Pressure-volume Area Research Articles

SIMULASI LENSA GRATING TERHADAP EFISIENSI DIFRAKSI GRATING PADA SISTEM PEMISAH CAHAYA SPEKTRAL CONCENTRATED PHOTOVOLTAIC/THERMAL

A spectral beam splitting concentrated photovoltaic/thermal (SBS CPVT) system is a new technology in PV areas . In order to split the sunlight, the grating lens is used in this study. The tool of this study is G-Solver software which simulates the diffraction efficiency of visible light and infrared light of the blazed and binary grating lens. The aim of this paper is to analyze the potential of the diffraction efficiency of grating lens when applied in SBS CPVT. The result show that binary grating, the highest diffraction efficiency for the visible light is also almost unchanged for the aspect ratio from 1.4 to 2, but the peak wavelength shift from around 360 nm to 510 nm, while, for IR light, the diffraction efficiency decrease from aspect ratio 1.4 to 2. On the other hand, blazed grating, The highest diffraction efficiency for the visible light is almost unchanged for the aspect ratio from 1.4 to 2, but the peak wavelengths shift from around 350 nm to 500 nm. While IR light, the diffraction efficiency decrease with the aspect ratio 1.4 to 2

Depressed Cardiac Mechanical Energetic Efficiency: A Contributor to Cardiovascular Risk in Common Metabolic Diseases-From Mechanisms to Clinical Applications.

Cardiac mechanical energetic efficiency is the ratio of external work (EW) to the total energy consumption. EW performed by the left ventricle (LV) during a single beat is represented by LV stroke work and may be calculated from the pressure–volume loop area (PVLA), while energy consumption corresponds to myocardial oxygen consumption (MVO2) expressed on a per-beat basis. Classical early human studies estimated total mechanical LV efficiency at 20–30%, whereas the remaining energy is dissipated as heat. Total mechanical efficiency is a joint effect of the efficiency of energy transfer at three sequential stages. The first step, from MVO2 to adenosine triphosphate (ATP), reflects the yield of oxidative phosphorylation (i.e., phosphate-to-oxygen ratio). The second step, from ATP split to pressure–volume area, represents the proportion of the energy liberated during ATP hydrolysis which is converted to total mechanical energy. Total mechanical energy generated per beat—represented by pressure–volume area—consists of EW (corresponding to PVLA) and potential energy, which is needed to develop tension during isovolumic contraction. The efficiency of the third step of energy transfer, i.e., from pressure–volume area to EW, decreases with depressed LV contractility, increased afterload, more concentric LV geometry with diastolic dysfunction and lower LV preload reserve. As practical assessment of LV efficiency poses methodological problems, De Simone et al. proposed a simple surrogate measure of myocardial efficiency, i.e., mechano-energetic efficiency index (MEEi) calculated from LV stroke volume, heart rate and LV mass. In two independent cohorts, including a large group of hypertensive subjects and a population-based cohort (both free of prevalent cardiovascular disease and with preserved ejection fraction), low MEEi independently predicted composite adverse cardiovascular events and incident heart failure. It was hypothesized that the prognostic ability of low MEEi can result from its association with both metabolic and hemodynamic alterations, i.e., metabolic syndrome components, the degree of insulin resistance, concentric LV geometry, LV diastolic and discrete systolic dysfunction. On the one part, an increased reliance of cardiomyocytes on the oxidation of free fatty acids, typical for insulin-resistant states, is associated with both a lower yield of ATP per oxygen molecule and lesser availability of ATP for contraction, which might decrease energetic efficiency of the first and second step of energy transfer from MVO2 to EW. On the other part, concentric LV remodeling and LV dysfunction despite preserved ejection fraction can impair the efficiency of the third energy transfer step. In conclusion, the association of low MEEi with adverse cardiovascular outcome might be related to a multi-step impairment of energy transfer from MVO2 to EW in various clinical settings, including metabolic syndrome, diabetes, hypertension and heart failure. Irrespective of theoretical considerations, MEEi appears an attractive simple tool which couldt improve risk stratification in hypertensive and diabetic patients for primary prevention purposes. Further clinical studies are warranted to estimate the predictive ability of MEEi and its post-treatment changes, especially in patients on novel antidiabetic drugs and subjects with common metabolic diseases and concomitant chronic coronary syndromes, in whom the potential relevance of MEE can be potentiated by myocardial ischemia.

Comparison of Hemodynamic Support by Impella vs. Peripheral Extra-Corporeal Membrane Oxygenation: A Porcine Model of Acute Myocardial Infarction.

