Late life-threatening arrhythmia in patients with Brugada syndrome: Results from long-term follow-up in a large Japanese cohort.

INTRODUCTION: Most patients with Brugada syndrome (BrS) are first diagnosed in their 40s, with sudden cardiac death (SCD) often occurring in their 50s. Ventricular fibrillation (VF) may occur in some patients with BrS despite having been asymptomatic for a long period. This study aimed to assess the incidence and risk factors for late life-threatening arrhythmias in patients with BrS. METHODS: Patients with BrS (n = 523; mean age, 51 ± 13 years; male, n = 497) were enrolled. The risk of late life-threatening arrhythmia was investigated in 225 patients who had experienced no cardiac events (CEs: SCD or ventricular tachyarrhythmia) for at least 10 years after study enrollment. The incidence of CEs during the follow-up period was examined. RESULTS: During the follow-up of the 523 patients, 59 (11%) experienced CEs. The annual incidences of CEs were 2.87%, 0.77%, and 0.09% from study enrollment to 3, 3-10, and after 10 years, respectively. Among 225 patients who had experienced no CEs for at least 10 years after enrollment, four patients (1.8%) subsequently experienced CEs. Kaplan-Meier analysis revealed significant differences in the incidence of late CEs between patients with and without a history of symptoms (p = .032). The positive and negative predictive values of late CEs for the programmed electrical stimulation (PES) test were 2.9% and 100%, respectively. CONCLUSION: Our results suggest that patients with BrS who are asymptomatic and have no ventricular tachycardia/VF inducibility by PES are at extremely low risk of experiencing late life-threatening arrhythmias.

Efficacy of Computed Tomography-Based Evaluation of Myocardial Extracellular Volume Combined With Red Flags for Early Screening of Concealed Cardiac Amyloidosis in Patients With Atrial Fibrillation.

BACKGROUND: The prevalence of transthyretin amyloid cardiomyopathy (ATTR-CM) in atrial fibrillation (AF) patients remains unclear. We explored the efficacy of computed tomography-based myocardial extracellular volume (CT-ECV) combined with red flags for the early screening of concealed ATTR-CM in AF patients undergoing catheter ablation. METHODS AND RESULTS: Patients referred for AF ablation at Oita University Hospital were prescreened using the red-flag signs defined by echocardiographic or electrocardiographic findings, medical history, symptoms, and blood biochemical findings. Myocardial CT-ECV was quantified in red flag-positive patients using routine pre-AF ablation planning cardiac CT with the addition of delayed-phase cardiac CT scans. Patients with high (>35%) ECV were evaluated using technetium pyrophosphate (99 mTc-PYP) scintigraphy. A cardiac biopsy was performed during the planned AF ablation procedure if 99 mTc-PYP scintigraphy was positive. Between June 2022 and June 2023, 342 patients were referred for AF ablation. Sixty-seven (19.6%) patients had at least one of the red-flag signs. Myocardial CT-ECV was evaluated in 57 patients because of contraindications to contrast media, revealing that 16 patients had high CT-ECV. Of these, 6 patients showed a positive 99 mTc-PYP study, and 6 patients were subsequently diagnosed with wild-type ATTR-CM via cardiac biopsy and genetic testing. CONCLUSIONS: CT-ECV combined with red flags could contribute to the systematic early screening of concealed ATTR-CM in AF patients undergoing catheter ablation.

Quality of epicardial adipose tissue predicts major adverse cerebral and cardiovascular events following transcatheter aortic valve implantation.

