Introduction: Occurrence of ventricular pause of more than 6 seconds following administration of 20 mg b&s of intravenous adenosine (ATP test) has been observed in a relatively high percentage of patients (pts) with unexplained syncope. However, these results have been reported in a relatively limited number of pts in only 2 series. The aim of OUT study was to assess the prevalence of this entity and pts' characteristics with positive ATP test in a larger single-center study.Methods: Pts were recruited consecutively based on following criteria: 1) at least one syncopal episode defined according to ESC guidelines, 2) no diagnosis after the usual work up, including systematically: clinical evaluation, orthostatic hypotension, ECG and when necessary, carotid sinus massage, electrophysiological study, and tilt table test. ECG was continuously monitored during and after ATP test and a ventricular pause longer than 6 seconds was considered as abnormal.Results: Among the 109 pts with unexplained syncope after a complete evaluation, 7 had a positive ATP test (6.4%). When compared to negative ATP group, pts with positive ATP test had the following characteristics: female predominance (85.7% vs 49.5%, p=O.OQ signiiicmtly older age (75.4&11X vs 56.1&17.8 years, p
Lidocaine use may lead to methemoglobinemia. Lidocaine is clinically widely used as an anaesthesic drug, however its toxic effect is rare. We report a high methemoglobinemia level of 31.1 % following repeated Xylocaine® gel oral applications. New metabolic pathways of lidocaine have been reported leading to dimethylphenylhydroxylamine in humans. This metabolism is very similar to the aniline derivative ones, and may explain lidocaine methemoglobinemia effect.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.