<Tr> <Th> MeSH </Th> <Td> D001146 </Td> </Tr> <Tr> <Td_colspan="2"> (edit on Wikidata) </Td> </Tr> <P> Sinus bradycardia is a sinus rhythm with a rate that is lower than normal . In humans, bradycardia is generally defined to be a rate of under 60 beats per minute . </P> <P> The decreased heart rate can cause a decreased cardiac output resulting in symptoms such as lightheadedness, dizziness, hypotension, vertigo, and syncope . The slow heart rate may also lead to atrial, junctional, or ventricular ectopic rhythms . </P>

Which sinus rhythm has a rate of less than 60 beats per minute