Epicardial adipose tissue (EAT) have been shown to be associated with several heart disease, including coronary artery disease (CAD), atrial fibrillation (AF), and heart failure (HF). It is reported that the quality of EAT, represented by fat attenuation determined using computed tomography (CT) imaging, can detect the histologically-assessed remodeled EAT. We tested the hypothesis that quality of EAT would predict major adverse cerebral and cardiovascular events (MACCE) following transcatheter aortic valve implantation (TAVI) in patients with aortic stenosis (AS). A total of 125 consecutive severe AS patients who underwent TAVI were enrolled (39 male, mean 85.4 ± 4.0 years). Using CT imaging before TAVI, we measured the average CT fat attenuation of EAT (EAT attenuation) and investigated the association with MACCE. During the mean follow up period of 567 ± 371 days, 21 cases of MACCE were observed. Patients with MACCE had greater levels of EAT attenuation compared to those without (- 74 ± 3.7 Hounsfield Units (HU) vs - 77 ± 5.5 HU, p = 0.010). Based on the ROC curves, the high EAT attenuation was defined as > - 74.3 HU. According to this cut-off index, 44 patients were classified into the high EAT attenuation group (28 female, mean age 87 ± 3.6 years), whereas 81 patients were classified into the low EAT attenuation group (13 female, 85 ± 4.1 years). Kaplan-Meier survival curve demonstrated that the patients in the high EAT attenuation group showed greater prevalence of MACCE (log-rank 6.64, p = 0.010). Cox proportional hazards regression analysis revealed that EAT attenuation and Logistic EuroSCORE were independently associated with the incidence of MACCE. Our results suggest that quality of EAT, assessed by EAT attenuation detected by CT imaging, can predict the cerebral and cardiovascular events after TAVI in patients with AS.

Risk stratification of ventricular fibrillation in patients with symptomatic Brugada syndrome using pharmacological tests.

BACKGROUND: Brugada syndrome (BrS), which is characterized by J-point elevation in right precordial leads of a 12-lead electrocardiogram, is associated with the occurrence of ventricular fibrillation (VF). However, risk stratification of VF in patients with BrS remains challenging. OBJECTIVE: The aim of this study was to identify a risk predictor of VF in patients with BrS using pharmacological tests. METHODS: Twenty-one consecutive patients with BrS and a history of documented spontaneous VF (n = 16) or syncope presumed to be caused by lethal ventricular arrhythmia (n = 5) were enrolled. J-wave changes in response to intravenous verapamil, propranolol, and pilsicainide were separately assessed. RESULTS: During the median follow-up period of 86.0 months, 8 patients had VF recurrence (recurrence group) and 13 patients did not have VF recurrence (non-recurrence group). Intravenous propranolol injection induced significant J-wave augmentation (i.e., increase in amplitude >0.1 mV) in the inferior and/or lateral leads in the recurrence group compared to the non-recurrence group (p = .048 and p = .015, respectively). Kaplan-Meier analysis revealed that VF recurrence is significantly higher in patients with BrS and J-wave augmentation due to intravenous propranolol than in patients without J-wave augmentation (p = .014). CONCLUSION: The study results show that propranolol-induced J-wave augmentation is involved in the risk of VF in patients with BrS. The results suggest that early repolarization patterns in response to pharmacological tests may be useful for risk stratification of VF in patients with symptomatic BrS.

Usefulness of Prehospital 12-Lead Electrocardiography System in ST-Segment Elevation Myocardial Infarction Patients in Oita　- Comparison Between Urban and Rural Areas, Weekday Daytime and Weekday Nighttime/Holidays.

BACKGROUND: We have reported that a prehospital 12-lead electrocardiography system (P-ECG) contributed to transport of suspected acute coronary syndrome (ACS) patients to appropriate institutes and in this study, we compared its usefulness between urban and rural areas, and between weekday daytime and weekday nighttime/holiday.Methods and Results: Consecutive STEMI patients who underwent successful primary percutaneous coronary intervention after using P-ECG were assigned to the P-ECG group (n=123; 29 female, 70±13 years), and comparable STEMI patients without using P-ECG were assigned to the conventional group (n=117; 33 females, mean age 70±13 years). There was no significant difference in door-to-reperfusion times between the rural and urban cases (70±32 vs. 69±29 min, P=0.73). Door-to-reperfusion times in the urban P-ECG group were shorter than those in the urban conventional group for weekday nighttime/holiday (65±21 vs. 83±32 min, P=0.0005). However, there was no significance different between groups for weekday daytime. First medical contact to reperfusion time (90±22 vs. 105±37 min, P=0.0091) in the urban P-ECG group were significantly shorter than in the urban conventional groups for weekday nighttime/holiday, but were not significantly different between the groups for weekday daytime. CONCLUSIONS: P-ECG is useful even in urban areas, especially for patients who develop STEMI during weekday nighttime or while on a holiday.

