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.

R-R' interval in the left bundle branch block predicts long-term outcomes after cardiac resynchronization therapy by estimating greater mechanical dyssynchrony and viable myocardium

BACKGROUND

Typical left bundle branch block (LBBB) shows 2 peaks of the R wave, which reflect activation reaching the interventricular septum (R) and posterolateral wall (R') sequentially.

OBJECTIVE

The purpose of this study was to investigate the relationship among R-R' interval (RR'), mechanical dyssynchrony, extent of viable myocardium, and long-term outcomes in cardiac resynchronization therapy (CRT) candidates.

METHODS

The study enrolled 49 patients (34 men; mean age: 69 ± 11 years) with LBBB who received CRT. The LBBB definition used requires the presence of mid-QRS notching in leads V1, V2, V5, V6, I, and aVL. Baseline evaluations were QRS duration (QRSd) and RR' measured from the 12-lead electrocardiogram; eyeball dyssynchrony (apical rocking and septal flash) and opposing-wall delay by speckle tracking from echocardiography, and extent of viable myocardium assessed by thallium-201 single-photon emission computed tomography. Primary outcomes included the combination of all-cause death and heart failure-related hospitalization.

RESULTS

RR' predicted volumetric response better than QRSd (area under the curve 0.73 vs 0.67, respectively). The long RR' group (≥48 ms) revealed more frequent eyeball dyssynchrony and significantly greater radial (SL) and circumferential dyssynchrony (AP and SL) and %viable segment than the short RR' group. In multivariate regression analysis, only RR' ≥48 ms was independently associated with higher event-free survival rates following CRT (hazard ratio 0.21; P = .014).

CONCLUSION

These findings suggest that RR' in complete LBBB was associated with mechanical dyssynchrony, extent of viable myocardium, and long-term outcomes following CRT.

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.

Impact of the COVID-19 Pandemic on the Long-Term Prognosis of Acute Myocardial Infarction in Japan

Background During the early phase of the coronavirus disease 2019 (COVID-19) pandemic, a global reduction in hospitalizations for acute myocardial infarction (AMI) was observed. Generally, patients experienced increased severity of AMI with delays in time from symptom onset to treatment during the pandemic. However, the impact of the COVID-19 pandemic on in-hospital mortality among patients with AMI remains unclear. This study aimed to compare the long-term prognosis of patients with AMI during the COVID-19 pandemic to that observed in the pre-pandemic period and to evaluate the influence of the COVID-19 pandemic on the prognosis of patients with AMI. Methods We reviewed the data of patients admitted to our hospital for AMI treatment between April 1, 2018, and March 31, 2021. The time from admission to major adverse cardiac events (MACE), as well as the time from admission to all-cause death, were examined between the pandemic period (April 1, 2020, to March 31, 2021) and the pre-pandemic period (April 1, 2018, to March 31, 2020). Results Eighty patients were included in the study, and those admitted during the pandemic exhibited a higher likelihood of advanced age, lower levels of LDL-cholesterol, and a reduced prevalence of hypertension. The 2.5-year MACE-free survival and overall survival rates between the patients during the pre-pandemic and pandemic periods were not significantly different. Conclusion The long-term prognosis of patients with AMI during the COVID-19 pandemic remains unclear. In this study, we reported that the 2.5-year MACE-free survival and overall survival rates of the patients with AMI admitted during the COVID-19 pandemic were not significantly different from those during the pre-pandemic period. The impact of the COVID-19 pandemic on the prognosis of patients with AMI appears to vary according to the study population.

Role of polyunsaturated fatty acids in Japanese patients with coronary spastic angina

BACKGROUND

n-3 polyunsaturated fatty acids (PUFAs) reduce the risk of ischemic heart disease. However, there are few reports of a relationship between n-3 PUFAs and coronary spastic angina (CSA). This study aimed to assess the age-dependent role of serum levels of fatty acid in patients with CSA.

METHODS AND RESULTS

We enrolled 406 patients who underwent ergonovine tolerance test (ETT) during coronary angiography for evaluation of CSA. All ETT-positive subjects were diagnosed as having CSA. We categorized the patients by age and results of ETT as follows: (1) young (age ≤ 65 years) CSA-positive (n = 32), (2) young CSA-negative (n = 134), (3) elderly (age > 66 years) CSA-positive (n = 36), and (4) elderly CSA-negative (n = 204) groups. We evaluated the serum levels of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), arachidonic acid, and dihomo-gamma-linolenic acid. In the young groups, the serum levels of EPA (64.3 ± 37.7 μg/mL vs. 49.4 ± 28.8 μg/mL, p = 0.015) and DHA (135.7 ± 47.6 μg/mL vs. 117.4 ± 37.6 μg/mL, p = 0.020) were significantly higher in the CSA-positive group than in the CSA-negative group, respectively. However, this was not the case with elderly groups. In the multivariate analysis in young groups, the serum levels of EPA (p = 0.028) and DHA (p = 0.049) were independently associated with the presence of CSA, respectively.

