Ensuring a Post-COVID Economic Agenda Tackles Global Biodiversity Loss.

The COVID-19 pandemic has caused dramatic and unprecedented impacts on both global health and economies. Many governments are now proposing recovery packages to get back to normal, but the 2019 Intergovernmental Science-Policy Platform for Biodiversity and Ecosystem Services Global Assessment indicated that business as usual has created widespread ecosystem degradation. Therefore, a post-COVID world needs to tackle the economic drivers that create ecological disruptions. In this perspective, we discuss a number of tools across a range of actors for both short-term stimulus measures and longer-term revamping of global, national, and local economies that take biodiversity into account. These include measures to shift away from activities that damage biodiversity and toward those supporting ecosystem resilience, including through incentives, regulations, fiscal policy, and employment programs. By treating the crisis as an opportunity to reset the global economy, we have a chance to reverse decades of biodiversity and ecosystem losses.

Predictors of severe right ventricular failure after implantable left ventricular assist device insertion: analysis of 245 patients.

BACKGROUND: Insertion of an implantable left ventricular assist device (LVAD) complicated by early right ventricular (RV) failure has a poor prognosis and is largely unpredictable. Prediction of RV failure after LVAD placement would lead to more precise patient selection and optimal device selection. METHODS AND RESULTS: We reviewed data from 245 patients (mean age, 54+/-11 years; 85% male) with 189 HeartMate (77%) and 56 Novacor (23%) LVADs. Ischemic cardiomyopathy predominated (65%), and 29% had dilated cardiomyopathy. Overall, RV assist device (RVAD) support was required after LVAD insertion for 23 patients (9%). We compared clinical and hemodynamic parameters before LVAD insertion between RVAD (n=23) and No-RVAD patients (n=222) to determine preoperative risk factors for severe RV failure. By univariate analysis, female gender, small body surface area, nonischemic etiology, preoperative mechanical ventilation, circulatory support before LVAD insertion, low mean and diastolic pulmonary artery pressures (PAPs), low RV stroke work (RVSW), and low RVSW index (RVSWI) were significantly associated with RVAD use. Elevated PAP and pulmonary vascular resistance were not risk factors. Risk factors by multivariable logistic regression were preoperative circulatory support (odds ratio [OR], 5.3), female gender (OR, 4.5), and nonischemic etiology (OR, 3.3). CONCLUSIONS: The need for circulatory support, female gender, and nonischemic etiology were the most significant predictors for RVAD use after LVAD insertion. Regarding hemodynamics, low PAP and low RVSWI, reflecting low RV contractility, were important parameters. This information may lead to better patient selection for isolated LVAD implantation.

Device based left ventricular shape change: validation of conductance technology in shape changed hearts.

We have reported that device based left ventricular (LV) shape change, accomplished by Myosplint, improved LV systolic function by three-dimensional echocardiography (3-D echo). However, evaluation of this device using the pressure-volume relationship is still important. This study was conducted to validate the use of conductance technology for this evaluation in shape-changed hearts. An ex vivo study using excised ovine hearts (n = 11) and an in vivo study using a canine pacing-induced heart failure model (n = 11) were performed. Three Myosplints were implanted. Before and after the shape changes, volumes measured by a conductance catheter were compared with volumes measured by the amount of saline in the ex vivo study or by 3-D echo in the in vivo study. The conductance volumes were linearly correlated with the saline volumes (r2 = 0.961+/-0.046; p < 0.0001) in the ex vivo study and with 3-D echo volumes (r2 = 0.757+/-0.220; p < 0.0001) in the in vivo study. The conductance volumes were linearly correlated with LV volumes even in the shape-changed hearts. This technology can be used to evaluate pressure-volume loops in the shape-changed hearts as long as the conductance volume is calibrated by a reliable method.

In vivo studies of the MagScrew total artificial heart in calves.

The purpose of this study was to evaluate the in vivo pump performance of our total artificial heart (TAH), the "MagScrew TAH." The TAH consists of a blood pump and control logic developed at the Cleveland Clinic and the MagScrew actuator and electronic control system developed by Foster-Miller Technologies, Inc. (Albany, NY). MagScrew TAH implantation was performed in two calves. Study durations were 50 and 5 days. The causes of termination were prosthetic valve endocarditis in one case and cable failure in the other. Mean left pump flow ranged from 8.0 to 9.7 L/min, with left atrial pressure of 3.0 to 16.0 mm Hg. Preload sensitivity of the MagScrew TAH demonstrated a Frank-Starling response to preload in automatic mode. The relationship between right and left atrial pressure was well balanced. Mean arterial pressure and mean pulmonary artery pressure were maintained within physiologic ranges over study duration. There were no signs of bleeding, hemolysis, or organ failure. The MagScrew TAH showed physiologic pump performance, and hemodynamics were well maintained without any organ failure. Further development testing will bring the MagScrew TAH to the point of preclinical readiness testing.

Cleveland clinic CorAide blood pump circulatory support without anticoagulation.

The Cleveland Clinic CorAide left ventricular assist system consists of a permanently implantable centrifugal pump in which the rotating assembly is completely suspended and noncontacting. A series of chronic animal in vivo studies were conducted to evaluate the biologic effects of CorAide circulatory support without the use of anticoagulation therapy. The CorAide pump was implanted in six calves (five calves for 21 to 32 days and one calf for 95 days). The first five calves received intravenous heparin during the early postoperative periods (2-7 days). Heparin administration was then discontinued and no other anticoagulant drugs were used for the duration of the experiments. The last calf did not receive any anticoagulant except for a bolus dose of heparin (200 U/kg) during surgery. Hemodynamics were stable in all six calves, with a mean pump flow of 5.6+/-1.2 L/min and mean arterial pressure of 100+/-4 mm Hg. The blood pump surfaces were clean of thrombus in all six calves. Significant findings at autopsy were limited to one case of renal infarction. There was no incidence of mechanical failure, bleeding, or device infection. The CorAide pump can be safely run with minimal or no anticoagulant therapy.

Chronic evaluation of the Cleveland Clinic CorAide left ventricular assist system in calves.

The Cleveland Clinic CorAide left ventricular assist system is based on a third-generation, implantable, centrifugal pump in which a rotating assembly is suspended fully. To evaluate chronic in vivo system performance and biocompatibility, the CorAide blood pump was implanted in 18 calves for either 1 month or 3 months. Hemodynamics were stable in all calves with a mean pump flow of 5.9 +/- 1.2 L/min and a mean systemic arterial pressure of 98 +/- 5 mm Hg. There were no incidences of bleeding, organ dysfunction, or mechanical failure in any of the 18 calves. Hemolysis occurred in only 1 calf due to outflow graft stenosis. Thrombus inside the pump, seen in 4 of the first 6 cases, was totally eliminated by a final redesign in the remaining cases, including the last 6 implants conducted without anticoagulation therapy. The CorAide blood pump demonstrated good biocompatibility and reliable, effective system performance.