Eiichi Watanabe

Recently, some clinicians have been diagnosing and treating arrhythmias on the basis of electrocardiogram (ECG) devices with low accuracy. In Europe and the US, several statements on the use of ECGs have already been published by related academic societies. In addition, with the relaxation of regulations on media advertising ambulatory/wearable ECG devices, the frequency of use of simple ECG devices by the general public will increase in the future. Therefore, this statement describes the functions and features of non-invasive ambulatory or wearable ECG devices that have been approved as medical devices in Japan (and that can record ECGs remotely), as well as points to note when using them; provides an overview of data storage and security for ambulatory/wearable ECG devices and implantable loop recorders (ILRs), as well as discussing differences between their use and the use of non-invasive ambulatory/wearable ECG devices; and provides classes of recommendation for the use of these devices and their evaluation for each arrhythmia type or condition. We describe lead-based ambulatory ECG devices (classical 24-h Holter ECG monitoring), handheld ECG devices, handheld-based ECG devices using a smartphone, wearable ECG devices (smartwatch and garment ECG devices), and patch ECG devices. In addition, we provide information on methods that are not based on the original ECG, such as photoplethysmography and oscillometric blood pressure measurement, and describe the limitations of their use. We hope that the publication of this statement will lead to the appropriate use of ambulatory/wearable ECG devices in Japan.

OBJECTIVE: This study highlights a case in which we performed a complex percutaneous coronary intervention on a 60-mm chronic total occlusion lesion with a remarkably low radiation dose by using the SPOT region of interest (SPOT ROI) function available on the Alphenix Evolve Edition X-ray system (Canon Medical Systems). KEY STEPS: Fluoroscopy was conducted exclusively using SPOT ROI from the start of guiding catheter engagement. The wire successfully traversed the chronic total occlusion lesion with SPOT ROI. Despite a fluoroscopy time of 71 min, the total radiation dose was kept at 990 mGy, remaining <1 Gy. POTENTIAL PITFALLS: The SPOT ROI function is only available on the Alphenix Evolve Edition X-ray system and cannot be used with other X-ray equipment. TAKE-HOME MESSAGE: This case suggests that SPOT ROI can be leveraged to safely reduce radiation during complex percutaneous coronary intervention.

Recently, some clinicians have been diagnosing and treating arrhythmias on the basis of electrocardiogram (ECG) devices with low accuracy. In Europe and the US, several statements on the use of ECGs have already been published by related academic societies. In addition, with the relaxation of regulations on media advertising ambulatory/wearable ECG devices, the frequency of use of simple ECG devices by the general public will increase in the future. Therefore, this statement describes the functions and features of non-invasive ambulatory or wearable ECG devices that have been approved as medical devices in Japan (and that can record ECGs remotely), as well as points to note when using them; provides an overview of data storage and security for ambulatory/wearable ECG devices and implantable loop recorders (ILRs), as well as discussing differences between their use and the use of non-invasive ambulatory/wearable ECG devices; and provides classes of recommendation for the use of these devices and their evaluation for each arrhythmia type or condition. We describe lead-based ambulatory ECG devices (classical 24-h Holter ECG monitoring), handheld ECG devices, handheld-based ECG devices using a smartphone, wearable ECG devices (smartwatch and garment ECG devices), and patch ECG devices. In addition, we provide information on methods that are not based on the original ECG, such as photoplethysmography and oscillometric blood pressure measurement, and describe the limitations of their use. We hope that the publication of this statement will lead to the appropriate use of ambulatory/wearable ECG devices in Japan.

Acute heart failure is an important cause of unplanned hospitalizations and poses a significant burden through increased mortality and frequent hospitalizations. Heart failure with preserved ejection fraction (HFpEF) presents as a diverse condition characterized by complex cardiovascular and non-cardiovascular pathology. This study aimed to identify distinct clinical phenotypes in acute decompensated HFpEF (ADHF) using cluster analysis and assess their prognostic significance. We applied a latent class analysis to 1,281 ADHF patients admitted to a single cardiac intensive care unit between 2008 and 2022 with a left ventricular ejection fraction ≥ 50%. We used 83 factors obtained at hospitalization. We evaluated the association between phenogroups and clinical outcomes using either Cox regression model or Fine-Gray competing risk model. We identified 4 phenogroups: Phenogroup 1 (n = 133, 10%) included younger patients with metabolic disorders and a low level of B-type natriuretic peptide (BNP); Phenogroup 2 (n = 346, 27%) had systemic congestion and high BNP levels; Phenogroup 3 (n = 514, 40%) had multiple comorbidities and vascular disorders; Phenogroup 4 (n = 288, 22%) included older patients with bradyarrhythmia and atrial fibrillation. After adjusting for age, sex, and Get with the Guidelines-Heart Failure risk score, Phenogroup 2 had the highest risk of all-cause death and cardiac death. In conclusion, we identified 4 clinically relevant phenogroups of ADHF patients, each associated with different adverse outcomes. Phenotyping may provide a better understanding of the underlying mechanisms involved in the heterogeneity of ADHF and decompensation. Furthermore, it may facilitate the search for phenotype-specific therapeutic strategies.