CONCLUSION

Our results suggested that the higher serum levels of EPA and/or DHA might be involved in the pathophysiology of CSA in the young population but not in the elderly population.

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.

Neutron resonance absorption imaging of simulated high-level radioactive waste in borosilicate glass

We performed a preliminary study of neutron resonance absorption imaging to investigate the spatial distribution of constituent elements in borosilicate glasses containing simulated high-level radioactive waste, in which elemental inhomogeneities affect the physical and chemical stabilities of the glass. Dips generated by the resonance absorptions of Rh, Pd, Na, Gd, Cs, and Sm were observed in the neutron transmission spectra of the glass samples. The spatial distributions of these elements were obtained from the neutron transmission images at the resonance energies. The distributions of Rh and Pd visualized the sedimentation of these platinum group elements. In contrast, the lanthanides (Gd and Sm) and Cs were uniformly dispersed. These results show that neutron resonance absorption imaging is a promising tool for characterizing borosilicate glasses and investigating the vitrification mechanism of high-level radioactive waste.

Association between interatrial septum adiposity and atrial fibrillation: transesophageal echocardiography imaging and autopsy study

Recent clinical evidence has suggested that interatrial septal (IAS) adiposity contributes to atrial fibrillation (AF). The present study aimed to confirm the usefulness of transesophageal echocardiography (TEE) to estimate IAS adiposity in patients with AF. The histological IAS analysis based on autopsy samples sought to clarify characteristics that underlie the contribution of IAS adiposity to AF. The imaging study analyzed the TEE results in patients with AF (n = 184) in comparison with transthoracic echocardiography (TTE) and computed tomography (CT) results. The autopsy study histologically analyzed IAS in subjects with (n = 5) and without (n = 5) history of AF. In the imaging study, the ratio of interatrial septum adipose tissue (IAS-AT) volume per epicardial adipose tissue (EpAT) volume was greater in patients with persistent AF compared (PerAF) to those with paroxysmal AF (PAF). Multivariable analysis revealed that both TEE-assessed IAS thickness and TTE-assessed left atrial dimension were predicted by CT-assessed IAS-AT volume. In the autopsy study, the histologically-assessed IAS section thickness was greater in the AF group than that in the non-AF group and was positively correlated with the IAS-AT area percentage. In addition, the size of adipocytes in IAS-AT was smaller, compared to EpAT and subcutaneous adipose tissue (SAT). IAS-AT infiltrated into the IAS myocardium, as if adipose tissue split the myocardium (designated as myocardial splitting by IAS-AT). The number of island-like myocardium pieces as a result of myocardial splitting by IAS-AT was greater in the AF group than in the non-AF group and was positively correlated with the IAS-AT area percentage. The present imaging study confirmed the usefulness of TEE to estimate IAS adiposity in patients with AF without radiation exposure. The autopsy study suggested that the myocardial splitting by IAS-AT may contribute to atrial cardiomyopathy leading to AF.

Multiple accessory pathways coexisting with a persistent left superior vena cava: a case report

BACKGROUND

Wolff-Parkinson-White syndrome is characterized by a short PR interval (delta-wave), long QRS complex, and the appearance of paroxysmal supraventricular tachycardia. Patients with Wolff-Parkinson-White syndrome usually have one accessory pathway, whereas cases with multiple accessory pathways are rare. Persistent left superior vena cava is a vascular anomaly in which the vein drains into the right atrium through the coronary sinus at the junction of the left internal jugular and subclavian veins due to abnormal development of the left cardinal vein. The simultaneous presence of multiple accessory pathways and persistent left superior vena cava has not been reported before.

CASE PRESENTATION

A 56-year-old Japanese man with a 5-year history of palpitations was referred for radiofrequency catheter ablation due to increased frequency of tachycardia episodes in the previous 2 months. Persistent left superior vena cava was confirmed by transthoracic echocardiography and computed tomography. An electrophysiological study revealed that the accessory pathways were located in the left lateral wall, anterolateral wall, and posteroseptal region. They were completely ablated with radiofrequency energy application.

CONCLUSIONS

We reported an extremely rare case of a patient with multiple accessory pathways and persistent left superior vena cava. Our case may suggest a potential embryological relationship between the multiple accessory pathways and persistent left superior vena cava.

Vagal response is involved in the occurrence of ventricular fibrillation in patients with early repolarization syndrome

BACKGROUND

Patients with early repolarization syndrome (ERS) and Brugada syndrome (BruS) have comparable clinical symptoms. In both conditions, ventricular fibrillation (VF) is experienced often near midnight or in the early morning hours when the parasympathetic tone is augmented. However, differences between ERS and BruS regarding the risk of VF occurrence have recently been reported. The role of vagal activity remains especially unclear.

