Atypical Recurrent Cystic Left Ventricular Thrombus in Non-ischemic Dilated Cardiomyopathy: When Follow-up Imaging Establishes the Diagnosis

Abstract

Background: Left ventricular thrombus is a recognised complication of severe ventricular dysfunction, but cystic morphology is rare and can mimic other intracardiac masses, creating diagnostic uncertainty when advanced imaging is unavailable. Case Presentation: A 72-year-old woman presented with progressive dyspnoea, orthopnoea, and bilateral lower-limb oedema. Transthoracic echocardiography demonstrated a markedly dilated left ventricle with severe global systolic dysfunction and a highly mobile, pedunculated, predominantly anechoic mass attached to the anterior and anterolateral left ventricular walls. Coronary angiography showed no significant coronary artery disease, supporting a non-ischaemic cause of the dilated cardiomyopathy. Cardiac magnetic resonance imaging was considered but could not be performed because of financial constraints. Hydatid serology was negative, and therapeutic anticoagulation was initiated together with guideline-directed medical therapy for heart failure. At one-month follow-up, echocardiography showed complete disappearance of the intracavitary mass, supporting a thrombotic origin. Six months later, after loss to follow-up and treatment discontinuation, a morphologically similar cystic-appearing mass recurred at the left ventricular apex. Conclusion: The complete response to anticoagulation and subsequent recurrence after treatment interruption supported the diagnosis of recurrent cystic left ventricular thrombus. Serial echocardiographic follow-up may therefore be particularly valuable when atypical thrombus morphology resembles a cystic cardiac mass and advanced tissue characterisation is not available.