INTRODUCTION: Coronary artery and heart valve calcification is a risk factor for cardiovascular death in haemodialysis patients, so calcification prevention should be started as early as possible. Treatment with concomitant calcimimetics and low-dose vitamin D receptor activators (VDRAs) is available, but not enough evidence has been obtained on the efficacy of this regimen, particularly in patients with short dialysis duration. Therefore, this study will evaluate the efficacy and safety of early intervention with upacicalcet, a calcimimetic used to prevent coronary artery calcification in this patient population. METHODS AND ANALYSIS: This multicentre, open-label, randomised, parallel-group controlled study will compare an early intervention group, which received upacicalcet and a low-dose VDRA, with a conventional therapy group, which received a VDRA. The primary endpoint is a change in log coronary artery calcium volume score from baseline to 52 weeks. The main inclusion criteria are as follows: (1) age 18 years or older; (2) dialysis is planned or dialysis duration is less than 60 months; (3) intact parathyroid hormone (PTH) >240 pg/mL or whole PTH level>140 pg/mL; (4) serum-corrected calcium≥8.4 mg/dL and (5) Agatston score >30. The main exclusion criteria are as follows: (1) history of parathyroid intervention or fracture in the past 12 weeks; (2) history of myocardial infarction, stroke or leg amputation in the past 12 weeks; (3) history of coronary angioplasty and (4) heart failure of New York Heart Association class III or worse. ETHICS AND DISSEMINATION: The study will comply with the Declaration of Helsinki and the Japanese Clinical Trials Act. The study protocol has been approved by the Fujita Health University Certified Review Board (file no. CR22-052). Written informed consent will be obtained from all participants. Study results will be presented in academic meetings and peer-reviewed academic journals. TRIAL REGISTRATION NUMBER: jRCTs041220126.

BACKGROUND: Circulating microRNAs (miRNAs, miR) have been considered as biomarkers reflecting the underlying pathophysiology in atrial fibrillation (AF). Nevertheless, miRNA expression in the peripheral blood samples might not reflect a cardiac phenomenon since most miRNAs are expressed in numerous organs. This study aimed to identify the cardiac-specific circulating miRNAs as biomarkers for AF. METHODS: Plasma samples were obtained from a luminal coronary sinus catheter (CS, cardiac-specific samples) and femoral venous sheath (FV, peripheral samples) in patients with AF and paroxysmal supraventricular tachycardia (control, CTL) undergoing catheter ablation. The circulating miRNA profiles were analyzed by small RNA sequencing. Differently expressed miRNAs between AF and CTL were identified in each sample of the CS and FV; miRNAs exhibiting similar expression patterns in the CS and FV samples were selected as candidates for cardiac-specific biomarkers. The selected miRNAs were related to the outcome of catheter ablation of AF. RESULTS: Small RNA sequencing detected 849 miRNAs. Among the top 30 most differently expressed miRNAs between AF and CTL, circulating hsa-miR-20b-5p, hsa-miR-330-3p, and hsa-miR-204-5p had a similar pattern in the CS and FV samples. Another set of peripheral blood samples was obtained from AF patients undergoing catheter ablation (n = 141). The expression of the miR-20b-5p and miR-330-3p, but not the miR-204-5p, negatively correlated with the echocardiographic left-atrial dimension and was decreased in patients with AF recurrence as compared to those without AF recurrence during a 1-year follow-up. CONCLUSION: Circulating miR-20b-5p and miR-330-3p can be cardiac-specific biomarkers for atrial remodeling progression and arrhythmia recurrence after catheter ablation in AF patients.

