Case Report: Diagnostic pitfalls in localized aortic root dissection: two cases and a literature review.

Background: Localized aortic root dissection is a rare and distinct variant of aortic dissection, characterized by an intimal tear confined to the aortic root without distal propagation. Its nonspecific presentation and subtle imaging findings frequently result in diagnostic error. This report describes two cases and reviews the literature to highlight key imaging pitfalls and diagnostic considerations. Case presentation: In the first patient, transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) initially misidentified the dissection as a congenital supravalvular aortic membrane, while coronary computed tomography angiography (CTA) did not identify a definite aortic root dissection. The correct diagnosis was established intraoperatively. In the second patient, TTE and CTA were non-diagnostic, whereas TEE subsequently visualized the localized dissection. Notably, neither patient had significant aortic root dilatation, classic "tearing" chest pain, or features of connective tissue disease. Conclusion: Localized aortic root dissection presents with atypical symptoms and subtle, potentially confusing imaging features, leading to misdiagnosis or delayed recognition. In patients with severe aortic regurgitation of unclear etiology, this entity should be considered even in the absence of aortic root dilatation or typical tearing chest pain. Comprehensive morphological assessment of the aortic root is crucial. TEE offers a higher diagnostic yield than TTE or CTA and is useful for detection and differentiation; when clinically stable, early comprehensive TEE should be considered.