Risk Score for the Event of Perioperative Myocardial Infarction at the Time of Carotid Endarterectomy

The purpose of this study was to create a risk score for the development of perioperative myocardial infarction (MI) following carotid endarterectomy (CEA) utilizing weighted variables from the Vascular Quality Initiative (VQI) database, which have a multivariable significant association with the event.

The VQI CEA module was queried between January 2003 and October 2023, and 192,547 procedures met the study inclusion criteria. Both symptomatic and asymptomatic patients were included. An internal VQI validation cohort was similarly created with the same exclusion criteria utilizing CEA performed between November 2023 and October 2024, over which time period 17,449 individuals met the inclusion criteria. The primary study outcome was perioperative MI at CEA. Univariable analysis was conducted followed by binary logistic regression analysis utilizing significant univariable factors. Regression beta coefficient was used to create a weighted risk score for MI and internal validation with testing at each risk score was conducted. Mortality rates in long-term follow-up for those with versus without MI were investigated.

MI occurred in 0.7% of cases (N = 1,299). The following factors had a significant (P < 0.05) multivariable association with perioperative MI for CEA: female sex; advancing age; rural home status; diabetes; history (Hx) of coronary artery disease (CAD); MI or angina pectoris within 6 months of surgery; coronary artery bypass grafting > 5 years ago; congestive heart failure regardless of severity; renal insufficiency; positive stress test within 2 years; anemia; Hx of peripheral arterial disease intervention; prior CEA or carotid artery stenting; dual antiplatelet therapy at time of presentation; modified Rankin score ≥2 at time of CEA; and urgent/emergent CEA. Not having had a Hx of prior MI in combination with having no current CAD symptom was protective (P < 0.001) for perioperative MI. There was significant escalation noted with increasing risk score as patients with scores of ≤5 experienced MI in just 0.2% of cases whereas patients with risk scores of >25 experienced MI at a >20 times higher rate of 4.1%. Area under the curve (AUC) analysis for the risk score had a value of 0.70. Application of the risk score to the validation cohort resulted in a similar AUC value of 0.72.

A risk score for the event of perioperative MI at the time of CEA has been developed that has good accuracy. Patients experiencing perioperative MI have a significantly increased 5-year mortality rate relative to those without. Given the significant impact of perioperative MI on long-term survival, this risk score has important implications for perioperative cardiac risk assessment and optimization strategies.