P1454 A rare case of unexpected right atrial mass following aortic valve replacement
Authors: Varga A , Serban R C , Suciu C F , Suciu H , Tilea I 
Published: January 2020

Abstract

Funding Acknowledgements
This work was supported by the University of Medicine, Pharmacy, Science and Technology of Targu Mures Research Grant number 615/13/17.01.2019

Background
An early appearance of cardiac masses after valve replacement raises differential diagnosis problems. The specific therapeutic approach of autoimmune comorbidities enhances the risk of infective endocarditis or inflammatory reactions. Among systemic disorders leading to cardiac complications, rheumatoid arthritis is cited. Leflunomide is a synthetic disease-modifying antirheumatic drug (DMARD) with immunomodulatory actions as it inhibits the de novo synthesis of pyrimidine, hence suppressing T cell activation and proliferation. It is used as first line treatment strategy for rheumatoid arthritis (RA) patients, with contraindication or non-tolerance of Methotrexate.

Case presentation
We present the case of a 63-year old Caucasian male with seropositive RA, treated with Leflunomide 20 mg od, with history of severe calcified aortic stenosis and permanent atrial fibrillation. The patient underwent an aortic valve replacement with a St. Jude Regent 25 mechanical valve and ascending aorta replacement with a Dacron 30mm graft. Leflunomide was forthwith discontinued before surgery. Five months after surgery, in a routine check-up, including proper adherence to the anticoagulation regimen (regular INR 2.6-3.2), and stable hemodynamic status, a right atrial mass was identified by transthoracic echocardiography (figure). The mobile hyperechogenic mass appeared to be attached by a narrow stalk to the atrial septum, presenting a quasi-parallel movement to the septal cusp. The haemodynamic of the tricuspid valve was not affected. A suspicion of early infective endocarditis was ruled out. Cardiac CT identified a well-defined, pedunculated, mobile mass measuring 2.8x3.1 cm originating above the tricuspid annulus, attached to the atrial septum without hemodynamic impact. An inflammatory pseudotumor was identified and a granulomatous mass was diagnosed. Consecutively, Leflunomide 20 mg od along with adjusted doses of corticosteroids were initiated with progressively diminished dimensions of the tumour three months after the ultrasound and CT diagnosis. One year after complete resolution of the mass, the patient continues his immunosuppressive and cardiac pharmacological regimen. Repeated echocardiograms showed standard functionality of the aortic prosthesis, without recurrent intracardiac mass.

Conclusion
Management of an intracardiac mass after cardiac surgery in patients with systemic inflammatory diseases may be challenging. Cardiac imaging is mandatory to differentiate among thrombi, vegetations, primary or metastatic cardiac tumours.
In RA patients DMARD and immunosuppressive therapy should not be discontinuing during perioperative procedures as they do not increase the risk of infectious complications. Sequential imaging studies in patients presenting systemic inflammatory comorbidities should be used to assess and identify the immunological responses in the absence of targeted therapy.
Abstract P1454 Figure.