Abstract 4142798: Differences in Clinical presentation in Spontaneous Coronary Artery Dissection vs. Type 1 Myocardial Infarction

Background: Spontaneous coronary artery dissection (SCAD) refers to the nontraumatic, non-iatrogenic, and nonatherosclerotic separation of the coronary artery wall leading to acute coronary syndrome. This condition predominantly affects women with minimal or no traditional cardiac risk factors. We aimed to determine the differences in clinical presentation between SCAD and Type 1 myocardial infarction (MI) in the Aurora Health Care community. Methods: A retrospective, matched cohort, multicenter community study was carried out on adult patients aged >18 years admitted to all Aurora Hospitals from January 2012 to December 2022. A total of 57 patients were diagnosed with SCAD during that period. SCAD group and Type 1 MI group were matched by age and gender at a 1:5 ratio using a propensity score-based matching. Outcomes between the SCAD and the Type 1 MI groups were compared using chi-squared tests or Fisher’s exact tests, and t-tests or nonparametric equivalents (Wilcoxon). Results: A higher percentage of Type 1 MI patients presented as NSTEMI compared to SCAD patients (70% vs. 59.6%, p=0.028). Although not statistically significant, SCAD patients had a higher occurrence of STEMI than Type 1 MI patients (42.1% vs. 32.6%, p=0.169). On admission, SCAD patients had a higher maximum troponin (12,000 vs. 3,550, p=0.012). Type 1 MI patients had higher HgbA1C (6 vs. 5.4, p=0.0008). Both patients had similar LDL levels, but Type 1 MI had lower HDL levels (44 vs. 48, p=0.024). ESR, CRP, and D-dimer levels showed no significant difference. LV ejection fraction was 53% in both groups, and the LV global longitudinal strain was similar. The Type 1 MI group exhibited higher grades of diastolic dysfunction (Grade 2 and Grade 3) and mitral valve disease. E/e was higher in Type 1 MI compared to SCAD (11.5 vs 8.8, p <0.0001). Type 2 SCAD was most prevalent at presentation, with the most frequently affected artery being LAD (47.4%) and the most frequently affected branch vessel being obtuse marginal (36.4%). The most common location was distal (59.6%), followed by mid (22.8%), with the diameter of the vessel involved mostly between 2-3.5 mm. Conclusion: This study observed that although more SCAD patients presented as STEMI with higher troponins, Type 1 MI patients were sicker overall. These differences in clinical findings can aid in diagnosis as the management of these two populations differ.