Acute procedural safety of the latest radiofrequency ablation catheters in atrial fibrillation ablation: Data from a large prospective ablation registry.

BACKGROUND: Safety data of the latest radiofrequency (RF) technologies during atrial fibrillation (AF) ablation in real-world clinical practice are limited. OBJECTIVES: We sought to evaluate the acute procedural safety of the four latest ablation catheters commonly used for AF ablation. METHODS: A total of 3957 AF ablation procedures performed between January 2022 and December 2023 at 20 centers with either the THERMOCOOL SMARTTOUCH SF (STSF), TactiCath (TC), QDOT Micro (QDM), or TactiFlex (TF) were retrospectively analyzed. RESULTS: In total, QDM, STSF, TF, and TC were used in 343 (8.7%), 1793 (45.3%), 1121 (28.4%), and 700(17.7%) procedures. Among 2406 index procedures, electrical pulmonary vein isolations were successfully achieved in 99.5%. Despite similar total procedure times in the four groups, the total fluoroscopic time was significantly shorter for QDM/STSF with CARTO than TF/TC with EnSite (18.7 ± 14 vs. 27.6 ± 20.6 min, p < .001) and longest in the TF group. The incidence of cardiac tamponade was 0.7% (0.5% and 0.9% during index and redo procedures, 0.8% and 0.3% for paroxysmal and non-paroxysmal AF) and was significantly lower for QDM/STSF than TF/TC (0.2% vs. 1.1%, p = .008) and highest in the TF group. The incidence of cardiac tamponade was higher for TF than TC and STSF than QDM. In the multivariate analysis, TF/TC with EnSite was a significant independent predictor of cardiac tamponade during both the index (odds ratio [OR] = 4.8, 95% confidence interval [CI] = 1.3-17.5, p = .02) and all procedures (OR = 3.0, 95% CI = 1.3-7.2, p = .01). CONCLUSIONS: The incidence of cardiac tamponade and the fluoroscopic time during AF ablation significantly differed among the latest RF catheters and mapping systems in real-world clinical practice.

Incidence of phrenic nerve injury during pulmonary vein isolation using different cryoballoons: data from a large prospective ablation registry.

AIMS: Phrenic nerve injury (PNI) is the most common complication during cryoballoon ablation. Currently, two cryoballoon systems are available, yet the difference is unclear. We sought to compare the acute procedural efficacy and safety of the two cryoballoons. METHODS: This prospective observational study consisted of 2,555 consecutive atrial fibrillation (AF) patients undergoing pulmonary vein isolation (PVI) using either conventional (Arctic Front Advance) (AFA-CB) or novel cryoballoons (POLARx) (POLARx-CB) at 19 centers between January 2022 and October 2023. RESULTS: Among 2,555 patients (68.8 ± 10.9 years, 1,740 men, paroxysmal AF[PAF] 1,670 patients), PVIs were performed by the AFA-CB and POLARx-CB in 1,358 and 1,197 patients, respectively. Touch-up ablation was required in 299(11.7%) patients. The touch-up rate was significantly lower for POLARx-CB than AFA-CB (9.5% vs. 13.6%, p = 0.002), especially for right inferior PVs (RIPVs). The touch-up rate was significantly lower for PAF than non-PAF (8.8% vs. 17.2%, P < 0.001) and was similar between the two cryoballoons in non-PAF patients. Right PNI occurred in 64(2.5%) patients and 22(0.9%) were symptomatic. It occurred during the right superior PV (RSPV) ablation in 39(1.5%) patients. The incidence was significantly higher for POLARx-CB than AFA-CB (3.8% vs. 1.3%, P < 0.001) as was the incidence of symptomatic PNI (1.7% vs. 0.1%, P < 0.001). The difference was significant during RSPV (2.5% vs. 0.7%, P < 0.001) but not RIPV ablation. The PNI recovered more quickly for the AFA-CB than POLARx-CB. CONCLUSIONS: Our study demonstrated a significantly higher incidence of right PNI and lower touch-up rate for the POLARx-CB than AFA-CB in the real-world clinical practice.

