Objectives The aim of this study was to conduct a nationwide all comer description of incidence, contemporary management and outcome in Swedish spontaneous coronary artery dissection (SCAD) patients. The incidence of SCAD as well as the management and outcome of these patients is not well described. Design A nationwide observational study. Participants and setting All patients with SCAD registered in the Swedish Coronary Angiography and Angioplasty Register from 2015 to 2017 were included. The index angiographies of patients with registered SCAD were re-evaluated at each centre to confirm the diagnosis. Patients with non-SCAD myocardial infarction (MI) (n=32 601) were used for comparison. Outcome measures Outcomes included all-cause mortality, reinfarction or acute coronary reangiography. Results This study found 147 SCAD patients, rendering an incidence of 0.74 per 100 000 per year and a prevalence of 0.43% of all MIs. The average age was 52.9 years, 75.5% were women and 47.6% presented with ST-segment elevation MI. Median follow-up time for major adverse cardiac event was 17.3 months. Percutaneous coronary intervention was attempted in 40.1% of SCAD patients and 30.6% received stent. The use of antithrombotic agents was similar between the groups and there was no difference regarding outcomes, 10.9% vs 13.4%, p=0.75. Mortality was lower in SCAD patients, 2.7% vs 8.0%, p=0.03, whereas SCAD patients more often underwent acute reangiography, 9.5% vs 4.6%, pConclusion In this nationwide, all comer Swedish study, the overall incidence of SCAD was low, including 25% men which is more and in contrast to previous studies. Compared with non-SCAD MI, SCAD patients were younger, with lower cardiovascular risk burden, yet suffered substantial mortality and morbidity and more frequently underwent acute coronary reangiography.

Aims: Spontaneous coronary artery dissection (SCAD), causing acute coronary syndrome (ACS), primarily in middle-aged women, is diagnosed with invasive coronary angiography (ICA). Due to the risk of dissection propagation with ICA, a non-invasive diagnostic tool is needed. We investigated coronary computed tomography angiography (CCTA) findings in acute SCAD, as well as the inter-modality agreement between CCTA and ICA. Methods and results: Thirty-two (92 % women, mean age 52.4 years) SCAD patients at eight Swedish hospitals were investigated with ICA as well as dual source CCTA during the index hospitalisation between April 2021 and October 2022. ICA identified 46 dissected segments whereas CCTA detected 25, Cohen's kappa (kappa) = 0.595 (95 % confidence interval [CI] 0.46-0.73). CCTA primary and secondary features were identified in 24 dissected coronary artery segments in 21 patients, 8 (32 %) tapered luminal stenosis, 11 (44 %) abrupt luminal stenosis, 3 (12 %) visible dissection membrane, 4 (16 %) intramural-hematomas, 9 (36 %) epicardial fat stranding and 8 (25 %) with coronary artery tortuosity. ICA identified 3 dissected proximal segments whereas CCTA identified 5, (kappa = 0.74, 95 % CI 0.40-1.00). In distal segments, ICA identified 43 and CCTA 20 dissections, (kappa = 0.57, 95 % CI 0.43-0.72). Conclusions: In patients presenting with acute SCAD, CCTA should not be considered a substitute for ICA. While CCTA demonstrated good diagnostic performance in identifying proximal SCAD lesions, its sensitivity was notably reduced in distal coronary segments, where SCAD is more frequent. Among the 25 lesions detected, CCTA successfully detected specific features in 24 lesions.