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Updated: Feb 9, 2026

High-resolution Optical Mapping of the Mouse Sino-atrial Node
Published on: December 2, 2016
A case of atenolol-induced sinus node dysfunction presenting as escape-capture bigeminy
1Department of Hospital/Internal Medicine, Marshfield Clinic, 1000 North Oak Avenue, Marshfield, WI 54449, USA.
Abstract:
Medications that are routinely used in clinical practice to treat hypertension such as beta blockers or non-dihydropyridine calcium channel blockers can depress sinus node function, resulting in symptoms and electrocardiographic changes consistent with sinus node dysfunction. In some patients, medications are potentially a reversible cause of apparent sinus node dysfunction. We report a patient who was taking atenolol for hypertension presented with recurrent near syncopal spells due to atenolol-induced sinus node dysfunction manifested in the form of an interesting and rare arrhythmia known as Escape-capture bigeminy.
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