Objectives: Several mechanical circulatory assist devices are used to treat critically ill patients requiring hemodynamic support during post-myocardial infarction or cardiogenic shock. However, little guidance is available to choose an appropriate device to match a particular patient's needs. An increased understanding of hemodynamic effects of the pump systems and their impact on myocardial pre-/afterload might help to better understand their behavior in different clinical settings.Methods: This was an open-labeled, randomized acute animal experiment. A model of acute univentricular myocardial injury by temporary balloon occlusion was used. The experiment was carried out in 10 juveniles female Piétrain pigs. The animals were randomized to mechanical hemodynamic support either by peripheral veno-arterial (VA-)ECMO or Impella CP.Results: While both devices were able to provide flows above 3 L/min and maintain sufficient end-organ perfusion, support by Impella resulted in a significantly more pronounced immediate effect on myocardial unloading: At the onset of device support, the remaining native cardiac output was reduced by 23.5 ± 15.3% ECMO vs. 66.2 ± 36.2% (Impella, p = 0.021). Native stroke volume was significantly decreased by Impella support compared to ECMO, indicating less mechanical work being conducted by the Impella-supported hearts despite similar total assisted cardiac output.Conclusions: Peripheral VA-ECMO and the transaortic Impella pump resulted in contrasting hemodynamic fingerprints. Both devices provided sufficient hemodynamic support and reduce left ventricular end-diastolic pressure in the acute setting. Treatment with the Impella device resulted in a more effective volume unloading of the left ventricle. A significant reduction in myocardial oxygen consumption equivalent was achieved by both devices: The Impella device resulted in a left-shift of the pressure-volume loop and a decreased pressure-volume-area (PVA), while VA-ECMO increased PVA but decreased heart rate. These data highlight the importance of specifically targeting heart rate in the management of AMI patients on hemodynamic support.

The investigation of energy production and mushroom yield in greenhouse production based on mono photovoltaic cells effect

The purpose of this study is to present the potentiality of an innovative cooling system and mono passivated emitter rear contact photovoltaic cells (Mono PERC PV) with shading to optimize energy production, the microclimatic conditions and Pleurotus mushrooms (Pleurotus ostreatus)production. The off-grid PV system consisted of 12 modules (6 mono bifacial PERC PV (Mono BPERC PV) modules and 6 Mono PERC PV modules) which provide higher efficiency, absorb more light, and the high performances lead to lower system costs. Three Mono PERC PV panels were installed facing south and at a tilt angle of 30°, covering 20% of the roof area. Each module had a peak power of 365 Wp and an efficiency of 18.8%. The results revealed that the annual generated electric energy by the off-grid PV system was around 6288 kWh/year and it is enough to supply the greenhouse’s energy needs 3164.0 kWh/year. The highest mushroom productivity 1600 g was recorded with the cooling system in the PV area at 1.0 m height treatment. The reduction in solar radiation in the Mono PERC PV area was 31.9%–38.25% higher than that in the control area on clear days. The cooling system ensured that the environmental conditions were suitable for mushroom growth. The optimum temperature and relative humidity for growing Pleurotus mushrooms ranged from 18 °C to 25 °C and 80%–95%, respectively under controlled conditions.

New insights into resting and exertional right ventricular performance in the healthy heart through real-time pressure-volume analysis.

Despite growing interest in right ventricular form and function in diseased states, there is a paucity of data regarding characteristics of right ventricular function - namely contractile and lusitropic reserve, as well as ventricular-arterial coupling, in the healthy heart during rest, as well as submaximal and peak exercise. Pressure-volume analysis of the right ventricle, during invasive cardiopulmonary exercise testing, demonstrates that that the right heart has enormous contractile reserve, with a three- or fourfold increase in all metrics of contractility, as well as myocardial energy production and utilization. The healthy right ventricle also demonstrates marked augmentation in lusitropy, indicating that diastolic filling of the right heart is not passive. Rather, the right ventricle actively contributes to venous return during exercise, along with the muscle pump. Ventricular-arterial coupling is preserved during submaximal and peak exercise in the healthy heart. Knowledge of right ventricular (RV) function has lagged behind that of the left ventricle and historically, the RV has even been referred to as a 'passive conduit' of lesser importance than its left-sided counterpart. Pressure-volume (PV) analysis is the gold standard metric of assessing ventricular performance. We recruited nine healthy sedentary individuals free of any cardiopulmonary disease (42±12years, 78±11kg), who completed invasive cardiopulmonary exercise testing during upright ergometry, while using conductance catheters inserted into the RV to generate real-time PV loops. Data were obtained at rest, two submaximal levels of exercise below ventilatory threshold, to simulate real-world scenarios/activities of daily living, and maximal effort. Breath-by-breath oxygen uptake was determined by indirect calorimetry. During submaximal and peak exercise, there were significant increases in all metrics of systolic function by three- to fourfold, including cardiac output, preload recruitable stroke work, and maximum rate of pressure change in the ventricle (dP/dtmax ), as well as energy utilization as determined by stroke work and pressure-volume area. Similarly, the RV demonstrated a significant, threefold increase in lusitropic reserve throughout exercise. Ventricular-arterial coupling, defined by the quotient of end-systolic elastance and effective arterial elastance, was preserved throughout all stages of exercise. Maximal pressures increased significantly during exercise, while end-diastolic volumes were essentially unchanged. Overall, these findings demonstrate that the healthy RV is not merely a passive conduit, but actively participates in cardiopulmonary performance during exercise by accessing an enormous amount of contractile and lusitropic reserve, ensuring that VA coupling is preserved throughout all stages of exercise.

Dynamic Arterial Elastance as a Ventriculo-Arterial Coupling Index: An Experimental Animal Study.