OBJECTIVE

The goal of this study was to determine the relationship between VF occurrence and autonomic nervous activity in patients with ERS and BruS.

METHODS

We enrolled 50 patients with ERS (n = 16) and BruS (n = 34) who received an implantable cardioverter-defibrillator. Of these, 20 patients (5 ERS and 15 BruS) experienced VF recurrence (recurrent VF group). We investigated baroreflex sensitivity (BaReS) with the phenylephrine method and heart rate variability using Holter electrocardiography in all patients to estimate autonomic nervous function.

RESULTS

In both patients with ERS and BruS, there was no significant difference in heart rate variability between the recurrent VF and nonrecurrent VF groups. However, in patients with ERS, BaReS was significantly higher in the recurrent VF group than in the nonrecurrent VF group (P = .03); this difference was not evident in patients with BruS. High BaReS was independently associated with VF recurrence in patients with ERS according to Cox proportional hazards regression analyses (hazard ratio 1.52; 95% confidence interval 1.031-3.061; P = .032).

CONCLUSION

Our findings suggest that in patients with ERS, an exaggerated vagal response, as represented by increased BaReS indices, may be involved in the risk of VF occurrence.

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.

Interatrial conduction time is associated with left atrial low voltage area and predicts the recurrence after single atrial fibrillation ablation

Background

Interatrial conduction time (IACT) prolongs in fibrotic left atrium. We tested the hypothesis that IACT is related to left atrial low voltage area (LVA) and predicts the recurrence after single atrial fibrillation (AF) ablation.

Methods

One hundred sixty-four consecutive AF patients (79 non-paroxysmal) who underwent initial ablation in our institute were analyzed. IACT and LVA were defined as interval from the onset of P-wave to the basal left atrial appendage (P-LAA) activation, and area with bipolar electrogram < 0.5 mV covering over 5% of the total left atrial surface area during sinus rhythm, respectively. Pulmonary vein antrum isolation, non-PV foci ablation, and atrial tachycardia (AT) ablation were performed without substrate modification.

Results

LVA was frequently identified in patients with prolonged P-LAA ≥ 84 ms (n  = 28) compared with patients with P-LAA < 84 ms (n  = 136). Patients with P-LAA ≥ 84 ms were older (71 ± 10 vs. 65 ± 10 years, p  = .0061), and had more frequent non-paroxysmal AF (75% vs. 43%, p  = .0018), larger left atrial diameter (43.5 ± 4.5 vs. 39.3 ± 5.7 mm, p  = .0003), and higher E/e' ratio (14.4 ± 6.5 vs. 10.5 ± 3.7, p  < .0001) compared with P-LAA < 84 ms patients. After a mean follow-up period of 665 ± 153 days, Kaplan-Meier curve analysis showed that AF/AT recurrences was more frequently observed in patients with prolonged P-LAA (Log-rank p  = .0001). Additionally, univariate analysis revealed that P-LAA prolongation (OR = 1.055 per 1 ms, 95% CI: 1.028-1.087, p  < .0001) and the existence of LVA (OR = 5.000, 95% CI: 1.653-14.485 p  = .0053) were predictors of AF/AT recurrences after single AF ablation.

Conclusions

Our results suggested that prolonged IACT as measured by P-LAA was associated with LVA and predicts AT/AF recurrence after single AF ablation.

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.

Adolescent Persistent Atrial Fibrillation Concomitant with Pectus Excavatum

A 19-year-old man with pectus excavatum developed symptomatic persistent atrial fibrillation (AF). He had no remarkable medical history or comorbidities and had not exercised intensely during childhood. Electrical cardioversion and pre-treatment with amiodarone for two months failed to maintain sinus rhythm. Computed tomography before ablation revealed compression of the right and left atria between the sternal bone and vertebral bodies. Voltage mapping revealed that the right and left atrial voltages were preserved within the normal limit. However, radiofrequency catheter ablation successfully eliminated recurrent persistent AF. No recurrence was observed during eight months of follow-up.

Role of computed tomography-based evaluation of skeletal muscle area in predicting cardiovascular outcomes in patients with chronic heart failure after cardiac resynchronization therapy

AIM

This study aimed to determine possible associations between sarcopenia and poor cardiovascular outcomes in patients with chronic heart failure after cardiac resynchronization therapy.

METHODS

This retrospective study evaluated 120 patients who underwent cardiac resynchronization therapy between March 2004 and June 2018. In total, 58 patients who underwent computed tomography within 30 days of cardiac resynchronization therapy implantation were eligible for inclusion, and their data were analyzed (25 women; 33 men; mean age 71.6 ± 8.7 years). Skeletal muscle area was measured at the third lumbar vertebra, and skeletal muscle index was calculated. Major adverse cardiovascular events included cardiovascular death, hospitalization due to heart failure, cerebral infarction, acute myocardial infarction and cardiac arrest.

