of long-term low-dose TLV (≤ 7.5 mg/day) and high-dose TLV on HF rehospitalizations. The RH group consisted of 81 patients (58.7%). A multivariate analysis revealed that a history of HF admission and the TLV dose were independently and significantly associated with 1-year HF rehospitalizations. A receiver operating characteristic curve revealed that 7.5 mg of TLV was a suitable cutoff value for 1-year HF rehospitalizations. The Kaplan-Meier curves demonstrated that the HF rehospitalization free ratio was significantly higher in the low-dose TLV group (≤ 7.5 mg/day) than in high-dose TLV group over 1 year.In conclusion, the TLV dose, in addition to a history of HF admission, was associated with 1-year HF rehospitalizations in diuretic-dependent HF patients. In these patients, long-term low-dose TLV (≤ 7.5 mg/day) may be favorable for reducing HF rehospitalizations.

Novel Endovascular Therapy, AGET, for In-Stent Occlusions in Iliac and Femoropopliteal Arteries.

Catheter-directed intra-arterial thrombolysis (CDT) is useful for not only patients with acute limb ischemia but also those with chronic total occlusions (CTOs) of the lower extremity arteries. However, it is difficult to determine whether CTO lesions have significant thrombi, which can be treated by CDT, or not in a clinical setting. Angioscopy can accurately detect thrombi. We investigated the clinical impact of angioscopy guided endovascular therapy following thrombolysis (AGET) for in-stent occlusions (ISOs) in iliac or femoropopliteal arteries.We performed AGET in 7 patients with ISOs whose occlusion duration was less than 1 year. We performed angioscopy to evaluate the area of the thrombi after a successful wire crossing of an ISO lesion. In addition, we performed biopsies of ISO lesions to confirm whether the angioscopic findings coincided with the histopathological findings at 20 sites. We selectively performed a continuous infusion of urokinase using a fountain infusion catheter for ISO lesions. The next day, we evaluated the lesion flow and performed intervention only at the plaque stenosis site if necessary.AGET could achieve TIMI 3 flow in all patients, and preserved a 1-year patency in 5 patients (71.4%). The angioscopic findings of thrombi and plaque perfectly coincided with the histopathological findings.In conclusion, this new endovascular therapy technique, AGET, was observed to be feasible and safe for iliac or femoropopliteal artery ISO lesions.

Electrophysiological identification of superior vena cava: Novel insight into slow conduction or conduction block.

INTRODUCTION: It has not been clarified how to identify the electrophysiological junction between right atrium (RA) and superior vena cava (SVC). The aim of this study was to identify the electrophysiological RA-SVC junction according to slow conduction or conduction bock and to examine the electrophysiological SVC isolation procedure. METHODS: Seventy-three consecutive atrial fibrillation patients who underwent SVC mapping using a CARTO 3 system were enrolled in this study. Slow conduction or conduction block between the RA and SVC was identified by adjusting the lower threshold criteria of the early meets late function and was described as a white line. The SVC isolation was performed along the white line and with pacing maneuvers to confirm direct SVC capture. RESULTS: Activation mapping (1296 ± 631 points) was obtained in 66 patients (90%) in 4.6 ± 1.8 min. Slow conduction or conduction block was observed in all patients. The threshold for detecting slow conduction or conduction block was 24 ± 8 ms. The location of the electrophysiological RA-SVC junction was higher in the anterior portion (anterior-septal, anterior, and anterior-lateral) than in the posterior portion (posterior-septal, posterior, and posterior-lateral) (-2.3 ± 6.2 mm vs. 7.1 ± 6.3 mm, p < .001). The SVC isolation at the electrophysiological RA-SVC junction was successful in all patients without any injury to the sinus node function. Asymptomatic phrenic nerve injury was observed in three patients (4.5%). CONCLUSION: In all patients, the electrophysiological RA-SVC junction determined by slow conduction or conduction block was identified and the electrophysiological SVC isolation was performed successfully and safely.

Pulmonary vein isolation alone vs. more extensive ablation with defragmentation and linear ablation of persistent atrial fibrillation: the EARNEST-PVI trial.

