Title : Intraventricular Thrombolysis for LVAD Thrombosis
Abstract:
Intro: This is a case of a patient with previous left ventricular assist device (LVAD) pump thrombosis and prior pump exchange, who developed recurrent pump thrombosis refractory to medical treatment and was not a candidate for a re-do pump exchange.
Case:
A 57 year old woman with stage D non-ischemic cardiomyopathy was admitted with a Heartware LVAD pump thrombosis. Previous pump thrombosis two years prior resulted in a pump exchange. She had a recent history of a large GI bleed and iron deficiency anemia. She was not a candidate for heart transplant due to obesity. Initial treatment consisted of unfractionated heparin, aspirin, and warfarin. Due to suspected haemolysis she required ongoing blood transfusions.
Her LVAD demonstrated worsening function with an acute increase in watts and flows (>10 l/min) despite an INR of 3.9. She was not a candidate for a third pump in view of scarring, RV failure, and the patient's poor response to inotropes indicating defunctionalisation would not be well tolerated.
Given concern for progression of thrombus despite aggressive anticoagulation it was decided to proceed with delivery of thrombolytics directly into the left ventricle (LV) in order to minimise systemic lytic effects. A 6Fr angled pigtail catheter was advanced into the mid-LV cavity and 10mg Alteplase were administered adjacent to the pump.
There was immediate improvement with the pump power quickly decreasing from 8.1 watts to 4.4, then to 3.5. There were no complications from the procedure.
This change lasted until the following day, when there were repeat power surges (>5 watts) and flow speeds (>10lpm), consistent with recurrent pump thrombosis despite an INR of 4.4. She continued to require multiple transfusion of blood products.
In view of the short-lived response to intraventricular thrombolysis, no surgical options, and worsening hemodynamics, the patient ultimately decided to transition to hospice care with palliative inotropy.
Discussion:
LVADs, while an important advanced therapy for advanced heart failure, can develop thrombosis, even with optimal anticoagulation. While pump exchange can be done, the risk may be prohibitive. Therefore, in a select subset of patients, intraventricular thrombolysis may be considered. Our case showed an immediate improvement in pump flow speed and power, but cautions us that results may be temporary. Ultimately, this therapy may be considered in a select series of patients who fail to respond to aggressive anticoagulation and are at high risk for bleeding with the use of systemic thrombolysis.
