Biventricular Assist Device Research Articles

Comparison of waitlist and post-transplant outcomes in patients supported with total artificial heart versus continuous biventricular assist devices.

Durable biventricular support may be necessary to bridge patients with end-stage biventricular failure to heart transplantation. This study compares waitlist and post-transplant outcomes between patients supported with continuous flow, durable biventricular assist devices (BiVAD), and total artificial heart (TAH). Using the UNOS registry, we analyzed adult (≥18 years old), first-time transplant candidates with TAH or BiVAD at the time of listing or transplantation from 10/1/2010-10/31/2020, with follow-up through 3/31/2022. Multivariable proportional subdistribution hazards models and cause-specific Cox proportional hazards models were used to compare death/deterioration or heart transplantation on the waitlist between cohorts. Kaplan-Meier and multivariable Cox proportional hazards model were used to evaluate one-year post-transplant survival and evaluate difference in outcomes based on annual transplant center volume. The waitlist cohort included a total of 228 patients (25% BiVAD). Waitlist outcomes between device types were similar. The transplanted cohort included a total of 352 patients (25% BiVAD). There was a trend towards worse one-year post-transplant survival in patients bridged with TAH versus BiVAD (log-rank p-value = 0.072) that persisted after adjusting for age, gender, policy, and removing dual-organ recipients (HR 1.94 (0.94, 3.98) p-value = 0.07). There was a difference in one-year post-transplant survival amongst TAH-bridged patients when stratified by annual transplant center volume (log-rank p-value = 0.013). One-year post-transplant survival between TAH-supported patients from high annual transplant volume centers and BiVAD-supported patients was similar (p-value = 0.815). BiVAD and TAH are reasonable support strategies with TAH implantation at high-volume transplant centers (51+ transplants/year) having similar 1-year post-transplant survival to BiVAD-supported patients.

Performance study of dual heart assisted control system based on SL-SMC physiological combination controller.

The main challenges of Biventricular Assist Devices (BiVAD) as a treatment modality for patients with Bicardiac heart failure heart failure are the balance of systemic blood flow during changes in physiological activity and the prevention of ventricular suction. In this study, a model of the Biventricular Circulatory System (BCS) was constructed and a physiological combination controller based on Starling-Like controller and Sliding Mode Controller (SMC) was proposed. The effects of the physiological controller on the hemodynamics of the BCS were investigated by simulating two sets of physiological state change experiments: elevated pulmonary artery resistance and resting-exercise, with constant speed (CS) control and combined Starling-like and PI control (SL-PI) as controllers. Simulation and experimental results showed that the Starling-like and Sliding Mode Control (SL-SMC) physiological combination controller was effective in preventing the occurrence of ventricular suction, providing higher cardiac output, maintain balance of systemic blood flow, and have higher response speed and robustness in the face of physiological state changes.

The Perioperative Period of Heart Transplantation Is Affected by Thyroid Hormone Status.

Background: Orthotopic heart transplantation (HTx) is a long-term surgical therapeutic approach for patients with end-stage heart failure. The objective of the present study was to uncover associations between altered thyroid hormone (TH) status and adverse outcomes after HTx. Methods: In this prospective, single-center cohort study, 283 patients underwent HTx between 2013 and 2020 at the Heart and Vascular Center of Semmelweis University in Hungary. We measured serum free triiodothyronine (fT3), free thyroxine (fT4), and thyrotropin (TSH) pre- and postoperatively. TaqMan qPCR was used to measure type 2 deiodinase and type 3 deiodinase mRNA (Dio2 and Dio3, respectively) levels from the diseased heart bioptates. To assess the local TH action of the heart, mRNA levels of Hcn2 and Myh7 were measured in a subgroup of patients receiving extracorporeal membrane oxygenation (ECMO) postoperatively. Groups were compared using nonparametric tests. Cox regression analysis and logistic regression test were used to investigate the outcomes. The connection between serum TH parameters and cardiac gene expressions was assessed using linear regression. Results: Serum TSH (p = 0.009), fT3 (p < 0.001), and fT4 (p < 0.001) levels were lower after HTx than preoperatively. Levothyroxine (LT4) administered to donors was associated with better survival after 30 days (p = 0.049). LT4 replacement given to recipients after HTx was associated with better survival after 30 days (p = 0.018), 1 year (p = 0.002), and 2 years (p = 0.001). Dio3 mRNA level was significantly increased in patients who were treated with ECMO (p = 0.026), left ventricular assist device (LVAD) (p = 0.008), and biventricular assist device (BiVAD) (p = 0.013) preoperatively, and ECMO (p = 0.042) postoperatively, compared with those who did not require any type of mechanical circulatory support (MCS). We found no significant difference in the expression of the Hcn2 and Myh7 marker genes between patients on postoperative ECMO and those without MCS, and neither did they correlate with serum hormone levels (p = 0.519 and p = 0.056, respectively). Conclusions: We conclude that TH status plays an important role in HTx patients, and monitoring of TH status in the perioperative period may contribute to improved treatment outcomes. Our findings require independent confirmation in a randomized controlled clinical trial.