Dynamic arterial elastance (Eadyn), the ratio between arterial pulse pressure and stroke volume changes during respiration, has been postulated as an index of the coupling between the left ventricle (LV) and the arterial system. We aimed to confirm this hypothesis using the gold-standard for defining LV contractility, afterload, and evaluating ventricular-arterial (VA) coupling and LV efficiency during different loading and contractile experimental conditions. Twelve Yorkshire healthy female pigs submitted to three consecutive stages with two opposite interventions each: changes in afterload (phenylephrine/nitroprusside), preload (bleeding/fluid bolus), and contractility (esmolol/dobutamine). LV pressure-volume data was obtained with a conductance catheter, and arterial pressures were measured via a fluid-filled catheter in the proximal aorta and the radial artery. End-systolic elastance (Ees), a load-independent index of myocardial contractility, was calculated during an inferior vena cava occlusion. Effective arterial elastance (Ea, an index of LV afterload) was calculated as LV end-systolic pressure/stroke volume. VA coupling was defined as the ratio Ea/Ees. LV efficiency (LVeff) was defined as the ratio between stroke work and the LV pressure-volume area. Eadyn was calculated as the ratio between the aortic pulse pressure variation (PPV) and conductance-derived stroke volume variation (SVV). A linear mixed model was used for evaluating the relationship between Ees, Ea, VA coupling, LVeff with Eadyn. Eadyn was inversely related to VA coupling and directly to LVeff. The higher the Eadyn, the higher the LVeff and the lower the VA coupling. Thus, Eadyn, an easily measured parameter at the bedside, may be of clinical relevance for hemodynamic assessment of the unstable patient.

Impact of Concomitant Vasoactive Treatment in Mechanical Left Ventricular Unloading in Profound Cardiogenic Shock

To compare the effect of equipotent dosages of epinephrine, dopamine, norepinephrine, and phenylephrine on left ventricular (LV) work and end-organ perfusion in a porcine model of profound ischemic cardiogenic shock (CS) supported by Impella CP. CS was induced in 10 pigs by stepwise intracoronary injection of microspheres. After CS was induced and Impella CP support initiated, animals were treated in a blinded crossover design with norepinephrine (0.10 µg/kg/min), epinephrine (0.10 µg/kg/min) or dopamine (10 µg/kg/min) for 30 minutes each. Phenylephrine (10 µg/kg/min) was given at the end of the study for 20 minutes. LV work was estimated using a conductance catheter. Main outcome measure was LV work estimated by pressure volume area (PVA) x heart rate. End-organ perfusion was evaluated by mixed venous oxygen saturation (SVO2) from the pulmonary artery and arterial lactate levels. Multilevel mixed-effects linear regression was used to evaluate treatment effect. All vasoactive drugs induced a significant increase in LV work, borderline for norepinephrine by 92.4 (mmHg*mL)*103/min ⦋95%CI(-1.1, 186), p=0.053)⦌. For all catecholamines, stroke work was significantly increased, but unchanged with phenylephrine, which on the other hand caused a significant increase in potential energy by 483 mmHg*mL ⦋95%CI(195, 772), p=0.001)⦌. SVO2 increased significantly with catecholamines and decreased borderline with phenylephrine by -9 %point ⦋95%CI(-19, 0.49), p=0.063)⦌ which also increased arterial lactate levels by 2.4 mmol/L ⦋95%CI(0.89, 3.92), p=0.002)⦌. There was a trend toward lower arterial lactate levels with norepinephrine by -1.53 mmol/L ⦋95%CI(-3.15, 0.09), p=0.064)⦌ CONCLUSION: Catecholamines increased SVO2 but at the expense of increased LV work, least for norepinephrine and highest for dopamine (figure). Isolated vasoconstriction (phenylephrine) caused an increase in LV work, a decrease in SVO2 and increase in arterial lactate levels.

Demand Response Economic Assessment with the Integration of Renewable Energy for Developing Electricity Markets

Electricity disparity in sub-Saharan Africa is a multi-dimensional challenge that has significant implications on the current socio-economic predicament of the region. Strategic implementation of demand response (DR) programs and renewable energy (RE) integration can provide efficient solutions with several benefits such as peak load reduction, grid congestion mitigation, load profile modification, and greenhouse gas emissions reduction. In this research, an incentive and price-based DR programs model using the price elasticity concepts is proposed. Economic analysis of the customer benefit, utility revenue, load factor, and load profile modification are optimally carried out using Freetown (Sierra Leone) peak load demand. The strategic selection index is employed to prioritize relevant DR programs that are techno-economically beneficial for the independent power producers (IPPs) and participating customers. Moreover, optimally designed hybridized grid-connected RE was incorporated using the Genetic Algorithm (GA) to meet the deficit after DR implementation. GA is used to get the optimal solution in terms of the required PV area and the number of BESS to match the net load demand after implementing the DR schemes. The results show credible enhancement in the load profile in terms of peak period reduction as measured using the effective load factor. Moreover, customer benefit and utility revenues are significantly improved using the proposed approach. Furthermore, the inclusion of the hybrid RE supply proves to be an efficient approach to meet the load demand during low peak and valley periods and can also mitigate greenhouse gas emissions.