Abstract Persistent atrial fibrillation (PeAF) may develop arrhythmogenic substrates of rotors/multiple wavelets. However, the ways in which pulmonary vein isolation (PVI) affects the dynamics of rotor/multiple wavelets in PeAF patients remain elusive. Real-time phase-mapping (ExTRa mapping, EXT) in the whole left atrium (LA) was performed during PeAF before and after PVI (n = 111). The percentage of time in which rotor/multiple wavelets (phase singularities) was observed during each 5-s phase-mapping recording (non-passive activation ratio, %NP) was measured as an index of its burden. The mapping areas showing %NP ≥ 50% were defined as rotor/multiple-wavelet substrates (RSs). Before PVI, RSs were globally distributed in the LA. After PVI, %NP decreased (&lt; 50%) in many RSs (PVI-modifiable RSs) but remained high (≥ 50%) in some RSs, especially localized in the anterior/septum/inferior regions (PVI-unmodifiable RSs, 2.3 ± 1.0 areas/patient). Before PVI, vagal response (VR) to high-frequency stimulation was observed in 23% of RSs, especially localized in the inferior region. VR disappearance after PVI was more frequently observed in PVI-modifiable RSs (79%) than in PVI-unmodifiable RSs (55%, p &lt; 0.05), suggesting that PVI affects autonomic nerve activities and rotor/multiple wavelet dynamics. PVI-unmodifiable RSs were adjunctively ablated in 104 patients. The 1-year AT/AF-free survival rate was 70% in those with PVI alone (n = 115), and 86% in patients with the adjunctive ablation (log-rank test = 7.65, p &lt; 0.01). PVI suppresses not only ectopic firing but also rotor/multiple wavelets partly via modification of autonomic nerve activities. The adjunctive ablation of PVI-unmodifiable RSs improved the outcome in PeAF patients and might be a novel ablation strategy beyond PVI.

The early detection of acute myocardial infarction, which is caused by lifestyle-related risk factors, is essential because it can lead to chronic heart failure or sudden death. Echocardiography, among the most common methods used to detect acute myocardial infarction, is a noninvasive modality for the early diagnosis and assessment of abnormal wall motion. However, depending on disease range and severity, abnormal wall motion may be difficult to distinguish from normal myocardium. As abnormal wall motion can lead to fatal complications, high accuracy is required in its detection over time on echocardiography. This study aimed to develop an automatic detection method for acute myocardial infarction using convolutional neural networks (CNNs) and long short-term memory (LSTM) in echocardiography. The short-axis view (papillary muscle level) of one cardiac cycle and left ventricular long-axis view were input into VGG16, a CNN model, for feature extraction. Thereafter, LSTM was used to classify the cases as normal myocardium or acute myocardial infarction. The overall classification accuracy reached 85.1% for the left ventricular long-axis view and 83.2% for the short-axis view (papillary muscle level). These results suggest the usefulness of the proposed method for the detection of myocardial infarction using echocardiography.

BACKGROUND: Noninvasive electrocardiographic markers (NIEMs) are promising arrhythmic risk stratification tools for assessing the risk of sudden cardiac death. However, little is known about their utility in patients with chronic kidney disease (CKD) and organic heart disease. This study aimed to determine whether NIEMs can predict cardiac events in patients with CKD and structural heart disease (CKD-SHD). METHODS: We prospectively analyzed 183 CKD-SHD patients (median age, 69 years [interquartile range, 61-77 years]) who underwent 24-h ambulatory electrocardiographic monitoring and assessed the worst values for ambulatory-based late potentials (w-LPs), heart rate turbulence, and nonsustained ventricular tachycardia (NSVT). The primary endpoint was the occurrence of documented lethal ventricular tachyarrhythmias (ventricular fibrillation or sustained ventricular tachycardia) or cardiac death. The secondary endpoint was admission for cardiovascular causes. RESULTS: Thirteen patients reached the primary endpoint during a follow-up period of 24 ± 11 months. Cox univariate regression analysis showed that existence of w-LPs (hazard ratio [HR] = 6.04, 95% confidence interval [CI]: 1.4-22.3, p = .007) and NSVT [HR = 8.72, 95% CI: 2.8-26.5: p < .001] was significantly associated with the primary endpoint. Kaplan-Meier analysis demonstrated that the combination of w-LPs and NSVT resulted in a lower event-free survival rate than did other NIEMs (p < .0001). No NIEM was useful in predicting the secondary endpoint, although the left ventricular mass index was correlated with the secondary endpoint. CONCLUSION: The combination of w-LPs and NSVT was a significant risk factor for lethal ventricular tachyarrhythmias and cardiac death in CKD-SHD patients.