Predictors of outcome after catheter ablation for atrial fibrillation: Group analysis categorized by age and type of atrial fibrillation.

BACKGROUND: The outcome of catheter ablation could probably differ among patients with atrial fibrillation (AF), depending on age and AF type. We aimed to investigate the difference in predictors of outcome after catheter ablation for AF among the patient categories divided by age and AF type. METHODS AND RESULTS: A total of 396 patients with AF (mean age 65.69 ± 11.05 years, 111 women [28.0%]) who underwent catheter ablation from January 2018 to December 2019 were retrospectively analyzed. We divided the patients into four categories: patients with paroxysmal AF (PAF) or persistent AF (PeAF) who were 75 years or younger (≤75 years) or older than 75 years (>75 years). Kaplan-Meier survival analysis demonstrated that patients with PAF aged ≤75 years had the lowest AF recurrence among the four groups (log-rank test, p = .0103). In the patients with PAF aged ≤75 years (N = 186, 46.7%), significant factors associated with recurrence were female sex (p = .008) and diabetes (p = .042). In the patients with PeAF aged ≤75 years (N = 142, 35.9%), the only significant factor associated with no recurrence was medication with a renin-angiotensin system inhibitor (p = .044). In the patients with PAF aged >75 years (N = 53, 14.4%), diabetes was significantly associated with AF recurrence (p = .021). No significant parameters were found in the patients with PeAF aged >75 years (N = 15, 4.1%). CONCLUSIONS: Our findings indicate that the risk factors for AF recurrence after catheter ablation differed by age and AF type.

Catheter Ablation Energy Sources and Myocardial Injury and Coagulation Biomarkers During Uninterrupted Periprocedural Edoxaban Use　- A Subanalysis of KYU-RABLE.

BACKGROUND: The effects of catheter ablation (CA) energy sources on myocardial injury and coagulation biomarkers among Japanese non-valvular atrial fibrillation patients receiving uninterrupted periprocedural edoxaban are unclear. This KYU-RABLE exploratory subanalysis compared the effects of CA using radiofrequency energy vs. cryoballoon on: (1) myocardial injury; and (2) plasma edoxaban and coagulation biomarker concentrations measured before and after CA.Methods and Results:Plasma creatine kinase (CK), edoxaban, D-dimer, and prothrombin fragment 1+2 (F1+2) concentrations within 1 h before CA were compared with concentrations the day after. All biomarkers increased after CA, regardless of the energy source, but especially with cryoballoon. Significantly higher increases in CK concentrations from before to the day after CA were seen with cryoballoon compared with radiofrequency energy (P<0.0001). Edoxaban concentrations were similar in both groups. Concentrations of D-dimer and F1+2 increased in both groups, but were significantly higher in the cryoballoon group (P<0.0001 and P=0.006, respectively). There were no significant between-group differences in the incidence of thrombotic or bleeding events. CONCLUSIONS: Uninterrupted edoxaban concentrations were similar in both groups. Both myocardial injury and coagulation biomarkers increased after CA, especially with cryoballoon, but there was no difference in the incidence of thrombotic or bleeding events. These findings suggest the efficacy of uninterrupted edoxaban, regardless of the CA energy source. Periprocedural anticoagulation, particularly with cryoballoon, should be undertaken with care.

Prehospital 12-Lead Electrocardiography System in Oita Assisted Transport of "True" Acute Coronary Syndrome Patients to Optimal Institutes.

