rugada syndrome (BS) is characterized by ST-segment elevation in leads V1-3 with a right bundle branch block pattern and nocturnal sudden cardiac death caused by ventricular fibrillation (VF). 1,2 Patients with this syndrome who have experienced syncopal episodes or have been resuscitated from cardiac arrest have a poor prognosis if they do not receive an implantable cardioverter defibrillator (ICD). Although the prevalence of Brugada-type ECG change in healthy subjects is approximately 0.1-1%, their prognosis of is relatively good compared with symptomatic patients. 3-10 However, some asymptomatic patients become symptomatic and sudden cardiac death can occur with the first VF attack, so it is a problem in Japan of how to treat asymptomatic patients with a typical Brugada-type ECG who are detected by daily medical checkup. The results of some recent studies regarding the prognostic value of programmed electrical stimulation (PES) for patients with BS are conflicting; 6-9 Priori et al reported that the factors that predicted cardiac events were spontaneous ST elevation in leads V1-3 and episodes of syncope, but that VF inducible by PES did not indicate an increased risk of cardiac arrest, 7 whereas Brugada et al reported that induci-bility of ventricular arrhythmia and an abnormal ECG without provocation were predictors of arrhythmic events. 8,9 However, an electrophysiological study (EPS) is expensive and invasive, and sometimes results in complications, so it should not be carried out for all asymptomatic patients who show a Brugada-type ECG, but only for those patients for whom there is a high risk for a cardiac event. Because it is currently impossible to accurately predict the occurrence of cardiac events in asymptomatic patients, the present study was designed to determine noninvasive methods that could predict induction of VF by PES in asymptomatic patients with Brugada syndrome. For this purpose, the clinical characteristics of asymptomatic patients in whom VF was induced by PES were assessed, and the differences between the clinical values in asymptomatic patients with PES-induced VF and those without PES-induced VF were studied using noninvasive methods (a sodium channel blocker [pilsicainide] challenge test and a signal averaged electro-gram). Methods Patients The subjects of this study were 41 male asymptomatic patients with BS (age 27-66 years; mean age, 45±10 years). A Brugada-type ECG was defined as late r' wave (>0.2 mV) and ST segment elevation (>0.1 mV). 3 All of the subjects Circ J 2003; 67: 312-316 Ventricular fibrillation (VF) is induced in some asymptomatic patients with Brugada syndrome (BS), but the pro-gnostic value of programmed electrical stimulation (PES) in such patients is controversial. The clinical characteristics of 41 asymptomatic BS patients, divided into 2 groups according to whether VF was induced by PES (inducible VF group: n=13, non-inducible VF group: n=28) were evaluated. ST levels in the right precordial leads were measured before and after administration of pilsicainide...

BackgroundWe performed an exclusive study to investigate the associations between a total of 23 lactate-related indices during the first 24h in an intensive care unit (ICU) and in-hospital mortality. MethodsNine static and 14 dynamic lactate indices, including changes in lactate concentrations (Δ Lac) and slope (linear regression coefficient), were calculated from individual critically ill patient data extracted from the Multiparameter Intelligent Monitoring for Intensive Care (MIMIC) III database. ResultsData from a total of 781 ICU patients were extracted, consisted of 523 survivors and 258 non-survivors. The in-hospital mortality rate for this cohort was 33.0%. A multivariate logistic regression model identified maximal lactate concentration at 24h after ICU admission (max lactate at T24) as a significant predictor of in-hospital mortality (odds ratio = 1.431, 95% confidence interval [CI] = 1.278-1.604, p<0.001) after adjusting for predefined confounders (age, gender, sepsis, Elixhauser comorbidity score, mechanical ventilation, renal replacement therapy, vasopressors, ICU severity scores). Area under curve (AUC) for max lactate at T24 was larger (AUC = 0.776, 95% CI = 0.740-0.812) than other indices (p<0.001), comparable to an APACHE III score of 0.771. When combining max lactate at T24 with APACHE III, the AUC was increased to 0.815 (95% CI:0.783-0.847). The sensitivity, specificity, and positive and negative predictive values for the cut-off value of 3.05 mmol/L were 64.3%, 77.4%, 58.5%, and 81.5%, respectively.Kaplan-Myer survival curves of the max lactate at T24 for 90-day survival after admission to ICU demonstrated a significant difference according to the cut-off value (p<0.001). ConclusionsThese data indicate that the maximal arterial lactate concentration at T24 is a robust predictor of in-hospital mortality as well as 90-day survival in unselected ICU patients with predictive ability as comparable with APACHE III score.

