Non-invasive vascular measures as prognostic predictors for older patients with non-ST elevation acute coronary syndrome

Background Adverse cardiac events are common in older patients with non-ST elevation acute coronary syndrome (NSTEACS), yet prognostic predictors are still lacking. This study investigated the long-term prognostic significance of non-invasive measures including endothelial function, carotid intima-media thickness (CIMT), and vascular stiffness in older NSTEACS patients referred for invasive treatment. Methods NSTEACS patients aged 75 years and older recruited to a multicentre cohort study (NCT01933581) were assessed for baseline endothelial function using endoPAT logarithm of reactive hyperemia index (LnRHI), CIMT using B-mode ultrasound, and vascular stiffness using carotid-femoral pulse wave velocity (cfPWV). Long-term outcomes included major adverse cardiovascular events (MACE), a composite of death, reinfarction, urgent revascularization, stroke/transient ischemic attack, and significant bleeding. Results Recruitment resulted in 214 patients assessed for LnRHI, 190 patients assessed for CIMT and 245 patients assessed for cfPWV. For LnRHI group (median follow-up 4.73 years [IQR: 1.41–5.00]), Cox regression analysis revealed a trend towards increased risk of MACE (HR: 1.24 [95% CI: 0.80–1.93]; P = 0.328) and mortality (HR: 1.49 [95% CI: 0.86–2.59]; P = 0.157), but no significance was reached. No difference for other components of MACE was found. For CIMT group (median follow up 4.74 years [IQR: 1.55–5.00]), no statistically significant difference in MACE was found (HR: 0.92 [95% CI: 0.53–1.59]; P = 0.754). Similarly, for cfPWV group (median follow-up 4.96 years [IQR: 1.55–5.00]), results did not support prognostic significance (for MACE, HR: 0.95 [95% CI: 0.65–1.39]; P = 0.794). Conclusion Endothelial function, CIMT and vascular stiffness were proven unsuitable as strong prognostic predictors in older patients with NSTEACS.