Publications by authors named "Akinori Wakamiya"
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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- 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.
Background: 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.
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- 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.
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- 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.
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- The study investigates how the placement of pacing leads in the right atrium affects the success of synchronized left ventricular pacing (sLVP) in adaptive cardiac resynchronization therapy (CRT).
- It evaluated 71 patients and found that those with leads in the right atrial septum had significantly higher sLVP rates (81%) compared to those with leads in the right atrial appendage (63%).
- Additionally, for patients with first-degree atrioventricular blocks, sLVP rates were generally higher in the septal group, indicating that right atrial septal pacing enhances sLVP effectiveness in CRT.
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.
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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.
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- 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.
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- 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.
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.*
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- High percent effective cardiac resynchronization therapy (CRT) pacing (%e-CRT) significantly affects clinical outcomes, particularly in heart failure patients.
- In a study involving 49 CRT patients with over 90% ventricular pacing, those with %e-CRT ≥ 97.4% experienced lower rates of heart failure hospitalization and higher responder rates compared to those with lower %e-CRT.
- The findings suggest that maximizing %e-CRT is beneficial for improving heart function and reducing hospitalizations related to heart failure.
Article Synopsis
- Implantable cardiac monitors (ICMs) are used to investigate unexplained fainting (syncope) and determine if patients might need a pacing device afterward.
- A study of 2,905 patients found that 16% required a pacing device, with older age, a history of atrial fibrillation, bundle branch block, and diabetes being key predictors.
- A risk scoring system was developed to help identify patients at different risk levels for needing a pacing device, emphasizing the importance of these predictors in early evaluations.
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- - The study investigated how interactive face-to-face (FTF) lectures about radiation exposure during atrial fibrillation ablation affect both operators and patients, compared to traditional passive lectures.
- - A total of 896 patients were analyzed, and results showed significant reductions in radiation exposure metrics (fluoroscopy time and air kerma) after implementing FTF lectures.
- - No significant differences in intraoperative complications were observed between the periods before and after the introduction of FTF lectures, indicating that the educational method is effective without compromising patient safety.
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- The study compares patient characteristics, clinical practices, and outcomes of cardiac implantable electronic device (CIED) therapy in Japan and the USA, using national administrative databases from both countries.
- It includes records from over 400,000 patients undergoing first-time CIED implantations and highlights differences in gender proportions, length of hospital stay, and certain outcome measures like in-hospital mortality and 30-day readmission rates.
- Results reveal that women make up a smaller percentage of defibrillator recipients in Japan, hospital stays are generally longer in Japan, and 30-day readmission rates are lower in Japan compared to the USA across all device types.
Article Synopsis
- - The Embo-Abl study aims to compare the rates of cerebral embolisms following catheter ablation (CA) for atrial fibrillation (AF) using cryoballoon (CB) versus radiofrequency (RF) techniques, as both are commonly used therapies with notable risks.
- - The study will involve 230 patients from various centers in Japan and will use MRI to detect clinically silent cerebral embolisms (SCEs) within 1-3 days post-ablation, with participants randomly assigned to either CB or RF groups.
- - This research is significant as it is the first of its kind to prospectively evaluate and compare the incidence of cerebral embolisms related to these two different ablation methods for AF. *
Article Synopsis
- The study investigates the impact of direct current (DC) cardioversion on maintaining sinus rhythm (SR) prior to catheter ablation (CA) in patients with persistent atrial fibrillation (PerAF).
- It involves 383 patients, divided into two groups based on whether they maintained SR for at least 24 hours post-cardioversion, showing a significant difference in AF recurrence rates between the groups after CA.
- The findings suggest that maintaining SR after DC cardioversion and the patient's age at first AF diagnosis are predictive of being free from AF following CA treatment.
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- A 48-year-old man with a genetic heart condition (ARVC) related to a gene mutation experienced severe heart failure and rapid heart rhythm issues, leading to hospitalization.
- During his stay, he suffered from sustained ventricular tachycardia that didn’t respond to typical antiarrhythmic treatments, requiring electrical cardioversion.
- He was diagnosed with a thyroid storm caused by Graves' disease and after receiving treatment for his hyperthyroidism, both his arrhythmia and heart failure symptoms improved, marking a unique case in medical literature.