Geriatric nutritional risk index as a predictor of arrhythmia recurrence after catheter ablation of atrial fibrillation.

BACKGROUND AND AIMS: The nutritional risk of patients who undergo atrial fibrillation (AF) ablation varies. Its impact on the recurrence after ablation is unclear. We sought to evaluate the relationship between the nutritional risk and arrhythmia recurrence in patients who undergo AF ablation. METHODS AND RESULTS: We enrolled 538 patients (median 67 years, 69.9% male) who underwent their first AF ablation. Their nutritional risk was evaluated using the pre-procedural geriatric nutritional risk index (GNRI), and the patients were classified into two groups: No-nutritional risk (GNRI â‰§ 98) and Nutritional risk (GNRI < 98). The primary endpoint was a recurrence of an arrhythmia, and its relationship to the nutritional risk was evaluated. We used propensity-score matching to adjust for differences between patients with a GNRI-based nutritional risk and those without a nutritional risk. A nutritional risk was found in 10.6% of the patients, whereas the remaining 89.4% had no-nutritional risk. During a mean follow-up of 422 days, 91 patients experienced arrhythmia recurrences. The patients with a nutritional risk had a significantly higher arrhythmia recurrence rate both in the entire study cohort (Log-rank p = 0.001) and propensity-matched cohort (Log-rank p = 0.006). In a Cox proportional hazard analysis, the nutritional risk independently predicted arrhythmia recurrences in the entire study cohort (hazard ratio [HR]: 3.91, 95% confidence interval [CI]: 1.84-8.35, p < 0.001) and propensity-matched cohort (HR: 6.49, 95% CI: 1.42-29.8, p = 0.016). CONCLUSION: A pre-procedural malnutrition risk was significantly associated with increased arrhythmia recurrences in patients who underwent AF ablation.

Exercise-induced ventricular tachycardia in a case with hypertrophic cardiomyopathy taking cibenzoline.

We report a 17-year-old woman with hypertrophic cardiomyopathy (HCM) successfully resuscitated from ventricular fibrillation while taking cibenzoline. During exercise-stress testing before implanting an implantable cardioverter-defibrillator, ventricular tachycardia was induced and thought to be a proarrhythmia due to the use-dependent effect of the Na channel blockade with cibenzoline. In patients with arrhythmogenic substrates such as HCM, it is critical to pay attention to the proarrhythmic effects of class I antiarrhythmic drugs while increasing heart rate.

Torsade de pointes induced by intravenous amiodarone therapy accompanied by marked augmentation of the transmural dispersion of repolarization in a patient with tachycardia-induced-cardiomyopathy.

We report a 77-year-old human on renal dialysis for end-stage renal disease with heart failure and atrial fibrillation (AF) complicated by a high ventricular frequency. The underlying disease was thought as tachycardia-induced-cardiomyopathy. Intravenous infusion of amiodarone was initiated, and direct current cardioversion succeeded in converting AF to sinus rhythm. Then, excessive increases in the QT and Tpeak-Tend (Tp-e) intervals were seen and hypokalemia induced by hemodialysis led to the development of numerous episodes of torsades de pointes (TdP). Magnesium repletion was effective in preventing TdP, while Tp-e intervals returned to the previous values 2 days after the discontinuation of amiodarone.

Vagal Reactions During Laser Balloon Ablation in Patients with Paroxysmal Atrial Fibrillation.

