CONGRESS ABSTRACT

Anomalous circumflex coronary artery (ACCA) is a rare condition where the origin of the left circumflex artery (LCx) is in the right sinus of Valsava (RSV) or in the proximal right coronary artery (RCA). Part of the group of congenital coronary anomalies (CCA), these anatomical variants carry in some cases the risk of ischemic manifestations, including sudden cardiac death (SCD). However, that’s not the case for ACCA, as its retroaortic course is not associated with an extrinsic compression by the surrounding structures, unlike the interarterial course of other types of CCAs. Yet, ACCA risk of compression does exist, and it’s mainly correlated to the implantation of prosthetic devices during heart surgery or transcatheter procedures. Some echocardiographic signs could help to suspect the presence of the anomaly, but only computed tomography angiography (CTA) can confirm the diagnosis and rule out high-risk anatomical features. Invasive coronary angiography (ICG) and percutaneous coronary intervention (PCI) in the context of ACCA can be very challenging because of difficulties in cannulation and poor backup force. An intramural path in the aortic wall is assessable through intravascular ultrasound (IVUS) thanks to its good tissue penetration capacity. Surgery is recommended for symptomatic patients, especially with high-risk anatomy. We present a case of relapsing acute coronary syndrome (ACS) due to an early stent thrombosis of a recently stented ACCA in a 56 year-old hereditary hemorrhagic telangiectasia (HHT) patient. He had a history of anterior ST-Elevation Myocardial Infarction (STEMI) leading to advanced heart failure. Optical coherence tomography (OCT) allowed us to record an extrinsic compression of the anomalous artery involving the proximal edge of the stent: a slit-like tract followed by an accumulation of stent struts. PCI using only thromboaspiration restored the stent patency. As we did not perform CTA nor IVUS, while stabilizing the critical condition of the patient and preparing him for the transfer to the referral centre for heart transplatation, we could not exclude an interarterial course or an intramural path. A rare disease predisposing to bleeding and ischemic complications and an unsuspected malignant behaviour of a usually benign anomaly made this case unique. Whether the stent thrombosis derived from its compression or whether HHT played a crucial role, that is the open question of our report.