7.8.1 Sinus bradycardia
Sinus bradycardia is an abnormally slow heart rate (<24 bpm) caused by infrebut regular sinus discharge. It can be associated with high vagal tone, myocardial depression, electrolyte disturbances, or high cerebrospinal fluid pressure. Auscultation will identify a slow regular rhythm. The ECG shows regular R-R intervals and normal QRS complexes. If the condition is physioloit will be abolished by excitement or exercise. However, it is usually pathological and may be associated with poor athletic performance. It is a rare condition. It is important to identify any underlying predisposing factors and treat these conditions rather than use atropine to try to increase the heart rate.