The light-harvesting 1 reaction center (LH1-RC) complex from thermophilic photosynthetic bacterium Thermochromatium (Tch.) tepidum exhibits enhanced thermostability and an unusual LH1 Q transition, both induced by Ca binding. In this study, metal-binding sites and metal-protein interactions in the LH1-RC complexes from wild-type (B915) and biosynthetically Sr-substituted (B888) Tch. tepidum were investigated by isothermal titration calorimetry (ITC), atomic absorption (AA), and attenuated total reflection (ATR) Fourier transform infrared (FTIR) spectroscopies. The ITC measurements revealed stoichiometric ratios of approximately 1:1 for binding of Ca, Sr, or Ba to the LH1 αβ-subunit, indicating the presence of 16 binding sites in both B915 and B888. The AA analysis provided direct evidence for Ca and Sr binding to B915 and B888, respectively, in their purified states. Metal-binding experiments supported that Ca and Sr (or Ba) competitively associate with the binding sites in both species. The ATR-FTIR difference spectra upon Ca depletion and Sr substitution demonstrated that dissociation and binding of Ca are predominantly responsible for metal-dependent conformational changes of B915 and B888. The present results are largely compatible with the recent structural evidence that another binding site for Sr (or Ba) exists in the vicinity of the Ca-binding site, a part of which is shared in both metal-binding sites.

Energy spectrum analysis based on CWT as short as a 1.0-s VF ECG waveform enables prompt and reliable prediction of successful defibrillation.

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There are few reports about the incidence and predictors of silent cerebral thromboembolic lesions (SCLs) after atrial fibrillation (AF) ablation in patients treated with direct oral anticoagulants (DOACs). The purpose of this study is to evaluate the incidence and predictors of SCLs after AF ablation with cerebral magnetic resonance imaging (C-MRI) in patients treated with DOACs. We enrolled 117 consecutive patients who underwent first AF ablation and received DOACs, including apixaban, dabigatran, edoxaban, and rivaroxaban. DOACs were discontinued after administration 24 h before the procedure, and restarted 6 h after the procedure. During the procedure, activated clotting time (ACT) was measured every 15 min, and intravenous heparin infusion was performed to maintain ACT at 300-350 s. All patients underwent C-MRI the day after the procedure. SCLs were detected in 28 patients (24%) after AF ablation. Age, female sex, the presence of persistent AF, left atrial volume, procedure time, radiofrequency energy, electrical cardioversion, and mean ACT showed no correlations with the incidence of SCLs. Multivariate analysis revealed independent predictors of SCLs were CHADSVASc scores ≥3, left atrial appendage (LAA) emptying velocity ≤39 cm/s, and minimum ACT ≤260 s. Patients with both CHADSVASc scores ≥3 and LAA flow velocity ≤39 cm/s had the highest incidence of SCLs 15 of 26 patients (58%). In patients treated with DOACs, CHADSVASc score ≥3, minimum ACT ≤260 s, and LAA emptying velocity ≤39 cm/s were independent risk factors for the SCLs after AF ablation.

BACKGROUND: The assessment of gait function is important for stroke rehabilitation. Gait function of patients with stroke often depends on the type of orthosis. There are however few gait assessments that assess the type of orthosis. OBJECTIVE: The purpose of this study was to investigate the reliability and validity of our newly developed Ambulation Independence Measure (AIM), which assesses the gait function, type of orthoses and physical assistance, for acute stroke patients. METHODS: A total of 73 acute stroke patients participated in this prospective study. The AIM discriminates 7 levels of gait ability on the basis of the amount of physical assistance required and orthoses that are used during walking. Interrater reliability, concurrent validity with the Functional Ambulation Category (FAC) and predictive validity were examined. RESULTS: The weighted kappas of AIM at the start of gait training (baseline) and discharge were 0.990 and 0.978, respectively. The AIM scores were significantly correlated with the FAC scores at both baseline (r = 0.808) and discharge (r = 0.934). Multiple regression analyses showed that the AIM at baseline was a stronger predictor of the FAC at discharge (R2 = 0.80). CONCLUSIONS: The AIM has excellent reliability, concurrent validity, predictive validity, and good responsiveness in acute stroke patients.

Introduction: Recently, output-dependent QRS transition was reported to be required to confirm left bundle branch (LBB) capture in LBB area pacing (LBBAP) procedure. This study aimed to evaluate the achievement rate and the learning curve of LBB capture in LBBAP procedure performed with the goal of demonstrating output-dependent QRS transition, and investigate predictors of LBB capture. Methods and Results:The LBBAP procedure was performed in 126 patients with bradyarrhythmia. LBB capture was defined as a demonstration of output-dependent QRS transition. The following pacing definitions were used for evaluation: (1) LBBAP, which met the previously reported LBBAP criteria, (2) LBB pacing (LBBP), LBB capture was confirmed, and (3) available LBBP, LBB threshold was clinically usable (<3 V at 0.4 ms). The learning curve was evaluated by division into three timeperiods. The achievement rates of LBBAP, LBBP, and available LBBP were 88.1%, 41.2%, and 35.7%, respectively. The achievement rates of all three pacing definitions significantly increased with experience (p < .01), but the achievement rate of available LBBP was still 50% in the third period. As predictors of LBB capture, the interval between LBB-Purkinje potential and QRS onset ≥22 ms had high specificity of 98.3%, while R wave peak time in V6 < 68 ms had insufficient sensitivity of 79% and specificity of 68%. Conclusion:Even if LBB capture was aimed in LBBAP procedure, it was not easy to achieve, and there was a clear learning curve. Much of LBBAP may be left ventricular septal pacing that does not capture LBB.