Impact of concomitant vasoactive treatment and mechanical left ventricular unloading in a porcine model of profound cardiogenic shock

BackgroundConcomitant vasoactive drugs are often required to maintain adequate perfusion pressure in patients with acute myocardial infarction (AMI) and cardiogenic shock (CS) receiving hemodynamic support with an axial flow pump (Impella CP).ObjectiveTo compare the effect of equipotent dosages of epinephrine, dopamine, norepinephrine, and phenylephrine on cardiac work and end-organ perfusion in a porcine model of profound ischemic CS supported with an Impella CP.MethodsCS was induced in 10 pigs by stepwise intracoronary injection of polyvinyl microspheres. Hemodynamic support with Impella CP was initiated followed by blinded crossover to vasoactive treatment with norepinephrine (0.10 μg/kg/min), epinephrine (0.10 μg/kg/min), or dopamine (10 μg/kg/min) for 30 min each. At the end of the study, phenylephrine (10 μg/kg/min) was administered for 20 min. The primary outcome was cardiac workload, a product of pressure-volume area (PVA) and heart rate (HR), measured using the conductance catheter technique. End-organ perfusion was assessed by measuring venous oxygen saturation from the pulmonary artery (SvO2), jugular bulb, and renal vein. Treatment effects were evaluated using multilevel mixed-effects linear regression.ResultsAll catecholamines significantly increased LV stroke work and cardiac work, dopamine to the greatest extend by 341.8 × 103 (mmHg × mL)/min [95% CI (174.1, 509.5), p < 0.0001], and SvO2 significantly improved during all catecholamines. Phenylephrine, a vasoconstrictor, caused a significant increase in cardiac work by 437.8 × 103 (mmHg × mL)/min [95% CI (297.9, 577.6), p < 0.0001] due to increase in potential energy (p = 0.001), but no significant change in LV stroke work. Also, phenylephrine tended to decrease SvO2 (p = 0.063) and increased arterial lactate levels (p = 0.002).ConclusionCatecholamines increased end-organ perfusion at the expense of increased cardiac work, most by dopamine. However, phenylephrine increased cardiac work with no increase in end-organ perfusion.

Real-Time Performance Assessment of Operating Photovoltaic (PV) Systems

A technology called solar energy is a very promising technique, and is considered as the cleanest and the most abundant renewable resource that is naturally available every day. In this paper, a MATLAB environment has been developed to calculate real-time power incidence on a PV system. It takes into account the time, location, PV tilt, and azimuth angles, and weather conditions to estimate incident power. In this paper, one case study is considered at New York State location. It has been applied to a newly installed 8 kW residential system located in Inwood. The solar panels are made up of silicon HIT (Heterojunction with Intrinsic Thin Layer) cells by Panasonic and solar cell rated at 19%. The result shows that the system is performing at its rated efficiency. The calculations involve the determination of direct, diffused and reflected radiation on the panels taking into account the time of the day, location, PV area, and orientations and weather conditions. The cloudiness index may be estimated based on the weather data and included in the calculations. After performing the irradiance calculations, the output power is estimated based on the rated efficiency at its temperature and compared with the generated output power. The real-time assessment of a PV system performance, during the operational time monitors the health of the PV system. The data obtained by this calculator may accompany production data provided to the consumer by the utility company.

P1421 Patients with severe aortic regurgitation showed systolic dysfunction and increased stroke work despite preserved EF; clues for reconsidering optimal time point of surgery

Abstract Background Current guidelines recommend surgery in patients with severe aortic regurgitation (AR) with clinical symptoms or subnormal ejection fraction (EF). Furthermore, surgery should be considered in patients with severe AR, preserved EF and increased left ventricular diameters (LVEDD &amp;gt;70mm, LVESD &amp;gt;50mm). The aim of the study was to investigate LV systolic function as well as mechanical energetics using non-invasive pressure-volume- and strain analysis in patients with severe AR and preserved EF as well as moderately dilated ventricles (LVEDD &amp;lt;70mm). Methods and Results Echocardiographic strain and single beat pressure-volume analyses were performed in patients with severe AR and moderately increased ventricular size (LVEDD &amp;lt; 70mm, EF &amp;gt;50% n = 39) as well as healthy, age-matched controls (n = 20) using echo-derived volume and arm-cuff blood pressure measurements. Load independent parameters of systolic contractile function like end-systolic elastance (Ees) and end-systolic volume at 100mmHg (ESV100) were calculated as well as stroke work ((SW) and total pressure volume area (PVA = SW + potential energy). Patients with AR demonstrated significant depression of systolic function beyond ejection fraction: global longitudinal strain was reduced compared to controls (-16 ±2.5% vs. -21.5 ±2%; p &amp;lt; 0.001). Accordingly load independent parameters of LV contractility like Ees (1.5mmHg/ml ±0.7 vs. 2.25mmHg/ml ±0.7; p &amp;lt; 0.001), ESV100 (65.7ml ±19.4 vs. 42.4ml ±19.8; p &amp;lt; 0.05) were reduced despite comparable ejection fractions (EF: 0.56% ±0.05 vs. 0.60% ±0.07 p = 0,10). End-diastolic volume of AR patients was markedly elevated (236ml ±90 vs. 136ml ±30; p &amp;lt; 0.001), while PVA (20470mmHg x ml ±10400 vs. 11907mmHg x ml ±2877; p &amp;lt; 0.01) and stroke work (13200mmHg x ml ±5700 vs. 7606 mmHG x ml ±2048; p&amp;lt; 0.01) were markedly elevated indicating waste of energy. Conclusion Patients with severe AR and moderately enhanced LV showed depressed values of contractility and waste of energy using more advanced parameters of LV systolic function although EF was preserved. The data may demonstrate that surgery is performed too late in many of those patients and may give clues for reconsidering guidelines to meet the optimal time point of surgery. .

