Flow Left Ventricular Assist Device Research Articles

Enhancing the implantation of mechanical circulatory support devices using computational simulations.

Introduction: Patients with end-stage heart failure (HF) may need mechanical circulatory support such as a left ventricular assist device (LVAD). However, there are a range of complications associated with LVAD including aortic regurgitation (AR) and thrombus formation. This study assesses whether the risk of developing aortic conditions can be minimised by optimising LVAD implantation technique. Methods: In this work, we evaluate the aortic flow patterns produced under different geometrical parameters for the anastomosis of the outflow graft (OG) to the aorta using computational fluid dynamics (CFD). A three-dimensional aortic model is created and the HeartMate III OG positioning is simulated by modifying (i) the distance from the anatomic ventriculo-arterial junction (AVJ) to the OG, (ii) the cardinal position around the aorta, and (iii) the angle between the aorta and the OG. The continuous LVAD flow and the remnant native cardiac cycle are used as inlet boundaries and the three-element Windkessel model is applied at the pressure outlets. Results: The analysis quantifies the impact of OG positioning on different haemodynamic parameters, including velocity, wall shear stress (WSS), pressure, vorticity and turbulent kinetic energy (TKE). We find that WSS on the aortic root (AoR) is around two times lower when the OG is attached to the coronal side of the aorta using an angle of 45° ± 10° at a distance of 55mm. Discussion: The results show that the OG placement may significantly influence the haemodynamic patterns, demonstrating the potential application of CFD for optimising OG positioning to minimise the risk of cardiovascular complications after LVAD implantation.

(819) - Evaluation of Platelet Activation by Flow Cytometry in Contemporary Continuous Flow Left Ventricular Assist Device Support

(819) - Evaluation of Platelet Activation by Flow Cytometry in Contemporary Continuous Flow Left Ventricular Assist Device Support

Abstract 18880: Ventricular Arrhythmia Prevalence and Burden in Patients With Third Generation Continuous Flow Left Ventricular Assist Devices

Background: Ventricular arrhythmias (VAs) are common in patients with left ventricular assist devices (LVADs). Little is known about the impact of third-generation LVADs (Heartmate 3, HM3) on VAs prevalence and burden. Aims : To characterize the impact of HM3 LVAD implantation on VAs prevalence and burden in patients with advanced heart failure (HF) and implantable cardioverter-defibrillators (ICDs). Methods: We included consecutive patients with advanced HF and ICDs who received HM3 devices at our center between 2016 and 2022. The study outcomes were the prevalence of sustained VAs, defined as >30s VA episode detected by the ICD monitor zone or appropriately treated (ATP or shock), sustained VA burden (total number of episodes), and VA storm (≥3 appropriate ICD interventions in 24/h period). Data was collected over the 1 year before and after HM3 implantation. Results: A total of 321 patients were included (28% female, mean age 60±12 years, mean INTERMACS score 3±0.95). At 1 year follow-up after HM3 implantation, 27 patients died. A total of 128 patients (43%) had at least one sustained VA episode in the year before the HM3 implantation compared to 51 patients (17%) in the year following the HM3 (p<0.001 for comparison). The sustained VA burden decreased from a mean of 3.8 events per person-year (PPY) to a mean of 0.8 events PPY (p=0.005). Similarly, appropriate ICD therapy occurred in 123 patients (38%) before implantation and 46 patients (14%) after implantation (p<0.001). The burden of appropriate therapy was also reduced (from a mean of 2.57 events PPY to a mean 1.32 events PPY; p=0.03). The prevalence of VA storm was reduced from 19% to 8% (p<0.001). Conclusions: In patients with advanced HF and ICDs undergoing HM3 implantation, the prevalence of sustained VAs, VAs burden, appropriate ICD interventions, and VA storm were all significantly reduced in the year following HM3 implantation.

