499 What light through yonder window breaks? Benefits of optical coherence tomography (OCT) in a case of spontaneous coronary artery dissection
Authors: Maino Alessandro , Vergallo Rocco , Ricchiuto Alfredo , Lombardi Marco , Buonpane Angela , Bianchini Emiliano , Romagnoli Enrico , Aurigemma Cristina , Burzotta Francesco , Trani Carlo , Crea Filippo 
Published: December 2021

Abstract

Aims
Spontaneous coronary artery dissection (SCAD) is a non-traumatic and non-iatrogenic separation of the coronary arterial walls, creating a false lumen. SCAD is an infrequent and often missed diagnosis especially in women presenting with acute coronary syndrome and in the majority of cases angiography alone could be insufficient for identification.

Methods and results
A 43-year-old woman presented to the Emergency Department of Fondazione Policlinico Universitario A. Gemelli IRCCS (Rome, Italy) for oppressive acute chest pain radiated to the right jaw, resolved spontaneously within a few minutes. Physical examination, including cardiovascular evaluation, was normal. High-sensitivity troponin was 152 ng/l and 250 ng/l in two serial determination (reference range, 0.0–37 ng/l). EKG showed sinus rhythm with no significant ST-segment alterations. Echocardiography revealed preserved biventricular systolic function with mild hypokinesia of the apical segments of the left ventricle. A diagnosis of NSTEMI was made based on clinical and laboratory parameters. Thus, urgent coronary angiography was performed, which demonstrated a single vessel disease with an eccentric, and angiographically complex stenosis of the proximal left anterior descending (LAD) artery with an image of plus compatible with a plaque ulceration. In order to define the extension of the disease and ostium involvement for a better procedural planning, OCT imaging was performed. Surprisingly, OCT showed a intramural haematoma extending from the ADA ostium to the proximal tract (approximately 22 mm) with ulceration in the body, minimal lumen area (MLA) 2.0 mm2 and evidence of normal trilaminar structure of the vessel both on downstream and upstream of the lesion. The angiographic features were compatible with type 2A SCAD. The therapeutic management was conservative with continuation of the double antiplatelet therapy and remote CT monitoring. Three days later, because of a new onset of chest pain and slight elevation of the ST segment on EKG, was performed a coronarographic control: the angiographic appearance of the lesion was substantially unchanged; OCT showed unmodified longitudinal extension of the lesion (about 22 mm) and relative increase in the endoluminal caliber compared to the previous examination (MLA 4.0 mm2).After 2 weeks, coronary CTA control was carried out, which documented the stability of the intramural hematoma in the proximal LAD, extended for 22 mm and with a maximum thickness of 2 mm, determining lumen narrowing of 40–45% The patient was discharged on medical therapy and no events occurred during the follow-up. Six month later, repeat CTA showed a complete resorption of the intramural haematoma.

Conclusions
In this case we highlight the utility of intravascular imaging, in particular OCT, in the evaluation of angiographic lesions of non-univocal interpretation and how its use can change the management and prognosis of ACS patients. Furthermore, the spontaneous resolution of the clinical and anatomical scenario through conservative treatment additionally confirms spontaneous healing as the natural history of SCAD and foreground the role of precise diagnosis (and intravascular imaging showed to improve it) for therapy shift and calibration.