Biomedical subjects

Takeshi Aiba

Publications and source records attributed to Takeshi Aiba.

2 recordsLinked to original sources

PubMed2026

Catecholaminergic polymorphic ventricular tachycardia mediated by ryanodine receptor 2: a validated risk stratification.

BACKGROUND AND AIMS: Patients with catecholaminergic polymorphic ventricular tachycardia (CPVT) are at risk for potentially life-threatening arrhythmic events (AEs) even while treated with β-blockers. The aim was to develop a model for individualized prediction of AEs in patients with RYR2-mediated CPVT on β-blocker monotherapy. METHODS: The derivation and independent validation cohorts included 743 and 129 patients, respectively. AEs were defined as arrhythmic syncope, appropriate implantable cardioverter-defibrillator shock, sudden cardiac arrest (SCA), and sudden cardiac death. Near-fatal or fatal AEs (nf/fAEs) included all AEs except for arrhythmic syncope. Prediction models using Cox regression were developed and internally and externally validated. RESULTS: A total of 102 (13.7%) patients in the derivation cohort and 24 (18.6%) patients in the validation cohort experienced ≥1 AE over a median follow-up of 5.1 [interquartile range (IQR), 7.7] and 2.4 (IQR, 4.4) years, respectively. Predictors of AE were arrhythmic syncope or SCA prior to diagnosis and age at β-blocker initiation. In the derivation and validation cohorts, the optimism-corrected C-indices of the models for AE were 0.67 [95% confidence interval (CI) 0.62-0.72] and 0.59 (95% CI 0.48-0.71), respectively. For nf/fAEs, ventricular arrhythmia severity before β-blocker initiation was a fourth independent predictor, and C-indices of the models in the derivation and validation cohorts were 0.74 (95% CI 0.68-0.80) and 0.60 (95% CI 0.47-0.72), respectively. In the derivation cohort, calibration slopes were 1.00 (95% CI 0.59-1.41) for AE and 1.00 (95% CI 0.69-1.32) for nf/fAE. CONCLUSIONS: These externally validated risk prediction models using clinical parameters accurately distinguished CPVT patients on β-blocker monotherapy at low and high risk for future AEs while treated with β-blockers. These models provide guidance for implementation of clinical management therapies to prevent AEs in patients with CPVT.

Humans↗

PubMed2026

Clinical Profile and Mode of Initiation of Spontaneous Ventricular Tachyarrhythmias in Patients With Brugada Syndrome (START-BrS).

BACKGROUND: Data on the spontaneous onset of ventricular tachyarrhythmias (VTAs) in Brugada syndrome (BrS), including polymorphic ventricular tachycardia (PVT) and monomorphic ventricular tachycardia (MVT), remain limited. OBJECTIVES: The goal of this study was to compare the clinical profile and mode of initiation of PVT and MVT in BrS. METHODS: This retrospective multicenter registry included 154 patients with BrS from 29 centers with documented VTA initiation captured by implantable cardioverter-defibrillator (94.9%) or electrocardiogram (5.1%). A total of 234 VTAs were analyzed, and initiation patterns were classified by using predefined electrocardiographic criteria. RESULTS: PVT was observed in 80.5% of patients, MVT in 16.9%, and both in 2.6%. Patients with MVT tended to be older, exhibit drug-induced Brugada electrocardiogram, and were more frequently White. Pause-dependent initiation occurred in approximately 25% of PVT and approximately 33% of MVT episodes. Coupling intervals initiating PVT were nonsignificantly shorter than for MVT (median 368 milliseconds vs 395 milliseconds), with a significantly lower prematurity index and faster early arrhythmia cycle length. Antecedent premature ventricular complexes were present in approximately 43% of both VTA types, commonly sharing morphology with the initiating premature ventricular complex. The prevalence of pathogenic/likely pathogenic SCN5A mutation did not differ between groups. CONCLUSIONS: In this largest analysis to date of spontaneous VTA onset in BrS, MVT occurred in a substantial minority and was associated with older age, White ethnicity, drug-induced electrocardiogram pattern, and a preceding tachycardia. Initiation patterns were broadly similar across arrhythmia types, although PVT exhibited a significantly lower prematurity index and faster early cycle length despite only nonsignificant shorter coupling intervals. These findings refine the clinical and electrophysiological characterization of BrS-related arrhythmias and delineate distinct features of PVT and MVT initiation.

Adult↗