Abstract 13623: In Silico Comparison of Pressure Head Loss for Outflow Variations of a Novel LVAD Accessory Compared to Generic LVAD Pump Outflow

Introduction: Left ventricular assist device (LVAD) implantation is a treatment option for end-stage heart failure, requiring a sternotomy. A novel accessory, redirecting the outflow via the left ventricular apex into the ascending aorta, allows for LVAD implantation via left thoracotomy. Pressure distribution within accessory designs is unknown. Our goal was to compare three different outflow designs with a generic LVAD outflow (Control) to optimize the accessory’s outflow design. Hypothesis: We hypothesize that the LVAD accessory leads to higher pressure head loss than Control and that there are relevant differences among varied designs. Methods: Volume models of the LVAD accessory variations (A–C) and Control were created using computer aided design. Computational fluid dynamics (CFD) was used to simulate blood flow through the accessories and generic outflows. A verification study was performed to optimize numerical parameters. Pressure head loss (mmHg) was calculated for each outflow while changing the LVAD flow rate continuously (2–7 L/min). Pressure loss was compared by mean differences (MD). Results: Pressure head loss increased with higher LVAD flow rate among all groups. Addressing the accessories’ outflow designs, Design B revealed the lowest increase in pressure loss revealing a mean slope of 2.3 mmHg/L/min compared to 4.6 and 3.0 for Design A and C. Referring to a flow rate of 5.5 L/min, a common flow rate among clinical LVAD patients, and comparing pressure head loss with Control, we found an additional pressure loss of 15.5, 6.4 and 8.3 mmHg in Design A, B and C, respectively. Conclusion: There is a trade off between fitting the outflow design to the cardiac geometry and the pressure head loss. Continued optimization of the LVAD accessory could allow minimally invasive LVAD implantation with minimal changes in LVAD performance. Potential compromise between improved design and performance renders CFD an important tool for medical device development.

Percutaneous left ventricular assist devices in refractory cardiac arrest: The role of chest compressions

Recent studies describe an emerging role for percutaneous left ventricular assist devices such as Impella CP® as rescue therapy for refractory cardiac arrest. We hypothesized that the addition of mechanical chest compressions to percutaneous left ventricular assist device assisted CPR would improve hemodynamics by compressing the right ventricle and augmenting pulmonary blood flow and left ventricular filling. We performed a pilot study to test this hypothesis using a swine model of prolonged cardiac arrest. Eight Yorkshire swine were anesthetized, intubated, and instrumented for hemodynamic monitoring. They were subjected to untreated ventricular fibrillation for 5.75 (SD 2.90) minutes followed by mechanical chest compressions for a mean of 20.0 (SD 5.0) minutes before initiation of percutaneous left ventricular assist device. After percutaneous left ventricular assist device initiation, mechanical chest compressions was stopped (n=4) or continued (n=4). Defibrillation was attempted 4, 8 and 12 minutes after initiating percutaneous left ventricular assist device circulatory support. The percutaneous left ventricular assist device+mechanical chest compressions group had significantly higher percutaneous left ventricular assist device flow prior to return of spontaneous heartbeat at four- and twelve-minutes after percutaneous left ventricular assist device initiation, and significantly higher end tidal CO2 at 4-minutes after percutaneous left ventricular assist device initiation, when compared with the percutaneous left ventricular assist device alone group. Carotid artery flow was not significantly different between the two groups. The addition of mechanical chest compressions to percutaneous left ventricular assist device support during cardiac arrest may generate higher percutaneous left ventricular assist device and carotid artery flow prior to return of spontaneous heartbeat compared to percutaneous left ventricular assist device alone. Further studies are needed to determine if this approach improves other hemodynamic parameters or outcomes after prolonged cardiac arrest.

Personalized Numerical Cardiovascular Model with Weight Growth for Evaluating Pediatric Left Ventricular Assist Devices: Derivation from an Experimental Mock Circulatory Loop.