Implantation of short-term biventricular assist device (BiVAD) using the CentriMag™ system: the Manchester technique.

Biventricular assist devices (BiVADs) using the CentriMag™ system are being used increasingly as a form of short-term mechanical circulatory support for the treatment of acute cardiogenic shock from any aetiology. They can be used as a bridge to decision, recovery or transplantation. BiVADs are associated with better clinical outcomes when compared to veno-arterial (VA) extracorporeal membrane oxygenator (ECMO) systems. In this paper, we describe a safe and reproducible method of BiVAD implantation using the CentriMag™ system at our institution.

(218) - The Effect of Rotational Speed Modulated Right Ventricular Assist Device on Hemodynamics in the Application of Continuous-Flow Biventricular Assist Device

(218) - The Effect of Rotational Speed Modulated Right Ventricular Assist Device on Hemodynamics in the Application of Continuous-Flow Biventricular Assist Device

(268) - Percutaneous Biventricular Assist Devices Require Fewer Transfusions and Returns to the Operating Room Compared to Classic Surgical Alternative

(268) - Percutaneous Biventricular Assist Devices Require Fewer Transfusions and Returns to the Operating Room Compared to Classic Surgical Alternative

Fully Magnetically Levitated Durable Biventricular Assist Device Insertion

Durable mechanical circulatory support options for patients with biventricular failure are limited. One emerging strategy is the use of two fully magnetically levitated durable ventricular assist devices (HeartMate 3s) in a biventricular configuration. The use of a HeartMate 3 as a right ventricular assist device (RVAD) requires several complex technical modifications. Here, we provide step-wise detailed figures and a comprehensive description of bilateral HeartMate 3 insertion, with a particular focus on right atrial inflow cannulation for the RVAD. Potential pitfalls and solutions are also described.

The outcomes of a standardized protocol for extracorporeal mechanical circulatory support selection-left ventricular challenge protocol.

There are no criteria for surgical mechanical circulatory system (MCS) selection for acute heart failure. Since 2021, we have utilized cardiopulmonary bypass system to assess patients' heart and lung condition to inform surgical MCS selection. we aimed to retrospectively analyze the outcomes of treatments administered using our protocol. We analyzed the data of 19 patients who underwent surgical MCS implantation. We compared patients' characteristics across the biventricular-assist device (BiVAD), central Y-Y extracorporeal membrane oxygenation (ECMO), central ECMO, and left VAD (LVAD) systems. Patients' diagnoses included fulminant myocarditis (47.4%), dilated cardiomyopathy (21.1%), acute myocardial infarction (15.8%), infarction from aortic dissection (5.3%), doxorubicin-related cardiomyopathy (5.3%), and tachycardia-induced myocarditis (5.3%). Eight patients (42.1%) underwent LVAD implantation, 1 (5.2%) underwent central ECMO, 4 (21.1%) underwent BiVAD implantation, and 6 (31.6%) underwent central Y-Y ECMO. 48h after surgery, both the pulmonary arterial and right atrial pressures were effectively controlled, with median values being 19.0mmHg and 9.0mmHg, respectively. No patients transitioned from LVAD to BiVAD in the delayed period. Cerebrovascular events occurred in 21.1%. Successful weaning was achieved in 11 patients (57.9%), and 5 patients (26.3%) were converted to durable LVAD. Two-year cumulative survival was 84.2%. Our protocol showed good results for device selection in patients with heart failure, and device selection according to this protocol enabled good control of the pulmonary and systemic circulations.