Radiofrequency and cryoballoon applications around the pulmonary veins (PVs) could provoke a vagal reflex (VR) by modulating the intrinsic cardiac autonomic nervous system (ICANS).This study aimed to investigate the incidence, timing, and clinical impact of a VR provoked by a laser balloon application for a PV isolation (PVI).A total of 92 consecutive paroxysmal atrial fibrillation (PAF) patients underwent a laser balloon PVI of PAF. Acute changes in the heart rate and blood pressure were recorded. The heart rate variability (HRV) was tested by Holter ECGs before and at three months following the ablation. Three hundred forty-five out of 363 PVs were successfully isolated (97%) with laser balloon applications. A VR such as sinus bradycardia (26.1%), transient sinus arrest (9.8%), transient atrioventricular block (1.1%), or a blood pressure reduction (8.7%) was observed during the laser balloon applications for the PVI. The follow-up ended at 12 months. The HRV attenuation was comparable before and at three months after the ablation procedure between that with and without a VR (P = 0.14). The PAF recurrence rate was also comparable between the two groups (P = 0.882).The laser balloon PVI often provoked a VR, however, the modulation of the ICANS was temporary and for up to three months as measured by the HRV changes after the ablation, and the freedom from any atrial fibrillation recurrence was comparable regardless of the occurrence of a VR.

Endocardial contact mapping of the left atrial appendage in persistent atrial fibrillation.

INTRODUCTION: Isolation of the left atrial appendage (LAA) is often performed in persistent atrial fibrillation (AF). Propagation patterns in the LAA during AF remain to be elucidated. We sought to characterize propagation patterns in the LAA during AF in persistent AF. METHODS: Persistent AF patients undergoing catheter ablation were studied. Pulmonary vein isolation (PVI) was performed during continuous AF. If AF was not terminated by PVI, bi-atrial mapping was performed using a multi-electrode catheter during AF. Maps were collected at each site for 30 seconds and analyzed offline with a novel software, CARTOFINDER. This software made automatic determinations of whether activation was focal or rotational. The left atrium (LA) was divided into five regions, of which the LAA was one, and the right atrium (RA) into three. RESULTS: Eighty patients were studied (62 ± 10 years, 65 males). On average, 9.6 ± 2.2 and 4.1 ± 1.2 maps were created in the LA and RA, respectively. The LAA was mapped in 70 patients, resulting in 85 maps. In the LAA, activation was identified as focal more often than rotational (64 [91%] vs 10 [14%] patients, P < .001), seven patients displayed both. The number of focal activation events was greatest in the LAA (28.5 events/30 seconds [interquartile range, 15-54]) of the eight atrial regions. During focal activation, sites designated as earliest activation frequently covered a wide area, rather than being localized to a discrete site (5.4 ± 3.1 electrodes). CONCLUSIONS: The results of this study suggest that focal activation is a major mechanism underlying the arrhythmogenicity of the LAA in persistent AF.

Clinical investigation of the durability of the lesions created by left atrial linear ablation with a cryoballoon.

INTRODUCTION: Pulmonary vein isolation (PVI) and linear ablation with a roof line and bottom line on the left atrial (LA) posterior wall (LAPW) can be achieved with a cryoballoon (CB). This study sought to investigate the long-term durability of these linear lesions. METHODS AND RESULTS: Among 290 persistent patients with atrial fibrillation (AF) who had undergone linear ablation with a CB on the roof and bottom line of the LAPW in addition to the PVI, we analyzed those patients who underwent a re-do AF ablation. Arrhythmia recurrence was confirmed in 70 (24%) out of 290 patients, and 47 (16%) patients underwent re-do sessions. At the beginning of the re-do ablation, we examined the reconnection sites of the linear lesions on the LAPW and PVI. Maintenance of the conduction block on the LAPW roof and bottom lines was observed in 35 out of 47 patients (74.5%), and 16 out of 35 patients (45.7%), respectively. The length of the roof line was significantly shorter in patients with preservation of the conduction block on the LAPW roof than in those without (36.2 ± 6.5 mm vs 41.6 ± 4.7 mm, P = .02). CONCLUSION: Durable lesions could be obtained after linear ablation with the CB for the LAPW roof line, especially in those with a relatively short LAPW roof line. However, patients requiring touch-up ablation with radiofrequency were included, and that was associated with a potential financial implication.

