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The electrical impulse moves through the heart as it contracts between 60 to 140 times a minute, depending on age of person. The contractions of ventricles represents a single heartbeat. Atria contraction is a little faster then the ventricles so the blood empties into the ventricle before their contraction.

The electrical impulse moves through the heart as it contracts between 60 to 140 times a minute, depending on age of person. The contractions of ventricles represents a single heartbeat. Atria contraction is a little faster then the ventricles so the blood empties into the ventricle before their contraction.