Sick sinus syndrome is associated with abnormal impulse initiation and propagation from the SAN. Patients affected by this disease have sinus bradycardia, sinus pauses or arrest, atrial chronotropic incompetence, and SAN exit block. Sick sinus node dysfunction occurs most commonly in older patients, but even healthy older patient show higher regularity and altered fractal scaling, consisting of a loss of complex variability. In the sick sinus patients, the average spread around the mean interval (quantified by Poincaré plot) is higher than in control patients. Similar results were documented in dogs with sick sinus syndrome
Last date updated on September, 2024