Impact of intensively lowered low-density lipoprotein cholesterol on deferred lesion prognosis.

OBJECTIVES: The aim of this study was to investigate the impact of intensively lowered low-density lipoprotein cholesterol (LDL-C) level on the deferred lesion prognosis after revascularization deferral based on fractional flow reserve (FFR). BACKGROUND: Lowering LDL-C is associated with lower cardiovascular event rate, but its benefit on the deferred lesion prognosis has not been well evaluated. METHODS: This retrospective, single-center, observational study analyzed 192 deferred lesions with FFR value >0.80 in 192 patients with stable coronary artery disease. According to the first follow-up LDL-C level, they were assigned to the LOW group (<70 mg/dL) or the HIGH group (≥70 mg/dL). Deferred lesion failure (DLF) was defined as the composite of deferred lesion revascularization and deferred vessel myocardial infarction. RESULTS: Of all participants, 61 and 131 patients were assigned to the LOW and the HIGH group, respectively. During the median follow-up of 2.8 years, DLF occurred in 1 and 14 patients in the LOW group and the HIGH group (1.6% and 10.7%, log-rank p = .043), respectively. The incidence of any unplanned revascularization was also significantly lower in the LOW group than in the HIGH group (3.3% vs. 14.5%, log-rank p = .032). CONCLUSIONS: The incidence of DLF was significantly lower in the patients with LDL-C < 70 mg/dL than in those with LDL-C ≥ 70 mg/dL at the first follow-up after FFR-based deferral of revascularization.

Efficacy and Safety of Left Atrial Appendage Closure With WATCHMAN in Japanese Nonvalvular Atrial Fibrillation Patients　- Final 2-Year Follow-up Outcome Data From the SALUTE Trial.

BACKGROUND: The SALUTE trial was a prospective, multicenter, single-arm trial to confirm the safety and efficacy of the WATCHMAN left atrial appendage closure (LAAC) device for stroke prevention in patients with nonvalvular atrial fibrillation (NVAF) in Japan.Methods and Results:A total of 54 subjects (including 12 roll-in subjects) with a WATCHMAN implant procedure were followed in 10 investigational centers. Follow-up visits were performed up to 2 years post-implant. The baseline CHA2DS2-VASc score was 3.6±1.6 and the baseline HAS-BLED score was 3.0±1.1. All 42 subjects in the intention to treat (ITT) cohort underwent successful implantation of the LAAC device without any serious complications, achieving the prespecified performance goal. The effective LAAC rate was maintained at 100% from 45 days to 12 months post-implant, achieving the prespecified performance goal. During follow-up, 1 subject died of heart failure, and 3 had ischemic strokes, but there were no cases of hemorrhagic stroke or systemic embolism. All events were adjudicated as unrelated to the WATCHMAN device/procedure by the independent Clinical Events Committee. All 3 ischemic strokes were classified as nondisabling based on no change in the modified Rankin scale score. CONCLUSIONS: Final results of the SALUTE trial demonstrated that the WATCHMAN LAAC device is an effective and safe alternative nonpharmacological therapy for stroke risk reduction in Japanese NVAF patients who are not optimal candidates for lifelong anticoagulation. (Trial Registration: clinicaltrials.gov Identifier NCT03033134).

Chemical mapping as a predictor of vein of Marshall ethanol ablative effects.