Vasoactive Intestinal Peptide Derived From Liver Mesenchymal Cells Mediates Tight Junction Assembly in Mouse Intrahepatic Bile Ducts.

Formation of intrahepatic bile ducts (IHBDs) proceeds in accordance with their microenvironment. Particularly, mesenchymal cells around portal veins regulate the differentiation and ductular morphogenesis of cholangiocytes in the developing liver; however, further studies are needed to fully understand the arrangement of IHBDs into a continuous hierarchical network. This study aims to clarify the interaction between biliary and liver mesenchymal cells during IHBD formation. To identify candidate factors contributing to this cell–cell interaction, mesenchymal cells were isolated from embryonic day 16.5 matrix metalloproteinase 14 (MMP14)‐deficient (knockout [KO]) mice livers, in which IHBD formation is retarded, and compared with those of the wild type (WT). WT mesenchymal cells significantly facilitated the formation of luminal structures comprised of hepatoblast‐derived cholangiocytes (cholangiocytic cysts), whereas MMP14‐KO mesenchymal cells failed to promote cyst formation. Comprehensive analysis revealed that expression of vasoactive intestinal peptide (VIP) was significantly suppressed in MMP14‐KO mesenchymal cells. VIP and VIP receptor 1 (VIPR1) were mainly expressed in periportal mesenchymal cells and cholangiocytic progenitors during IHBD development, respectively, in vivo. VIP/VIPR1 signaling significantly encouraged cholangiocytic cyst formation and up‐regulated tight junction protein 1, cystic fibrosis transmembrane conductance regulator, and aquaporin 1, in vitro. VIP antagonist significantly suppressed the tight junction assembly and the up‐regulation of ion/water transporters during IHBD development in vivo. In a cholestatic injury model of adult mice, exogenous VIP administration promoted the restoration of damaged tight junctions in bile ducts and improved hyperbilirubinemia. Conclusion: VIP is produced by periportal mesenchymal cells during the perinatal stage. It supports bile duct development by establishing tight junctions and up‐regulating ion/water transporters in cholangiocytes. VIP contributes to prompt recovery from cholestatic damage through the establishment of tight junctions in the bile ducts.

Cardiac power output accurately reflects external cardiac work over a wide range of inotropic states in pigs

BackgroundCardiac power output (CPO), derived from the product of cardiac output and mean aortic pressure, is an important yet underexploited parameter for hemodynamic monitoring of critically ill patients in the intensive-care unit (ICU). The conductance catheter-derived pressure-volume loop area reflects left ventricular stroke work (LV SW). Dividing LV SW by time, a measure of LV SW min− 1 is obtained sharing the same unit as CPO (W). We aimed to validate CPO as a marker of LV SW min− 1 under various inotropic states.MethodsWe retrospectively analysed data obtained from experimental studies of the hemodynamic impact of mild hypothermia and hyperthermia on acute heart failure. Fifty-nine anaesthetized and mechanically ventilated closed-chest Landrace pigs (68 ± 1 kg) were instrumented with Swan-Ganz and LV pressure-volume catheters. Data were obtained at body temperatures of 33.0 °C, 38.0 °C and 40.5 °C; before and after: resuscitation, myocardial infarction, endotoxemia, sevoflurane-induced myocardial depression and beta-adrenergic stimulation. We plotted LVSW min− 1 against CPO by linear regression analysis, as well as against the following classical indices of LV function and work: LV ejection fraction (LV EF), rate-pressure product (RPP), triple product (TP), LV maximum pressure (LVPmax) and maximal rate of rise of LVP (LV dP/dtmax).ResultsCPO showed the best correlation with LV SW min− 1 (r2 = 0.89; p < 0.05) while LV EF did not correlate at all (r2 = 0.01; p = 0.259). Further parameters correlated moderately with LV SW min− 1 (LVPmaxr2 = 0.47, RPP r2 = 0.67; and TP r2 = 0.54). LV dP/dtmax correlated worst with LV SW min− 1 (r2 = 0.28).ConclusionCPO reflects external cardiac work over a wide range of inotropic states. These data further support the use of CPO to monitor inotropic interventions in the ICU.

P4687Relevance of TAPSE and FAC, and their relationship to PASP as echo-derived measures for RV-PA coupling in heart failure: a comparative analysis with invasive RV-pressure volume loop data

