Publications by authors named "Koji Miyamoto"
Identifying non-responders to cardiac resynchronization therapy in the non-left bundle branch block.
J Interv Card Electrophysiol
January 2025
Background: Non-response to cardiac resynchronization therapy (CRT) is an important issue in the treatment of heart failure with reduced ejection fraction (HFrEF) and non-left bundle branch block (LBBB). Electrocardiogram-gated myocardial perfusion single-photon emission computed tomography imaging (G-MPI SPECT) is typically used to assess left ventricular (LV) dyssynchrony. This study aimed to determine whether G-MPI parameters are associated with non-responsiveness to CRT.
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- The Japanese Catheter Ablation (J-AB) registry, launched in August 2017, is a nationwide voluntary study led by the Japanese Heart Rhythm Society focused on collecting data about catheter ablation procedures.
- In January 2022, the registry's data collection system shifted from REDCap to the Fountayn system to improve data management.
- By the end of 2022, the registry compiled data from 90,042 procedures across 614 hospitals, highlighting the types of arrhythmias, outcomes, and complications, with participants averaging 66.7 years old and 65.9% being male.
Article Synopsis
- Patients with improved left ventricular ejection fraction (LVEF >35%) after cardiac resynchronization therapy (CRT) have a lower risk of ventricular arrhythmia (VA) compared to those with low LVEF.
- The study involved 352 CRT patients, measuring serum B-type natriuretic peptide (BNP) levels after 6 months, showing that lower BNP levels correlate with a reduced risk of VA.
- High post-CRT BNP levels could indicate a greater risk of VA in patients who have improved LVEF, making BNP a useful predictor for VA risk in these patients.
Article Synopsis
- * The researchers explore enhancing efficiency by using measurement informatics, specifically Gaussian process regression (GPR) to optimize the collection of spin polarization data.
- * Their findings indicate that the GPR score can effectively be used as a stopping criterion, allowing for significant time savings of 5-10 times compared to traditional methods in conducting spin-resolved ARPES experiments.
Rice transcription factor DPF regulates stress-induced biosynthesis of diterpenoid phytoalexins.
Biosci Biotechnol Biochem
October 2024
Diterpenoid Phytoalexin Factor (DPF) is a key transcription factor involved in diterpenoid phytoalexin (DP) biosynthesis under non-stressed conditions in rice (Oryza sativa L.). Using clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9, DPF knockout rice lines were generated.
View Article and Find Full Text PDFBackground: The SMART Pass algorithm for subcutaneous implantable cardioverter-defibrillator prevents inappropriate shocks due to oversensing. The mechanisms and significance of SMART Pass deactivation remain unclear.
Objective: The objective of this study was to assess whether SMART Pass deactivation is associated with inappropriate shocks and to elucidate the underlying mechanism.
Article Synopsis
- An implantable loop recorder (ILR) is used to help diagnose unexplained syncope, especially in patients with inherited arrhythmia syndromes, like long-QT syndrome (LQTS), even though its effectiveness in detecting arrhythmias in LQTS is still debated.
- A case study of a 19-year-old female with LQTS type 1 showed that despite being on beta-blocker therapy, she continued to experience syncope without documented arrhythmias, leading to the decision to use the ILR for continuous monitoring.
- After two years, the ILR successfully recorded critical heart activity during a syncopal episode, revealing significant QT interval prolongation and T-wave alternance, thus emphasizing the potential of
Background: This study compared the stability of the Medtronic Attain Stability Quad (ASQ), a novel quadripolar active fixation left ventricular (LV) lead with a side helix, to that of conventional quadripolar leads with passive fixation (non-ASQ) and evaluated their LV lead performance.
Methods And Results: In all, 183 consecutive patients (69 ASQ, 114 non-ASQ) who underwent cardiac resynchronization therapy (CRT) between January 2018 and June 2021 were enrolled. Complications, including elevated pacing capture threshold (PCT) levels, phrenic nerve stimulation (PNS), and LV lead dislodgement, were analyzed during the postimplantation period until the first outpatient visit after discharge.
Article Synopsis
- The study investigates epicardial unipolar mapping in patients with Brugada syndrome (BrS) and compares it to patients with cardiomyopathy to identify unique characteristics.
- Findings reveal that patients with BrS have significantly higher J-wave amplitudes and a greater repolarization time dispersion index, which can be indicative of the syndrome with high sensitivity and specificity.
- The research highlights that the steep repolarization gradients observed in BrS patients may contribute to arrhythmias, suggesting a unique electrical profile that differentiates it from cardiomyopathy.
Background: The anatomical approach for the management of para-Hisian ventricular arrhythmias (VAs) with QRS morphological changes after catheter ablation (CA) has not been well investigated.
Objective: We aimed to evaluate the electrocardiographic and electrophysiological findings and ablation outcomes of para-Hisian VAs with QRS morphological changes after CA.
Methods: Of the 30 patients who underwent CA for para-Hisian VAs at 4 institutions, 10 (33%) had QRS morphological changes after ablation.
Article Synopsis
- The study investigates the impact of synchronized left ventricular pacing (sLVP) rates on clinical outcomes in patients undergoing adaptive cardiac resynchronization therapy (aCRT).
