Association Between Atrial High-Rate Episodes and Ischemic/Major Bleeding Events in Patients With a Cardiac Implantable Electronic Device　- A 10-Year, Single-Center Historical Cohort Study.

BACKGROUND: An association between atrial high-rate episode (AHRE) and stroke has been reported, although data for the Asian population are limited. This study aimed to investigate the role of AHRE in ischemic and major bleeding events in patients who underwent a cardiac implantable electronic device (CIED) procedure.Methods and Results:This single-center historical cohort study included 710 patients (age: 78±11 years, 374 women) who underwent a CIED-related procedure between October 2009 and September 2019 at Shimane Prefectural Central Hospital (median follow-up period: 4.5 [2.5, 7] years, 3439 person-years). Based on the maximum AHRE burden, patients were divided into: (1) <6 min; (2) ≥6 min to 24-h; and (3) ≥24-h groups. The cumulative incidence of ischemic (ischemic stroke, systemic embolism, and transient ischemic attack) and major bleeding (≥3 Bleeding Academic Research Consortium bleeding criteria) events after the procedure were compared. Uni- and multivariate analyses were performed to identify factors associated with these events. The incidence of both events increased with the rising AHRE burden, being significantly higher in the ≥24-h group than in the <6 min group. Multivariate analysis found age ≥85 years to be the only independent factor associated with both events. CONCLUSIONS: Longer AHRE duration is associated with a high number of major bleeding and ischemic events. Monitoring these bleeding risks is mandatory when clinicians are considering anticoagulation therapy for such patients.

Addition of a ß1-Blocker to Milrinone Treatment Improves Cardiac Function in Patients with Acute Heart Failure and Rapid Atrial Fibrillation.

BACKGROUND: Tachycardia worsens cardiac performance in acute decompensated heart failure (ADHF). We investigated whether heart rate (HR) optimization by landiolol, an ultra-short-acting ß1-selective blocker, in combination with milrinone improved cardiac function in patients with ADHF and rapid atrial fibrillation (AF). METHODS AND RESULTS: We enrolled9 ADHF patients (New York Heart Association classification IV; HR, 138 ± 18 bpm; left ventricular [LV] ejection fraction, 28 ± 8%; cardiac index [CI], 2.1 ± 0.3 L/min-1/m-2; pulmonary capillary wedge pressure [PCWP], 24 ± 3 mm Hg), whose HRs could not be reduced using standard treatments, including diuretics, vasodilators, and milrinone. Landiolol (1.5-6.0 µg/kg-1/min-1, intravenous) was added to milrinone treatment to study its effect on hemodynamics. The addition of landiolol (1.5 µg/kg-1/min-1) significantly reduced HR by 11% without changing systolic blood pressure (BP) and resulted in a significant decrease in PCWP and a significant increase in stroke volume index (SVI), suggesting that HR reduction restores incomplete LV relaxation. Administration of more than 3.0 µg/kg-1/min-1 of landiolol decreased BP, CI, and SVI. CONCLUSION: The addition of landiolol at doses of <3.0 µg/kg/min to milrinone improved cardiac function in decompensated chronic heart failure with rapid atrial fibrillation by selectively reducing HR.

Improved outcomes of cardiac resynchronization therapy with a defibrillator in systolic heart failure: Analysis of the Japan cardiac device treatment registry database.