BACKGROUND: Mobile cloud electrocardiography (C-ECG) can reduce the door-to-balloon time of acute coronary syndrome (ACS) patients, so we hypothesized it would also assist in transporting ACS-suspected patients to the optimal institutes.Methods and Results: Initially, 10 fire departments in Oita had 10 ambulances equipped with C-ECG. Ambulance crews recorded a 12-lead ECG from the patient at the first point of contact and transmitted them to 18 hospitals (13 institutions (PCII) with 24-h availability for percutaneous coronary intervention (PCI) and 5 regional core hospitals (RCH) without 24-h PCI) for analysis by a cardiologist. During 41 months, 476 ECGs suspected to be ACS were transmitted and analyzed. Of these, 24 ECGs transmitted to PCII were judged as not requiring PCI, and the patients were directly transported to a RCH (PCII-RCH); 35 ECGs sent to a RCH were judged as requiring PCI, and the patients were directly transported to a PCII (RCH-PCII). The prevalence of cardiovascular disease was significantly higher in the RCH-PCII group than in the PCII-RCH group (P<0.01). There was no significant difference in the door-to-balloon time between the RCH-PCII and the group in which the C-ECG was sent to a PCII and the patients were transported directly to PCII (PCII-PCII) (49±14 vs. 59±20 min, P=0.14). CONCLUSIONS: Prehospital 12-lead ECG can assist in transporting ACS-suspect patients to the optimal treatment facility.

Reduction of bleeding complications on puncture site after percutaneous coronary intervention using a 6.5-French sheathless guiding catheter.

BACKGROUND: Reducing complications at the puncture site after percutaneous coronary intervention (PCI) is important. The diameter of a 6.5-French (Fr) sheathless guiding catheter (GC) is smaller by approximately 2-Fr compared to a 6-Fr conventional sheath. In the present study, we investigated the post-PCI puncture site complications of a transradial approach in each gender while using a 6.5-Fr sheathless GC. METHODS AND RESULTS: Our study consisted of 332 patients who underwent transradial coronary intervention (TRI) between August 2017 and July 2019. We classified the patients into either the 6.5-Fr sheathless GC (Asahi, Intecc, Aichi, Japan) Group (Sheathless group: n = 182 males, 58 females) or the 6-Fr sheathed GC Group (Sheathed group: n = 150 males, 36 females). We determined the complications at the puncture site: oozing, subcutaneous hemorrhage, formation of hematoma, pseudoaneurysms, and peripheral neuropathy. The body mass index of the patients was greater in the sheathless GC group compared to the sheathed GC group (24.5 ± 3.5 kg/m2 vs. 23.6 ± 3.7 kg/m2, p = 0.02). In males, there was no significant difference in the complication rate at the puncture site between the sheathless GC and sheathed GC groups (19.3% vs. 18.6%, p = 0.88). However, the complication rate at the puncture site in females was higher in the sheathed GC group than in the sheathless GC group (36% vs. 15.5%, p = 0.02). A multiple logistic regression analysis revealed that the use of a 6.5-Fr sheathless GC independently reduced the complications in female patients (p = 0.006). CONCLUSION: The use of the 6.5-Fr sheathless GC system in a transradial approach reduced the complications at the puncture site in female patients. The 6.5-Fr sheathless GC system may be a safe option for them compared to the conventional sheath system.

Fragmented QRS as a risk marker for the occurrence of ventricular fibrillation in patients with variant angina.

BACKGROUND: Variant angina (VA) is caused by reversible coronary artery spasm, which is characterized by chest pain with ST-segment elevations on standard 12-lead electrocardiogram (ECG) at rest. Ventricular fibrillation (VF) is often caused by VA attack, but the risk stratification is not well understood. The purpose of this study was to evaluate the impact of fragmented QRS (fQRS) on VF occurrence in VA patients. METHODS: Ninety-four patients who showed ST elevation on 12-lead ECGs with total or nearly total occlusion in response to coronary spasm provocation test were enrolled. Among them, 16 patients had documented VF before hospital admission (n = 12) or experienced VF during provocation test (n = 4) (VF occurrence group). The fQRS was defined as the presence of spikes within the QRS complex of two or more consecutive leads. RESULTS: The prevalence of fQRS was more often observed in the VF occurrence group than in the non-VF occurrence group (63% [10/16] vs. 27% [21/78], p = 0.009). Univariate analyses revealed that age, history of syncope, QTc, and the presence of fQRS were associated with VF occurrence (p = 0.004, 0.005, 0.029, and 0.008, respectively). Furthermore, upon multivariate analyses using those risk factors, age, QTc, and fQRS predicted VF occurrence independently (p = 0.007, 0.041, and 0.014, respectively). CONCLUSIONS: The present study demonstrated that fQRS in VA patients is a risk factor for VF. The fQRS may be a useful factor for the risk stratification of VF occurrence in VA patients.

