RESUMO
A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.
RESUMO
An easy-to-use assessment for activated factor X (FXa) is lacking despite its pivotal role in the coagulation. Dielectric blood coagulometry (DBCM) was recently invented as a novel assessment tool for determining the whole blood coagulability by measuring the temporal change in the permittivity of blood. We previously reported that it could evaluate the global blood coagulability. This study aimed to apply the DBCM for assessing FXa activity and its inhibition by anticoagulants. We performed the DBCM analysis along with measurement of the FXa activity by a fluorometric assay in samples from healthy subjects, and identified a new index named maximum acceleration time (MAT) that had a correlation to the FXa activity. Next the DBCM analysis was performed using blood samples mixed with anticoagulants (unfractionated heparin, dalteparin, and edoxaban). Blood samples with three anticoagulants had different profiles of the temporal change in the permittivity, reflecting their different selectivity for FXa. We compared the MAT with the anti-FXa activity assay, and found that the prolongation of MAT was similarly correlated with the anti-FXa activity regardless of the type of anticoagulants. In conclusion, the DBCM has the possibility for evaluating the innate FXa activity and effect of anticoagulants focusing on their FXa inhibition.
Assuntos
Anticoagulantes/farmacologia , Testes de Coagulação Sanguínea/métodos , Coagulação Sanguínea/fisiologia , Impedância Elétrica , Inibidores do Fator Xa/farmacologia , Fator Xa/metabolismo , Adulto , Coagulação Sanguínea/efeitos dos fármacos , Feminino , Humanos , MasculinoRESUMO
INTRODUCTION: Pulmonary vein isolation (PVI) using a cryoballoon (CB) is a useful tool for treating atrial fibrillation (AF); however, the clinical efficacy of the CB has never been fully investigated in patients with a left common pulmonary vein (LCPV). METHODS AND RESULTS: Three hundred twenty-four consecutive paroxysmal AF patients underwent PVI with a CB. Three-dimensional computed tomography was performed in all patients before the ablation. The clinical outcomes of the AF ablation between patients with (Group A) and without an LCPV (Group B) were compared. An LCPV was observed in 27 (8%) patients. There were no significant differences in the procedure time (149 ± 45 min vs. 143 ± 40 min, respectively; P = 0.42) and percentage needing touch up ablation between the 2 groups (26% vs. 20%, respectively; P = 0.45). At a mean follow-up of 454 ± 195 days, 282 of 324 (87%) patients were free from any atrial tachyarrhythmias (ATs) after a single procedure. Twenty out of 27 (74%) Group A patients and 262 of 297 (88%) Group B patients were free from ATs (15-month Kaplan-Meier event free rate estimates, 77% and 89%, respectively; P = 0.02). A multivariate analysis identified the presence of an LCPV and the left atrial diameter as reliable predictors of recurrent ATs. CONCLUSIONS: The long-term clinical outcomes of ablation of AF with the CB was worse in patients with an LCPV than in those without. The presence of an LCPV and the LA size seemed to be reliable predictors of a worse outcome.