Bradycardia

Heart rate below the normal range

Bradycardia (from Ancient Greek βραδύς (bradús) 'slow' and καρδία (kardía) 'heart'), also called bradyarrhythmia, is a resting heart rate under 60 beats per minute (BPM). While bradycardia can result from various pathological processes, it is commonly a physiological response to cardiovascular conditioning or due to asymptomatic type 1 atrioventricular block. Resting heart rates of less than 50 BPM are often normal during sleep in young and healthy adults and athletes.

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