P6: Mechanical Circulatory Support for Acute Severe Aortic Regurgitation and Cardiogenic Shock

Abstract

Background: We describe a case of cardiogenic and septic shock complicated by acute severe aortic regurgitation (AR) temporized by left-atrial-venoarterial (LA-VA) ECMO. Patient Presentation & Results: A 42-year-old female with end stage renal disease, type 2 diabetes, and osteomyelitis of the right foot on outpatient intravenous antibiotics presented with fevers. On initial evaluation, transthoracic echocardiogram (TTE) demonstrated normal left ventricular (LV) function with no valvular abnormalities and methicillin resistant staphylococcus aureus was identified in blood cultures. Despite several days of antibiotic treatment, the patient decompensated requiring intubation and vasopressors. Vitals were notable for a blood pressure of 80/10 mmHg. A repeat TTE demonstrated severe AR with leaflet perforation consistent with endocarditis. The patient suffered cardiac arrest and after return of spontaneous circulation, she was taken to the catheterization laboratory for mechanical circulatory support. Via the right femoral vein, initial transeptal puncture revealed a LA pressure of 35mmHg with V waves to 45mmHg. A 21Fr transeptal drainage cannula was placed in the LA with a 17Fr return cannula in the left common femoral artery for extracorporeal support with a Tandem Heart (Livanova) system. Right heart catheterization on 5Lpm of support along with epinephrine, levophed, dopamine and vasopressin were as follows: RA 13mmHg, PA 50/22 mmHg (mean 35mmHg, PA sat 53.5%) and CO/CI of 4.49/2.27 L/min/m2. Overnight the transeptal cannula was dislodged and an oxygenator was rapidly spliced converting the system to VA ECMO. On this configuration she underwent bedside guillotine amputation of the right foot and was then taken back to the catheterization laboratory where a second drainage cannula was placed into the LA, this time from the left femoral vein. A Y-connector was used to allow simultaneous inflow from both the displaced right atrial cannula (which was partially pulled into the IVC) and the new LA cannula into the pump (Picture 1). The patient underwent successful surgical aortic valve replacement (SAVR) with a 23mm Edwards Inspirus bioprosthesis. She was successfully weaned off circulatory support and ultimately discharged. Conclusion: Severe AR has been known to be a major contraindication for VA ECMO. In addition to hemodynamic instability and rapidly rising LA pressures with subsequent pulmonary edema, a noncompetent aortic valve makes MCS a unique challenge in cases of acute severe AR. In our case, normal LV function and unloading of the LA allowed for appropriate native LV output despite increased afterload from femoral artery return in the setting of severe AR. LA-VA ECMO created a window of hemodynamic stability to allow for amputation of an infected foot and successful SAVR.