Background: Spontaneous coronary artery dissection (SCAD) is an important cause of acute coronary syndrome (ACS). However, knowledge about the disease is limited and therefore SCAD might still be underdiagnosed. We analyzed trends in incidence, presentation, angiographic appearance, management, and outcomes of SCAD over 25 years.

Methods: Patients with diagnosis of SCAD between 1997 and 2021 at a tertiary referral hospital, were included. Incidences were analyzed as a total number and a proportion of ACS cases. Data on presentation, angiographic findings, management, and outcomes were collected from medical records. Major adverse cardiac events (MACE) were defined as the composite of all-cause death, cardiac arrest, SCAD recurrence or progression, any other myocardial infarction, and stroke.

Findings: One hundred fifty-six SCAD cases were included in this study. The incidence of SCAD increased significantly in total numbers (p<0·001) and relatively to ACS cases (p<0·001), as shown in figure 1. This was based on an increase of SCAD type 2 (p<0·001) and lesions in side branches (p=0·014), whereas the proportions of lesions in the left main coronary artery and proximal segments were decreasing (p-values 0·029 and <0·001, respectively). The detected SCAD lesions became shorter (p=0·004). The presentation of patients remained unchanged, and the rate of MACE (35%) was stable over the study period. However, there was an increase in conservative therapy (p<0·001). A reduced proportion of patients with need for intensive care treatment (p=0·017) despite stable cardiac biomarkers suggest a positive effect of conservative therapy. 

Interpretation: The incidence of SCAD increased distinctly, and SCAD represents an important cause of ACS that might be still underappreciated. The rise was based on higher numbers of more subtle lesions with a growing proportion of conservative management and a lower need for intensive care treatment.