Pediatric patients with heart failure have limited treatment options because of a shortage of donor hearts and compatible left ventricular assist devices (LVADs). To address this issue, our group is developing an implantable pediatric LVAD for patients weighing 5-20kg, capable of accommodating different physiological hemodynamic conditions as patients grow. To evaluate LVAD prototypes across a wide range of conditions, we developed a numerical cardiovascular model, using data from a mock circulatory loop (MCL) and patient-specific elastance functions. The numerical MCL was validated against experimental MCL results, showing good agreement, with differences ranging from 0 to 11%. The numerical model was also tested under left heart failure conditions and showed a worst-case difference of 16%. In an MCL study with a pediatric LVAD, a pediatric dataset was obtained from the experimental MCL and used to tune the numerical MCL. Then, the numerical model simulated LVAD flow by using an HQ curve obtained from the LVAD's impeller. When the numerical MCL was validated against the experimental MCL, hemodynamic differences ranged between 0 and 9%. These findings suggest that the numerical model can replicate various physiological conditions and impeller designs, indicating its potential as a tool for developing and optimizing pediatric LVADs.

Less Invasive Left Ventricular Assist Device Implantation Is Safe and Feasible in Patients With Smaller Body Surface Area.

Smaller body surface area (BSA) frequently precludes patients from left ventricular assist device (LVAD) therapy. We sought to investigate the clinical outcomes in patients with small BSA undergoing less invasive LVAD implantation. We conducted a retrospective review of 216 patients implanted with HeartMate 3 LVAD (Abbott, Chicago, IL) via less invasive surgery at our institution. Patients were dichotomized based on their preimplant BSA for comparison between small BSA (≤1.8 m2) and normal/large BSA (>1.8 m2). We analyzed patient perioperative characteristics and outcomes. In our study, small BSA was found in 32 patients (14.8%), while 184 patients (85.2%) had normal/large BSA. Women were more prevalent in the small BSA group (50.0% vs 13.0%, P < 0.001). Preoperative and intraoperative data showed comparable results. Major complications and hospital length of stay did not differ by BSA group. Patients with smaller BSA had significantly decreased pump parameters at discharge, including LVAD flow (4.11 ± 0.49 vs 4.60 ± 0.54 L/min, P < 0.001) and pump speed (5,200 vs 5,400 rpm, P < 0.001). Survival to discharge and within 6 months after implantation were similar between the groups. Our study results suggest that less invasive HeartMate 3 implantation can be safely performed and demonstrates equivalent outcomes in patients with smaller body habitus. Randomized trials are required to confirm our data.

Stable Ventricular Fibrillation: A Paradigm Rather Than Septal Shift?

Awake patients in ventricular fibrillation is a phenomenon limited to patients who are mechanically supported. We describe a cohort of patients supported by left ventricular assist devices (LVADs) presenting to the emergency department (ED) at a high-volume LVAD center while in awake ventricular fibrillation (VF)/ventricular tachycardia (VT). Among 175 patients reviewed, a total of 19 LVAD patients presented to the ED in awake VF/VT between December 2015 and July 2021. On ED presentation, patients maintained a median mean arterial blood pressure (MAP) of 70 mm Hg with a mean LVAD flow of 3.77 L/minute. ED management included cardioversion in the majority of cases: 58% were defibrillated once, 21% were defibrillated multiple times, 68% received amiodarone, and 21% received lidocaine. Inpatient management included defibrillation, ablation, and antiarrhythmic initiation in 37%, 11%, and 84% of cases, respectively. In total, five patients (26%) died with one death attributed to recurrent VT. Our findings support the short-term tolerability of sustained ventricular arrhythmias in LVAD patients, as evidenced by the maintained MAPs and mental status. Clinical teams, however, should be aware of the potential harbinger for in-hospital mortality heralded by an awake VF/VT presentation.

Sensor-Free Biosensing of Mitral and Aortic Valvular Function During Continuous Flow Left Ventricular Assist Device Support

Sensor-Free Biosensing of Mitral and Aortic Valvular Function During Continuous Flow Left Ventricular Assist Device Support

A Multi-objective Physiological Control for Continuous Flow Left Ventricular Assist Devices: Comparison of Estimator versus Sensor-based Feedback.