PURPOSE: The aim of this study was to test regional pharmacological effects of an antiarrhythmic agents to predict ablative effects. BACKGROUND: The vein of Marshall (VOM) providing vascular access to myocardial tissue has been used for ablative purposes using ethanol. METHODS: A total of 35 patients (male 21, 63.2 ± 7.8 years old) were included. A balloon-tipped infusion catheter was inserted into the VOM. Endocardial ultrahigh-resolution mapping was performed along the VOM region to record the change in atrial electrograms (AEs) after VOM injection of cibenzoline of 3.5 mg during sustained atrial fibrillation (AF). Subsequently, ethanol was infused into the VOM and ablative region was mapped. RESULTS: In 17 patients (49 %), cibenzoline reduced AEs amplitude by >50%, all of which had also complete elimination of AEs following ethanol (Group A). In 18 patients (Group B), cibenzoline failed to eliminate AEs; yet, in 13 of 18 AEs were eliminated by ethanol. In the remaining five patients, ethanol did not eliminate AE. CONCLUSIONS: Cibenzoline into the VOM could reliably predicts the results of subsequent ethanol infusion into the VOM using ultrahigh-resolution mapping system, which leads to avoid unnecessary permanent lesion creation by ethanol infusion.

A Survey of Direct Oral Anticoagulant Cessation in General Surgery and Outcomes in Patients with Nonvalvular Atrial Fibrillation.

There is little data on management and outcomes of atrial fibrillation (AF) patients on direct oral anticoagulants (DOAC) undergoing general surgery.We retrospectively assessed 98 surgeries in 85 nonvalvular AF patients aged 73 ± 8 (59 men) receiving DOACs. Cardiac, emergency, and minimally invasive surgeries were excluded.The CHA2DS2-VASc score ranged from 0 to 8. The DOACs being given were: dabigatran, 16; rivaroxaban, 25; apixaban, 28; and edoxaban, 16. While the DOACs were not suspended in 11 cases, they were interrupted for a median of 2.0 days before surgery and restarted at a median of 3.0 days after surgery. There were 9 complications (9.2%), 3 instances of thromboembolism and 6 bleeding. Thromboembolism occurred at a mean of 3.0 postoperative days, all of which occurred before resumption of DOACs, while bleeding events occurred at a mean of 4.0 postoperative days. Two of the 3 patients with thromboembolism went into cardiopulmonary arrest during the event, but were resuscitated. There were significantly more patients with congestive heart failure or combined antiplatelets in the patients with complications. The complication group had a significantly higher HAS-BLED score and lower preoperative hemoglobin level. There were no significant differences in the management of DOAC interruption between those with complications and without.The perioperative complication rate in nonvalvular AF patients undergoing elective surgery treating with DOACs was 9.2%. Patients with congestive heart failure, receiving combined therapy with antiplatelets, a higher HAS-BLED score, or lower preoperative hemoglobin level were at higher risk. Further studies evaluating the ideal perioperative DOAC protocol are warranted.

Experimental Study with Regard to the Effects of Energy Titration of the Laserballoon on the Lesion Creation Using Porcine Myocardium.

Laserballoon-based pulmonary vein isolation has proven to be safe and effective. However, the influence of the laser energy titration on the lesion formation has never been fully investigated. The aim of this study was to determine the relationship between the delivered laser energy and lesion size, as well as the incidence of steam pop.The whole porcine heart was excised, and the left ventricular myocardium was separated into four specimens. Myocardial specimens were embedded in a warm mattress to keep the myocardial temperature around 37°C. The laserballoon was located so that the surface of the laserballoon was attached to the myocardium. The laser energy was irradiated against the surface of myocardium at 5.5, 8.5, 10.0, and 12.0 W for 3, 5, 10, and 20 seconds. The depth, surface area, and lesion volume were measured using a digital vernier caliper.At constant laser energy and time, the lesion size increased significantly with the increasing energy (P < 0.001) and application duration (P < 0.001). The steam pop was provoked when a 12.0 W laser energy was applied for longer than 16 seconds, and it occurred in 2 out of 8 lesions.The laserballoon demonstrated the ability to create a lesion formation in a dose- and time-dependent manner. Steam pop could be provoked with high-energy irradiation.

Blood Coagulation Status during Cryofreezing Ablation and Effects of the Direct Anticoagulants Dabigatran and Edoxaban.

