Assessing Cardiac Recovery for Decommissioning of LVAD Support: Structure versus Function

Abstract

<h3>Introduction</h3> Recovery of left ventricular (LV) function during LVAD support occurs in only 1-3% of patients. Assessment for recovery and LVAD removal is desirable given the risks of infection, stroke, and device malfunction. This case of a patient with an LVAD, with recovered LV systolic function but abnormal exercise hemodynamics, illustrates the potential utility of right heart catheterization studies for clinical decisions. <h3>Case Report</h3> A 35-year-old man presented with cardiogenic shock after a late-presentation ST elevation myocardial infarction, requiring short-term veno-arterial extracorporeal membrane oxygenation post-angioplasty. Then, a HeartMate II LVAD was inserted. Four months after implantation, the patient was well (NYHA I). Serial echocardiography demonstrated recovery of LVEF to 50-55% by 7 months. Repeated hemodynamic assessments were performed over 11 months. Hemodynamics were recorded at supine rest with baseline LVAD speed, with speed reduced to the equivalent of unsupported (8000 rpm) and then during cycle ergometer exercise at a constant work rate (Table). Between baseline and unsupported speeds, minimal change in the mixed venous O2 saturation and smaller increases in mean pulmonary arterial wedge pressure (mPAWP) and mean pulmonary artery pressures (mPAP) were noted during the 3rd and 4th studies. However, during exercise, the patient displayed persistently limited increases in cardiac output (CO) and the relationship between PAWP and CO (∆PAWP/∆CO) was persistently elevated above 2 mmHg/L/min. As such, the patient was listed for transplant rather than explanted. <h3>Summary</h3> Although echocardiographic imaging showed recovery of LV systolic function, exercise at unsupported speed was associated with abnormal ∆PAWP/∆CO, prompting concern of recurrent symptomatic heart failure if the LVAD was explanted. This case illustrates ongoing efforts to evaluate appropriate structural and functional markers of myocardial recovery to support decisions regarding LVAD explantation.