Left Ventricular Assist Devices have been successfully used for the treatment of Congestive Heart failure in patients who are not eligible for heart transplantation. This paper describes the implementation and comparison of the performance of a pressure sensor-based feedback controller. The strategies were tested on a mock loop of the systemic circulation. The results show that the use of pressure sensors generated a more accurate response of the controller compared to the use of estimators.Clinical Relevance- The study describes the integration of a LVAD physiological controller to a dynamic wireless monitoring system.

Association of Nutritional Risk Index With Continuous Flow Left Ventricular Assist Device Complications

Studies revealing the relationship between major surgery outcomes and nutritional parameters are increasing daily. Publications demonstrating the relationship between early postoperative success and surgical complications in patients with chronic heart failure and continuous flow left ventricular assist device (cf-LVAD) are limited. The vast majority of patients with advanced chronic heart failure are cachexic, and the reason for this is multifactorial. The aim of this study is to investigate the link between the modified nutritional risk index (NRI) and 6-month survival and complication rates in patients with a cf-LVAD. This study included statistical analysis of NRI and postoperative parameters of 456 patients with advanced heart failure who had cf-LVAD implantation between 2010 and 2020. The results of this study showed a statistically significant difference between mean NRI values and postoperative parameters such as 6-month survival (P=.001), right ventricular failure (P=.003), infection (P=.001), driveline infection (P=.000), and sepsis (P=.000). This study revealed that 6-month postoperative complications and mortality rates of patients with advanced heart failure in patients with cf-LVAD are closely related to malnutrition status. In these patients, nutrition specialist use would be beneficial both preoperatively and postoperatively to increase surveillance and reduce postoperative complications.

P14: Degradation of High Molecular Weight Multimers of von Willebrand Factor under Whole Blood Conditions in High Turbulent Flow: Implications for Continuous Flow Left Ventricular Assist Devices

Background: High turbulent flow often found in continuous flow left ventricular assist devices (cf-LVADs) is believed to cause acquired von Willebrand Syndrome (AvWS). Our group recently published a study on the kinetic and dynamic effects of various flows on the loss of high molecular weight multimers (HMWMs) of von Willebrand factor (vWF). In the study, we applied high shear to citrated human platelet-poor plasma (PPP) and characterized the flow by Reynolds number (Re). The present study aims to extend upon our previous findings by investigating the degradation of HMWM under whole blood conditions at higher flow conditions to be characterized by energy dissipation rate and clinically relevant exposure times previously employed. Methods: Diluted ovine blood with a hematocrit of 25%, dynamic viscosity of 3.0 cP and density of 1030 kg/m3 was flowed through a custom high shear rotary device. The device is designed to provide a fully controlled exposure time, texp and flow regime. The flow rate was set at 1.75 ml/sec, 0.76 ml/sec, or 0.38 ml/sec, resulting in an exposure time of 22 ms, 50 ms, or 100 ms, respectively. The dynamic flow condition was controlled by the speed of the rotor, ω, and characterized by the energy dissipation rate per unit mass, ε. The ω of 10k, 12k, 15k, 18k, 20k, and 22k RPM were applied, and the corresponding ε were estimated by running a series of large eddy simulations (LES). After each run, a 0.5 ml sample solution was collected, frozen in dry ice immediately, and shipped to the Blood Center of Wisconsin for multimer analysis. The amount of multimer degradation at each testing condition was assessed with respect to the mean of the initial concentration of HMWM of vWF in the controls. Results: The results show that the loss of HMWM at all given exposure times increases in a logarithmic manner within the extended flow conditions (Fig. 1A). The loss of HMWM versus energy dissipation rate at given texp is shown in Fig. 1B. It is noted that as the flow becomes more chaotic, the loss of HMWM appears to be primarily dominated by the energy dissipation rate while the exposure time to chaotic flow becomes less significant. It is not clear if the less significant effect of kinetics at relatively high flow conditions (>18k RPM) is because there are no more HMWM left to be cleaved by ADAMTS13, an enzyme that cleaves vWF. The results are consistent with our previous observations using human PPP, in that both flow conditions and exposure time play crucial roles in the destruction of HMWM. Conclusion: This study demonstrated the relative roles of flow and exposure time using whole blood to characterize the loss of HMWM in terms of energy dissipation rate and exposure time. The findings have the potential to assist in the design and optimization of blood pumps, ultimately leading to improved clinical outcomes for patients with AvWS.