Background: Temporal change in outcomes of heart failure patients receiving cardiac resynchronization therapy with a defibrillator (CRT-D) is unknown. Methods: We assess outcomes and underlying heart diseases of patients receiving CRT-D with analyzing database of the Japan cardiac device treatment registry (JCDTR) at the implantation year 2011-2015 and New JCDTR at the implantation year 2018-2021. Results: Proportion of nonischemic heart diseases was about 70% in both the groups (JCDTR: 69%; New JCDTR: 72%). Cardiac sarcoidosis increased with the rate of 5% in the JCDTR to 9% in the New JCDTR group. During an average follow-up of 21 months, death from any cause occurred in 167 of 906 patients in the JCDTR group (18%) and 79 of 611 patients in the New JCDTR group (13%) (adjusted hazard ratio [aHR] in the New JCDTR group, 0.72; 95% confidence interval [CI]: 0.55-0.94; p = .017). The superiority was mainly driven by reduction in the risk of noncardiac death. With regard to appropriate and inappropriate implantable cardioverter-defibrillator (ICD) therapy, there was a significant reduction in the New JCDTR group versus the JCDTR group (aHR in the New JCDTR group, 0.76; 95% CI: 0.59-0.98; p = .032 for appropriate ICD therapy; aHR in the New JCDTR group, 0.24; 95% CI: 0.12-0.50; p < .0001 for inappropriate ICD therapy). Conclusions: All-cause mortality was reduced in CRT-D patients implanted during 2018-2021 compared to those during 2011-2015, with a significant reduction in noncardiac death.

Association between the atrial tachyarrhythmia recurrence period and long-term major adverse clinical events following catheter ablation for atrial fibrillation.

Background: We previously demonstrated the clinical events in patients who underwent catheter ablation (CA) for atrial fibrillation (AF). Data on the association between the period of atrial tachyarrhythmia (ATA) recurrence after CA and long-term major adverse clinical events (MACE) remain unclear. In this study, we evaluated this issue in patients with systolic impairment (left ventricular ejection fraction < 50%) and heart failure with preserved ejection fraction (HFpEF). Methods: We retrospectively collected data from 81 patients with systolic impairment and 83 patients with HFpEF who underwent CA for AF at our institution (median follow-up: 4.9 [3.6, 6.6] years). In each group, we compared the cumulative incidence of long-term MACE (since 1 year after CA) between patients with and without ATA recurrence at three follow-up periods (3, 6 months, and 1 year after index CA). We evaluated the period of recurrence, which was the most beneficial predictor of MACE among the periods. Results: In the systolic impairment group, the cumulative long-term MACE incidence was significantly higher in patients with ATA recurrence than in those without it within 6 months and 1 year (P = 0.04 and P = 0.01, respectively). Recurrence within 1 year showed the highest feasibility for predicting long-term MACE (area under the curve with 95% confidence interval [CI]:0.73 [0.61-0.84]). However, there was no difference in the incidence of MACE between patients with and without recurrence in a group with HFpEF in each period. Conclusion: ATA recurrence within 1 year could predict long-term MACE in patients with systolic impairment, but not in patients with HFpEF.

Cardiac resynchronization therapy with a defibrillator in non-ischemic and ischemic patients for primary and secondary prevention of sudden cardiac death: Analysis of the Japan cardiac device treatment registry database.

Background: Panoramic studies in patients with cardiac resynchronization therapy with a defibrillator (CRT-D) focusing on the etiology and indication are scarce. Besides, a controversy exists regarding requirement of a defibrillator in non-ischemic patients for primary prevention with CRT. Methods: Annual trends of de novo CRT-D implantations from 2011 to 2020 and outcomes of those between January 2011 and August 2015 were analyzed from the Japan cardiac device treatment registry (JCDTR) and New JCDTR database. Results: From 2011 to 2020, 8062 CRT-D recipients were registered, whose dominant indication was primary prevention of sudden cardiac death with a steady rate of about 70%. There was no significant temporal change of the proportion of non-ischemic patients being about 70% and 65% for primary and secondary prevention, respectively. Non-ischemic patients for primary prevention were associated with increased odds of appropriate ICD therapy [adjusted hazard ratio (aHR): 1.66; 95% confidence interval (CI): 1.01-2.75; p = .047] and reduced odds of any death (aHR: 0.66; 95% CI: 0.44-0.99; p = .046) as compared to ischemic patients. Conclusions: Proportion of non-ischemic etiology was much higher than that of ischemic one in the CRT-D cohort. Based on the higher odds of appropriate ICD therapy, non-ischemic patients for primary prevention appear to be prudently selected in Japan.

Characteristics of induced ventricular fibrillation cycle length in symptomatic Brugada syndrome patients.

