Current left ventricular assist devices (LVADs) are set to a fixed rpm and are unable to adjust to physiological demands irrespective of preload or afterload. Autonomous control of LVADs has the potential to reduce septal shift, preserve right ventricle function, and meet physiological demands. A highly innovative resonantly coupled regimen is presented which can achieve this goal. We introduce sensors based on a highly sensitive relationship between transmission coefficient and spatial separation in a resonantly coupled regimen. This relationship represents a polynomial regression. A regimen of an apical sensor and multiple outflow sensors is investigated. A range of separations varying from 50-200 mm was systematically investigated. These ranges consider anatomical & physiological variation(s) in cardiac chamber size. Validation was obtained in porcine heart preparation.The polynomial regression model predicted distance between the sensors with a mean absolute percentage error of 0.77%, 1.07%, and 5.75% for the three putative positions of the outflow sensors and apical sensor when compared with experimental results. A high degree of accuracy (95%) between the predicted and observed distance was obtained. Continuous measurements were done over 90 days to examine drift, with no statistically detectable change in measurements over million sampling cycles.We have demonstrated a reliable sensor methodology without drift for assessing ventricular chamber size in an LVAD setup. This has the potential to allow autonomous control of LVAD based on ventricular chamber size to address some of the adverse events.

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Introduction:The timeliness of initiating LVAD support has been a subject of debate; this study aims to assess the impact of preoperative multiorgan dysfunction (pMOD) on 6-month and 24-month all-cause mortality LVAD outcomes. Methods: We analyzed the records of patients who received LVAD therapy at a single university hospital between May 2011 and March 2019. pMOD was defined as the presence of heart failure (HF) and at least one of thrombocytopenia (platelets count <150,000/uL); hyperbilirubinemia (serum total bilirubin ≥1.2mg/dL); or AKI (creatinine rise to 1.5 times the baseline). The Records with missing exposure and outcome variables were excluded (n=30), and the final sample size was divided into two groups based on the presence or absence of pMOD. KM survival plot was computed for each group and compared using log-rank statistics. Univariate and multivariate regression models were used to assess the association between pMOD and 6-month and 24-month all-cause mortality. Result: 149 cases of LVAD implantation were included in the final analysis; 90 (60.4%) met the criteria for pMOD, among which 55 (61.1%) had only one organ dysfunction in addition to HF, and 35 (38.9%) had two or more. Adjusting for age, sex, history of CKD, history of diabetes, and MELD score, pMOD is independently associated with three times higher risk of 6-month postoperative mortality when compared with those without pMOD (Adjusted HR (95%CI) = 2.97 (1.48 -5.98); p=0.002). Dysfunction in 2 or more organs, in addition to HF, is associated with two times higher risk of 24-month mortality when compared with those without MOD (Adjusted HR (95%CI) = 2.09 (1.21 -3.63); p=0.009). Conclusion: Preoperative multiorgan dysfunction is a marker of impaired circulation. This has a significant short-and long-term impact on LVAD implantation.

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