On the prediction of the effect of bi-ventricular assistance after cardiac explantation on the vascular flow physiology: A numerical study

Heart failure is a chronic and progressive condition characterized by the heart’s inability to pump sufficient blood to meet the body’s metabolic demands. It is a significant public health concern worldwide, associated with high morbidity, mortality, and healthcare costs. For advanced heart failure cases not responding to medical therapy, heart transplantation or mechanical circulatory support with ventricular assist devices (VADs) can be considered. In the specific case of bi-ventricular heart failure a replacement of both ventricles is required. In this context a Total Artificial Heart (TAH) may be proposed as a bridge to transplant solution. Additionally, bi-ventricular assist devices (BiVADs) are available to support both ventricles simultaneously. However Bi-ventricular heart failure management is difficult with poor outcomes. New surgical procedures appear to propose solutions after both ventricle failure. One of these intervention uses two continuous-flow VADs as a total artificial heart after cardiac explantation due to myocardial sarcoma. Unfortunately, this procedure makes patient management very difficult as pulmonary pressures and flow rate are no longer measurable after the surgical procedure. The setting of both pumps is hence a complex task for patient management. This article aims at helping clinicians on patient management undergoing double assistance after cardiac explantation by predicting the different outcomes on the vascular grid for all the possible rotational speed combination using a lumped model. Results provide a range of both pump operating conditions suitable for delivering a physiologically adapted flow to the vascular grid when combined with hypotensive treatments.

Clinical Outcomes of SARS-CoV-2 Infection in Pediatric Patients on Ventricular Assist Device Support: An ACTION Registry Analysis.

Adult patients on left ventricular assist device (LVAD) support have increased morbidity and mortality after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. There are no reported clinical data describing outcomes among pediatric patients on ventricular assist device (VAD) support infected with SARS-CoV-2. We conducted a retrospective study using the Advanced Cardiac Therapies Improving Outcomes Network (ACTION) registry to evaluate patient characteristics and clinical outcomes after SARS-CoV-2 infection. A total of 22 children on VAD support (median age at infection 10.6 years) from 16 centers tested positive for SARS-CoV-2. Cardiomyopathy (59.1%) and congenital heart disease (40.9%) were the most common primary diagnoses. The type of support included LVAD in 19 (86.4%), biventricular assist device (BIVAD) in one (4.5%), and single ventricle VAD in two (9%) patients. At the time of infection, 50% were outpatients, 23% were inpatients on a general cardiology floor, and 27% were in the cardiac intensive care unit (CICU). Most patients (82%) were symptomatic at time of diagnosis, but only 13% required escalation of respiratory support, and 31% received SARS-CoV-2 therapies. Notably, no mortality occurred, and significant morbidity was rare after SARS-CoV-2 infection in pediatric patients on VAD support.

Cardiological Challenges Related to Long-Term Mechanical Circulatory Support for Advanced Heart Failure in Patients with Chronic Non-Ischemic Cardiomyopathy.

Long-term mechanical circulatory support by a left ventricular assist device (LVAD), with or without an additional temporary or long-term right ventricular (RV) support, is a life-saving therapy for advanced heart failure (HF) refractory to pharmacological treatment, as well as for both device and surgical optimization therapies. In patients with chronic non-ischemic cardiomyopathy (NICM), timely prediction of HF's transition into its end stage, necessitating life-saving heart transplantation or long-term VAD support (as a bridge-to-transplantation or destination therapy), remains particularly challenging, given the wide range of possible etiologies, pathophysiological features, and clinical presentations of NICM. Decision-making between the necessity of an LVAD or a biventricular assist device (BVAD) is crucial because both unnecessary use of a BVAD and irreversible right ventricular (RV) failure after LVAD implantation can seriously impair patient outcomes. The pre-operative or, at the latest, intraoperative prediction of RV function after LVAD implantation is reliably possible, but necessitates integrative evaluations of many different echocardiographic, hemodynamic, clinical, and laboratory parameters. VADs create favorable conditions for the reversal of structural and functional cardiac alterations not only in acute forms of HF, but also in chronic HF. Although full cardiac recovery is rather unusual in VAD recipients with pre-implant chronic HF, the search for myocardial reverse remodelling and functional improvement is worthwhile because, for sufficiently recovered patients, weaning from VADs has proved to be feasible and capable of providing survival benefits and better quality of life even if recovery remains incomplete. This review article aimed to provide an updated theoretical and practical background for those engaged in this highly demanding and still current topic due to the continuous technical progress in the optimization of long-term VADs, as well as due to the new challenges which have emerged in conjunction with the proof of a possible myocardial recovery during long-term ventricular support up to levels which allow successful device explantation.

Preservation of pulsatility with universal ventricular assist device: In vitro assessment for biventricular support.