RESULTS

During the follow-up period (mean 868 ± 617 days), major adverse cardiovascular events occurred in 22 of 58 patients (38%). The patients were allocated to two groups according to sex-based tertiles of skeletal muscle index. The lowest tertile was defined as the low skeletal muscle index group. Kaplan-Meier survival analysis showed that the low skeletal muscle index group had a higher incidence of major adverse cardiovascular events (log-rank 4.38; P = 0.036). Cox proportional hazards regression analysis also showed that low skeletal muscle index values were significantly associated with major adverse cardiovascular events (hazard ratio 3.08; 95% confidence interval 1.26-7.66, P = 0.014).

CONCLUSIONS

Decreases in skeletal mass index on computed tomography might predict the occurrence of major adverse cardiovascular events in patients with chronic heart failure who underwent cardiac resynchronization therapy. Geriatr Gerontol Int 2022; ••: ••-••.

Arrhythmogenic right ventricular cardiomyopathy with plakophilin-2 genetic variant concomitant with early manifestation of ventricular tachyarrhythmia: A case series

Background

Arrhythmogenic right-ventricular cardiomyopathy (ARVC) is a hereditary cardiomyopathy characterized by fibro-fat replacement of the right-ventricular myocardium. There are many factors associated with poor prognosis in patients with ARVC. Among these factors, intensive physical exertion is considered an important risk factor for sudden cardiac death.

Case summary

Herein, we report a case series of siblings with ARVC and an early manifestation of ventricular tachyarrhythmia. Plakophilin-2 (PKP2) genetic variant, which is one of the causative genetic variants of ARVC, was detected by genetic testing in all three siblings. They were young athletes with lethal/symptomatic ventricular tachycardias. The eldest sibling was implanted with a transvenous implantable cardioverter defibrillator (ICD) due to resuscitated cardiopulmonary arrest at 18 years of age; the next oldest patient was treated with successful catheter ablation at 17 years; the youngest patient was treated with catheter ablation and subcutaneous ICD implantation at 17 years.

Discussion

A recent experimental model revealed that physical exertion in PKP2 knockout mice diminished cardiac muscle mass and increased cardiac myocyte apoptosis, despite enhanced arrhythmogenicity such as increased fractional shortening and calcium transient amplitude. The three siblings were heterozygous for the previously reported pathologic splice site variant c.2489 + 1G > A in Intron 12 of the PKP2. The variant might play an important role in facilitating the vulnerability to arrhythmia under intensive endurance training. Most ARVC patients with PKP2 variant, especially pathologic splice site variant c.2489 + 1G > A in Intron 12 of the PKP2, might have to be managed strictly regarding daily exercise.

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.

Atrial Fibrillation-triggered Ventricular Fibrillation in a Patient with Early Repolarization Syndrome

A 54-year-old man with early repolarization syndrome (ERS) implanted with an implantable cardioverter-defibrillator (ICD) developed persistent atrial fibrillation (AF) three years after the implantation. Similarly, the remote monitoring system begun frequently detecting ventricular fibrillation (VF) and polymorphic ventricular tachycardia (PVT). Longer RR intervals were repeatedly observed just before the initiation of PVT/VF. Catheter ablation for AF successfully diminished both the PVT and VF events.

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.

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.

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.

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.

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.

Distinctively different predictors for long-term outcomes between responders and nonresponders who underwent cardiac resynchronization therapy

BACKGROUND

It is common to develop heart failure (HF) events even in respondents to cardiac resynchronization therapy (CRT) during a long-term observation period. We investigated the predictors for long-term outcome in responders in comparison with nonresponders in patients diagnosed with HF along with implanted CRT.

METHODS

We enrolled 133 consecutive patients (mean age, 70 ± 10 years; 72 males) implanted with CRT from April 2010 to July 2019. Accurate follow-up information (mean follow-up period, 983 ± 801 days) was obtained from 66 responders and 53 nonresponders.

RESULTS

Kaplan-Meier event-free curves showed that major adverse cerebral and cardiovascular event (MACCE)-free ratio was significantly lower as the stage of renal function progresses (log rank, 19.5; P < .0001). The baseline estimated glomerular filtration rate (e-GFR) before CRT was not significantly different between nonresponders and responders. The e-GFR after judgment of CRT response was lower in patients with MACCEs than those without. Cox proportional hazards regression analysis revealed that low baseline e-GFR before CRT and after judgment of CRT response was closely related with MACCEs in responders, but not in nonresponders. The survival rate in responders without MACCEs assessed using Kaplan-Meier analysis was significantly larger in the preserved e-GFR (baseline value before CRT, >44 mL/min/1.73 m2) group than in the depressed group (log rank, 20.29; P < .0001).

