Intracardiac Thrombus Under Treatment With Daprodustat

An 84-year-old man was referred because of an intracardiac mass. He had persistent atrial fibrillation (AF) under therapeutic-range anticoagulation with warfarin, and chronic kidney disease. He had been started on daprodustat, a hypoxia-inducible factor prolyl hydroxylase inhibitor (HIF-PHI), 6 months earlier for the treatment of renal anemia. His hemoglobin levels improved, including iron-deficiency periods, from 8.8 to 14.6 g/dL, a high level for a patient with conservative renal failure. Transthoracic echocardiography revealed a mass in the left atrium (Figure A,B), and moderate aortic valve insufficiency. Computed tomography localized the mass to the left atrial anterior wall (Figure C,D). Surgical resection of the mass (Figure E,F), the maze procedure, left atrial appendage closure, and aortic valve replacement were performed to prevent emboli. Histologically, the mass was a thrombus (Figure G,H). At the 6-month follow-up, recurrent thrombus was not apparent while taking hematopoietic drugs other than HIF-PHIs.

Figure.

Transthoracic echocardiography shows a homogeneous mass in the left atrium (A, parasternal short-axis view (arrow); B, apical 4-chamber view (arrow)). Computed tomography shows the localization of the mass and a pedunculated part on the left atrial anterior wall (C, transverse plane; D, 3D reconstruction of the left atrium (blue structure) and the mass (yellow structure, 3.5×3.4×2.9 cm), which is separated from the left atrial auricle). Surgical view of the mass (E, arrows) identified through a right-sided left atrial incision, and the resected mass (F) with part of the left atrial wall (arrows). Histopathology shows no evidence of neoplastic changes, only thrombus, fibrin, and some myocardium (G, body of the mass; H, pedunculated part of the mass).

In this rare case, an intracardiac thrombus developed during oral administration of daprodustat. We recommend that patients receiving HIF-PHI treatment, unintentionally beyond the therapeutic range of hemoglobin levels and/or with iron deficiency, should undergo imaging to detect intracardiac thrombus, even when under anticoagulation. Additionally, magnetic resonance imaging may be useful in differentiating masses, as HIF-PHI treatment also carries a risk of developing malignancies.

Disclosures / IRB Information

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