The objective of this study was to assess the pulsatility preservation capability of the universal ventricular assist device (UVAD) when used as a biventricular assist device (BVAD). This evaluation was conducted through an in vitro experiment, utilizing a pulsatile biventricular circulatory mock loop. Two UVAD pumps were tested in a dual setup (BVAD) in the circulatory model with the simulated conditions of left heart failure (HF), right HF, and moderate/severe biventricular HF (BHF). The total flow, aortic pulse pressure, the pulse augmentation factor (PAF), the energy-equivalent pressure (EEP), and the surplus hemodynamic energy (SHE) were observed at various pump speeds to evaluate the pulsatility. The aortic pulse pressure increased from the baseline (without pump) in all simulated hemodynamic conditions. The PAF ranged from 17%-35% in healthy, left HF, right HF, and mild BHF conditions, with the highest PAF of 90% being observed in the severe BHF condition. The EEP correlated with LVAD flow in all groups (R2 = 0.87-0.97) and increased from the baseline in all cases. The SHE peaked at approximately 5-6 L/min of LVAD support and was likely to decrease at higher LVAD pump flow. The largest decrease in SHE from the baseline, 53%, was observed in the mild BHF conditions with the highest LVAD and RVAD support. The UVAD successfully demonstrated the ability to preserve pulsatility in vitro, and to optimize the cardiac output, as an isolated circulatory support device option (RVAD or LVAD) and when used for BVAD support.

Interesting Image: Chest X-ray after Biventricular Assist Device (BiVAD) Implantation

Interesting Image: Chest X-ray after Biventricular Assist Device (BiVAD) Implantation

Heart Transplant Outcomes After Total Artificial Heart

We sought to compare heart transplant (HTX) outcomes from patients with a total artificial heart (TAH), biventricular assist device (BiVAD), or left ventricular assist device (LVAD) as a bridge to transplant (BTT). Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS)-Scientific Registry of Transplant Recipients (SRTR) created a dataset with TAH or durable mechanical circulatory support (MCS) who reached HTX between 2006 and 2015. The retrospective analysis compared TAH outcomes with those with a BiVAD or LVAD before HTX. The primary outcome was posttransplant survival at 1, 36, and 60 months. Secondary outcomes included simultaneous heart-kidney transplants, donor characteristics, and mortality risk factors. INTERMACS-SRTR cohort had, at the time of HTX, 2762 patients with LVAD; 205 BiVAD (139 durable and 66 temporary RVAD); 176 TAH (6 prior HeartMate II). Sixty months after HTX, mortality rates were 16.5% in the total group: LVAD 15.2%, BiVAD 22.4%, and TAH 29%. Survival differed between the LVAD, the TAH, and BiVAD but not between the BiVAD and TAH groups. One-year survival and complication rates were similar across groups-there was no difference in survival by donor age in the overall cohort. There was a difference in TTD based on recipient age in the LVAD group but not in BiVAD or TAH groups. Occurrence of HTX-kidney and post-transplant dialysis were higher in the TAH versus LVAD and BiVAD groups. The TAH is an efficacious BTT. Refinements in technology and patient selection may improve outcomes.

Biventricular Assist Devices as a Bridge to Heart Transplantation Under the New Donor Heart Allocation System in the United States.

Biventricular assist devices (BiVADs) for pre-heart transplant care is rare. The outcomes of pretransplant BiVAD support after the 2018 heart transplant allocation policy change are entirely unknown at this time. The United Network of Organ Sharing database was retrospectively queried from October 2018 to June 2022 to identify patients supported to transplant with BiVADs. They were compared to patients listed as Status 2 for heart transplantation with an isolated VAD (uni-VAD). The primary outcome of interest was 1 year survival. Secondary outcomes included length of stay, posttransplant stroke, dialysis, and pacemaker implantation. The frequency of BiVAD use for heart transplantation has remained unchanged after the 2018 allocation policy change, making up approximately 2% of transplant recipients annually. Patients supported with BiVADs appeared to be similar to patients supported with uni-VADs. One year survival was similar between the groups (88.57% vs. 87.90%). Length of stay was longer and there was a trend toward higher frequencies of posttransplant dialysis use. Patients supported to transplant with BiVADs appear to have posttransplant outcomes comparable to patients commonly listed as Status 2 with an isolated VAD. Compared to past analyses, there is a suggestion of improved survival with the 2018 allocation policy change.

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.