P23: Preservation of Pulsatility with Universal Ventricular Assist Device: An In Vitro Assessment of Biventricular Support

Objective: The objective of this study was to assess the ability and performance of the Universal Ventricular Assist Device (UVAD) to maintain pulsatility when used as a biventricular assist device (BVAD) through an in vitro experiment utilizing a pulsatile biventricular mock circulatory loop. Methods: The UVAD pumps were evaluated in a dual configuration (BVAD) in the simulated circulatory model under conditions of left heart failure (HF), right HF, and moderate/severe biventricular HF. Measurements of total flow, pulse pressure in the aorta, pulse augmentation factor (PAF), energy-equivalent pressure (EEP), and surplus hemodynamic energy (SHE) were taken at various pump speeds to assess pulsatility. Results: The association between the maximum and minimum pressures and various parameters of the pump was determined during the cardiac cycle. It was observed that the pulse pressure increased across all heart conditions (Figure 1). The PAF ranged from 17-35% in healthy, LHF, RHF, and mild BHF conditions, with the highest PAF, 90%, being observed in the severe BHF condition. EEP correlated with LVAD flow in all groups (R2 = 0.87-0.97) and increased from baseline in all cases. SHE peaked at approximately 5-6 L/min of LVAD support and tended to dissipate surplus energy at higher LVAD pump flow. The greatest decrease in SHE from baseline, 53%, was observed in the mild BHF condition with the highest levels of left ventricular assist device (LVAD) and right ventricular assist device (RVAD) support. Conclusion: The UVAD successfully demonstrated the ability to preserve pulsatility in vitro, and to optimize cardiac output, as an isolated circulatory support device option (RVAD or LVAD), and when used for BVAD support.Figure 1. The relationships between LVAD/RVAD pump flow and aortic pulse pressure/PAF/EEP/SHE in each heart condition. LVAD, left ventricular assist device; RVAD, right ventricular assist device; AoP, aortic pressure; EEP, energy-equivalent pressure; SHE, surplus hemodynamic energy.

Testing radiofrequency energy delivery and catheter entrapment in three left ventricular assist device models in mock circulation

Abstract Funding Acknowledgements Type of funding sources: None. Background The use of Left Ventricular Assist Devices (LVAD) as a bridge to heart transplantation (HTx) or as a destination therapy is increasing. Near half of the patients had ventricular arrhythmias (VA) in the first year of LVAD support. Ablation is common method for recurrent ventricular tachycardias in LVAD patients. Even there are many case reports about successful VT ablations in LVAD patients there is no report about consequences of RF energy delivery inside LVAD or ablation catheter contact – entrapment to the rotor of the LVAD. Method Mock circulation models were created for three mostly used LVAD models ( Figure 1) (HeartMate3, HeartMate2, HVAD) Sheep heart was located inside the mock circulation model and 4mm non-irrigated RF ablation catheter and RF generator used for RF energy delivery tissue ( sheep heart) , ostium, mid and rotor of the LVAD)(Figure 1). During RF delivery flow parameters of the LVAD systems were noted also external noncontact flow monitor located out flow canula of the LVAD. All LVADs out flows were tested for 24 hours after RF energy delivery for long term malfunction. Also RF ablation catheters were tested for mechanical and functional disfunctions after contact of the LVAD rotors. Results No malfunctions were observed during and after RF energy delivery inside the LVADs. Only LVAD flow parameters temporary decreased in HeartMate 3 when the catheters had a contact to the rotor of the LVAD. This phenomenon occurred irrespective of RF energy delivery status. There were no changes in HVAD and Heartmate 2. After 24 hours continuous testing of the flow of the LVADs any changes were not observed . Impedance changes were noticed during RF energy delivery. Impedance values were dropped when RF catheter moved from tissue to the ostium of the LVAD in all models. Small increases observed during contact to the rotor of the LVAD in HeartMate 3 ( Figure 2). No mechanical damage were observed on the tip of the catheters after contact to the rotors also RF lesion dimensions were compared before and after the contact and there were no differences. Conclusion RF energy delivery and catheter entrapment of the RF catheters to the rotors of the LVADs caused no changes in LVAD functioning in ex-vivo conditions in a mock circulation.

