Title
Regurgitation, Reperfusion, Rescue: ECMO in the Setting of Aortic Valve Catastrophe
Introduction
Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) offers full cardiopulmonary support and is often a critical intervention in cases of cardiogenic shock. However, its associated increase in afterload can significantly worsen left ventricular performance, particularly in patients with underlying severe aortic regurgitation (AR). In such scenarios, strategies that incorporate active left ventricular unloading such as left atrial veno-arterial ECMO (LAVA-ECMO) offer hemodynamic benefits and should be considered as part of the management approach.
Clinical Case
A 76-year-old white male with a past medical history significant for aortic valve replacement in 2016 with a 23-mm St. Jude bioprosthetic valve due to severe aortic stenosis, atrial fibrillation, heart failure with preserved ejection fraction, chronic kidney disease stage 3b, obstructive sleep apnea, and peripheral vascular disease presented to an outside institution with acute onset dyspnea. Workup revealed anasarca, high oxygen requirements, significant transaminitis, and acute kidney injury, all of which were concerning for developing shock. Electrocardiogram did not show acute ST-T segment changes. A transthoracic echocardiogram (TTE) showed a newly depressed left ventricular ejection fraction and significant deterioration of the bioprosthetic valve causing severe AR. He was immediately transferred to our facility for escalation of care. Urgent right heart catheterization revealed elevated right and left heart filling pressures (RA 28 mmHg and PCWP 35 mmHg, respectively) and a cardiac index of 1.8 L/min/m
2. Our patient continued to deteriorate with escalating inotropic and pressor support. A multidisciplinary shock call was initiated to discuss further steps for the patient. He was deemed an inappropriate surgical candidate given his age, acute on chronic kidney injury, and existing sleep apnea. Decision was made to proceed with LAVA-ECMO as a bridge to valve-in-valve (ViV) transcatheter aortic valve replacement (TAVR). He was subsequently taken to the catheterization lab and underwent cannulation under transesophageal echocardiogram (TEE) guidance. Venous access was obtained through the right femoral vein approach and after appropriate transseptal puncture, the venous cannula was advanced appropriately to allow for biatrial drainage. Arterial access was obtained though the left femoral artery approach, and the arterial cannula was advanced after up-sizing to the appropriately sized sheath. Additionally, a left femoral antegrade arterial catheter was attached to the arterial cannula, and flow into the antegrade catheter was confirmed. Inotropic and pressor support was quickly weaned and repeat invasive hemodynamics shortly after cannulation showed significant improvement in right and left heart filling pressures (RA 9 mmHg and PCWP 20 mmHg, respectively). Over the next 24 hours, patient’s hemodynamics continued to improve and he successfully underwent a VIV TAVR with a 23-mm Sapien Ultra. Repeat TEE demonstrated a well-positioned bioprosthetic valve with a mean gradient of 12 mmHg and no evidence of paravalvular leak. Patient was eventually discharged home from this hospitalization.
Discussion
In the context of cardiogenic shock secondary to severe AR, this case demonstrates how LAVA-ECMO can provide critical circulatory support while mitigating the adverse effects of afterload-related ventricular distension that can occur in this population with VA-ECMO.