Cryoballoon ablation is an established catheter-based approach to treat atrial fibrillation (AF). However, thromboembolic events cannot be avoided during cryoablation. There is little data regarding the blood coagulation status during freezing.The thrombin antithrombin complex (TAT) and prothrombin fragment 1+2 (F 1+2) of patient blood were measured during cryoballoon application when the cryoballoon temperature reached the nadir in 63 AF patients. TAT was also measured from porcine blood during cryoballoon freezing in 5 pigs.The TAT and F 1+2 increased from 6.60 ± 5.65 to 9.16 ± 7.28 ng/mL (P = 0.004) and from 279.6 ± 146.4 to 323.6 ± 169.1 pmol/L (P = 0.003) between the control and during freezing, respectively. The TAT increased from 0.46 to 0.87 ng/mL during freezing compared to that of pre-freezing (P < 0.05), and it returned to 0.39 ng/mL in 30 minutes after an intravenous edoxaban administration (N.S.).Dabigatran failed to exert sufficient anticoagulant effects during cryofreezing. In contrast, intravenous edoxaban seemed to provoke anticoagulation effects under extreme low temperature circumstances.

Long-Term Performance of Right Ventricular Implantable Cardioverter-Defibrillator Leads in Arrhythmogenic Right Ventricular Cardiomyopathy and Hypertrophic Cardiomyopathy.

Patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) and hypertrophic cardiomyopathy (HCM) implanted with implantable cardioverter-defibrillators (ICDs) may show a large decrease in R-wave amplitude during long-term follow-up. However, it is unclear whether this decrease is higher in these patients than in those without structural heart disease. This study investigated ICD-lead intracardiac parameters over a long duration in patients with ARVC and HCM and compared these parameters with those of a control group. We included 50 patients (mean age, 55.2 ± 17.2 years; 26% female) with ICD leads in the right ventricular apex, and compared 7 ARVC and 14 HCM patients with 29 control patients without structural heart disease. ICD-lead parameters, including R-wave amplitude, pacing threshold, and impedance during follow-up, were compared. The difference in these parameters between the time of implantation and year 5 were also compared. There were no significant differences in R-wave amplitude at implantation among the 3 groups. The change in R-wave amplitude between the time of implantation and year 5 was significantly greater in the ARVC group (-3.3 ± 5.4 mV, P = 0.012) in comparison to the control group (1.3 ± 2.8 mV); the HCM group showed no significant difference (-0.4 ± 2.3 mV, P = 0.06). Thus, in the ARVC group, R-wave amplitude at year 5 was significantly lower than that in the control group (5.7 ± 4.8 mV versus 12.5 ± 4.5 mV, P = 0.001). In ARVC patients with ICDs, ventricular sensing is likely to deteriorate during long-term follow-up; however, in HCM patients, sensing may not deteriorate.

Cryofreezing catheter ablation of adenosine triphosphate sensitive atrial tachycardia.

INTRODUCTION: Adenosine triphosphate (ATP) sensitive atrial tachycardia (AT) has been treated by radiofrequency catheter ablation. Cryofreezing energy has emerged as a novel energy source for catheter ablation. The aim of this study was to investigate the efficacy and safety of cryofreezing ablation for ATP-sensitive AT. METHODS AND RESULTS: A total of six patients with ATP-sensitive ATs were included in this study. A single atrial extrastimulation was able to initiate and terminate these ATs in all six patients. The electrophysiological findings satisfied the diagnostic criteria of ATP-sensitive AT. The ablation catheter was located at the earliest activation site of atrial excitation during the AT, and cryofreezing energy was delivered through a cryoablation catheter to perform cryomapping at temperature of -30 or -80°C. When cryomapping successfully terminated the ATs, cryoablation at a temperature of -80°C was subsequently performed. The earliest atrial activation during AT was recorded at the Koch's triangle area associated with a distinct intra-atrial activation sequence from that recorded during ventricular pacing. Cryoablation was performed at successful cryomapping sites and resulted in the complete elimination of the AT in all six patients without affecting the bidirectional atrioventricular (AV) nodal conduction. CONCLUSION: Cryofreezing energy was safe and effective in treating ATP-sensitive ATs even in patients with its origins located in the vicinity of the AV node.