BACKGROUND: Limited information is available on the ventricular fibrillation (VF) spectrum in Brugada syndrome (BS) patients. We clarified differences in the VF cycle length (CL) using fast-Fourier transformation (FFT) analysis in symptomatic and asymptomatic BS patients. METHODS AND RESULTS: VF was induced by pacing from the right ventricular (RV) apex and/or RV outflow tract (RVOT) for >8s. A 4096-point FFT analysis of results from 28 male BS patients (51.1 ± 13.7 years old) was performed. Dominant frequency (DF) from phases 1 (4s) to 6 was obtained at 2-s intervals. The average DF from surface and intracardiac electrograms (ECG: DF(ECG); ICE: DF(ICE,), respectively) was compared between symptomatic and asymptomatic patients. Symptomatic patients had a significantly shorter effective refractory period at a CL of 600 ms at the RVOT than asymptomatic patients. DF(ECG) significantly increased with phase (5.64 ± 0.32 Hz in phase 1 to 6.16 ± 0.52 Hz in phase 6) and was significantly higher in symptomatic patients than in asymptomatic patients. DF(ICE) had the same characteristics as DF(ECG). CONCLUSIONS: Induced VF in BS patients can be characterized using FFT analysis. Our data support the hypothesis that symptomatic patients have a significantly shorter VF CL than asymptomatic patients.

Impact of Atrial Tachyarrhythmia Recurrence on the Development of Long-Term Adverse Clinical Events Following Catheter Ablation in Patients With Atrial Fibrillation With Systolic Impairment: A Single-Center Observational Study.

Background Catheter ablation can improve long-term prognosis of patients with atrial fibrillation with systolic impairment. However, atrial tachyarrhythmia (ATA) recurrence increases during long-term follow-up. We aimed to investigate the impact of ATA recurrence on the development of long-term adverse clinical events following catheter ablation for atrial fibrillation and to identify predictors for the development of adverse clinical events. Methods and Results This single-center observational study included 75 patients with systolic impairment (left ventricular ejection fraction <50%) who underwent the first catheter ablation procedure for atrial fibrillation at our institution (median follow-up period: 3.5 [range: 2.4-4.7] years). We compared the cumulative incidence of adverse clinical events (all-cause death, heart failure hospitalization, stroke, or acute myocardial infarction) between the groups with and without ATA recurrence following the first and last procedures. Multivariable analyses were performed to identify predictors for developing adverse clinical events. Twenty-one patients (28%) developed adverse clinical events at a median of 2.2 (range: 0.64-2.8) years following the first procedure. The proportion of freedom from adverse clinical events following the first procedure was significantly lower in the ATA recurrence group than in the nonrecurrence group (41% [n=40] versus 95% [n=35], P<0.0005); the proportion following the last procedure also showed a similar tendency (35% [n=26] versus 57% [n=49], P<0.0001). ATA recurrence emerged as an independent predictor for adverse clinical events following both procedures after multivariable adjustment. Conclusions ATA recurrence following catheter ablation procedure could predict adverse clinical events in patients with atrial fibrillation with systolic impairment.

Prevalence and characteristics of transesophageal echocardiography-related esophageal mucosal injury in patients with atrial fibrillation who underwent pulmonary vein isolation.

BACKGROUND: Transesophageal echocardiography (TEE) is the gold standard for detecting thrombi in the left atrium (LA) and left atrial appendage (LAA) prior to pulmonary vein isolation (PVI) for the treatment of atrial fibrillation (AF). Although TEE has a good safety profile, it was recently reported that TEE preceding PVI can cause esophageal mucosal injuries (EMIs). The exact mechanism remains to be elucidated. In the present study, we investigated the incidence and risk factors of TEE-related EMI (TEE-EMI) among patients who underwent PVI for AF. METHODS AND RESULTS: This study included 262 consecutive patients who underwent PVI with preoperative TEE using a 3D TEE probe and postoperative esophagogastroduodenoscopy. TEE-EMIs were observed in 16 (6.1%) patients (18 lesions), whereas PVI-related EMIs were found in 5 (1.9%) patients (8 lesions). All TEE-EMIs were observed in the upper or middle esophagus and occurred more frequently in the right region of the upper esophagus and the left anterior region of the middle esophagus; only one patient experienced mild chest discomfort. In the multivariate analysis, advanced age was an independent risk factor for TEE-EMIs (odds ratio 1.08, 95% confidence interval 1.01-1.16; P = 0.0274). CONCLUSIONS: The incidence of TEE-EMIs with 3D TEE probes was relatively high in the upper or middle esophagus, anatomically close to the LA, among patients who underwent PVI. Advanced age could pose a significant risk. These findings may warrant consideration of other methods to rule out LA/LAA thrombi, especially in elderly patients.