Risk stratification in asymptomatic patients with Brugada syndrome: Utility of multiple risk factor combination rather than programmed electrical stimulation.

BACKGROUND: The prognostic value of programmed electrical stimulation (PES) in Brugada syndrome (BrS) remains controversial. Asymptomatic BrS patients generally have a better prognosis than those with symptoms. The purpose of this study was to evaluate the value of nonaggressive PES with up to two extra stimuli and predict clinical factors for risk stratification in asymptomatic BrS patients. METHODS: The study enrolled 193 consecutive asymptomatic BrS patients with type 1 ECG (mean age: 50 ± 13 years, 180 males) who underwent PES using a nonaggressive uniform protocol. Cardiac events (CEs: sudden cardiac death or ventricular tachyarrhythmia) during the follow-up period were examined. RESULTS: During a mean follow-up of 101 ± 48 months, seven asymptomatic patients (3.6%) had a CE. The incidence of CEs was not different between patients with and without inducible ventricular tachyarrhythmia by PES (p = .51). The clinical significance of risk factor combinations, including spontaneous type 1 ECG, family history of sudden cardiac death, QRS duration in lead V2 , and presence of J wave, was evaluated. Using the Kaplan-Meier method according to the number of risk factors, the prevalence of CE in patients with three or four risk factors was determined to be significantly higher than in those with one risk factor (p = .02 and p = .004, respectively). CONCLUSIONS: The present study suggests that inducibility of ventricular tachyarrhythmia does not predict future CEs in asymptomatic BrS patients. Combination analysis of the other four clinical risk parameters may be effective for risk assessment.

Usefulness of subcutaneous implantable cardioverter-defibrillator therapy in patients with Brugada syndrome.

Implantable cardioverter-defibrillators (ICDs) are the main therapy to prevent sudden cardiac death in patients with Brugada syndrome (BrS). The subcutaneous ICD (S-ICD) can eliminate lead-associated complications compared with transvenous ICD (TV-ICD). However, S-ICD is susceptible to T-wave oversensing (TWOS) and may result in more frequent inappropriate shocks in patients with BrS. This study aimed to compare inappropriate shocks between TV-ICD and S-ICD in patients with BrS. We enrolled 32 patients with BrS (including one woman; mean age 52 ± 18 years) who were implanted with ICD (23 TV-ICDs and 9 S-ICDs) between January 2002 and November 2018 in Oita University Hospital. We carried out a standard surface electrocardiogram (ECG) screening tests in both supine and standing positions prior to S-ICD implantation. The patients received routine clinical review every month and device monitoring every 4 months. The period of follow-up was 129 ± 51 months. Six patients with BrS and TV-ICDs experienced inappropriate shocks (26%) with their ICD therapy. In contrast, two patients with BrS and S-ICDs experienced inappropriate shocks (22%). There was no significant difference between the two groups (P = 0.82). Although one case in the S-ICD group experienced TWOS-induced inappropriate shock, SMART Pass (new high-pass filter) prevented the subsequent recurrence of inappropriate shocks during ICD therapy. Our results suggest that S-ICD is not inferior to TV-ICD in the incidence of inappropriate shocks. SMART Pass may be a useful tool to prevent inappropriate ICD shocks by TWOS in patients with BrS.

Long-term prognosis in patients with non-type 1 Brugada electrocardiogram: Results from a large Japanese cohort of idiopathic ventricular fibrillation.

