People with palpitations should worry if palpitations are common or persistent for more than a week, with pain and loss of consciousness, medical attention should be sought immediately. If palpitations are a sign of an underlying heart condition, possible complications include; fainting due to quick heart beats which may cause blood pressure to drop, the heart stops beating effectively(cardiac arrest), heart failure and stroke which may damage a portion of the brain or lead to death.
Attribution: Straight Talk Foundation