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Ventura PA, Alharethi R, Budge D, Reid BB, Horne BD, Mason NO, Stoker S, Caine WT, Rasmusson B, Doty J, Clayson SE, Kfoury AG. Differential impact on post-transplant outcomes between pulsatile- and continuous-flow left ventricular assist devices. Clin Transplant 2011: 25: E390-E395. © 2011 John Wiley & Sons A/S. Abstract: Background: The HeartMate II (HMII) left ventricular assist device (LVAD) has proven reliable and durable and has become the preferred choice for bridge to transplant therapy (BTT) when compared with the pulsatile HeartMate XVE (XVE). In this study, we compared the post-transplant (PTx) outcomes between XVE and HMII using a large national data registry. Methods: The Organ Procurement and Transplantation Network (OPTN)/United Network for Organ Sharing (UNOS) Thoracic Registry database was queried for all patients implanted with either an XVE or an HMII as BTT during 2004-2009. Statistical analysis between XVE and HMII were performed using Kaplan-Meier survival analysis and Cox regression analyses. Results: A total of 673 patients were implanted with the XVE and 484 with HMII. When adjusted for age, gender, ethnicity, intra-aortic balloon pump, ventilator, inotropes, dialysis, body mass index, creatinine, bilirubin, transfusion, pulmonary capillary wedge, and pulmonary arterial pressures, the HMII had similar one- and three-yr survival (hazard ratio = 0.95, CI = 0.64, 1.42) and rejection-free survival PTx compared to XVE. The XVE group had more early incidences of allograft rejection (AR) and hospitalization for infection (HI). Conclusions: Compared to XVE, patients with HMII have similar one- and three-yr survival after heart transplantation with less risk of early graft rejection and significant infection. With a strong shift toward use of continuous-flow LVADs, PTx outcomes are expected to continue to improve. [ABSTRACT FROM AUTHOR]

Background: Thrombus formation on or near the aortic valve has been reported in HeartMate II (Thoratec, Pleasanton, CA) left ventricular assist device (LVAD) patients whose aortic valves do not open. With an akinetic valve, thrombogenesis is more likely. Thrombus formation may lead to neurologic events, placing the patient at greater risk. Aortic valve stenosis and/or regurgitation have also been observed with akinetic aortic valves. Assessing aortic valve opening is crucial when optimizing rotations per minute (rpm) to minimize embolic risk and aortic valve stenosis but presently relies solely on echocardiography, intermittent decreases in rpms to force aortic valve opening, and monitoring of pulse pressure. We hypothesized the electrical current waveforms of the HeartMate II would reveal whether the aortic valve was opening due to pressure changes in the left ventricle to allow for continuous monitoring and control of aortic valve opening ratios. Methods: Electrical HeartMate II current waveforms of patients from 2008 to 2009 that were recorded at the time of echocardiograph procedures were analyzed using a modified Karhunen-Loève transformation with a training set of electrical waveforms from 8,860 HeartMate II electrical current recordings from 2001 to 2009. Results: The study included 6 patients. The electrical current magnitude of the projection of the electrical current waveforms onto the training set''s eigenvectors was statistically significantly greater in 4 of the 6 patients when the aortic valve was closed, confirmed by echocardiography. The 2 patients who did not have a large increase in the magnitude had mild aortic valve regurgitation. Conclusion: Electrical current analysis for rotary non-pulsatile pumps is a means to develop a physiologic feedback algorithm for an auto-mode, which currently does not exist. Constant regulation and optimization of rotary non-pulsatile LVADs would minimize patients'' risk for neurologic events and aortic valve stenosis. [Copyright &y& Elsevier]

Left ventricular assist device (LVAD) implantation before heart transplantation has been associated with formation of antibodies directed against human leukocyte antigens (HLA), often referred to as sensitization. This study investigated whether prior sensitization or LVAD type affected the degree of post-implantation sensitization. The records of consecutive HeartMate (HM) I and HM II LVAD patients were reviewed. Panel reactive antibody (PRA) was assessed before LVAD implantation and biweekly thereafter. Sensitization was defined as PRA > 10%, and high-degree sensitization was defined as PRA > 90%. An HM LVAD was implanted in 64 patients, and 11 received a HM II LVAD as a bridge to transplant. Ten HM I patients (16%) were sensitized before LVAD implantation (HM I-S), and 54 (84%) were not (HM I-Non-S). Nine HM I-S patients (90%) became highly sensitized (PRA > 90%) compared with 9 HM I-Non-S patients (16.7%; p < 0.001). The PRA remained elevated (> 90%) in 8 of the 9 (88.9%) highly sensitized HM I-S patients vs 5 of the 9 (55.6%) HM I-Non-S highly sensitized patients. The PRA levels in the rest of the HM I-S highly sensitized patients declined from 93% ± 4% to 55% ± 15% (p = 0.01). Among the 11 HM II patients, 1 (9%) was sensitized before LVAD implantation (PRA, 40%) and the PRA moderately increased to 80%. No other HM II patient became sensitized after implantation. Thus, 1 of 11 (9%) HM II patients became sensitized compared with 29 of 64 (45%) HM I patients (p = 0.04). Pre-sensitized patients are at higher risk for becoming and remaining highly HLA-allosensitized after LVAD implantation. The HeartMate II LVAD appears to cause less sensitization than HeartMate I. [Copyright &y& Elsevier]