Abstract 4363464: Fibrinolytic Debulking of a Large Left Ventricular Thrombus Prior to Emergent Valve-in-Valve Transcatheter Aortic Valve Replacement in the Setting of Critical Bioprosthetic Aortic Stenosis and Cardiogenic Shock

Description of Case: Left ventricular (LV) thrombus is generally a contraindication to transcatheter aortic valve replacement (TAVR) due to thromboembolic risk. However, non-surgical patients with valvular cardiogenic shock (CS) require urgent valve correction for meaningful recovery. Prior valve prostheses and/or the presence of LV thrombus complicates management, often barring intervention. We present the novel use of tissue plasminogen activator (tPA) as bridge to valve-in-valve (ViV) TAVR in a 58-year-old woman with critical bioprosthetic stenosis and valvular CS complicated by large LV thrombus. A 58 year old female with a history of surgical bioprosthetic aortic valve replacement presented emergently with rapidly progressive dyspnea. Echocardiogram revealed critical low-flow, high gradient aortic stenosis (peak velocity 4.5m/s, mean gradient 51 mmHg) secondary to bioprosthesis degeneration, a newly reduced ejection fraction (15-20%), and a 2.8x2.6cm mobile LV thrombus. She subsequently developed valvular CS requiring dual ionotropic support. Surgical risk was prohibitive as she was not an advanced heart failure therapy candidate based on multi-disciplinary discussion. Medical debulking of the thrombus was planned following a novel protocol from an ongoing clinical trial. Pulsed 6-hour infusions of 25 mg tPA were administered with serial echocardiography demonstrating step-wise reduction in thrombus dimensions. Valve selection was assisted by DASI ® computational modeling. Dual SENTINEL ® devices were placed and the patient underwent ViV-TAVR (23mm Evolut FX+ ®) with ICE guidance of the LV wire to minimize instrumentation of the thrombus. Hemodynamic and echocardiographic results were excellent. The patient was rapidly liberated from ionotropes and has no neurological sequelae to date. Discussion: To date there are no guidelines or large studies to inform the use of systemic fibrinolysis as a bridge to structural cardiology intervention in patients with LV thrombi. There are case reports of ICE guidance during ViV-TAVR with LV thrombus and use of systemic fibrinolysis for treatment of aortic valve thrombosis, however outcomes are mixed. To our knowledge, there is no report of tPA bridge to successful ViV-TAVR in acute valvular CS complicated by LV thrombus. More data are needed.