Impact of electrical connections between ipsilateral pulmonary veins on the second-generation cryoballoon ablation procedure.

BACKGROUND: Electrical connections between ipsilateral pulmonary veins (PVs) have been reported histologically and electrophysiologically. This study investigated the impact of electrical connections between ipsilateral PVs on PV isolation using second-generation cryoballoons (CB2-PVI). METHODS: Five hundred eleven atrial fibrillation patients, without any PV anomalies, underwent CB2-PVI using one 28-mm balloon and a single 3-minute freeze strategy without any bonus applications. RESULTS: Overall, 1966 of 2044 (96.2%) PVs were isolated exclusively by using 28-mm cryoballoons. Among them, 13 left superior PV (LSPVs) and two right superior PV were not persistently isolated by the first application despite a complete vein occlusion, but were isolated by subsequent applications targeting other ipsilateral PVs. Among the 13 LSPVs, six were transiently isolated by 87 (62-146) second time-to-isolation LSPV applications, but were immediately reconnected after the application. The nadir balloon temperature during the LSPV application was similar between the 13 LSPVs not isolated by the LSPV application but were not so by subsequent left inferior PV (LIPV) applications and the 488 LSPVs persistently isolated by LSPV applications (-49.4℃ ± 4.3℃ vs -50.8℃ ± 5.1℃; P = 0.328). In 59 patients in whom the initial LSPV application failed despite a complete occlusion, LIPVs were targeted for the second applications in 31 patients, and both the LSPV and LIPV were simultaneously isolated in 13 of 31 (41.9%). CONCLUSIONS: Electrical connections between ipsilateral PVs could have an impact on the CB2-PVI procedure. When the vein isolation failed despite a complete occlusion, especially for left ipsilateral PVs, it was reasonable to target the other ipsilateral PV instead of repeatedly targeting the same vein.

Differences in the electrophysiological findings of repeat ablation between patients who first underwent cryoballoon ablation and radiofrequency catheter ablation for paroxysmal atrial fibrillation.

INTRODUCTION: Several studies have revealed that second-generation cryoballoon (CB)-based pulmonary vein (PV) isolation is noninferior to radiofrequency (RF)-based PV isolation for patients with drug-refractory paroxysmal atrial fibrillation (AF). However, electrophysiological differences in repeat ablation remain unclear. METHODS AND RESULTS: This study examined electrophysiological differences during the repeat ablation between patients who first underwent RF catheter ablation and CB ablation; PV durability and non-PV AF foci were assessed for these patients. We enrolled 919 and 491 patients who underwent CB ablation (CB group) and RF catheter ablation (RF group), respectively, for paroxysmal AF between January 2013 and June 2017 at our institution. PV isolation using RF ablation involved the left atrium (LA) antrum and part of the LA posterior wall. After 2 years of follow-up, 62 and 80 patients in the CB and RF groups, respectively, underwent repeat ablation. PV reconnections were more frequent in the RF group than in the CB group (left superior PV: 46.2% and 14.5%, P < .001; left inferior PV: 35.0% and 11.2%, P = .001; right superior PV: 40.0% and 22.6%, P = .031; right inferior PV: 36.2% and 19.4%, P = .039; PVs: 39.8% and 16.9%, P < .001). LA AF foci were more frequent in the CB group than in the RF group (27.4% and 7.5%; P = .002). Other non-PV foci were prevalent in both groups. CONCLUSION: Fewer LA-PV reconnections occurred with CB ablation. However, extensive PV isolation may eliminate many LA AF foci.