CONCLUSION

We demonstrate that the factors for MACCEs during long follow-up periods were distinctively different between responders and nonresponders. Patients with depressed e-GFRs are suggested to have poor prognosis even if they are responders to CRT.

Changes in plasma concentrations of edoxaban and coagulation biomarkers according to thromboembolic risk and atrial fibrillation type in patients undergoing catheter ablation: Subanalysis of KYU-RABLE

BACKGROUND

Catheter ablation (CA) for atrial fibrillation (AF) can be associated with a risk of thromboembolism and bleeding. We recently demonstrated that uninterrupted edoxaban with one dose delayed on the CA procedural day is associated with a low risk of periprocedural complications. Previous reports have indicated that some specific subgroups of patients undergoing CA have an increased risk of bleeding and thromboembolic complications. This subanalysis of the KYU-RABLE study assessed the changes in plasma concentrations of edoxaban and coagulation biomarkers during the periprocedural period of CA in subgroups stratified by the risk of thromboembolism assessed by CHADS2 score (<2 or ≥2) and AF type (paroxysmal AF [PAF] or non-PAF).

METHODS

We evaluated changes in plasma concentrations of edoxaban and coagulation biomarkers (D-dimer and prothrombin fragment F1+2), by subgroup, during the periprocedural period of CA. Measurements were made prior to CA (procedure day).

RESULTS

This subanalysis evaluated data from 343 patients with CHADS2 score <2 and 134 patients with CHADS2 score ≥2, and from 280 patients with PAF and 197 patients with non-PAF. Plasma edoxaban concentration decreased with time on the day of CA, while plasma concentrations of coagulation biomarkers remained unchanged. No significant differences were observed according to CHADS2 score or type of AF.

CONCLUSIONS

The changes in plasma concentrations of edoxaban and coagulation biomarkers in each subgroup were similar to those of the whole analysis, regardless of the thromboembolic risk (CHADS2 <2 or ≥2) or AF type (PAF or non-PAF).

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.

Baroreflex Sensitivity in Patients With Atrial Fibrillation

Background

It has been reported that atrial fibrillation (AF) may contribute to impairment of baroreflex sensitivity (BRS). However, the difference of BRS between patients with persistent AF (PeAF) and those with paroxysmal AF (PAF) is unknown. We tested the hypothesis that patients with PeAF have a more impaired BRS compared with those with PAF.

Methods and Results

From October 2015 onwards, a total of 67 patients (14 women [20.9%]; mean age 65.2±10.1 years) with PAF (n=46, 68.7%) and PeAF (n=21, 31.3%), who underwent catheter ablation, were prospectively enrolled. The baseline BRS was evaluated during sinus rhythm. The baseline BRS in patients with PeAF was significantly lower than those with PAF (2.97 [0.52–6.62] ms/mm Hg versus 4.70 [2.36–8.37] ms/mm Hg, P=0.047). The BRS was significantly depressed after catheter ablation in all the patients (4.66 [1.80–7.37] ms/mm Hg versus 0.55 [−0.15 to 1.22] ms/mm Hg, P<0.001). However, the depression of BRS because of catheter ablation appeared attenuated in patients with PeAF when compared with those with PAF. The number of patients who did not show depression of BRS was significantly greater, that is, patients with PeAF (3/12, 25%) than those with PAF (0/46, 0%, P<0.01).

Conclusions

Our findings demonstrated that the baseline BRS was more depressed in patients with PeAF compared with PAF. Catheter ablation depressed BRS irrespective of the type of AF, with a greater effect in patients with PAF than PeAF.

Platelet volume indices correlate to severity of heart failure and have prognostic value for both cardiac and thrombotic events in patients with congenital heart disease

Introduction

Patients with heart failure are reported to have activated platelets leading to thrombotic events. Consequently, immature giant platelets are produced, and platelet distribution width (PDW) and mean platelet volume (MPV) increase. These platelet indices are easily, reasonably, and safely available by routine blood test and recently have been proposed as potential markers of cardiac events. However, little is known about the usefulness of platelet indices in patients with congenital heart disease (CHD).

Purpose

To test whether the hypothesis that PDW and MPV correlate to the severity of heart failure and have prognostic value in both future heart failure-related admission and thrombosis formation in patients with CHD.

Methods

We performed a retrospective, single-centre study that included 400 patients with CHD (median age, 34 years [range: 12–76]; 49% males; 35% single ventricular morphology), who were admitted in our institute between April 2014 and June 2017. We reviewed patients' medical records to assess their clinical information including medical history, blood sample data, and echocardiologic parameters. At first, we assessed the correlation between platelet indices and patients' clinical parameters. Next, we compared platelet indices before and after treatment for heart failure. Finally, using logistic regression and Kaplan-Meier analyses, we assessed prognostic factors of future heart failure-related admission and thrombosis formation.