The Differential Prognostic Impact of Long-Duration Atrial High-Rate Episodes Detected by Cardiac Implantable Electronic Devices between Patients with and without a History of Atrial Fibrillation.

Long-duration atrial high-rate episodes (AHREs) monitored using cardiac implantable electronic devices (CIEDs) can predict long-term major adverse cardiovascular events (MACEs). This study aimed to compare the impact of long-duration AHRE on MACE development between patients with and without a history of atrial fibrillation (AF). This single-center observational study included 132 CIED-implanted patients with AHREs detected via remote monitoring. The population was dichotomized into groups: with (n = 69) and without (n = 63) AF. In each group, cumulative incidences of MACEs comprising all-cause deaths, heart failure hospitalizations, strokes, and acute coronary syndromes were compared between patients with AHRE durations of ≥24 h and <24 h. Multivariate analysis was performed to identify predictors of MACEs among patients without AF. MACE incidence was significantly higher in patients with AHRE ≥24 h than in those with <24 h in the group without AF (92% vs. 30%, p = 0.005). MACE incidence did not significantly differ between AHRE ≥24 h and <24 h in the group with AF (54% vs. 26%, p = 0.44). After a multivariate adjustment, AHRE duration of ≥24 h emerged as the only independent predictor of MACEs among patients without AF (p = 0.03). In conclusion, a long-duration AHRE was prognostic in patients without a history of AF but not in patients with a history of AHREs.

Enhanced oxidative stress and presence of ventricular aneurysm for risk prediction in cardiac sarcoidosis.

OBJECTIVE: Sudden cardiac death (SCD) is the major cause of death in cardiac sarcoidosis (CS). We aimed to identify the prognostic markers for sustained ventricular tachycardia (sVT) and SCD in patients with CS. METHODS: We performed a prospective observational cohort study for patients with CS diagnosed according to the Japanese or Heart Rhythm Society guidelines between June 2008 and March 2020 in our hospital. The primary endpoint was a composite of the first sVT and SCD. The levels of urinary 8-hydroxy-2'-deoxyguanosine (U-8-OHdG), a marker of oxidative DNA damage that reflects the inflammatory activity of CS, other biomarkers, and indices of cardiac function and renal function were measured on admission. RESULTS: Eighty-nine consecutive patients with CS were enrolled; 28 patients with no abnormal 18F-fluorodeoxyglucose (18F-FDG) accumulation in the heart were excluded and 61 patients with abnormal 18F-FDG accumulation were followed up for a median of 46 months (IQR: 20-84). During the follow-up period, 15 of 61 patients showed sVT (n=12) or SCD (n=3). A Cox proportional hazard model showed that U-8-OHdG concentration and presence of ventricular aneurysm (VA) were independent predictors of first sVT/SCD. The cut-off U-8-OHdG concentration for predicting first sVT/SCD was 14.9 ng/mg·Cr. Patients with U-8-OHdG concentration ≥14.9 ng/mg·Cr and VA showed a significantly increased risk of sVT/SCD. CONCLUSIONS: U-8-OHdG and presence of VA were powerful predictors of first sVT/SCD in patients with CS, facilitating the stratification of cardiac events and providing relevant information about the substrates of ventricular tachycardia.

Long-term events following catheter-ablation for atrial fibrillation in heart failure with preserved ejection fraction.