P16: Dual Continuous-Flow Ventricular Assist Devices Operation With a Single Controller: Early Assessment for Biventricular Support

Objective: The biventricular assist device (BVAD) is a treatment option for severe biventricular heart failure (BHF). For left and/or right ventricular assist device (LVAD and/or RVAD), a standalone controller unit is required for operation and control. In this work we sought to evaluate the feasibility of dual-device setup using continuous-flow (CF) universal ventricular assist device (UVAD, Fig. 1A) operation using a single controller unit. Methods: Two pneumatic pumps (Abiomed AB5000™, Danvers, MA, USA incorporated into the biventricular circulatory mock loop were used for simulation) driven by a dual-output driver (Thoratec Model 2600, Pleasanton, CA, USA) were used to simulate the left and right heart failure conditions. Systolic BHF conditions were simulated and two UVAD configurations (LVAD - primary controller mode, RVAD - secondary controller mode, set at 80% of LVAD work) were tested at various speeds for performance. Custom user interface software was developed to enable intuitive control and monitoring of the device (Fig. 1B). Results: The hemodynamic requirements were met in both RVAD and LVAD arrangement (Fig. 1C,D). The LVAD flow values provided guidance for RVAD control. In all simulated BHF conditions, both LVAD and RVAD (UVADs) provided optimal performance and demonstrated stable hemodynamics. Conclusion: The feasibility of a single controller system architecture for dual CF device operation has been shown. Both UVAD’s demonstrated optimal performance and communication for dual-device support configurations in BHF. Future direction should consist of technology characterization and optimizations.Figure 1. A - UVAD design; B - BVAD controller interface. Red window, LVAD (primary); Blue window, RVAD (secondary); C- LVAD performance; D –RVAD performance.

Contemporary Outcomes of Continuous-Flow Bi-Ventricular Assist Devices

Significant right ventricular failure (RVF) complicating left ventricular assist device (LVAD) placement has been reported at 10–30%. Although primarily indicated for left ventricular failure, VADs have become utilised in a biventricular set up to combat right ventricular failure (RVF) following LVAD implantation. With the advent of continuous flow LVADs (CF-LVADs) superseding their pulsatile predecessors, the shift towards CF-biventricular assist devices (CF-BiVADs) comes with the prospect of improved outcomes over previous pulsatile BiVADs. This study aimed to review the literature and determine the outcomes of CF-BiVAD recipients.

Anesthetic management for withdrawal from a right ventricular assist device and Fontan procedure in a patient with an implantable left ventricular assist device for fulminant cardiomyopathy

BackgroundWe herein report the anesthetic management for extracardiac conduit–total cavopulmonary connection (EC-TCPC) for weaning from an extracorporeal right ventricular assist device (RVAD) in a patient with an implantable left ventricular assist device (LVAD) for fulminant cardiomyopathy.Case presentationA 24-year-old man developed fulminant cardiomyopathy and was placed on a biventricular assist device (BiVAD) comprising an implantable LVAD and an extracorporeal RVAD. The Fontan procedure was performed to wean the patient from the RVAD and allow him to be discharged home. Atrial septal defect creation, right ventricular suture, and tricuspid valve closure were then simultaneously performed to ensure sufficient left ventricular preload to drive the LVAD. Furthermore, to keep the central venous pressure lower, the inflow cannula of the LVAD was oriented in the correct direction.ConclusionThis is the first report of anesthetic management of the Fontan procedure in a patient with a BiVAD.

Timing and Outcomes of Concurrent and Sequential Biventricular Assist Device Implantation: A Society of Thoracic Surgeons Intermacs Analysis

BackgroundBiventricular heart failure remains a clinically challenging condition to manage. Available literature describing the use of durable biventricular assist device (BiVAD) support has numerous limitations hindering the development of useful treatment algorithms. Analysis of BiVAD use within a large multicenter data set is needed to clarify outcomes associated with this therapy. MethodsThe Society of Thoracic Surgeons Intermacs database was queried to identify adults aged ≥18 years who received durable circulatory support from January 1, 2010, to December 31, 2220. The data set was divided into the following cohorts: (1) left ventricular assist device (LVAD) only (n = 27,325), (2) LVAD and concurrent right ventricular assist device (RVAD) (n = 1090), and (3) LVAD and sequential RVAD (n = 556). Propensity score matching was used to compare 1-year mortality and adverse events between concurrent (n = 565) and sequential BiVADs (n = 565). ResultsOverall survival within 1 year was significantly worse for the BiVAD cohort compared with the LVAD-only cohort (12-month survival: 50.8% vs 82.6%; log-rank P < .001). In a propensity-matched cohort, patients implanted with a BiVAD concurrently had an improved survival compared with those implanted an LVAD and an RVAD sequentially (12-month survival: 55.8% vs 41.8%; log-rank P < .001). Early (<3 months) adverse event rates were higher among patients receiving sequential BiVADs for bleeding, infection, neurologic dysfunction, and renal dysfunction (P < .01). ConclusionsAfter matching for patient and disease characteristics, patients with sequential BiVAD implantation have worse outcomes than patients with concurrent BiVAD implantation.