CONGRESS ABSTRACT

We present the case of a patient with a history of valvulopathy. In 2016, she underwent aortic valve replacement with a bioprosthetic valve (MitroFlow 21mm). One year later, she required replacement of the previously implanted bioprosthetic valve due to prosthetic endocarditis, with an Edwards Magna 21mm aortic bioprosthesis. She remained clinically stable until August 2024, when she presented with effort-induced dyspnea. Echocardiography revealed severe mitral regurgitation and moderate-to-severe tricuspid regurgitation. Left ventricular systolic function was normal, and the aortic bioprosthesis was functioning well. In October, the patient underwent mitral valve replacement and tricuspid annuloplasty. The procedure was complicated by atrial fibrillation and paroxysmal AV block, necessitating the implantation of a permanent pacemaker (PM). During the pacemaker implantation, angiography revealed stenosis of the superior vena cava, leading to abandonment of the transvenous approach (fig 1). A subsequent CT scan confirmed luminal narrowing of the distal segment of the superior vena cava at its junction with the right atrium, with minimal tissue thickening and small extra-luminal radiopaque images (approximately 60% stenosis, without endoluminal filling defects suggestive of thrombosis) (fig 2). This finding, likely related to prior cardiac surgeries, contraindicated the implantation of endocavitary electrode catheters. Consequently, a leadless pacemaker (AVEIR) was implanted in the septal region of the right ventricle, with excellent electrical parameters (fig 3). The procedure was well tolerated, though complicated by a hematoma at the access site, requiring a blood transfusion and resolved with suturing.