Publications by authors named "Kenichiro Yamagata"
Background: Predicting the origin of premature ventricular contraction (PVC) from the preoperative electrocardiogram (ECG) is important for catheter ablation therapies. We propose an explainable method that localizes PVC origin based on the semantic segmentation result of a 12-lead ECG using a deep neural network, considering suitable diagnosis support for clinical application.
Methods: The deep learning-based semantic segmentation model was trained using 265 12-lead ECG recordings from 84 patients with frequent PVCs.
A 77-year-old female patient with multiple pacemaker leads experienced hypotension and syncope during right heart catheterization. Imaging studies revealed a stenotic inferior vena cava with superior vena cava obstruction and well-developed retrograde collateral vessels, suggesting that balloon obstruction of the sole venous return site caused low cardiac output leading to syncope.
View Article and Find Full Text PDFIatrogenic vertebral artery injury during catheter ablation treated using coil embolization.
Pacing Clin Electrophysiol
October 2024
The internal jugular vein (IJV) is occasionally used for blood access during catheter ablation. Additionally, accidental injury of the vertebral artery during an IJV puncture is a rare complication that can result in catastrophic events, such as death. However, vascular access complications cannot be completely prevented despite the introduction of ultrasound-guided punctures.
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- - 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.
Article Synopsis
- 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
- 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.*
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.
Article Synopsis
- - 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.
Article Synopsis
- The study investigates the presence of non-pulmonary vein foci in patients with atrial fibrillation (AF), focusing on the superior vena cava (SVC) as a common source.
- 331 patients with AF underwent imaging before radiofrequency catheter ablation and were categorized into those with SVC foci (SVC +) and without (SVC -).
- Results showed that the SVC + group had more pronounced SVC crescent signs and larger right atrial volumes, indicating these features could assist in determining effective ablation strategies.
Article Synopsis
- 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.
Background: MitraClip therapy has become an alternative therapy for primary and secondary mitral regurgitation (MR) in patients at high surgical risk. However, this procedure is associated with several complications.
Case Summary: The patient was a 93-year-old male with severe MR caused by prolapse of the mid-posterior mitral leaflet (P2) and atrial enlargement.
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.
Background: Catheter ablation (CA) has been reported to be an effective therapeutic option for ventricular arrhythmias, even in patients with a left-ventricular assist device (LVAD). However, the issues of right-to-left shunting due to iatrogenic atrial septal defect (iASD) associated with procedures for CA have not been well documented. We describe a rare case of refractory hypoxia associated with right-to-left shunting via iASD after CA through the transseptal approach in an LVAD patient.
View Article and Find Full Text PDFBackground: Recent studies using an implantable loop recorder (ILR) have reported on clinical predictors of pacemaker implantation in patients with unexplained syncope. However, atrial fibrillation (AF) was not included as a risk factor; this may be because the precise mechanism of AF (persistent or paroxysmal) has not been explicitly investigated. Thus, this study aimed to investigate the relationship between paroxysmal AF and cardiac syncope recurrence requiring pacemaker implantation in patients with an ILR owing to unexplained syncope.
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