The clinical impact of the left atrial posterior wall lesion formation by the cryoballoon application for persistent atrial fibrillation: Feasibility and clinical implications.

INTRODUCTION: The left atrial (LA) posterior wall (LAPW) has been targeted to improve the clinical outcomes in patients with persistent atrial fibrillation (PersAF). This study aimed to investigate the feasibility, safety, and clinical implications of cryoballoon (CB) applications on the LAPW to accomplish electrical isolation (EI) of the LAPW with CB. METHODS: A total of 100 patients (males, 84; mean age, 64 ± 10 years) with PersAF were enrolled. The first 50 patients underwent only pulmonary vein isolation (PVI) (PVI-only group) and the remaining 50 patients underwent PVI and EI of the LAPW with CB (EI-LAPW group). RESULTS: One-year sinus rhythm maintenance probability was significantly higher in the EI-LAPW group than in PVI-only group (80.0% vs 55.1%, P = 0.01). The success rate of constructing an LA roof block line (LA-RB), bottom block line, and EI of the LAPW was 92%, 60%, and 58%, respectively. The nadir CB temperature (-45°C ± 4°C vs -39°C ± 5°C, P = 0.005) and anatomical angle of the left atrial roof (106°C ± 30°C vs 144°C ± 17°C, P < 0.001) significantly predicted the successful LA-RB construction. The left ventricular ejection fraction was significantly higher in unsuccessful cases than in successful cases of an EI of the LAPW (64% ± 8% vs 58% ± 11%, P = 0.041). Even though the EI of the LAPW was unsuccessful, CB freezing in LAPW significantly debulked the nonscar area (≥0.1 mV) in LAPW (18.1 ± 5.6 vs 2.2 ± 3.1 cm 2 , P < 0.001) and provided the equivalent 1-year outcome of successful cases (79.3% vs 81.0%, P = 0.90). CONCLUSION: The combination of PVI and EI of the LAPW with CB provided better clinical outcomes than conventional PVI procedure for patients with PersAF.

Long-Term Efficacy and Safety of Everolimus-Eluting Stent Implantation in Japanese Patients with Acute Coronary Syndrome: Five-Year Real-World Data from the Tokyo-MD PCI Study.

BACKGROUND: The long-term safety of first-generation drug-eluting stent (DES) in acute coronary syndrome (ACS) was controversial. PURPOSE: The purpose of this study was to establish 5-year real-world data regarding the long-term efficacy and safety of second-generation DES in Japanese patients with ACS. METHODS: The Tokyo-MD PCI study is a multicenter, observational cohort study enrolling consecutive patients who underwent everolimus-eluting stent (EES) implantation. The 5-year clinical events were compared between the ACS group (n = 644) and the stable coronary artery disease (SCAD) group (n = 1255). The primary efficacy endpoint was ischemia-driven target lesion revascularization (TLR), and the primary safety endpoint was the composite of all-cause death or myocardial infarction (MI). RESULTS: The median follow-up duration was 5.4 years. The cumulative incidence of ischemia-driven TLR was similar between ACS and SCAD (1 year: 3.0% versus 2.7%; P=0.682, 1-5 years: 2.7% versus 2.9%; P=0.864). The cumulative incidence of all-cause death or MI within 1 year was significantly higher in ACS than in SCAD (7.4% versus 3.8%; P < 0.001); however, ACS did not increase the risk of all-cause death or MI after adjusting confounders (adjusted hazard ratio, 1.260; 95% confidence interval, 0.774-2.053; P=0.352). From 1 to 5 years, the cumulative incidence of all-cause death or MI was not significantly different between ACS and SCAD (11.6% versus 11.4%; P=0.706). The cumulative incidence of very late stent thrombosis was low and similar between ACS and SCAD (0.2% versus 0.2%; P=0.942). CONCLUSION: This real-world registry suggested that EES has comparable long-term efficacy and safety in patients with ACS and SCAD.