AIMS: Data regarding prognostic events following catheter ablation (CA) for atrial fibrillation (AF) in patients with heart failure with preserved ejection fraction (HFpEF) are scarce. We conducted this study to compare the incidence of major adverse clinical events (MACE) following CA for AF between patients with HFpEF and those with systolic heart failure (HF). METHODS AND RESULTS: This single-centre observational study included 142 patients with HF who underwent CA for AF (median follow-up: 4.0 [2.6, 6.3] years). The patients were grouped based on the presence of HFpEF (n = 84) and systolic HF (left ventricular ejection fraction <50%, n = 58). We compared the cumulative incidence and incidence rate of MACE, comprising all-cause death, unplanned cardiovascular hospitalization (CVH), and HF hospitalization (HFH) between both groups and the number of HFH before and after CA in each group. Multivariate analysis was performed to identify the predictors of MACE in patients with HFpEF. The incidence of MACE was comparable between the groups (following the first procedure: HFpEF: 23%, 4.7/100 person-years, vs. systolic HF: 28%, 6.6/100 person-years, P = 0.18; last procedure: 20%, 4.8/100 person-years, vs. 24%, 6.9/100 person-years, P = 0.21). Although the incidence of HFH was lower in patients with HFpEF than in those with systolic HF (first procedure: 14%, 2.9/100 person-years, vs. 24%, 5.7/100 person-years, P = 0.07; last procedure: 11%, 2.5/100 person-years, vs. 24%, 6.9/100 person-years, P = 0.01), the incidence of CVH was higher (first procedure: 8%, 1.7/100 person-years, vs. 5%, 1.2/100 person-years, P = 0.74; last procedure: 6%, 1.4/100 person-years, vs. 2%, 0.5/100 person-years, P = 0.4). The number of HFH significantly decreased in both groups after CA (HFpEF: 1 hospitalization [the first and third quartiles: 0, 1] in pre-CA, vs. 0 hospitalizations [0, 0] in post-CA, P < 0.0001; systolic HF: 1 hospitalization [0, 1], vs. 0 hospitalizations [0, 0], P < 0.005). The proportion of HFH among total clinical events was significantly smaller in patients with HFpEF than in those with systolic HF (following the first procedure: 56% vs. 88%, P < 0.005; last procedure: 52% vs. 92%, P < 0.005). CONCLUSIONS: CA for AF could be beneficial for patients with HFpEF, similar to those with systolic HF. However, clinical events other than HFH should be considered cautiously in such patients.

Current status and role of programmed ventricular stimulation in patients without sustained ventricular arrhythmias and reduced ejection fraction: Analysis of the Japan cardiac device treatment registry database.

BACKGROUND: The aim of this study was to clarify the current status and role of programmed ventricular stimulation in patients without sustained ventricular arrhythmias and reduced left ventricular ejection fraction (LVEF). METHODS: The follow-up data of the Japan cardiac device treatment registry (JCDTR) was analyzed in 746 patients with LVEF ≦35% and no prior history of sustained ventricular arrhythmias who underwent de novo implantable cardioverter-defibrillator (ICD) or cardiac resynchronization therapy with a defibrillator (CRT-D) implantation between January 2011 and August 2015. RESULTS: Electrophysiological study (EPS) with programmed ventricular stimulation had been performed before the device implant in 118 patients (15.8%, EPS group). During the mean follow-up of 21 ± 12 months, the rate of freedom from any death and appropriate defibrillator therapy was not significantly different between EPS group (n = 118) and No EPS group (n = 628). NYHA class II-IV, and QRS duration were negatively associated with performing EPS. Among patients in the EPS group, the rate of ventricular tachycardia (VT)/ventricular fibrillation (VF) induction was 48%. The inducibility was not a predictor of appropriate defibrillator therapy, whereas BNP ≧535 pg/mL and no use of amiodarone were significantly associated with a risk of the appropriate therapy. CONCLUSION: EPS for induction of VT/VF had been performed in about 16% of patients with reduced LVEF before primary prevention ICD/CRT-D implantation. Elevated BNP levels and no use of amiodarone, but not inducibility of VT/VF, appeared to be associated with appropriate defibrillator therapy in these populations.

An impact of superior vena cava isolation in non-paroxysmal atrial fibrillation patients with low voltage areas.

