Clinical Electrophysiology (clinical + electrophysiology)

Distribution by Scientific Domains


Selected Abstracts


2245: Electrodiagnosis in inherited retinal disease

ACTA OPHTHALMOLOGICA, Issue 2010
GE HOLDER
Purpose To describe the roles of electrophysiology in the diagnosis and counselling of patients with inherited retinal disease. Methods Electrophysiological testing performed to incorporate and extend the recommendations of the International Society for Clinical Electrophysiology of Vision. Results Using a case-based presentation, it will be shown that electrophysiological testing can objectively assess the function of the different cell types and layers within the retina of the patient with inherited retinal dysfunction, which enables accurate diagnosis and counselling when placed in clinical context. The roles of pattern and multi-focal ERG in the assessment of macular function will be discussed. The electrophysiological findings will be discussed in relation to imaging studies when appropriate. It will shown that distinctive electrophysiological findings can direct appropriate and therefore cost-effective mutational screening in patients with atypical fundus changes. Conclusion Electrophysiological testing is fundamental to the successful management of patients with inherited disorders of retinal function. [source]


The VA Relationship After Differential Atrial Overdrive Pacing: A Novel Tool for the Diagnosis of Atrial Tachycardia in the Electrophysiologic Laboratory

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 11 2007
MITSUNORI MARUYAMA M.D.
Introduction: Despite recent advances in clinical electrophysiology, diagnosis of atrial tachycardia (AT) originating near Koch's triangle remains challenging. We sought a novel technique for rapid and accurate diagnosis of AT in the electrophysiologic laboratory. Methods: Sixty-two supraventricular tachycardias including 18 ATs (10 ATs arising from near Koch's triangle), 32 atrioventricular nodal reentrant tachycardias (AVNRTs), and 12 orthodromic reciprocating tachycardias (ORTs) were studied. Overdrive pacing during the tachycardia from different atrial sites was performed, and the maximal difference in the postpacing VA intervals (last captured ventricular electrogram to the earliest atrial electrogram of the initial beat after pacing) among the different pacing sites was calculated (delta-VA interval). Results: The delta-VA intervals were >14 ms in all AT patients and <14 ms in all AVNRT/ORT patients, and thus, the delta-VA interval was diagnostic for AT with the sensitivity, specificity, and positive and negative predictive values all being 100%. When the diagnostic value of the delta-VA interval and conventional maneuvers were compared for differentiating AT from atypical AVNRT, both a delta-VA interval >14 ms and "atrial-atrial-ventricular" response after overdrive ventricular pacing during the tachycardia were diagnostic. However, the "atrial-atrial-ventricular" response criterion was available in only 52% of the patients because of poor ventriculoatrial conduction. Conclusions: The delta-VA interval was useful for diagnosing AT irrespective of patient conditions such as ventriculoatrial conduction. [source]


Monophasic Action Potential Recordings in Humans

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 7 2007
HANS J. MOORE M.D.
Bridging basic and clinical electrophysiology has been facilitated by monophasic action potential recordings. The electrocardiogram is a useful clinical approach in detecting abnormal repolarization, but falls short in depicting local repolarization details. The MAP waveform is a reflection of local transmembrane action potentials. We hope to convey a basic understanding of monophasic action potential recording and highlight the clinical utility in both ventricular and atrial arrhythmias. [source]


Sudden Cardiac Death and Inherited Arrhythmia Syndromes

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 2005
ANDREA SARKOZY M.D.
Sudden cardiac death (SCD) at youth is rare and is often caused by inherited cardiac disorders. This review focuses on the genetic background of inherited primary electrical diseases, the so-called "channelopathies." Following a short clinical description of each syndrome, the recent findings in the genetics of long QT syndrome, short QT syndrome, isolated cardiac conduction defect, familial sick sinus syndrome, familial atrial fibrillation, cathecholaminergic polymorphic ventricular tachycardia, familial Wolff-Parkinson-White (WPW) syndrome, and Brugada syndrome are discussed. The currently proposed theoretical model of overlapping phenotypes in SCN5A sodium channel mutations is presented. The recent data indicate that advances in molecular genetics, experimental and clinical electrophysiology shed some light on the genetic background of primary electrical diseases. However, it is also becoming clear that the process from a mutation of a gene to the clinical presentation of a patient is currently only partially understood and extremely complex. [source]