BACKGROUND: Atrial fibrillation (AF) is a heterogeneous condition caused by various underlying disorders and comorbidities. A cluster analysis is a statistical technique that attempts to group populations by shared traits. Applied to AF, it could be useful in classifying the variables and complex presentations of AF into phenotypes of coherent, more tractable subpopulations. OBJECTIVES: This study aimed to characterize the clinical phenotypes of AF using a national AF patient registry using a cluster analysis. METHODS: We used data of an observational cohort that included 7406 patients with non-valvular AF enrolled from 158 sites participating in a nationwide AF registry (J-RHYTHM). The endpoints analyzed were all-cause mortality, thromboembolisms, and major bleeding. RESULTS: The optimal number of clusters was found to be 4 based on 40 characteristics. They were those with (1) a younger age and low rate of comorbidities (n = 1876), (2) a high rate of hypertension (n = 4579), (3) high bleeding risk (n = 302), and (4) prior coronary artery disease and other atherosclerotic comorbidities (n = 649). The patients in the younger/low comorbidity cluster demonstrated the lowest risk for all 3 endpoints. The atherosclerotic comorbidity cluster had significantly higher adjusted risks of total mortality (odds ratio [OR], 3.70; 95% confidence interval [CI], 2.37-5.80) and major bleeding (OR, 5.19; 95% CI, 2.58-10.9) than the younger/low comorbidity cluster. CONCLUSIONS: A cluster analysis identified 4 distinct groups of non-valvular AF patients with different clinical characteristics and outcomes. Awareness of these groupings may lead to a differentiated patient management for AF.

It is important to objectively grasp the current status of automated electrocardiogram (ECG) diagnosis. This report aimed to analyze and evaluate ECG records that our members have encountered as an inappropriate diagnosis in real-world clinical practices.

The outbreak of coronavirus disease 19 (COVID-19) has had a great impact on medical care. During the COVID-19 pandemic, the rate of hospital admissions has been lower and the rate of in-hospital mortality has been higher in patients with acute coronary syndrome (ACS) in Western countries. However, in Japan, it is unknown whether the COVID-19 pandemic has affected the incidence of ACS. In the study, eleven hospitals in the Tokai region participated. Among enrolled hospital, we compared the incidence of ACS during the COVID-19 pandemic (April and May, 2020) with that in equivalent months in the preceding year as the control. During the study period; April and May 2020, 248 patients with ACS were admitted. Compared to April and May 2019, a decline of 8.1% [95% confidence interval (CI) 5.2-12.1; P = 0.33] in admissions for ACS was observed between April and May 2020. There was no significant difference in the strategy for revascularization and in-hospital deaths between 2019 and 2020. In conclusion, the rate of admission for ACS slightly decreased during the COVID-19 pandemic, compared to the same months in the preceding year. Moreover, degeneration of therapeutic procedures for ACS did not occur.

The prognostic role of D-dimer in different types of heart failure (HF) is poorly understood. We investigated the prognostic value of D-dimer on admission, both independently and in combination with the Get With The Guidelines-Heart Failure (GWTG-HF) risk score and N-terminal pro-B-type natriuretic peptide (NT-proBNP), in patients with preserved left ventricular ejection fraction (LVEF) and acute decompensated HF (HFpEF) or reduced LVEF (HFrEF). Baseline D-dimer levels were measured on admission in 1670 patients (mean age: 75 years) who were hospitalized for worsening HF. Of those patients, 586 (35%) were categorized as HFpEF (LVEF ≥ 50%) and 1084 as HFrEF (LVEF < 50%). During the 12-month follow-up period after admission, 360 patients died. Elevated levels (at least the highest tertile value) of D-dimer, GWTG-HF risk score, and NT-proBNP were all independently associated with mortality in all HFpEF and HFrEF patients (all p < 0.05). Adding D-dimer to a baseline model with a GWTG-HF risk score and NT-proBNP improved the net reclassification and integrated discrimination improvement for mortality greater than the baseline model alone in all populations (all p < 0.001). The number of elevations in D-dimer, GWTG-HF risk score, and NT-proBNP were independently associated with a higher risk of mortality in all study populations (HFpEF and HFrEF patients; all p < 0.001). The combination of D-dimer, which is independently predictive of mortality, with the GWTG-HF risk score and NT-proBNP could improve early prediction of 12-month mortality in patients with acute decompensated HF, regardless of the HF phenotype.

