Sternum midline incision can offer better view under open-heart surgery and bigger operating space, and therefore it has been widely used in most cardiac surgery. If an event of urgency occurs, it takes on a more important role than infrasternal small incision. However, sternum midline incision may cause serious pain and aggravates stress response, and therefore patients are often reluctant to cooperate to cough which exerts adverse effect on postoperative rehabilitation, and even causes serious complications such as pulmonary inflammation, myocardial infarction and heart failure. Thus, the relief of pain and better perioperative analgesia are very important for these patients. Transversus thoracic muscle plane(TTMP) block and erector spinal muscle plane(ESP) block are used in open heart surgery currently, and they can provide good analgesia. This study aimed to investigate the hemodynamic stability, total amount of analgesic use, perioperative pain, stress response, postoperative complication and recovery in patients receiving TMP and ESP.

Inclusion Criteria:

• patients (18-75 years) with BMI at 18-25 kg/m2, ASA Ⅱ- Ⅲ and NYHA Ⅱ-Ⅲ who scheduled to undergo mitral valve or aortic valve replacement surgery.

Exclusion Criteria:

• a second operation, preoperative ejection fraction (EF) < 40%, complicated coronary heart disease, intra-aortic balloon counterpulsation (IABP) support, psychiatric abnormalities, history of allergy to anesthetic drugs, liver or kidney dysfunction, coagulation abnormality, endocrine system diseases and metabolic diseases.