Large coronary intramural hematomas: a case series and focused literature review

• This manuscript addresses a case series of a large spontaneous coronary intramural hematoma occurring in the aftermath after an episode of pronounced gastroenteritis, and two cases of large iatrogenic coronary intramural hematomas occurring as complications after percutaneous coronary intervention with stent implantation.
• The essential diagnostic and treatment-guiding role of intravascular ultrasound is highlighted in the case descriptions.
• Due to the rarity of cases and sporadic reporting of therapy experiences in the literature, no consensus concerning optimal treatment exists.
• In the discussion section of this manuscript a focused literature review summarizing published reports and required therapy is provided.
• Our findings/experiences indicate, that the coronary vessel wall might restitute by itself following isolated spontaneous coronary intramural hematoma, and percutaneous revascularization treatment should be restricted to patients with refractory ischemia.

Isolated spontaneous coronary intramural hematoma is a unique subset of spontaneous coronary artery dissection that is characterized by a hemorrhage limited to the medial–adventitial layers, causing subsequent hematoma formation without visible intimal flaps. It is an infrequent and serious coronary vessel wall pathology, with poorly understood underlying pathogenic mechanisms. Affected individuals may present with a broad spectrum of symptoms ranging from acute coronary syndromes (ACS) to cardiogenic shock or even sudden cardiac death. The disease entity causes challenges in terms of both diagnostics and treatment strategy. Coronary intramural hematomas can also occur iatrogenically, as a complication to percutaneous coronary intervention (PCI). Coronary angiography (CAG) has limited diagnostic value in the absence of intimal dissections, and lesions are often angiographically ambiguous. Intravascular ultrasound (IVUS) is an important diagnostic tool in establishing the correct diagnosis, as it provides a complete vessel wall assessment, and enables morphometric information regarding the magnitude and severity of the underlying hematoma. Due to the rarity of this clinical scenario, no randomized, controlled trials exist to guide treatment, and no consensus regarding management is available. Currently, treatment strategies are based on a case-by-case clinical assessment, and experiences described in previous, limited retrospective studies and case reports.