BACKGROUND: Brugada syndrome (BrS) is diagnosed in patients with ST-segment elevation with spontaneous, drug-induced, or fever-induced type 1 morphology. Prognosis in type 2 or 3 Brugada electrocardiogram (Br-ECG) patients remains unknown. The purpose of this study is to evaluate long-term prognosis in non-type 1 Br-ECG patients in a large Japanese cohort of idiopathic ventricular fibrillation (The Japan Idiopathic Ventricular Fibrillation Study [J-IVFS]). METHODS: From 567 patients with Br-ECG in J-IVFS, a total of 28 consecutive non-type 1 patients who underwent programmed electrical stimulation (PES) (median age: 58 years, all male, previous sustained ventricular tachyarrhythmias [VTs] 1, syncope 11, asymptomatic 16) were enrolled. Cardiac events (CEs: sudden cardiac death or sustained VT/ventricular fibrillation) during the follow-up period were examined. RESULTS: During a median follow-up of 136 months, four patients (14%) had CEs. None of patients with PES- have experienced CEs. There was no statistically significant clinical risk factor for the development of CEs. Using the Kaplan-Meier method, the event-free rate significantly decreased in a group with all 3 risk factors (symptom, wide QRS complex in lead V2 , and positive PES) (p = .01). CONCLUSIONS: Our study revealed long-term prognosis in patients with non-type 1 Br-ECG. The combination analysis of these risk factors may be useful for the risk stratification of CEs in non-type 1 Br-ECG patients. The present study suggests that the patients with all these parameters showed high risk for CEs and need to be carefully followed.

Role of fragmented QRS and Shanghai score system in recurrence of ventricular fibrillation in patients with early repolarization syndrome.

BACKGROUND: The Shanghai Score System, which weighs electrocardiogram (ECG) findings reflecting repolarization abnormalities, has been proposed for diagnosis of early repolarization syndrome (ERS). However, recent studies have suggested the involvement of depolarization abnormalities in some ERS patients. The aim of this study was to validate the Shanghai Score System in predicting the recurrence of ventricular fibrillation (VF) in ERS patients. The predictive value of fragmented QRS (fQRS) was also investigated. METHODS: Fifteen consecutive ERS patients (14 males, median age of 47 years) with a history of VF were retrospectively reviewed. The Shanghai Score System points were calculated, and the presence of fQRS was evaluated. RESULTS: During the median follow-up period of 79.2 months, five patients experienced VF recurrence. In the VF recurrence group, two patients showed augmented amplitude of J waves with horizontal ST-segment, while the other three patients had dynamic changes in J-wave amplitude. The Shanghai Score System points in the VF recurrence group were higher than those in the VF non-recurrence group (6.5 [range: 5.8-6.8] vs. 4.5 [range: 4.0-4.5], p = 0.002). The presence of fQRS on standard 12-lead ECG was more frequently observed in the VF recurrence group compared with the non-recurrence group (100% vs. 10%, p = 0.002). CONCLUSIONS: The present study demonstrated that the Shanghai Score System could effectively identify ERS patients at high risk for VF recurrence. The results also suggested that the presence of fQRS, a marker of depolarization abnormalities, may be useful for predicting VF recurrence in ERS patients.

Catheter ablation of atrial fibrillation reduces heart failure rehospitalization in patients with heart failure with preserved ejection fraction.

BACKGROUND: Atrial fibrillation (AF) is associated with heart failure (HF) rehospitalization in patients with heart failure with preserved ejection fraction (HFpEF). OBJECTIVE: We tested the hypothesis that catheter ablation of AF could reduce HF rehospitalization compared with conventional pharmacotherapy in patients with HFpEF. METHODS: Eighty-five consecutive HFpEF (EF ≥ 50% and a history of HF hospitalization) patients diagnosed as AF by 12-lead electrocardiogram were retrospectively analyzed. Thirty-five patients who received catheter ablation (ABL group) were compared with 50 patients treated by antiarrhythmic drugs and/or beta-blockers (CNT group). The primary endpoint was rehospitalization due to HF. RESULTS: The patients characteristics did not differ between the two groups including, age (71 ± 8 vs 71 ± 13 years; P = .637), female sex (34% vs 36%; P = .870), mean plasma brain natriuretic peptide (145 ± 112 vs 195 ± 153 pg/mL; P = .111), mean left ventricular ejection fraction (62% ± 8% vs 61% ± 9%; P = .624), and type of AF (nonparoxysmal AF 60% vs 62%; P = .852). Amiodarone was continued 40% (14 out of 35) and 40% (20 out of 70) in ABL and CNT groups, respectively (P = 1.000). Neither major complication nor major side effect was observed during the follow-up period. During a mean follow-up period of 792 ± 485 days, Kaplan-Meier curve analysis showed that significantly more patients in the ABL group were free from HF rehospitalization (log-rank P = .0039). Additionally, multivariate analysis revealed that catheter ablation of AF was the only preventive factor of HF rehospitalization (OR = 0.15; 95% CI: 0.04-0.46; P < .001). CONCLUSIONS: Catheter ablation of AF reduced HF rehospitalization compared with conventional pharmacotherapy in patients with HFpEF in our institute. Multicenter randomized study is warranted to confirm the result.

