A bad heart can cause insomnia, which may be related to nighttime angina, dyspnea in heart failure, arrhythmia, or emotional anxiety caused by recurrent cardiac symptoms. 1. Patients with coronary artery disease may experience myocardial ischemia at night leading to angina pectoris, which disrupts the patient’s sleep and leads to insomnia. 2. Heart failure can be associated with varying degrees of dyspnea, including nocturnal paroxysmal dyspnea, in which the patient suddenly wakes up after falling asleep due to breathlessness and needs to sit up to relieve it, which seriously affects the quality of sleep and may eventually lead to insomnia. 3. Arrhythmia: nocturnal arrhythmia, such as idiopathic sinus tachycardia, atrial fibrillation, supraventricular tachycardia, etc., may cause palpitations, sympathetic excitation, and difficulty in falling asleep. 4. In addition to the insomnia caused by the above nocturnal episodes, the recurrence of long-term chronic heart disease symptoms affects the quality of life, and can lead to insomnia due to anxiety. The symptoms of heart disease should be treated promptly under the guidance of a doctor.