Clinical Electrophysiology -> Atrial Fibrillation & Atrial Flutter: -> Left Atrial Appendage Closure D-PO02 - Poster Session II (ID 47) Poster

D-PO02-207 - Inotrope Use To Distinguish Between Dense Spontaneous Echo Contrast Versus Thrombus In The Left Atrial Appendage (ID 255)


Background: Left atrial appendage closure (LAAC) has emerged as a viable alternative to oral anticoagulation (OAC) for stroke prevention in patients with atrial fibrillation (AF) who are poor candidates for long term OAC. During transesophageal echocardiographic (TEE) imaging of the left atrial appendage (LAA), dense spontaneous echo contrast (SEC) is concerning for thrombus and may result in delayed or cancelled therapy. Thus, delineating between dense SEC and LAA thrombus would be valuable in optimizing treatment. We hypothesized that dense SEC, but not thrombus, would clear with increased cardiac output induced by isoproterenol or dobutamine.
Objective: To evaluate the utility of isoproterenol and dobutamine in distinguishing between dense SEC and LAA thrombus.
Methods: Across 2 healthcare systems, patients presenting for LAAC were identified as having dense SEC if it remained nearly stationary for > 3 cardiac cycles on baseline TEE. Patients received either isoproterenol at 2-8 mcg/min, or dobutamine at 5-20 mcg/kg/min. Drug doses were escalated every 3 minutes and repeat imaging was performed. Drug infusion was continued until SEC cleared, or 12 minutes of drug infusion. If SEC cleared, LAAC proceeded as planned. If not, the procedure was cancelled. Peri-procedure complications were defined as any adverse event occurring within 7 days of the procedure.
Results: The patient cohort (n=16) received either isoproterenol (n=12) or dobutamine (n=4). Follow up ranged between 2-24 months post-LAAC. LAA morphologies were a mix of cauliflower, chicken wing, windsock, and cactus. The mean CHA2DS2-VASc score was 5.19. The mean LVEF was 51.3%. Dense SEC cleared in 14 of 16 pts (87.5%) - 11 of 12 with isoproterenol, and 3 of 4 with dobutamine. No patient suffered a periprocedural complication.
Conclusion: When a patient planned for a LAAC procedure is identified by TEE imaging as having dense SEC, the LAA can typically be “cleared” as not harboring a thrombus by infusion of inotropic agents. No complications were observed in this case series. The safety of this approach will need to be confirmed in a larger trial.