Improved Risk Stratification of Patients With Brugada Syndrome by the New Japanese Circulation Society Guideline　- A Multicenter Validation Study.

BACKGROUND: The new guideline (NG) published by the Japanese Circulation Society (JCS) places emphasis on previous arrhythmic syncope and inducibility of ventricular fibrillation (VF) by ≤2 extrastimuli during programmed electrical stimulation (PES) for deciding the indication of an implantable cardioverter-defibrillator in patients with Brugada syndrome (BrS). This study evaluated the usefulness of the NG and compared it with the former guideline (FG) for risk stratification of patients with BrS.Methods and Results:This was a multicenter (7 Japanese hospitals) retrospective study involving 234 patients with BrS who underwent PES at baseline (226 males; mean age at diagnosis: 44.9±13.4 years). At diagnosis, 46 patients (20%) had previous VF, 100 patients (43%) had previous syncope, and 88 patients (37%) were asymptomatic. We evaluated the difference in the incidence of VF in each indication according to the new and FGs. During the follow-up period (mean: 6.9±5.2 years), the incidence of VF was higher in patients with Class IIa indication according to the NG (NG: 16/45 patients [35.6%] vs. FG: 16/104 patients [15.4%]), while the incidence of VF in patients with other than class I or IIa indication was similarly low in both guidelines (NG: 2/143 patients [1.4%] vs. FG: 2/84 patients [2.4%]). CONCLUSIONS: This study validated the usefulness of the NG for risk stratification of BrS patients.

Questionnaire in patients with aborted sudden cardiac death due to coronary spasm in Japan.

OBJECTIVES: We investigated the medical or mechanical therapy, and the present knowledge of Japanese cardiologists about aborted sudden cardiac death (ASCD) due to coronary spasm. METHODS: A questionnaire was developed regarding the number of cases of ASCD, implantable cardioverter-defibrillator (ICD), and medical therapy in ASCD patients due to coronary spasm. The questionnaire was sent to the Japanese general institutions at random in 204 cardiology hospitals. RESULTS: The completed surveys were returned from 34 hospitals, giving a response rate of 16.7%. All SCD during the 5 years was observed in 5726 patients. SCD possibly due to coronary spasm was found in 808 patients (14.0%) and ASCD due to coronary spasm was observed in 169 patients (20.9%). In 169 patients with ASCD due to coronary spasm, one or two coronary vasodilators was administered in two-thirds of patients [113 patients (66.9%)], while more than 3 coronary vasodilators were found in 56 patients (33.1%). ICD was implanted in 117 patients with ASCD due to coronary spasm among these periods including 35 cases with subcutaneous ICD. Majority of cause of ASCD was ventricular fibrillation, whereas pulseless electrical activity was observed in 18 patients and complete atrioventricular block was recognized in 7 patients. Mean coronary vasodilator number in ASCD patients with ICD was significantly lower than that in those without ICD (2.1 ± 0.9 vs. 2.6 ± 1.0, p < 0.001). Although 16 institutions thought that the spasm provocation tests under the medications had some clinical usefulness of suppressing the next fatal arrhythmias, spasm provocation tests under the medication were performed in just 4 institutions. CONCLUSIONS: In the real world, there was no fundamental strategy for patients with ASCD due to coronary spasm. Each institution has each strategy for these patients. Cardiologists should have the same strategy and the same knowledge about ASCD patients due to coronary spasm in the future.

