Résumé : Thromboembolic complications remain a frequent cause of morbidity and mortality in patients with a mechanical prosthetic heart valve. We report the case of a 57-year-old female patient admitted for acute respiratory distress. A thrombosis of the St Jude mitral valve was confirmed by transesophageal echocardiography. Surgery was planed, but brutal deterioration of her hemodynamic parameters and cardiac arrest prompted emergency thrombolysis. A LUCAS (Lund University Cardiopulmonary Assist System) chest compression device was used. Rapid recovery of valve mobility was obtained. Hypothesis of this rapid recovery and safety of LUCAS in this setting are discussed. © 2010 Elsevier Inc. All rights reserved.