If the patient suddenly wakes up with a fast heartbeat: 1. Sympathetic overexcitation should be considered, for example, when the patient has poor sleep quality or excessive mental tension or anxiety, drinks strong coffee or tea before bedtime, smokes a lot, abuses alcohol, and has symptoms of sympathetic overexcitation such as sudden waking up with tachycardia when there is a disorder of the vegetative nerves. 2. If the patient has a history of diabetes, such as paroxysmal hypoglycemia at night, there will be sudden awakening, tachycardia, accompanied by body weakness, sweating and other symptoms. 4, if the patient suffers from hyperthyroidism and other conditions, there will also be the above clinical symptoms and performance.