SEVERITY, NOT PRESENCE, OF DIASTOLIC DYSFUNCTION DRIVES PERIOPERATIVE CARDIOVASCULAR RISK BEFORE NON-CARDIAC SURGERY: A PROSPECTIVE COHORT STUDY PROPOSING A SEVERITY-FIRST TRIAGE FRAMEWORK

Background: Diastolic dysfunction ( DD ) with preserved ejection fraction is prevalent before non-cardiac surgery, yet its prognostic weight remains contested. Guidelines flag DD without an actionable threshold. We hypothesized that DD severity, indexed by elevated left ventricular filling pressures (LVFP), drives perioperative risk. Methods: This prospective single-center cohort enrolled 102 adults scheduled for elective non-cardiac surgery (March 2025 to February 2026). All underwent preoperative transthoracic echocardiography per 2016 ASE/EACVI criteria. Isolated DD was preserved left ventricular ejection fraction (LVEF) - 50% with abnormal diastolic function. The primary endpoint was in-hospital major adverse cardiovascular events (MACE), comparing isolated DD (n = 44) and normal controls (n = 36). Performance used logistic regression with bootstrap-corrected area under the curve (AUC).