iFR Guided Coronary Artery Bypass Grafting Surgery

This study evaluates whether using a pressure measurement called iFR (instantaneous wave-free ratio) to guide which arteries are bypassed during coronary artery bypass graft (CABG) surgery leads to better outcomes than standard approaches. CABG surgery creates new routes for blood to flow around blocked arteries in the heart, and iFR helps determine which blockages are truly limiting blood flow and thus most important to bypass. Not all visible blockages in the arteries actually restrict blood flow significantly. Operating on arteries that aren't truly causing a problem adds risk without benefit. iFR is a technique already used in stenting procedures to identify 'functionally significant' blockages, and this study tests whether applying this data to surgical planning improves long-term outcomes after bypass surgery. **You may be eligible if...** - You are between 25 and 80 years of age - You understand and have signed the informed consent form - You are scheduled for elective (non-emergency) first-time CABG surgery in isolation (no other concurrent procedures) - You have pre-operative coronary angiography data with iFR measurements available **You may NOT be eligible if...** - You need emergency CABG surgery - Your heart ejection fraction is 40% or below - You have severe valve disease of the heart **Talk to your doctor** about your angiography results, your heart function, and whether your CABG surgery is planned as an elective, first-time procedure.