Abstract Background Right ventricular (RV) to pulmonary artery (PA) coupling (C), quantified by pressure volume (PV) loop analysis, predicts RV function, and is independently associated with long term survival in systolic heart failure (HFrEF). However, the PV loop technique is invasive and complex to carry out, especially when used to do RV functional analyses. Different echo-surrogate parameters are proposed to measure RV-PA-C, such as the tricuspid annular plane systolic excursion, TAPSE/PAsystolic pressure (SP) and FAC (fractional area change)/PASP as the most promising parameters. However, up to now, no validation of these non-invasive coupling indices with the invasive gold standard method of RV-PV-loops has been done. Methods In 111 patients with advanced HFrEF (Post-hoc analysis of Magdeburger CRT Responder Trial, DRKS00011133), echo-derived TAPSE and FAC, and their relationship to PASP were related to the RV PV-loop-derived parameters of intrinsic RV contractility (Ees), pulmonary load (Ea), and the RV-PA-C efficiency (Ees/Ea) by linear regression analysis. Within a MRI substudy (n=49 patients) we examined the relationship of pure longitudinal contraction (MRI-TAPSE) and radial free wall to septum contraction (area change of 5 RV segments from tricuspid valve to apex in the short axis view) to the invasive RV-PA-C. Results The MRI analysis demonstrated that radial RV contraction (R2=0.77, p&lt;0.001) correlated better to invasive RV-PA-C than pure longitudinal shortening (R2=0.37, p&lt;0.001) (radial vs. longitudinal: p&lt;0.00). Echo data for the entire patient cohort confirmed the MRI data. The FAC (R2=0.8, p&lt;0.001) was significantly better associated with RV-PA-C than TAPSE (R2=0.57, p&lt;0.001) (TAPSE vs FAC, p&lt;0.001). Placing TAPSE or FAC into a quotient with PASP did not at all (TAPSE vs. TAPSE/PASP, p=0.1) or significantly attenuated (FAC vs. FAC/PASP R2=0.8 vs 0.58, p&lt;0.001) their association to RV-PA-C. However, FAC/PASP and TAPSE/PASP correlated significantly better with global afterload (Eea), PA compliance, and pressure volume area (PVA), (p&lt;0.001). In ROC analysis for all-cause mortality, all 4 tested parameters were prognostic relevant, however, with higher AUC values for FAC/PASP (AUC=0.74, p&lt;0.001) and TAPSE/PASP (AUC=0.74, p&lt;0.001) than for single TAPSE (AUC= 0.71, p=0.001) or FAC (AUC=0.7, p=0.001). Within a multivariate Cox regression analysis, only the FAC/PASP remained an independent predictor for long term survival. Conclusion FAC, an echo parameter that includes a predominant radial with a smaller part of longitudinal contraction, correlated significantly better to the invasively derived RV-PA-C-ratio than pure longitudinal RV shortening (TAPSE). Combining FAC or TAPSE with PASP did not improve the non-invasive RV-PA coupling information. However, it provided more comprehensive information on pulmonary vascular load and RV oxygen consumption, which seems to be translated into a higher prognostic power. Acknowledgement/Funding scientific grant from Boston Scientific

P5749Haemodynamical effects o fleft ventricular assistance during high-risk percutaneous coronary interventions with a pneumatic left ventricular assist device

Abstract Background Referral for high-risk percutaneous coronary intervention (PCI) is a progressively growing trend. Percutaneous Mechanical Circulatory Support (MCS), may protect the myocardium and reduce the risk of major adverse events. Clinical data on Left Ventricular (LV) unloading by pneumatically driven Percutaneous Left Ventricular Assist Devices (pVAD's) is currently scarce. Purpose Describe the unloading pattern produced by a pneumatically driven pulsatile pVAD on LV haemodynamics through real-time Pressure-volume (PV) analysis with a conductance catheter positioned in the left ventricle. Methods 19 patients undergoing high-risk PCI treated with MCS were monitored with PV loops and pulmonary artery catheterization throughout the intervention. Results When activated on 1:1 assist ratio, the mean output produced by the pVAD was 1.36±0.13L/min. Compared to pre-implantation, 1:1 support produced a significant reduction in End-systolic Wall Stress (ΔWSes: −11.95%, p&lt;0.01) and PV area (ΔPVA: −16.67%, p&lt;0.01). Contractility did not significantly change (ΔV100: +29.48%, p=0.073; End-systolic Elastance, ΔEes: 1.24%, p=0.86). Effective Arterial Elastance (Ea), representing afterload, decreased (ΔEa: −12.05%, p&lt;0.05). Total Arterial Compliance (ΔTAC: +31.59, p&lt;0.01) increased and Ventricular-arterial Coupling (ΔEa/Ees: −9.79%, p=0.06) non-significantly improved. Mean arterial pressure non-significantly decreased (ΔMAP: −6.66%, p=0.06) and global Cardiac Output remained stable (ΔCO: −0.06%, p=0.37). When the pVAD was removed after the PCI these changes were reversed (Figure 1). Image 1 Conclusion High-risk PCI with pneumatic MCS may result in LV unloading and reduced myocardial oxygen consumption. Further insights will be released in the PULSE trial (Clinicaltrials.gov NCT03200990).