Results

In multivariate analysis, a significant correlation was found between PDW and logBNP (brain natriuretic peptide) (p&lt;0.001), haemoglobin (p=0.01), D-dimer (p=0.019), Fontan operation (p&lt;0.001) and male sex (p&lt;0.001); as well as between MPV and logBNP (p&lt;0.001), D-dimer (p&lt;0.001) and Fontan operation (p=0.002). Throughout treatment of heart failure, significant reduction was found both in PDW (average value before treatment = 14.2, after treatment = 13.2, p=0.002) and MPV (before = 11.2, after = 10.8, p=0.004). In multivariate logistic regression analysis, predictors of future heart failure-related admissions were PDW (hazard ratio [HR]: 1.365; 95% confidence interval [CI]: 1.005–1.768), MPV (HR: 1.472; 95% CI: 1.055–2.052), age (HR: 1.063; 95% CI: 1.010–1.119), and SpO2 under 85% (HR: 5.089; 95% CI: 1.350–19.18). Using the same analysis, predictors of thrombotic formation were PDW (HR: 1.998; 95% CI: 1.461–2.630), MPV (HR: 1.792; 95% CI: 1.155–2.781), logBNP (HR: 1.196, 95% CI: 1.085–1.320), D-dimer (HR: 1.024; 95% CI: 1.007–1.042) and male sex (HR: 3.071; 95% CI: 1.079–8.737). In addition, during median follow-up of 28 months, the Kaplan-Meier analysis showed an improvement in both heart failure and thrombosis-free survival in the low PDW, as well as the low MPV group.

Conclusion

Platelet volume indices correlate to severity of heart failure and have prognostic value for both cardiac and thrombotic events in patients with congenital heart disease.

Funding Acknowledgement

Type of funding source: None

Long-term prognosis in patients with non-type 1 Brugada ECG: results from a large Japanese cohort of Brugada syndrome

Background

Most recent consensus conference report recommends Brugada syndrome (BrS) is diagnosed in patients with ST segment elevation with spontaneous, drug-induced or fever-induced type 1 morphology. Prognosis in patients with type 2 or 3 ECG without drug-induced or fever-induced type 1 ECG is still unknown.

Purpose

To evaluate a long-term prognosis in patients with non-type 1 Brugada ECG in a large Japanese cohort of BrS (The Japan Idiopathic Ventricular Fibrillation Study [J-IVFS]).

Methods

From 528 patients in J-IVFS, a total of 28 consecutive non-type 1 patients (54±14 years, all male, previous sustained ventricular tachyarrhythmias (VTs) 1, syncope 11, asymptomatic 16) were enrolled. Cardiac events (CI: sudden cardiac death or VTs) during the follow-up period were evaluated, and risk factors for the cardiac events were assessed.

Results

During a mean follow-up period of 111±91 months (median 134 months), 4 patients experienced cardiac events (1.5%/yr), who all had received implantable cardioverter defibrillator implantation. There was no statistically significant clinical risk factor for cardiac events. However, the incidences of cardiac events tended to be higher in symptomatic patients (CI: 25.0, non-CI: 6.3%, p=0.17), those with wide QRS duration &gt;90 msec in lead V2 (CI: 30.0, non-CI: 6.3%, p=0.11), and those with inducible VTs (CI: 21.1, non-CI: 0%, p=0.20), as determined by the Kaplan-Meier method. The annual incidences of cardiac events in patients with symptom, wide QRS duration &gt;90msec in lead V2, or inducible VTs were 2.8, 3.5, and 2.0%/yr, respectively. The incidences of cardiac events were significantly higher in patients with all these 3 factors (9.9%/yr) than those without (p=0.01).

Conclusions

Our large-scaled multicentre study revealed long-term prognosis in patients with non-type 1 Brugada ECG. The combination of symptom, wide QRS duration in lead V2, and inducible VTs may be useful to evaluate risk for cardiac events. The patients with all these parameters showed high risk for cardiac events and need to be carefully followed.

Funding Acknowledgement

Type of funding source: None

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.

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.

Impact of Age on Gender Differences in the Acute Myocardial Infarction Onset–Weather Association ― Oita AMI Registry ―

Background: The onset of acute myocardial infarction (AMI) is related to weather conditions, but the impact of age on gender differences in the AMI onset–weather association has not been elucidated.

Methods and Results: We analyzed the Oita AMI Registry and obtained data for 403 enrolled patients. To examine the impact of age, we categorized the patients into 4 groups: young (age ≤65 years) women (n=20); young men (n=123); elderly (age >65 years) women (n=84); and elderly men (n=176). The analyzed meteorological factors were maximum and minimum temperature, intraday temperature difference, average humidity, and average atmospheric pressure. The young women group had a higher minimum temperature (17.7±5.7℃ vs. 13.8±8.2℃, P=0.04), lower intraday temperature difference (7.0±2.6℃ vs. 8.4±2.9℃, P=0.03), higher average humidity (74.5±12.1% vs. 68.1±12.0%, P=0.03), and lower average atmospheric pressure (1,009.5±5.0 hPa vs. 1,012.9±5.8 hPa, P=0.01) than the young men group on the onset day. In the elderly groups, there was no significant difference in meteorological variables except for the intraday temperature difference 2 days before AMI onset.

