ABSTRACT
INTRODUCTION AND IMPORTANCE: COVID-19 represents a new challenge for patients with prosthetic valve, through increasing the risk of thrombosis and reducing the frequency of anticoagulation follow up visits. CASE PRESENTATION: A 37-year-old male patient on aspirin and warfarin for a mechanical aortic valve (AV, St Jude size 21 mm), presented with generalized fatigue and loss one of the mechanical heart sounds for 10 days. Urgent fluoroscopy showed stuck one of the AV leaflets in a closed and opening positions. Echocardiography showed high peak and mean AV gradients. The patient was confirmed with COVID-19 with fever on the day of admission. Cardiac CT with contrast showed stuck right (posterior) disc with a 6 × 4 mm thrombus surrounded by pannus formation. The patient was started on ultraslow thrombolytic therapy (alteplase 1 mg, every hour for 25 h, followed by 6 h of unfractionated heparin). Repeated fluoroscopy showed normal opening and closure of both discs. Repeated echocardiography showed a significant reduction in the peak and mean AV gradients back to baselines. The patient was discharged after 7 days with INR 3.0 for two consecutive days. The patient was asymptomatic with stable INR in three- and six-month follow-up visits. Transthoracic ultrasound demonstrated normally functioning mechanical AV. CLINICAL DISCUSSION: Accurate and timely diagnosis of stuck mechanical AV requires high suspicion and timely diagnostic aids. CONCLUSION: Full recovery can be achieved after one cycle of ultraslow thrombolytic therapy. Further supportive data are still needed before recommending thrombolytic therapy as a successful alternative to surgery in COVID-19 patients.
ABSTRACT
The incidence of mechanical valve thrombosis (MVT) is around 0.4 per 100 patient-years. Mitral valve thrombosis has a higher incidence than aortic valve thrombosis with a nearly 5-fold increase. Various factors contribute to MVT. The most common cause of valve thrombosis is poor adherence/disruption of anticoagulation therapy. Low cardiac output is known to increase the risk of prosthetic valve thrombosis. Other factors such as diabetes, hypertension, and other patient comorbidities might also play a role. Decreased flow promotes hypercoagulability. Lower pressure in the left atrium (and higher velocities in the left ventricle) can partially contribute to the higher incidence of mitral MVT versus aortic MVT. The presenting symptoms usually depend on the severity of the valve thrombosis; nonobstructive valve thrombosis patients have progressive dyspnea, signs of heart failure, and systemic embolization with strokes being the most common complication. In this article, we present a case of a middle-aged woman with a history of mitral and aortic mechanical prosthesis who presented with an ST-segment elevation myocardial infarction and pulmonary edema due to mechanical aortic valve prosthesis thrombosis. She had an isolated mechanical aortic valve prosthesis thrombosis with intact mitral valve, which, to the best of our knowledge, has not yet been described. We performed a literature review by searching PubMed and Embase using the keywords "mechanical valve," "thrombosis," "aortic," and "mitral," our search did not show similar cases.