BACKGROUND: Blunted cyclic variation of heart rate (CVHR), measured as a decrease in CVHR amplitude (Acv), predicts mortality risk after acute myocardial infarction (AMI). However, Acv also can be reduced in mild sleep apnea with mild O2 desaturation. We investigated whether Acv's predictive power for post-AMI mortality could be improved by considering the effect of sleep apnea severity. METHODS: In 24-hr ECG in 265,291 participants of the Allostatic State Mapping by Ambulatory ECG Repository project, sleep apnea severity was estimated by the frequency of CVHR (Fcv) measured by an automated algorithm for auto-correlated wave detection by adaptive threshold (ACAT). The distribution of Acv on the Acv-Fcv relation map was modeled by percentile regression, and a function converting Acv into percentile value was developed. In the retrospective cohort of the Enhancing Recovery in Coronary Heart Disease (ENRICHD) study, consisting of 673 survivors and 44 non-survivors after AMI, the mortality predictive power of percentile Acv calculated by the function was compared with that of unadjusted Acv. RESULTS: Among the ALLSTAR ECG data, low Acv values appeared more likely when Fcv was low. The logistic regression analysis for mortality in the ENRICHD cohort showed c-statistics of 0.667 (SE, 0.041), 0.817 (0.035), and 0.843 (0.030) for Fcv, unadjusted Acv, and the percentile Acv, respectively. Compared with unadjusted Acv, the percentile Acv showed a significant net reclassification improvement of 0.90 (95% CI, 0.51-1.42). CONCLUSIONS: The predictive power of Acv for post-AMI mortality is improved by considering its relation to sleep apnea severity estimated by Fcv.

BACKGROUND: Functional capacity (FC) correlates with mortality in various cardiovascular diseases. The aim of this study was to examine whether cardiac pacemaker implantations improve the FC and affect the prognosis. METHODS AND RESULTS: We prospectively enrolled 621 de novo pacemaker recipients (age 76 ± 9 years, 50.7% male). The FC was assessed by metabolic equivalents (METs) during the implantation and periodically thereafter. The patients were a priori classified into poor FC (<2 METs, n = 40), moderate FC (2 ≤ METs < 4, n = 239), and good FC (≥4 METs, n = 342). Three months after the pacemaker implantation, poor FC or moderate FC patients improved to a good FC by 43%. The distribution of the three FCs remained at those levels until after 1 year of follow-up (P = .18). During a median follow-up of 2.4 years, 71 patients (11%) had cardiovascular hospitalizations and 35 (5.6%) all-cause death. A multivariate Cox analysis revealed that a poor FC at baseline was an independent predictor of both cardiovascular hospitalization (hazard ratio [HR] 2.494, P = .012) and all-cause death (HR 3.338, P = .016). One year after the pacemaker implantation, the eight who remained with a poor FC had a high mortality rate of 37.5% (P < .01). CONCLUSION: Approximately half of the poor or moderate FC patients improved to good FC 3 months after the pacemaker implantation. The baseline FC predicted the prognosis, and patients with an improved FC after the pacemaker implantation had a better prognosis.

AIM: We investigated the relationship between small dense low-density cholesterol (sdLDL-C) and risk of major adverse cardiovascular events (MACE) in patients treated with high- or low-dose statin therapy. METHODS: This was a prospective case-cohort study within the Randomized Evaluation of Aggressive or Moderate Lipid-Lowering Therapy with Pitavastatin in Coronary Artery Disease (REAL-CAD) study, a randomized trial of high- or low-dose (4 or 1 mg/d pitavastatin, respectively) statin therapy, in patients with stable coronary artery disease (CAD). Serum sdLDL-C was determined using an automated homogenous assay at baseline (randomization after a rule-in period, ＞1 month with 1 mg/d pitavastatin) and 6 months after randomization, in 497 MACE cases, and 1543 participants randomly selected from the REAL-CAD study population. RESULTS: High-dose pitavastatin reduced sdLDL-C by 20% than low-dose pitavastatin (p for interaction ＜0.001). Among patients receiving low-dose pitavastatin, baseline sdLDL-C demonstrated higher MACE risk independent of LDL-C (hazard ratio [95% confidence interval], 4th versus 1st quartile, 1.67 [1.04-2.68]; p for trend=0.034). High-dose (versus low-dose) pitavastatin reduced MACE risk by 46% in patients in the highest baseline sdLDL-C quartile (＞34.3 mg/dL; 0.54 [0.36-0.81]; p=0.003), but increased relative risk by 40% in patients with 1st quartile (≤ 19.5 mg/dL; 1.40 [0.94-2.09]; p=0.099) and did not alter risk in those in 2nd and 3rd quartiles (p for interaction=0.002). CONCLUSIONS: These findings associate sdLDL-C and cardiovascular risk, independent of LDL-C, in statin-treated CAD patients. Notably, high-dose statin therapy reduces this risk in those with the highest baseline sdLDL-C.

COVID-19 is a global catastrophe with markedly reduced health and economy of human civilization. Heart rhythm disorder has also been impacted by this disease. This statement is the universal criteria for EP procedures in the new era, which we will face during COVID-19 pandemic. We described the methods of triage based on the severity of disease, the regional state of pandemic and supply of medical resources. This guidance will be the universal criteria for EP procedures in the new era, which we will face during and after the COVID-19 pandemic.