BACKGROUND: This study aimed to investigate the correlation between left atrial low-voltage areas (LVAs) and an arrhythmogenic superior vena cava (SVC) and the impact on the efficacy of an empiric SVC isolation (SVCI) along with a pulmonary vein isolation (PVI) of non-paroxysmal atrial fibrillation (non-PAF) with or without LVAs. METHODS: We retrospectively enrolled 153 consecutive patients with non-PAF who underwent a PVI alone (n = 51) or empiric PVI plus an SVCI (n = 102). Left atrial voltage maps were constructed during sinus rhythm to identify the LVAs (<0.5 mV). An arrhythmogenic SVC was defined as firing from the SVC and an SVC associated with the maintenance of AF-like rapid SVC activity. RESULTS: An arrhythmogenic SVC and LVAs were identified in 28% and 65% of patients with a PVI alone and 36% and 73% of patients with a PVI plus SVCI, respectively (P = .275 and P = .353). In the multivariate analysis a female gender, higher pulmonary artery systolic pressure (PAPs), and arrhythmogenic SVC were associated with the presence of LVAs. In the PVI plus SVCI strategy, there was no significant difference in the atrial tachyarrhythmia/AF-free survival between the patients with and without LVAs after initial and multiple sessions (50% vs. 61%; P = .386, 73% vs. 79%; P = .530), however, differences were observed in the PVI alone group (27% vs. 61%; P = .018, 49% vs. 78%; P = .046). CONCLUSIONS: The presence of LVAs was associated with an arrhythmogenic SVC. An SVCI may have the potential to compensate for an impaired outcome after a PVI in non-PAF patients with LVAs.

Trends in the use of implantable cardioverter-defibrillator and cardiac resynchronization therapy device in advancing age: Analysis of the Japan cardiac device treatment registry database.

BACKGROUND: Trends of de novo implantation of cardiac implantable electronic devices (CIEDs) including implantable cardioverter-defibrillator (ICD) and cardiac resynchronization therapy with a defibrillator (CRT-D) or pacemaker (CRT-P) in advancing age are unknown. METHODS: Analysis of data from the Japan cardiac device treatment registry (JCDTR) with an implantation date between January 2006 and December 2016 was performed focusing on advancing age of ≧75 years. RESULTS: The cohort included 17 564 ICD, 9470 CRT-D and 1087 CRT-P recipients for de novo implantation. The rate of patients ≧75 years of age increased from 17.1% to 20.5% in ICD implantation (P = .052), from 19.7% to 30.0% in CRT-D implantation (P < .0001), and from 40.0% to 64.0% in CRT-P implantation (P = .17). There was an apparent increase in the percentage of nonischemic patients aged ≧75 years receiving ICD (10.9% in 2006 to 16.4% in 2016, P = .0008) and CRT-D (17.1% in 2006 to 27.8% in 2016, P = .0001). The implantation for primary prevention ICD (P = .059) and CRT-D (P = .012) was also associated with a temporal increase in the percentage of patients aged ≧75 years. CONCLUSIONS: Proportion of patients ≧75 years of age for de novo CIED implantation gradually increased from 2006 to 2016, presumably because of the growing number of nonischemic cardiomyopathy and heart failure patients requiring primary prevention of sudden cardiac death.

Incidence and risk factors for cardiac implantable electronic device infection in current clinical settings in a Japanese population: A 20-year single-center observational study.

