Prospective Study Protocol for Multiparametric PCCT Assessment of Early Ventricular Outcomes After CABG

The goal of this observational study is to learn whether information about heart muscle tissue from preoperative photon-counting CT, a newer type of CT scan, can help predict heart recovery 3 months after coronary artery bypass surgery. The study will include adults aged 18 years or older with coronary artery disease who are scheduled for coronary artery bypass surgery without another major heart operation. The main question it aims to answer is: \- Can heart muscle information from CT before surgery help predict the amount of blood remaining in the heart\'s left pumping chamber after it contracts, adjusted for body size, 3 months after surgery? This measurement is called the left ventricular end-systolic volume index and will be used to assess early changes in heart structure after surgery. Participants will: * Have photon-counting CT scans and heart ultrasound examinations before surgery, within 7 days after surgery, and approximately 3 months after surgery. * Have blood tests before surgery and within 7 days afterward to help researchers assess changes in heart muscle tissue. * Provide information about medications, hospital admissions, and their health during follow-up. Clinical doctors will determine surgery and treatment based on each participant\'s medical needs.