Oral Presentation No. 006
Postoperative Myocardial Injury due to Platelet Reactivity in Patients undergoing Vascular Surgery

Postoperative myocardial injury (PMI) after major vascular surgery, detected by elevated cardiac troponin (cTn), has been associated with morbidity and mortality. It is unclear whether the pathophysiology of PMI is determined by increased platelet activity.

To examine the relationship between platelet activation (P-selectin expression) and PMI(cTn release as continuum) in patients undergoing elective open abdominal aortic surgery in the early post-operative period.

This prospective, single-centre, observational, cohort study included 33 patients undergoing elective open abdominal aortic surgery between March 2018 and April 2021. Patients were routinely treated with aspirin. Unstimulated platelet activation was measured by platelet bound P-selectin expression (range 0–100%). Explorative coagulation measurements were: stimulated platelet aggregation measured with the VerifyNow® assay (aspirin cartridge), with the Multiplate® analyzer (ASPI, ADP and TRAP) and stimulated coagulation status evaluated by the TEG® Haemostasis Analyzer System (global haemostasis cartridge). The primary outcome was cTn release assessed by the fifth generation high-sensitive cTn assay. Multivariable generalized linear mixed models were used to evaluate the association between platelet function and cTn concentrations over time.

Ten patients (29.4%) developed PMI. Increased P-selectin expression directly after surgery was associated with the cTn concentrations over 48 h (β = 1.39(1.1–1.75), P = 0.0064). No association was found between P-selectin measured later (at 24 h or 48 h) after surgery and cTn concentrations. Furthermore, there was no association between the explorative coagulation parameters and cTn release.

Increased P-selectin expression measured directly after surgery is associated with elevated cTn concentrations in the early postoperative period in patients undergoing elective open abdominal aortic surgery.