Outcomes Of Total Artificial Heart Placement - The Learning Curve From A Single-Center Experience

Abstract

<h3>Introduction</h3> Total artificial heart (TAH) placement is performed for patients with end-stage biventricular heart failure. TAH placement is often utilized as a bridge to heart transplantation (HT). Identifying risk factors for poor outcomes following TAH placement is necessary to select ideal candidates who may benefit from TAH placement as a bridge to HT. <h3>Hypothesis</h3> Advanced age, renal insufficiency (RI), and INTERMACS (IM) profile 1 at the time of TAH placement are poor prognostic factors for six-month survival (SMS) and bridge to HT in patients with end-stage biventricular heart failure. <h3>Methods</h3> In a single-center retrospective analysis between 2012 and 2019, 91 heart failure patients who underwent TAH placement were identified. Patient demographics including age, RI, and IM profile at the time of TAH placement were assessed. Patients were divided into four age quartiles (less than age 35 [quartile 1], age 35 to 49 [quartile 2], age 50 to 64 [quartile 3], and age 65 or greater [quartile 4]). SMS, HT, and heart-kidney transplantation (HKT) rates were compared among the age quartiles and demographic factors. <h3>Results</h3> Among the 91 patients who underwent TAH placement, 59 patients survived and 32 patients did not survive six months following TAH placement. Patients in age quartile 1 had a SMS rate of 91.7% compared to 59.5% in age quartile 3 (p=0.04) and 40% in age quartile 4 (p=0.009). SMS rates decreased with increasing age quartile with rates of 91.7%, 66.7%, 59.5%, and 40%, respectively (p=0.07). IM profile 1 patients had a SMS rate of 58.3% compared to 72.1% in IM profile ≥ 2 patients (p=0.03). Patients in age quartile 4 who were also IM profile 1 had a SMS rate of 0% compared to 100% in age quartile 4 patients who were IM profile ≥ 2 (p=0.001). Patients with RI at the time of TAH placement had a SMS rate of 60% compared to 74.2% in patients without RI (p=0.17). A total of 54 patients underwent HT including 15 patients undergoing HKT. Patients in age quartile 1 underwent HT in 83.3% of cases compared to 30% in age quartile 4 patients (p=0.01). No patients in age quartile 4 who were IM profile 1 underwent HT. IM profile 1 patients underwent HT in 52.1% of cases compared to 67.4% in IM profile ≥ 2 patients (p=0.13). Patients with RI underwent HT in 51.7% of cases compared to 74.2% in patients without RI (p=0.03). <h3>Conclusions</h3> In this single-center study, advanced age was associated with increased six-month mortality and decreased rate of HT following TAH placement. IM profile 1 was also associated with increased six-month mortality after TAH placement, but not decreased rate of HT. When combined with IM profile 1, age ≥ 65 was found to be a significant risk factor for increased six-month mortality following TAH placement and unsuccessful TAH bridge to HT. RI at the time of TAH placement was associated with decreased rate of TAH bridge to HT, but not increased six-month mortality. Larger studies are needed to further assess the effects of these risk factors on TAH placement outcomes.