Abstract Body: Introduction: Chest pain remains one of the most common and complex presentations in the emergency department (ED), requiring rapid and accurate identification of acute coronary syndrome (ACS). Arterial stiffness (AS), a novel noninvasive biomarker, could refine risk stratification for ACS in ED patients with chest pain. We conducted a feasibility study measuring AS in ED patients with chest pain.

Hypothesis: We hypothesized that one AS device would demonstrate superior feasibility.

Methods: This ongoing observational pilot study included adults (≥ 18 years) with chest pain and a negative initial troponin at the UNC Medical Center ED. Key exclusions were non-English speakers, critically ill patients, non-cardiac or trauma-related chest pain, and contraindications to AS testing. Eligible participants were identified through electronic health record (EHR) screening and confirmed in-person. After the first 11 participants were assessed under a three-device protocol, all subsequent participants completed the BP+ and were randomized to either the VaSera VS-2000 or SphygmoCor XCEL to reduce participant burden. Each participant completed two AS assessments: BP+ (one measurement repeated three times) and VaSera or SphygmoCor (two measurement sites per device, each repeated three times). Feasibility outcomes included assessment time, completion rates, and reasons for incompletion.

Results: Of 21 enrolled participants, 11 were assessed under the original three-device protocol, 5 were assigned VaSera and BP+, and 5 to SphygmoCor and BP+. Average assessment times were 32 minutes for VaSera, 30 for SphygmoCor, and 10 for BP+. Completion rates were 87%, 71%, and 95%, respectively. Incompletion most often resulted from subject discomfort (VaSera, BP+), clinical interruption (BP+), and technician error or device malfunction (SphygmoCor).

Conclusions: This pilot study is one of the first to implement AS measurements for chest pain in the ED. BP+ was the most time-efficient device, while VaSera had the highest completion rate. SphygmoCor presented the greatest challenges due to technician errors and device malfunctions. These findings highlight practical barriers to AS measurement and demonstrate that AS assessment is feasible in the ED. Future studies will evaluate its potential to inform ED decision making.