Estimation of Left Ventricular Stroke Work for Rotary Left Ventricular Assist Devices.

Continuous monitoring of left ventricular stroke work (LVSW) may improve the medical management of patients with rotary left ventricular assist devices (LVAD). However, implantable pressure-volume sensors are limited by measurement drift and hemocompatibility. Instead, estimator algorithms derived from rotary LVAD signals may be a suitable alternative. An LVSW estimator algorithm was developed and evaluated in a range of in vitro and ex vivo cardiovascular conditions during full assist (closed aortic valve [AoV]) and partial assist (opening AoV) mode. For full assist, the LVSW estimator algorithm was based on LVAD flow, speed, and pump pressure head, whereas for partial assist, the LVSW estimator combined the full assist algorithm with an estimate of AoV flow. During full assist, the LVSW estimator demonstrated a good fit in vitro and ex vivo (R 2 : 0.97 and 0.86, respectively) with errors of ± 0.07 J. However, LVSW estimator performance was reduced during partial assist, with in vitro : R 2 : 0.88 and an error of ± 0.16 J and ex vivo : R 2 : 0.48 with errors of ± 0.11 J. Further investigations are required to improve the LVSW estimate with partial assist; however, this study demonstrated promising results for a continuous estimate of LVSW for rotary LVADs.

Late outflow graft stenosis of left ventricular assist device and endovascular treatment.

Left ventricular assist device (LVAD) systems are preferred as a bridging to transplantation or as a destination therapy in the treatment of end-stage heart failure. LVAD-related complications are seen in different clinical variations with the widespread use of LVADs. Some of these complications are seen as related to outflow graft, such as graft stenosis, graft kinking and graft thrombosis. Outflow graft complications have a direct impact on LVAD flow rate and acutely impair the clinical condition of patients. Treatment modalities include surgical approach, endovascular approach, and medical approach. In this case report, we aim to share a 57-year-old male patient, who had outflow graft stenosis near the anastomosis line between ascending aorta and the left ventricular assist device outflow graft, and the endovascular treatment.

Association of Age, Sex, and Heart Failure Etiology in Continuous Flow Left Ventricular Assist Device Patients

Advanced heart failure studies demonstrate that ischemic factors increase in prevalence with age and are more prominent in men. Ejection fraction (EF) cannot be preserved in these patients, and ischemic cardiomyopathy develops. Non-ischemic factors are more prominent in female heart failure patients, where the EF is preserved. Although an age-associated increase in the rate of heart failure is acknowledged in both sexes, etiologic classifications by sex-based age groups are still lacking. This study examined the etiology of heart failure according to age and sex in ventricular assist device patients. The patient population included 457 end-stage heart failure patients who received a continuous flow-left ventricular assist device at Ege University Hospital between 2010 and 2017. Age, sex, and cardiomyopathy etiology data were obtained from the hospital database. The Mann-Whitney U test was applied to test the statistical significance among subgroups (95% CI, P < .05 for statistical significance). The prevalence of ischemic cardiomyopathy was significantly lower in male patients aged 18 to 39 years compared to older patients. Conversely, no difference was seen among female patients. The prevalence of dilated cardiomyopathy was higher in male patients who were 18 to 39 years of age compared to older patients, but no difference was present among the female patients. Age and heart failure etiology were demonstrated to be interrelated in men but not in women. The fact that etiologic factors of advanced heart failure in women have a wider range than in men makes the current classification systems insufficient for use in female populations.

Impact of an Accessory for Left Ventricular Assist Devices on Device Flow and Pressure Head In Vitro.

