Ciprofol, a novel intravenous general anesthetic with a chemical structure akin to propofol, boasts significantly enhanced potency. It offers a rapid onset, reduced incidence of injection pain, and minor impact on the cardiovascular system. However, clinical research regarding ciprofol's use for anesthesia induction in cardiac surgery remains limited. The investigators want to assesse the safety and effectiveness of ciprofol in cardiac surgery anesthesia

Inclusion Criteria:

1. Elective surgery patients
2. Aged 55 to 75
3. New York Heart Association class II or III cardiac functions
4. Median sternotomy approach for coronary artery bypass grafting or heart valve replacement procedures.

Exclusion Criteria:

1. With a history of benzodiazepine allergy
2. Significant liver or kidney insufficiency
3. Coagulation dysfunction
4. Neurological or psychiatric disorders
5. Undergone major surgery within the past three months.