Invasive Management and 1-Year Outcomes in Patients Aged ≥75 Years with Acute Coronary Syndrome: Age and Clinical Vulnerability

Background/Objectives: Older adults with acute coronary syndrome (ACS) are clinically heterogeneous, and treatment decisions should not rely on chronological age alone. We examined associations of age and clinical vulnerability with coronary angiography, subsequent percutaneous coronary intervention (PCI), and mortality in patients aged ≥75 years. Methods: We retrospectively studied 1043 consecutive patients hospitalized with ACS between January 2021 and April 2026. Clinical vulnerability was assessed using the exploratory, study-specific Senior ACS Clinical Vulnerability Score (SAF-75). Results: Mean age was 81.0 years; 47.6% were women. Coronary angiography was performed in 571 patients (54.7%) and PCI in 208 (19.9%). Angiography declined from 68.6% at age 75–79 years to 30.1% at ≥85 years. Age was independently associated with lower odds of angiography (OR 0.86 per year, 95% CI 0.82–0.89; p < 0.001), but not with subsequent PCI among patients undergoing angiography (OR 1.01, 95% CI 0.95–1.06; p = 0.852). In-hospital and Kaplan–Meier estimated 1-year mortality were 18.1% and 35.7%. Greater vulnerability was associated with lower angiography use and higher mortality; no independent association with PCI after angiography was detected. Conclusions: Age-related and vulnerability-related differences were most evident at angiography selection. SAF-75 was strongly associated with prognosis but requires external validation.