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.

Clinical trial registration: NCT01933581.