- In a cohort of 271 patients, it was found that those with higher sLVP rates (≥59.4%) had significantly better responses to treatment, showing a 71% CRT responder rate at 6 months.
- The results indicated that higher sLVP rates correlated with improved prognosis, reducing the risk of cardiac death and hospitalizations for heart failure, highlighting the importance of maintaining a sLVP rate above the identified threshold for better outcomes.
Article Synopsis
- An adaptive cardiac resynchronization therapy (aCRT) algorithm allows for continuous adjustment of pacing in patients with atrioventricular block and may be beneficial for those with pacemaker dependency, although its effectiveness was uncertain prior to this study.
- This study involved 64 patients with heart failure and pacemaker dependency, comparing those using the aCRT algorithm to those who were not, with the main focus on the risk of death or hospitalization for heart failure.
- Results showed that the aCRT algorithm significantly lowered the risk of adverse clinical outcomes in these patients, indicating it could be a key tool in their management.
Background: The prognosis and later fatal arrhythmia in cardiac sarcoidosis (CS) with relatively preserved cardiac function were unclear.
Objectives: This study aimed to evaluate the prognosis and arrhythmic events in patients with CS and mildly impaired cardiac function.
Methods: Data were collected from a nationwide Japanese cohort survey conducted in 57 hospitals (n = 420); 322 patients with CS with left ventricular ejection fraction (LVEF) >35% were investigated.
Article Synopsis
- - The study examined the link between the duration of atrial tachyarrhythmias (ATAs) and the risk of experiencing ventricular arrhythmias (VAs) in patients with cardiac resynchronization therapy defibrillators (CRT-D).
- - Researchers found that patients who had ATAs for longer than 24 hours in the first year post-CRT implantation had a significantly higher likelihood of developing VAs.
- - Specifically, the risk of both VAs and those relevant to ATAs increased with the duration of ATAs, with durations exceeding 6 minutes or 24 hours showing particularly high hazard ratios.
The Japanese Catheter Ablation (J-AB) registry, started in August 2017, is a voluntary, nationwide, multicenter, prospective, observational registry, performed by the Japanese Heart Rhythm Society (JHRS) in collaboration with the National Cerebral and Cardiovascular Center using a Research Electronic Data Capture system. The purpose of this registry is to collect the details of target arrhythmias, the ablation procedures, including the type of target arrhythmias, outcomes, and acute complications in the real-world settings. During the year of 2021, we have collected a total of 89 609 procedures (mean age of 66.
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- The study investigates the role of atrial natriuretic peptide (ANP) forms, particularly NT-proANP, in predicting cardiac outcomes for patients undergoing cardiac resynchronization therapy (CRT).
- Researchers conducted a study on 86 patients, measuring various ANP indicators before and after CRT, and found that NT-proANP was the only form significantly linked to worse clinical outcomes like cardiac death and hospitalizations.
- The findings suggest that higher pre-implantation NT-proANP levels can help predict which patients may face complications after receiving CRT, indicating its potential as a valuable biomarker.
Article Synopsis
- * In crops, variations in the genes for these enzymes may have arisen from duplication and adaptation for specialized functions, while the model plant Brachypodium distachyon has a simpler gene set related to gibberellin biosynthesis, including one ent-CPS gene and four KS-like genes.
- * Detailed studies revealed that BdCPS and BdKS1 in B. distachyon are crucial for gibberellin production, whereas BdKSL2 and BdKSL3 likely
Article Synopsis
- The study investigates the impact of ventricular arrhythmia (VA) on patients who received cardiac resynchronization therapy (CRT), focusing on its role as a prognostic marker.
- Among 330 CRT patients, those with VA events showed a higher risk of death or heart failure hospitalization, particularly those with fast VA.
- The findings indicate that VA is linked to worse CRT response and longer electrical conduction delays, suggesting it may indicate poor prognosis for CRT patients.
Article Synopsis
- Cardiac implantable electronic devices (CIEDs) can be affected by computed tomography (CT) irradiation, which has reported adverse events, but this procedure is still deemed safe.
- A study tested various CT protocols on a model with CIEDs, revealing instances of electrical activity disruptions, but no significant clinical issues like dangerous arrhythmias were confirmed.
- The findings suggest that CT irradiation generally poses minimal risk to patients with CIEDs, and routine adjustments to device settings before the procedure may not be needed for most cases.
Transvenous lead extraction versus surgical lead extraction or conservative treatment for cardiac implantable electronic device infections: Propensity score-weighted analyses of a nationwide claim-based database.
Pacing Clin Electrophysiol
August 2023
Article Synopsis
- Infection is a major complication in patients with cardiac implantable electronic devices (CIED), and this study analyzed treatments for CIED infections, focusing on transvenous lead extraction (TLE), surgical extraction, and conservative methods using data from over 3,600 patients.
- The analysis found that TLE was more common in younger patients and larger hospitals, increasing in frequency, while surgical extraction rates declined, showing TLE has associated benefits like lower in-hospital mortality and fewer readmissions.
- The study suggests TLE should be more frequently recommended as the primary treatment for CIED infections due to its better outcomes compared to surgical extraction and conservative treatment approaches.*