Conclusions: AMI onset appears to be more sensitive to weather conditions (i.e., minimum temperature, average atmospheric pressure, and average humidity) in young patients than in elderly patients. In particular, young women had AMI on days with low intraday temperature difference and high humidity relative to men.

An experimental setup for creating and imaging 4He2 * excimer cluster tracers in superfluid helium-4 via neutron-3He absorption reaction

For the purpose of future visualization of the flow field in superfluid helium-4, clusters of the triplet state excimer ⁴He₂ ^* are generated along the micro-scale recoil tracks of the neutron-absorption reaction n + ³He → ³T + p. This reaction is induced by neutron irradiation of the ³He fraction contained in natural isotopic abundance liquid helium with neutron beams either from the Japan Proton Accelerator Research Complex, Materials and Life Science Experimental Facility (JPARC)/Materials and Life Science Experimental Facility or from the Kyoto University Institute for Integrated Radiation and Nuclear Science. These ⁴He₂ ^* clusters are expected to be ideal tracers of the normal-fluid component in superfluid helium with several advantageous properties. Evidence of the excimer generation is inferred by detection of laser induced fluorescence emitted from the ⁴He₂ ^* clusters excited by a purpose-built short pulse gain-switched titanium:sapphire (Ti:sa) laser operating at a wavelength of 905 nm. The setup and performance characteristics of the laser system including the Ti:sa and two continuous wave re-pumping lasers are described. Detection at the fluorescence wavelength of 640 nm is performed by using optical bandpass filtered photomultiplier tubes (PMT). Electrical noise in the PMT acquisition traces could successfully be suppressed by post-processing with a simple algorithm. Despite other laser-related backgrounds, the excimer was clearly identified by its fluorescence decay characteristics. Production of the excimer was found to be proportional to the neutron flux, adjusted via insertion of different collimators into the neutron beam. These observations suggest that the apparatus we constructed does function in the expected manner and, therefore, has the potential for groundbreaking turbulence research with superfluid helium.

P5029Inducibility of ventricular tachyarrhythmias by up to two extrastimuli does not predict future cardiac events in asymptomatic Brugada patients: results from long-term follow-up

Background

Most recent consensus conference report recommends Implantable Cardioverter Defibrillator (ICD) implantation for asymptomatic Brugada patients with spontaneous or fever-induced type-1 ECG (A-BrS) and inducible ventricular tachyarrhythmias (VTs) by up to two extrastimuli as class IIb indication. However, the validity of the inducible VTs by up to two extrastimuli in A-BrS is still unknown.

Purpose

To evaluate the validity of the inducibility by up to two extrastimuli in A-BrS in a large Japanese cohort of BrS (The Japan Idiopathic Ventricular Fibrillation Study [J-IVFS]).

Methods

A total of 193 consecutive A-BrS patients performed programmed electrical stimulation (PES) with non-aggressive uniform protocol (mean age 50±13 years, 180 males) were enrolled. PES protocol was using 2 basic pacing cycles and the order of introduction of up to 2 ventricular extra-stimuli from right ventricular apex [RVA] first, then right ventricular outflow tract [RVOT], 3 ventricular extra-stimuli from RVA then RVOT down to the minimum of 200ms. Clinical outcomes during the follow-up period were compared between A-BrS patients with and without inducible VTs by up to two extrastimuli.

Results

Thirty-five A-BrS (18%) had inducible VTs by up to two extrastimuli. During a mean follow-up period of 101±48 months, 7 A-BrS experienced cardiac events (sudden cardiac death [SCD] or VTs, 0.4%/yr). None of the 7 A-BrS had inducible VTs by up to two extrastimuli. The incidences of cardiac events tended to be higher in A-BrS without inducible VTs by up to two extrastimuli than in those with inducible VTs (p=0.10), as determined by the Kaplan-Meier method. In the A-BrS, the annual incidences of cardiac events in A-BrS with family history of SCD, inferolateral J wave, wide QRS duration >90msec in lead V2, or inducible VT/VF by 3 extrastimuli were 0.7, 0.7, 0.6, and 0.3%/yr, respectively.

Conclusions

Our large-scaled multicentre study with long-term follow-up revealed the inducibility of ventricular tachyarrhythmias by up to two extrastimuli does not predict future cardiac events in A-BrS, even using non-aggressive uniform protocol. Rather, other parameters such as family history of SCD or inferolateral J wave might be helpful for risk assessment in A-BrS.