P625Impact of hemodialysis on a novel and noninvasive index for quantification of stroke work obtained by left ventricular pressure-volume loop area using speckle tracking echocardiography

Abstract Background Left ventricular (LV) pressure-strain and pressure-volume (P-V) loop area reflect global myocardial work (MW) and stroke work (SW), but clinical use of these indexes is limited by the need of invasive pressure measurement. A noninvasive method to obtain LV pressure-strain loop area was recently introduced to examine MW by speckle tracking echocardiography (STE). Purpose We sought to evaluate the impact of preload change on MW and SW obtained using this novel method and to examine the utility to assess LV contractile performance by the SW and end-diastolic volume (EDV) relation (SW-VED) in patient with hemodialysis (HD). Methods LV pressure in a cardiac cycle was estimated using systolic blood pressure (SBP), LV minimum diastolic pressure (mDP) and end-diastolic pressure (EDP) in 20 HD patients (age 67±9)and 25 controls (age 67±9) by utilizing the profile of an empiric, normalized reference curve adjusted according to the duration of LV isovolumic and ejection phases as defined by timing of aortic and mitral valve events by echocardiography. Pulmonary capillary wedge pressure (ePCWP) is estimated as 10.8 – 12.4 × Log (left atrial active emptying function/minimum volume): KT index as previously reported. LVEDP were estimated as 12.3 – 10.1 × KT index. We examined the relation between LV pressure decline (Tau) and mDP by catheterization in 126 patients. Tau is estimated as isovolumic relaxation time/(ln 0.9 × systolic BP − ln ePCWP) as previously reported. SW was obtained by P-V loop area using the combination of pressure (SBP, mDP and EDP) and LV volume by 3D-STE. Echo parameters and BP were measured before and after HD and before and after leg up in controls. Results The mDP obtained by catheterization had a good correlation with Tau (Tau = 33.7 + 2.06 × mDP, r=0.70, p&lt;0.01). LVEF by 3D-STE was increased in controls after leg up (59±5 to 62±4%) associated with increased LVEDV (85±25 to 91±26ml), whereas there was no difference in LVEF before and after HD (61±9 vs 61±10%) instead of decreased EDV after HD (101±23 to 92±24ml). SBP and PCWP in HD was decreased after HD (SBP: 149±25 to 140±15, PCWP: 9.8±4.3 to 8.5±3.6mmHg). MW and SW were increased after leg up in controls (1706±443 to 1972±461mmHg% and 4072±1938 to 5044±1958mmHgml) and those were decreased after HD (1964±441 to 1794±756mmHg% and 5475±1335 to 4722±1949mmHgml). LV SW-VEDin HD without LV dilation (EDVI&lt;70ml/m2, n=12) was decreased compared to controls (143±115 vs 241±152) and that in HD with LV dilation was further decreased compared to HD without dilation. Conclusion LVSW noninvasively obtained by P-V loop area was increased in controls associated with increased preload and decreased in HD with decreased preload and SW-VED was deceased in HD. This novel and noninvasive method may be of potential utility to assess LV contractility and have a clinical interest and value to assess LV function.

P4384Noninvasive and novel method to evaluate left ventricular contractility using pressure-volume loop area obtained by 3-dimensional speckle tracking echocardiography

Abstract Introduction Left ventricular (LV) pressure-volume (P-V) loop area reflects stroke work (SW), but clinical use of this index is limited by the need of invasive pressure measurement. A noninvasive method to obtain LV pressure-strain loop was recently introduced to assess myocardial work (MW). The minimum LV diastolic pressure (mLVP) was reported to have a strong correlation with Tau and we reported that Tau was noninvasively evaluated by speckle tracking echocardiography (STE). Purpose We sought to evaluate the impact of preload change by leg lifts on LV SW noninvasively obtained by the novel method and to examine the utility to assess LV contractility by SW and end-diastolic (ED) volume relation (SW-VED). Methods Thirty six controls (age 71±10) and 30 patients with heart failure with reduced ejection fraction (EF) &lt;50% (HF) (age 73±6) were enrolled. LV pressure in a cardiac cycle was estimated using systolic blood pressure (SBP), minimum diastolic pressure (mDP) and ED pressure (EDP) by utilizing the profile of an empiric, normalized reference curve. The mDP and EDP were estimated as (Tau − 33.7)/2.06 and as 12.3 − 10.1 x Log (left atrial active emptying function/minimum volume) as we reported. LVSW was obtained by P-V loop by the combination of these pressures and LV volume using 3-D STE. Results LVEF and longitudinal strain in HF before leg up by 3D-STE were lower compared to normal (LVEF; normal: 58±5 vs HF: 39±10*% and strain; −12±3 vs −8±3%*, *p&lt;0.05 vs normal). LVEF was increased after leg up by 7±6% in normal and by 8±8% in HF associated with increased LVED volume (normal: 84±24 to 90±24 and HF: 124±36* to 136±42*ml). LV MW and SW in HF before leg up were lower compared to normal (MW: 1790±412 vs 1002±432*mmHg% and SW: 3946±1682 vs 3352±1026mmHgml). LV SW increased after leg up by 26±19% in normal and by 25±20% in HF. LV SW-VED in normal was greater than HF (241±151 vs 90±54*). Conclusion LV SW noninvasively obtained by P-V loop area was increased after leg up in both normal and HF but SW-VED in HF was smaller than normal, indicating reduced contractility in HF. This noninvasive method may be a new echocardiographic approach for quantification of LV SW and contractility.