BACKGROUND: The incidence of cardiac implantable electronic device (CIED) infection is increasing worldwide. However, data regarding this phenomenon in Japan and information on factors associated with developing CIED infection are limited. Our aim was to compare the incidence of CIED infection between pre-current (past 10-20 years) and current (past 10 years) clinical settings and to investigate risk factors for CIED infection in current clinical settings in a Japanese population. METHODS: This observational study included 1749 patients (age 77 ± 12 years, 824 males) who underwent a CIED-related procedure between August 1999 and July 2019 at our institution. We defined the pre-current and current clinical setting periods as August 1999-July 2009 (period I) and August 2009-July 2019 (period II), respectively. We compared the incidence rate of CIED infection between periods and evaluated the risk factors for CIED infection in period II by multivariate analysis. RESULTS: A CIED infection was identified in 0.7% (5/709 patients) and 1.7% (17/1040) of patients in periods I and II, respectively. Notably, the rate of late (>6 months since last procedure) CIED infection was significantly increased in period II (1.3% vs. 0.1%, p < 0.01), despite the rate of early infection (≤6 months) being comparable (0.4% vs. 0.6%, p = 0.58). On multiple logistic regression, revision [odds ratio (95% confidence interval): 5.2 (1.6-16.3), p = 0.005] and age [0.96, (0.93-0.99), p = 0.007] were identified as independent risk factors for CIED infection in period II. CONCLUSIONS: Our findings suggest that the increasing incidence of CIED infection in current clinical settings was due to an increase in late CIED infection. Furthermore, revision and younger age were identified as independent risk factors for CIED infection in current clinical settings. Our data indicate that clinicians should consider whether the merit of a procedure can overcome the risk of infection when planning revision or implantation in younger patients.

Correlation between asymptomatic gastroesophageal excessive transmural injury after pulmonary vein isolation and a bonus freeze protocol using the second-generation 28-mm cryoballoon for paroxysmal atrial fibrillation.

BACKGROUND: Second-generation cryoballoon (2G-CB) ablation is highly effective for achieving pulmonary vein isolation (PVI) with a promising clinical outcome. However, the ideal freezing strategy for preventing gastroesophageal excessive transmural injury (ETI) remains under debate. This study aimed to clarify the correlation between gastroesophageal ETI and a bonus-freeze protocol after PVI using 2G-CBs. METHOD: This study included 100 patients who underwent PVI using 2G-CB followed by an endoscopic examination. The freeze-cycle duration was set at 180s. In the first 33 patients a 120s bonus-freeze was applied after successful PVI (bonus group), while in the following 67 the bonus freeze was omitted (non-bonus group). Early freezing interruption was performed when the esophageal temperature reached 25°C. Gastroesophageal ETI was defined as any injury that resulted from the PVI, including esophageal damage or periesophageal nerve injury. RESULTS: Gastroesophageal ETIs were observed in 9 (27.3%) and 6 (9.0%) patients and were all asymptomatic, esophageal damage in 3 and 0, and periesophageal nerve injury in the remaining 6 and 6 in the bonus group and non-bonus group, respectively (p=0.033). In the multivariate analysis, the bonus freeze protocol (odds ratio 3.527; 95% confidence interval 1.110-11.208; p=0.033) was the sole independent predictor of gastroesophageal ETI. During a one-year follow-up 26 of 33 bonus group patients (78.8%) and 52 of 67 (77.6%) non-bonus group patients remained in stable sinus rhythm without any differences between the groups. CONCLUSIONS: In the patients with a bonus-freeze protocol using the 2G-CB, gastroesophageal ETIs were detected more often than in those with the non-bonus freeze protocol. In contrast, freedom from atrial fibrillation after the 2G-CB based PVI was comparable when applying either a bonus or non-bonus freeze protocol.

Pilsicainide-induced Brugada-type ECG and ventricular arrhythmias originating from the left posterior fascicle in a case with Brugada syndrome associated with idiopathic left ventricular tachycardia.

The patient was a 50-year-old male in 2002, who was first suspected of having a Brugada-type electrocardiogram (ECG). A drug challenge test using pilsicainide was performed and unmasked a typical coved type ST elevation followed by ventricular arrhythmias (VAs) manifesting a QRS pattern with a right bundle branch block and left axis deviation. Three years later, he was transferred to the emergency room due to a wide QRS tachycardia with the same QRS morphology as the VA that previously occurred in the drug challenge test. An ECG just after the recorded termination of the tachycardia exhibited a typical Brugada-type ECG. In an electrophysiological study, ventricular fibrillation could be easily induced with reproducibility. Since the clinical tachycardia could not be sustained by an isoproterenol infusion, mapping and catheter ablation targeting the pilsicainide-induced VAs was performed. The successful ablation site was the left mid-lower septal wall where a Purkinje potential was recorded and a false tendon was attached just to it.