Title
Breaking the Closed Circuit: Rescue LAVA-ECMO in Mixed Ischemic–Valvular Cardiogenic Shock
Introduction
We describe a case of refractory cardiogenic shock in which veno-arterial extracorporeal membrane oxygenation (VA-ECMO) required rescue left atrial decompression via left atrial veno-arterial extracorporeal membrane oxygenation (LAVA-ECMO) due to a closed left-heart circuit driven by severe ischemic injury, marked left ventricular hypertrophy, and bioprosthetic aortic valve thrombosis.
Clinical Case
A 62 yo M with bioprosthetic AVR presented following a witnessed out-of-hospital arrest. ACLS was initiated in the field and continued in the ED. Pertinent laboratory values included high sensitivity troponin 211 ng/L with 1-hour repeat rise to 3472 ng/L, NT-proBNP 682 pg/mL. ECMO team was activated for peripheral VA ECMO cannulation.
Patient was taken emergently for LHC and RHC. A large thrombus was seen in the left main artery and later migrated to the left circumflex artery with TIMI 3 flow. 99% stenosis of the RCA was treated with PCI of the ostial to proximal RCA with 20 mm Synergy DES, post-dilated with a 4.0 mm noncompliant balloon. RHC pressures obtained revealed AO 42/42 (42), LV 59/58 (58), and PA 38/37 (37). Intraoperative TEE was notable for biventricular systolic failure with absent native ventricular ejection, absent opening of bioprosthetic valve, moderate to severe MR and TR, bi-atrial enlargement, and akinetic LV with near complete decompression on VA-ECMO.
Limited TTE obtained approximately 12 hours later noted persistent ventricular standstill, absent opening of aortic valve, severely dilated RV, and marked concentric LV hypertrophy. Patient continued to require full VA ECMO support indicated by absence of arterial pulsatility, prompting emergent OR for LV venting. TEE identified thrombosis of the bioprosthetic aortic valve, worsening dilation of LA, and developing LV thrombus. Decision was made to proceed with LAVA ECMO. Transseptal puncture using the Baylis transseptal system was performed followed by atrial septostomy using 8 x 20 mm mustang balloon. LA venting ECMO catheter was placed with a 21 French 69.9 cm biomedicus venous vent with subsequent connection to ECMO circuit, effectively transitioning to LAVA ECMO. TEE on LAVA ECMO showed immediate improvement in right atrial distension and appropriate tricuspid opening and closing.
Patient was transferred to a tertiary care center for advanced durable mechanical circulatory support and transplant evaluation. He was ultimately extubated 48 hours after transfer with decreasing vasopressor support. Clinical course was complicated by re-intubation within 24 hours in the setting of developing ARDS. TTE was obtained approximately 1 week after LAVA-ECMO initiation was notable for mild MR and TR, normal functioning bioprosthetic aortic valve, and improvement in LV systolic function 15-19%.
Discussion
Direct LA decompression is an effective strategy to unload the LV when direct LV venting is contraindicated—such as in valve thrombosis, as seen in this patient. LAVA-ECMO is a viable salvage strategy for LA decompression in VA-ECMO patients, thereby breaking the closed-loop circuit. Early recognition of inadequate LV unloading and timely implementation of this strategy are critical, as it may serve as a bridge to advanced therapies and a temporizing measure when definitive options are not immediately available.