4090Maximum standardized uptake value of pericardial fat for prediction of ventricular arrhythmias in patients with cardiac sarcoidosis

Background

Cardiac sarcoidosis is a cause of epicarditis and sustained life-threatening ventricular arrhythmias. These arrhythmias occasionally arise from epicardial. Positron emission tomogramphy-comututed tomography (PET-CT) is useful for diagnosis with sarcoidosis. However, the usefulness for prediction of ventricular arrhythmias in patients with cardiac sarcoidosis is unknown.

Objective

We hypothesized that the evaluation of pericardial fat inflammation could identify high-risk sarcoidosis patients for ventricular arrhythmias.

Methods

We enrolled 20 consecutive patients with cardiac sarcoidosis performed PET-CT between August 2016 and December 2018. In each case, we measured the maximum standardized uptake value (SUVmax) of pericardial fat around the left atrium, both ventricules, atrioventricular groove, and left main coronary.

Results

Seven patients experienced ventricular tachycardia (VT) or ventricular fibrillation (VF). VT/VF patients had significantly more complete right bundle branch block (P=0.035), larger left atrial dimension (P=0.021), larger left ventricular end-diastolic dimension (P=0.005), lower ejection fraction (P=0.007), and higher E/e' (P=0.004). SUVmax of pericardial fat in the roof of left atrium (LA) and left ventricular (LV) with VT/VF patients were significantly higher than non-VT/VF patients (LA: 1.63 vs 1.32, P=0.0311; LV: 1.84 vs 1.26, P=0.045). The cut-off values of SUVmax derived from the ROC curve in the roof of LA and LV are 1.47 and 1.59 respectively. The Kaplan Meire estimator showed that high SUVmax patients in the roof of LA had significantly more detection of NSVT.

Conclusions

Our results suggest the relationship between SUVmax and VT/VF occurrence in patients with cardiac sarcoidosis. The evaluateon of SUVmax may be useful for VT/VF risk stratification.

P1628Angiopoietin-like protein (Angptl) 2 secreted from epicardial adipose tissue induces atrial myocardial fibrosis

Background

Using excised human left atrial appendage samples, we previously demonstrated that epicardial adipose tissue (EAT) are highly associated with atrial myocardial fibrosis as a substrate of atrial fibrillation (AF). We also reported the relationship between Angptl2 in EAT and atrial fibrosis. However, the mechanism is not clear. The purpose is to clarify the mechanisms underlying the effect of EAT on the atrial myocardium.

Methods

Human peri-left atrial EAT and abdominal subcutaneous adipose tissue (SAT) samples were obtained from 6 cases (2 females, 70.2±13.2 years). 50 mg of EAT and SAT were quickly washed with PBS and centrifuged 1min at 1200rpm. After 3 times this procedures, adipose tissues were cultured in DMEM F12 medium with Fetal bovine Serum (FBS) overnight.

After pre-incubation, EAT and SAT tissues were washed and centrifuge d three times and cultured in medium without FBS for 24hours. Finally, we collected oozed medium (conditioned medium) and used for experiments.

Concentrations of Angptl2 in conditioned medium were measured by ELISA.

To study the effects of conditioned medium, we used “organo-culture” system. Isolated atrium from 8week old male Sprague-Dawley rats were placed on the porous membrane with the endothelial face toward the membrane. After that, loading medium (conditioned medium:culture medium = 1:4), culture medium (control), or recombinant Angptl2 were dropped onto the epicardial face of the atrium once a day and incubated for 7 days (37°C, 5% CO2).

Then, histological and immunohistochemical analysis were performed. We also performed quantitative reverse transcription–polymerase chain reaction (RT–PCR) analysis.

Next, we isolated and cultured neonatal rat fibroblast and loaded Angptl2 for 24 hours.After collected these cells, we performed western blotting analysis.

Results

Atria organo-culture incubated for 7 days with conditioned medium showed global fibrosis. At epicardial side, fibrotic area of EAT group was significantly greater compared to that of SAT and control group (P<0.05).

mRNA of Col1a1, col3a1 and TGFβ1 were significantly increased in EAT group compared with the SAT and control group.

And, the concentration of conditioned medium created from EAT was significant higher than that from SAT (P<0.05).

Then, we dropped 500 ng/ml of recombinant Angptl2 onto the rat atria. Fibrotic area of Angptl22 group significantly greater than that of control with increasing number of α-SMA positive cells, and mRNA of col3a1 and TGFβ1 were significantly increased in Angptl2 group compared with control group.

In cultured fibroblasts, α-SMA and p-ERK expression were increased in Angptl2 group measured by western blotting analysis.

Conclusions

Our results demonstrated that EAT rather than SAT induces atrial myocardial fibrosis. There is a possibility that Angptl2 effused from EAT plays a part in atrial fibrosis thought EAT paracrine effect.

Acknowledgement/Funding

ONO PHARMACEUTICAL CO