Pericoronary Adipose Tissue Attenuation in Patients with Spontaneous Coronary Artery Dissection According to Emotional Versus Physical Triggers: An Analysis from the INSIGHT-SCAD Study

Background: the pathophysiological mechanisms underlying spontaneous coronary artery dissection (SCAD) remain incompletely understood. Inflammation may play a pivotal role by promoting vascular susceptibility to SCAD. This study aimed to evaluate pericoronary adipose tissue (PCAT) attenuation, a recognized imaging marker of vascular inflammation, in patients with SCAD. Methods: patients with SCAD who underwent coronary computed tomography angiography (CCTA) within 48 h of the index event and with an identifiable trigger were included. Patients were classified according to the trigger preceding the event (emotional vs. physical). PCAT attenuation was measured in culprit and non-culprit vessels in all patients. Results: A total of 25 SCAD patients were included (mean age 55 ± 11 years, 80.0% female). Emotional triggers were reported in 17 patients (68.0%), while 8 (32.0%) experienced a physical trigger. Type 2 dissections were more common in the emotional trigger group (64.7% vs. 25.0%, p = 0.040). Patients with emotional triggers exhibited higher PCAT attenuation compared with those with physical triggers in the SCAD-related vessel (−62.35 ± 6.46 HU vs. −70.86 ± 8.45 HU; p = 0.028) and in non-culprit vessels (−61.39 ± 7.24 HU vs. −71.16 ± 5.28 HU; p = 0.001). Conclusions: patients with SCAD demonstrated elevated PCAT attenuation, particularly in those with emotional triggers, in both culprit and non-culprit vessels. These findings suggest that vascular inflammation may represent a predisposing factor for SCAD and a target for preventive and therapeutic strategies.