A novel accessory directing the blood from the outflow of a left ventricular assist device (LVAD) back through the left ventricular apex and across the aortic valve allows LVAD implantation via the left ventricular apex solely but may affect the LVAD performance. We quantified the effect of the accessory on LVAD flow and pressure head in vitro. In a mock circulatory loop, a centrifugal-flow LVAD (HeartMate 3, Abbott, Abbott Park, IL, USA) with (Accessory) and without the accessory (Control) was compared under physiological conditions using a water/glycerol solution as a blood substitute. The pump was operated at 4000, 5200, and 6400 rpm and 5 different resistance levels. Flow, inlet, and outlet pressure were measured, and pressure head was calculated. Compared to the Control, flow and pressure head in the Accessory group were reduced by an overall average of 0.26 L/min and 9.9 mmHg (all speeds and resistance levels). The highest decline in flow and pressure head occurred at the lowest resistance levels. In conclusion, the accessory leads to a reduction of LVAD flow and pressure head that is enhanced by decreases in resistance. Future developments in the LVAD accessory's design may reduce these effects and allow unimpaired LVAD performance and minimally invasive device implantation.

Self-care behaviours of patients with left ventricular assist devices in Israel: changes during the COVID-19 pandemic.

Left ventricular assist devices (LVADs) support the hearts of patients with advanced heart failure. Following LVAD implantation, patients face a complex regimen of self-care behaviours including self-care maintenance, self-care monitoring and self-care management. However, during the COVID-19 pandemic, symptoms of anxiety and depression may have interfered with their self-care. Currently, little is known on how specific self-care behaviours of LVAD-implanted patients changed during the COVID-19 pandemic. We aim to describe the changes in self-care behaviours among patients with an implanted LVAD in Israel during the COVID-19 pandemic and explore the factors related to self-care behaviour change. A prospective observational cross-sectional study design. A convenience sample of 27 Israeli LVAD-implanted patients (mean age 62.4±9, 86% male, 78.6% living with a partner) completed the LVAD Self-Care Behaviour Scale (1=never to 5=always) and Hospital Anxiety and Depression Scale (0=not at all to 3=most of the time). Data were collected before and after the onset of the COVID-19 pandemic in Israel. Statistical analyses included paired t-tests, Pearson's correlations, and one-way repeated measures ANOVAs. During the COVID-19 pandemic, a significant decrease was found in patients' adherence to checking and recording their LVAD speed, flow, power and PI (Pulsatility Index) (P=0.05), checking their INR (P=0.01), and daily weighing (P<0.01). The prevalence of some behaviours (e.g. regularly exercising) increased in some patients and decreased in others. Patients living without a partner worsened their adherence to some of the self-care behaviours (e.g. taking medicines as prescribed), compared with those living with a partner (Mb =5.0±0 and Md =5.0±0, delta=0 vs. Mb =5.0±0 and Md =4.6±0.9, delta=-0.4, respectively; F=4.9, P=0.04). Women, and not men, tended to improve their adherence to the self-care behaviour such as avoiding kinking, pulling, or moving the LVAD driveline at the exit site (Mb =4.0±1.0 and Md =5.0±0, delta=1.0 vs. Mb =4.5±0.9 and Md =4.4±1.2, delta=-0.1, F=4.7, P=0.04, respectively). In total, 41% (11) patients reported neither anxiety nor depression, 11% (3) reported anxiety, 15% (4) reported depression, and 44% (12) reported both anxiety and depression. No associations between anxiety and/or depression and self-care behaviours were found. Priorities in self-care behaviours among patients with implanted LVAD changed after the onset of the COVID-19 pandemic. Factors that assisted with adherence to self-care behaviours included living with a partner and being female. The current results may guide further research on identifying behaviours that are at risk of not being maintained during a time of emergency.

(735) Impact of Asynchronous Rotational Speed Modulation of Continuous Flow Left Ventricular Assist Device on Cardiac Condition

(735) Impact of Asynchronous Rotational Speed Modulation of Continuous Flow Left Ventricular Assist Device on Cardiac Condition