Energy Storage Design Using Physics-Based Battery Models in Hybrid Power Systems with Uncertainties

Renewable energy resources (RERs) have the potential to satisfy the continuously growing energy demand and provide power to un-electrified remote locations. The power generated by RERs is not always reliable due to its dependence on atmospheric conditions like solar radiation, wind speed, and temperature. To provide uninterrupted power throughout day and night, and to ensure the power stability in the system, a battery energy storage (BES) system may be coupled with a standalone RER system [1]. Proper sizing of the BES system is crucial to make such hybrid power systems technically and economically feasible. Generally, empirical or equivalent circuit models (ECM) are used to calculate different battery parameters which are easy to solve, but not accurate enough to accommodate rapid changes in operating conditions and their effects on the battery’s transport and kinetic parameters which might lead to under-utilization and over-stacking of batteries, increasing the cost of the BES systems. Physics-based battery models can offer better prediction of battery parameters like the state of charge, cell degradation, and amount of energy remaining in the battery thereby enabling us to get the best energy storage design results. This presentation will illustrate the use of physics-based battery models to design the BES system for a standalone PV-BES hybrid power system. The graphical and numerical Pinch Analysis techniques help in finding the minimum resource targets and the detailed design of the standalone RER system. A Power Pinch Analysis (PoPA) framework [2] is used for determining the minimum PV area, and the battery capacity is calculated using physics-based battery models. A single particle model (SPM) [3] and a pseudo-two-dimensional (P2D) model [4] are used for simulating the dynamic behavior of the lithium-ion battery. A framework is developed to evaluate the performance of a PV-BES hybrid power system using SPM [5], and LIONSIMBA [6] is used for the simulation of a P2D model. The chance constrained programming [7] is incorporated to consider renewable resource uncertainty. The minimum PV area and its extreme limits are calculated with a specified system reliability level using the concept of PoPA. An illustrative example of PV-BES hybrid power system is provided to demonstrate the effectiveness of the proposed strategy using real-world data. The results of the proposed approach are compared with the literature [2], and improvements in predicting battery storage capacity are shown in Figure 1. Also, load demand uncertainty is an essential issue in the design of RER based hybrid power system to satisfy the specified reliability [8]. One of the objectives is to incorporate uncertainty associated with the load demand to estimate BES system capacity. Available PoPA tools in the literature have been mainly focused on calculating minimum RER area, however incorporating changes in battery chemistry is also equally crucial to predict battery life. The developed PoPA framework would be extended further by considering the capacity fade that occurs during battery operation under varying climatic conditions and ambient temperature to accurately design the BES system. The number of battery modules and their performance can also be optimized using these models. This work combines the simplicity of PoPA to calculate the RER area and physics-based battery models to represent complex battery chemistry. However, this framework is generic in nature and can be easily extended further to include a combination of several RERs and different storage technologies for hybrid power systems.

Energetic and economic evaluation of hybrid solar energy systems in a residential net-zero energy building

Net-zero energy buildings are playing a critical role in the decarbonization of future cities since the buildings are responsible for 30–40% of total energy consumption. A residential net-zero energy building with a prospect of commercialization was introduced, which adopts solar energy systems and heat insulation solar glass that simultaneously generates electric power and minimizes heat loss. Dynamic and parametric simulation models were developed based on the TRNSYS platform and were validated by experimental data or standard test reports. A multi-criteria decision-making framework based on the energetic and economic criteria was developed to evaluate system performance and to find the favorable layout of the energy system in the residential net-zero energy building. Twelve system scenarios, covering the individual heat insulation solar glass system, the hybrid systems integrated with solar PV, solar thermal and heat insulation solar glass, and the hybrid systems combined solar thermal and heat insulation solar glass, were comparatively assessed. Among the system scenarios inclusive of solar thermal technology, a combination of the compound parabolic concentrated solar collector and variable-effect absorption chiller is highly recommended. However, the system scenario, which consists of a specific PV area of 8.4 m2/kW and employs heat insulation solar glass, is most favorable due to a highest primary energy saving ratio of 1.05 and a lowest levelized total cost of 5920 US$/year. All system scenarios proposed herein are not economically feasible at the current economic parameters in Singapore’s climate. However, the optimized hybrid system (integrated with solar PV, solar thermal and heat insulation solar glass) is sufficient to reach the net-zero energy target while the optimized solar PV system combined heat insulation solar glass is a solution of the positive energy building.

Salutary Effects of the PULVAD, a Novel Implantable Counterpulsation Assist Device, on Cardiac Mechanoenergetics.

The Pressure Unloading Left Ventricular Assist Vevice (PULVAD) is a novel implantable counterpulsation LVAD, designed to provide ventricular unloading with augmentation of LV performance and retention of pulsatility. We assessed the effects of the PULVAD on hemodynamics and LV mechanoenergetics in seven farm pigs with acute ischemic heart failure. The PULVAD was implanted in the thorax and was connected to the ascending aorta. The PULVAD was pneumatically driven by a standard intra-aortic balloon pump console and was electrocardiogram-synchronized to provide LV pressure unloading along with diastolic aortic pressure augmentation. Hemodynamics, indices of LV mechanoenergetics, and coronary blood flow were measured without and after brief PULVAD support. PULVAD support decreased LV afterload and improved LV mechanical performance (increased ejection fraction, stroke volume, cardiac output and maximum elastance). The PULVAD concurrently reduced LV energy consumption (decreased stroke work and pressure-volume area) and optimized LV energetic performance (improved the ratio of stroke work to pressure-volume area). PULVAD support increased mean coronary blood flow, through dramatic augmentation of diastolic blood flow. In conclusion, the PULVAD unloads the failing LV, optimizes LV mechanoenergetics, and augments coronary blood flow. These salutary effects of short-term PULVAD support provide the foundation for long-term testing.