Global Thrombosis Test - a possible monitoring system for the effects and safety of dabigatran

© Otsui et al. 2015BACKGROUND: Dabigatran is an alternative to warfarin (WF) for the thromboprophylaxis of stroke in patients with non-valvular atrial fibrillation (NVAF). The advantage of dabigatran over WF is that monitoring is not required; however, a method to monitor the effect and the safety of dabigatran is not currently available. The Global Thrombosis Test (GTT) is a novel method to assess both clot formation and lysis activities under physiological conditions. OBJECTIVE: The aim of this study was to evaluate whether treatment with dabigatran might affect shear-induced thrombi (occlusion time [OT], sec) by the GTT, and to investigate the possibility that the GTT could be useful as a monitoring system for dabigatran. PATIENTS/METHODS: The study population consisted of 50 volunteers and 43 NVAF patients on WF therapy, who were subsequently switched to dabigatran. Using the GTT, the thrombotic status was assessed one day before and 1 month after switching anticoagulation from WF to dabigatran. RESULTS: The OT was 524.9 ± 17.0 sec in volunteers whereas that of NVAF patients on WF therapy was 581.7 ± 26.3 sec. The switch from WF to dabigatran significantly prolonged OT (784.5 ± 19.3 sec). One patient on WF therapy and 12 patients on dabigatran therapy were shown to have OT > 900 sec. CONCLUSION: The GTT could be used to assess the risk of dabigatran-related bleeding complications.Peer reviewe

Topographic variability of the left atrium and pulmonary veins assessed by 3D-CT predicts the recurrence of atrial fibrillation after catheter ablation

AbstractBackgroundCatheter ablation (CA) is an established therapy for atrial fibrillation (AF). However, the assessment of anatomical information and predictors of AF recurrence remain unclear. We investigated the relationship between anatomical information on the left atrium (LA) and pulmonary veins (PVs) from three-dimensional computed tomography images and the recurrence of AF after CA.MethodsSixty-seven consecutive AF patients (mean age: 62±10 years, median AF history: 42 (12; 60) months, mean LA size: 41±7mm, paroxysmal: 56%) underwent CA and were followed for 19±10 months. The segmented surface areas (antral, posterior, septal, and lateral) and dimensions (between the anterior and posterior walls, the right inferior PV and mitral annulus [MA], the right superior PV and MA, the left superior PV and MA, and the mitral isthmus) of the LA were evaluated three dimensionally using the NavX system. The cross-sectional areas of the PVs were also evaluated.ResultsAfter the follow-up period, 49 patients (73%) remained free from AF. A multivariate analysis showed that the diameter of the mitral isthmus and cross-sectional area of the right upper PV were associated with AF recurrence (odds ratio: 1.070, CI: 1.02–1.12, p=0.001; odds ratio: 0.41, CI: 0.21–0.77, p=0.006).ConclusionEnlargement of the mitral isthmus and a smaller right superior PV cross-sectional area were associated with AF recurrence

Effects of color–emotion association on facial expression judgments

Color and emotion are metaphorically associated in the human mind. This color–emotion association affects perceptual judgment. For example, stimuli representing colors can affect judgment of facial expressions. The present study examined whether colors associated with happiness (e.g., yellow) and sadness (e.g., blue and gray) facilitate judgments of the associated emotions in facial expressions. We also examined whether temporal proximity between color and facial stimuli interacts with any of these effects. Participants were presented with pictures of a happy or sad face against a yellow-, blue-, or gray-colored background and asked to judge whether the face represented happiness or sadness as quickly as possible. The face stimulus was presented simultaneously (Experiment 1) or preceded for one second by the colored background (Experiment 2). The analysis of response time showed that yellow facilitated happiness judgment, while neither blue nor gray facilitated sadness judgment. Moreover, the effect was found only when the face and color stimuli were presented simultaneously. The results imply that the association of sadness with blue and gray is weak and, consequently, does not affect emotional judgment. Our results also suggest that temporal proximity is critical for the effect of the color–emotion association (e.g., yellow–happiness) on emotional judgment

Cardiovascular risk assessment using LOX-index and Self-Rating Depression Scale

Objective: LOX-Index is a novel biomarker for cardiovascular disease (CVD) and is calculated by multiplying LOX-1 ligands containing apolipoprotein B (LAB) and soluble LOX-1 (sLOX-1). The Framingham risk score (FRS) is a common clinical tool for risk assessment of coronary artery disease. Mental stress can also be an important risk factor for CVD. The purpose of this study was to examine the relationship between LOX-Index and FRS or mental stress. Methods: LOX-Index was measured in 453 subjects including 150 consecutive outpatients with lifestyle-related diseases such as diabetes, hyperlipidemia, and hypertension and 303 healthy volunteers. Mental stress was evaluated by the Self-Rating Depression Scale (SDS). Results: LOX-Index was significantly related with the 10-years risk of FRS. Multiple regression analysis demonstrated that LAB was closely associated with the smoking status, low-density lipoprotein (LDL), and high-density lipoprotein (HDL). There were no significant associations between LOX-Index and the SDS scores; however, by simultaneously using LOX-Index and SDS, the subjects could be classified in terms of oxidative stress and mental stress. Conclusions: LOX-Index appears to be a comprehensive marker that could evaluate the status of multiple CVD risk factors. The classification with LOX-Index and SDS could contribute to the risk assessment for CVD

Prophylactic catheter ablation of ventricular tachycardia before cardioverter-defibrillator implantation in patients with non-ischemic cardiomyopathy: Clinical outcomes after a single endocardial ablation

Background: Outcomes related to prophylactic catheter ablation (PCA) for ventricular tachycardia (VT) before implantable cardioverter-defibrillator (ICD) implantation in non-ischemic cardiomyopathy (NICM) are not well characterized. We assessed the efficacy of single endocardial PCA in NICM patients. Methods: We retrospectively analyzed 101 consecutive NICM patients with sustained VT. We compared clinical outcomes of patients who underwent PCA (ABL group) with those who did not (No ABL group). Successful PCA was defined as no inducible clinical VT. We also compared the clinical outcomes of patients with successful PCA (PCA success group) with those of the No ABL group. Endpoints were appropriate ICD therapy (shock and anti-tachycardia pacing) and the occurrence of electrical storm (ES). Results: PCA was performed in 42 patients, and it succeeded in 20. The time to ES occurrence was significantly longer in the ABL group than in the No ABL group (p=0.04). The time to first appropriate ICD therapy and ES occurrence were significantly longer in the PCA success group than in the No ABL group (p=0.02 and p<0.01, respectively). Conclusion: Single endocardial PCA can decrease ES occurrence in NICM patients. However, high rates of VT recurrence and low success rates are issues to be resolved; therefore, the efficacy of single endocardial PCA is currently limited