Sex Differences in the Diagnosis, Management, and Outcomes of Suspected Non-ST-Elevation Acute Coronary Syndromes Meeting Rapid Rule-Out Criteria

(1) Background: patients who meet current rapid rule-out criteria for myocardial infarction (MI) are considered low risk, yet their management remains nebulous, especially among women. We aimed to examine sex differences in the diagnosis, management, and outcomes of patients meeting the rapid rule-out criteria. (2) Methods: by simulating application of the rapid rule-out MI criteria, we analyzed consecutively triaged men and women with suspected NSTE-ACS who had high-sensitivity cardiac troponin T (hs-cTnT) values that met criteria (n = 11,477), in particular, those who were admitted (n = 3775). (3) Results: men constituted ~55% of triaged patients who met the rule-out criteria, whether admitted or discharged. Men were more likely to be admitted (33.7% vs. 31.9%, p = 0.04), more commonly with hs-cTnT values between level of detection (LOD, 5 ng/ml) and the 99th percentile (59.4% of all admissions vs. 40.5% for women), whereas women were more likely to be admitted with values < level of blank (LOB, 3 ng/mL; 22.9% vs. 9.2% for men). Thirty-day mortality (1 man and 1 woman) and in-hospital MI (9 men vs. 1 woman) were uncommon among admitted patients, yet resource utilization during 3–4 hospitalization days was substantial for both sexes, with men undergoing coronary angiography (6.8% vs. 2.9%) and revascularization (3.4% vs. 1.1%) more commonly. Long-term survival for both men and women, whether admitted or discharged, was significantly worse for hs-cTnT values between LOD and the 99th percentile, even after adjusting for age and cardiovascular comorbidities. (4) Conclusions: reporting actual hs-cTnT values < 99th percentile allows for better risk stratification, especially for women, possibly closing the sex gap.