AIMS: Previous studies could not demonstrate any benefit of more intensive ablation in addition to pulmonary vein isolation (PVI) including complex fractionated atrial electrogram (CFAE) and linear ablation for recurrence in the initial catheter ablation of persistent atrial fibrillation (AF). This study aimed to establish the non-inferiority of PVI alone to PVI plus these additional ablation strategies. METHODS AND RESULTS: Patients with persistent AF who underwent an initial catheter ablation (n = 512, long-standing persistent AF; 128 cases) were randomly assigned in a 1:1 ratio to either PVI alone (PVI-alone group) or PVI plus CFAE and/or linear ablation (PVI-plus group). After excluding 15 cases who did not receive procedures, we analysed 249 and 248 patients, respectively. The primary endpoint was recurrence of AF, atrial flutter, and/or atrial tachycardia, and the non-inferior margin was set at a hazard ratio of 1.43. In the PVI-plus group, 85.1% of patients had linear ablation and 15.3% CFAE ablation. After 12 months, freedom from the primary endpoint occurred in 71.3% of patients in the PVI-alone group and in 78.3% in the PVI-plus group [hazard ratio = 1.56 (95% confidence interval: 1.10-2.24), non-inferior P = 0.3062]. The procedure-related complication rates were 2.0% in the PVI-alone group and 3.6% in the PVI-plus group (P = 0.199). CONCLUSION: This randomized trial did not establish the non-inferiority of PVI alone to PVI plus linear ablation or CFAE ablation in patients with persistent AF, but implied that the PVI plus strategy was promising to improve the clinical efficacy (NCT03514693).

Effect of the Balloon Size on Lesion Formation During Visually Guided Laser Balloon Ablation in an In Vitro Model.

BACKGROUND: It is unclear whether balloon size can influence lesion formation. The aim of this study was to evaluate the impact of balloon size on lesion formation during laser balloon procedures in an in vitro model.Methods and Results:Laser energy was applied to chicken muscle using a first generation laser balloon. Laser ablation was performed with 2 different balloon sizes (18 mm and 32 mm) using 2 different power settings (12 W/20 s and 8.5 W/20 s) on the chicken muscle. The lesion characteristics, including maximum lesion depth, maximum lesion diameter, surface diameter and depth at maximum diameter, were compared between the 18-mm and 32-mm balloon groups at 12 W/20 s and 8.5 W/20 s, respectively. We created 40 lesions using laser energy at 12 W/20 s and 80 lesions at 8.5 W/20 s. At both power settings, the maximum lesion depth and the depth at the maximum diameter were larger in the 18-mm than in the 32-mm balloon group. At both power settings, the maximum lesion diameter and the surface diameter were smaller in the 18-mm than in the 32-mm balloon group. CONCLUSIONS: The balloon size could affect the lesion formation during laser balloon ablation. The lesion with the larger balloon size was wider and shallower than the lesion with the smaller balloon size.

Efficacy of Extensive Ablation for Persistent Atrial Fibrillation With Trigger-Based vs. Substrate-Based Mechanisms　- A Prespecified Subanalysis of the EARNEST-PVI Trial.

BACKGROUND: Extensive ablation in addition to pulmonary vein isolation (PVI) would be effective for modification of non-pulmonary vein (non-PV) substrates, whereas PVI might be sufficient for elimination of PV triggers. This study aimed to test the hypothesis that in patients with reproducible atrial fibrillation (AF) triggered by premature atrial contractions originating only from PVs, PVI alone can be sufficient to maintain sinus rhythm.Methods and Results:This study is a prespecified subanalysis of the EARNEST-PVI randomized controlled trial. This study investigated the efficacy of the PVI-alone strategy (PVI-alone) in comparison with the extensive strategy (PVI-plus) for persistent AF with a trigger-based mechanism vs. a substrate-based mechanism. Patients were stratified into 3 groups based on AF mechanisms: (1) Substrate group (N=236); (2) PV trigger group (N=236); and (3) non-PV trigger group (N=24). The hazard ratios for AF recurrence of the PVI-alone strategy with reference to the PVI-plus strategy were 1.456 (95% confidence interval [CI] [0.864-2.452]) in the substrate group, 1.648 (95% CI 0.969-2.801) in the PV trigger group, and 0.937 (95% CI 0.252-3.488) in the non-PV trigger group. No significant interaction between ablation strategy and AF mechanism was observed (P for interaction=0.748). CONCLUSIONS: This study indicated that the efficacies of the PVI-alone strategy compared with the PVI-plus strategy were consistent across persistent AF with trigger-based and substrate-based mechanisms.