High-risk thrombosis of a mechanical aortic valve: successful thrombolysis as a bridge or an alternative to surgery

Abstract

Thrombosis of a mechanical aortic valve prosthesis is a rare, yet potentially life-threatening complication that demands urgent recognition, rapid diagnostic evaluation, and immediate therapeutic intervention. We describe a detailed clinical case of a 52-year-old male patient who developed critical thrombosis of a mechanical aortic valve prosthesis despite maintaining an adequate and well-controlled anticoagulant regimen. The patient presented with profound hemodynamic instability, markedly reduced ejection fraction, and clinical manifestations consistent with acute decompensated heart failure. On physical and instrumental examination, his condition corresponded to ASA class IV, with a calculated surgical risk of EuroSCORE II=17.28%, indicating an extremely high perioperative mortality risk. Considering both the elevated risk of surgical re-intervention and the rapidly worsening heart failure, the multidisciplinary team decided to initiate systemic thrombolytic therapy as a life-saving alternative. Thrombolysis was performed according to an accelerated protocol using intravenous alteplase at a total dose of 100 mg. Within the first hour of infusion, echocardiography revealed a clear positive trend – restoration of leaflet mobility, a notable reduction in the transprosthetic gradient, and significant improvement in myo­cardial contractility. Subsequent management continued in the intensive care unit with careful hemodynamic and laboratory monitoring. The patient was discharged on the eighth day in a stable condition, free of complications. Follow-up echocardiography two months later confirmed normal and sustained function of the mechanical prosthesis. This case illustrates the high efficacy of systemic thrombolysis as a viable and guideline-supported (ESC/EACTS 2021, Class I, Level B) therapeutic option when surgical treatment is contraindicated or technically impossible.