Thrombolytic Therapy for Acute Mechanical Aortic Valve Thrombosis : A Case Report with Coronary Embolic Complication

Abstract

Background : Prosthetic valve thrombosis (PVT) is a rare but life-threatening complication of mechanical heart valves, particularly in the setting of subtherapeutic anticoagulation. Obstructive PVT in the aortic position can result in acute heart failure and sudden cardiac death. While emergency surgery is the recommended treatment, thrombolytic therapy may be considered when surgical access is limited or contraindicated. Case Summary : We report the case of a 69-year-old female with a mechanical aortic valve who presented with acute dyspnea and signs of cardiogenic shock following a 15-day interruption of vitamin K antagonist therapy. Transthoracic echocardiography revealed a severely elevated transaortic gradient, consistent with obstructive valve thrombosis. Due to the unavailability of emergency surgery, low-dose slow-infusion thrombolysis with tenecteplase was administered, resulting in rapid clinical and hemodynamic improvement. However, the patient developed a coronary embolism as a complication of thrombolysis, manifesting as anteroseptal ST-segment elevation and reduced left ventricular ejection fraction. Subsequent imaging confirmed restored prosthetic valve function. Discussion : This case illustrates the critical role of anticoagulation adherence in preventing mechanical valve thrombosis. Thrombolysis remains a life-saving alternative in emergency settings lacking surgical support, particularly when using slow-infusion protocols that optimize efficacy and reduce complications. Nonetheless, clinicians must remain vigilant for embolic events, including coronary embolism, which may present with atypical symptoms and contribute to myocardial dysfunction. Conclusion : In select patients with obstructive mechanical valve thrombosis and no access to surgery, thrombolysis is a viable option, but requires close monitoring for iatrogenic embolic complications. This case emphasizes the dual challenge of timely intervention and anticipation of thrombolysis-related risks. Take-Home Message : Lifelong adherence to anticoagulation is essential in patients with mechanical heart valves to avoid thrombosis and life-threatening complications. Patient education and regular monitoring are key to prevention. Thrombolysis can be lifesaving despite the occurrence of a severe embolic complication, this highlights both the risks of this therapy and the necessity to proceed when urgent intervention is required.