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Updated: Oct 1, 2025

Voltage and Calcium Dual Channel Optical Mapping of Cultured HL-1 Atrial Myocyte Monolayer
Published on: March 23, 2015
Local inhomogeneous conduction and non-uniform anisotropism in a normal voltage atrial map
Pietro Rossi1, Filippo Maria Cauti2, Marco Polselli2
1Cardiology Division, Arrhythmology Unit, S. Giovanni Calibita Hospital, Isola Tiberina, Via Ponte Quattro Capi, 39, 00186, Rome, Italy. rossi.ptr@gmail.com.
Abstract:
A patient with symptomatic persistent atrial fibrillation and recurrences after pulmonary vein isolation (PVI) underwent a second ablation procedure. The PVs were found isolated and the left atrial substrate tissue was mapped. During sinus rhythm, the voltage map resulted in a normal range (>0,5mV) while a map of EGMs durations revealed an area presenting prolonged EGMs (>45 ms) in the anterior region. The activation map of this area demonstrated abnormal conduction and a non-uniform anisotropism when compared with areas in which EGM's normal durations were recorded. The EGMs duration map may offer additional clinical information on the areas presenting abnormal conduction predisposing arrhythmias maintenance in patients suffering from persistent atrial fibrillation.
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