For patients with osteoporosis undergoing heart valve replacement surgery, the main risks include: 1. Increased risk of fractures: Osteoporosis makes bones fragile, and movements during surgery may lead to fractures. 2. Prolonged healing time: Osteoporosis can slow down the healing process of bones and surgical wounds, extending recovery time. 3. Surgical complications: Osteoporosis may increase the risk of surgery-related complications, such as infection or bleeding. 4. Postoperative rehabilitation challenges: Patients with osteoporosis may face more difficulties during postoperative recovery, requiring more medical support and rehabilitation. Therefore, a comprehensive assessment of the patient's health is needed before surgery, along with appropriate protective measures.