Potential Risk of Hypoglycemia in Patients with Heart Failure.

The properties of glucose changes in patients with chronic heart failure remain elusive. In the present study, we investigated the sequential changes of interstitial glucose concentrations in patients with chronic heart failure and heart disease who were not undergoing antidiabetic therapy.A glucose monitoring device (FreeStyle Libre Pro) was attached to the backside of an upper arm and the interstitial glucose concentration was monitored every 15 minutes for 1 week. Eleven patients with chronic heart failure (Heart failure (+) ) and 7 patients with chronic heart diseases but not with heart failure (Heart failure (-) ) were enrolled. The average level and peak value of interstitial glucose concentrations, and the duration of hyperglycemia (≥ 140 mg/dL) were not significantly different between Heart failure (+) and Heart failure (-). The duration of hypoglycemia (< 80 mg/dL) was significantly longer and the trough value was significantly lower in Heart failure (+) compared with Heart failure (-). Most of the patients in Heart failure (+) were exposed to a long duration of hypoglycemia from midnight to morning. Importantly, none of the patients who showed hypoglycemia complained of any subjective symptoms during hypoglycemia. Malabsorption may be one of the mechanisms of hypoglycemia.In summary, patients with chronic heart failure are at risk of developing hypoglycemia even if they do not undergo any antidiabetic therapy.

Assessment of coronary flow reserve predicts long-term outcome of responders to cardiac resynchronization therapy.

Cardiac resynchronization therapy (CRT) has been established as a treatment for patients with chronic heart failure (HF). We tested the hypothesis that assessment of coronary flow reserve (CFR) predicts the long-term outcome of CRT. The study consisted of 114 HF patients implanted with a CRT device for the treatment of advanced HF between April 2010 and April 2018. After excluding patients that withdrew from long-term follow-up and patients missing a baseline CFR measurement, we enrolled 53 eligible patients. CFR was determined non-invasively by transthoracic echocardiography. Based on the ROC curve for predicting the appearance of major adverse cerebral and cardiovascular events (MACCE), the level of preserved CFR was set at >1.35 in responders. Accurate follow-up information (mean 873 ± 498 days) was obtained in 23 patients with a preserved CFR (16 females; mean age 71 ± 7.9 years) and 11 patients with a depressed CFR (5 females; mean age, 73 ± 7.6 years) in responders. Kaplan-Meier survival analysis demonstrated that the depressed CFR group had a higher prevalence of MACCE than the preserved CFR group (log rank, 9.83; p = 0.0021). Multivariate analysis revealed that depressed CFR was associated with MACCE (hazard ratio 4.88, 95% confidence interval 1.13-26.5, p = 0.0329). Our results suggest that the assessment of CFR predicts the outcome in responders to CRT. Preservation of coronary circulation flow might underlie one of the mechanisms for a better response to CRT in responders.

Seasonal variations of weather conditions on acute myocardial infarction onset: Oita AMI Registry.

The onset of acute myocardial infarction (AMI) has been reportedly related to weather conditions. The aim of this study was to investigate the impact of weather conditions on AMI onset. Our study population consisted of 274 patients enrolled in the Oita AMI Registry who were admitted with AMI between June 2012 and May 2013. We divided the 365 days of the year into the four seasons: spring (March, April, May), summer (June, July, August), autumn (September, October, November), and winter (December, January, February). We classified each day as a day of onset of AMI (onset day) or a day of non-onset of AMI (non-onset day). Information on maximum temperature, minimum temperature, mean humidity, and mean atmospheric pressure was obtained from the Japan Meteorological Agency. In summer, the temperatures and intraday temperature differences were significantly lower on onset days than on non-onset days. Receiver operating characteristic analysis for predicting AMI onset in each season showed that the maximum temperature 2 days before AMI onset in summer had the largest area under the curve (AUC = 0.72, p = 0.0005). Our analysis demonstrated that there exist specific weather conditions that influence AMI onset in each season in Oita prefecture. AMI onset in summer was particularly associated with the maximum temperature 2 days before AMI onset.