Biventricular Assist Research Articles

The Cost and Length of Stay Associated with Biventricular Assist Devices in the United States (2009-2015)

The purpose of this study was to determine the national trends in utilization, mortality, cost, and length of stay (LOS) associated with implantation of biventricular assist devices (BiVADs) using the National Inpatient Sample (NIS) database. This study was a retrospective analysis of NIS from 2009 to 2015 for surgically implanted internal (n = 538) and external BiVADs (n = 727). Exploratory analyses were performed to explain the trends found in utilization, mortality, cost, and LOS. From 2009 to 2015, the utilization of all BiVADs decreased (4.8% per year, p < 0.001) driven by the decline in utilization of external BiVADs (9.4% per year, p < 0.001). Compared to external BiVADs, internal BiVADs were associated with lower mortality (45.4% vs. 59.1%, p = 0.024), but longer LOS (64.0 vs. 20.0 days, p < 0.001) and higher incidence of renal failure (85.6% vs. 74.0%, p = 0.020). During this time period, there was no significant change in mortality; however, cost and LOS associated with all BiVAD implantations increased significantly. Only those who died during hospitalization had an increase in cost (15% per year, p < 0.001) and LOS (52% per year, p = 0.002) (Figure 1). The latter trends remained significant even after controlling for complications (e.g., gastrointestinal bleed and renal failure) and co-morbidities. The decline in utilization of BiVADs between 2009 and 2015 coincided with the increase in utilization of LVADs during this time. Declining BiVAD utilization can be related to the improvement in the LVAD technology and outcomes as well as the availability of percutaneous temporary circulatory support. Although the advancement in LVAD technology has led to decrease in mortality rate and reduction in cost and LOS, BiVAD mortality remained the same over time with a rise in cost and LOS. Future studies are required to investigate optimal BiVAD configurations and strategies, as well as patient selection in order to improve mortality and reduce LOS and cost for BiVAD patients.

P6314Left- versus Bi-Ventricular Assist Device-mediated anti-HLA alloantibody induction in bridge-to-transplantation patients

Abstract Background Presence of anti-Human Leukocyte Antigen (anti-HLA) alloantibodies (allosensitization) in a heart transplantation candidate impedes the chance of finding a compatible transplant. Left Ventricular Assist Devices (LVADs) have been shown to induce allosensitization. Purpose The purpose of this study is to characterize anti-HLA allosensitization in adult patients receiving left (LVAD) versus biventricular- (BiVAD) assist devices as bridge to transplantation (BTT). Methods This study retrospectively assessed anti-HLA antibody induction in all adult patients who have received either LVAD or BiVAD as BTT at our institution. Anti-HLA alloantibody screening was performed before, and at multiple time-points after VAD implantation. Anti-HLA antibody detection was performed with a cytotoxic panel-reactive antibody (PRA) method until 2003, enzyme-linked immunoassay (ELISA) method from 2003 to 2005 and SAB assays on the Luminex platform from 2005 to 2017. Sensitization was defined either as PRA &gt;10%, or as peak anti-HLA antibody mean fluorescence intensity (MFI) values of more than 1000. Baseline characteristics and sensitization in the two patient groups were evaluated using descriptive statistics. Results Between 2003 and 2018, 154 patients were placed on VAD support at our institution as BTT. Sensitization data were available for 130 patients. Fifty five (36.6%) patients were supported with an LVAD (median age, 48 years, 26% female) and 95 (63.4%) with a BiVAD (median age, 45 years, 28% female). Twenty-five (45.4%) of the LVAD and 49 (51.2%) of the BiVAD patients were eventually transplanted (p=0.47) with an average time to transplantation 588 and 562 days respectively. Fifteen (27.2%) LVAD and 35 (36.8%) BiVAD patients died before transplantation (p=0.23) with an average time on VAD support before death 269 and 302 days respectively. Evidence of sensitization pre-VAD was found in 17.1% of the LVAD and 12.5% of the BiVAD patients (p=0.53); these percentages rose to 40.0% (p=0.001) and 43.7% (p=0.0001) respectively at 2 to 12 months post-VAD implantation. However, the post-VAD allosensitization status was not statistically different between the LVAD and the BiVAD group. Among the 25 LVAD patients who were transplanted 7 (30.4%) were sensitized immediately before transplantation, compared to 22 (46.8%) out of 49 BiVAD patients (p=0.16). Conclusion Both LVADs and BiVADs are a factor of de novo anti-HLA antibody development in adult patients after implantation. Sensitization pattern does not seem to differ between LVAD and BiVAD patients. Additionally, patients supported by LVAD or BiVAD have similar chances of finding a suitable donor heart.

A Challenging Case: Durable Biventricular Assist Device, Bleeding, Thrombosis, and a Hole

Introduction Cardiogenic shock requiring mechanical circulatory support as a bridge to recovery continues to pose challenges. For patients who are unable to be weaned off of temporary device support, durable assist devices are an option. Unfortunately, patients receiving durable biventricular ventricular assist devices (BiVADs) represent a critically ill population with high operative mortality and RVAD thrombosis rates. Case A 58 year-old male with hypertension underwent an elective laparoscopic hemicolectomy. Post-surgery, he developed chest pain. ECG showed an anterior STEMI and transthoracic echocardiogram revealed a new ejection fraction of 30% with anterolateral and lateral wall hypokinesis. Cardiac catheterization revealed a 100% occluded left anterior descending artery, which prompted percutaneous coronary intervention and intra-aortic balloon placement. Due to worsening hemodynamics, he required emergent central veno-arterial extracorporeal membrane oxygenation (VA ECMO) placement. Due to sustained ventricular fibrillation and biventricular dysfunction on VA ECMO, he underwent ECMO revision, with placement of temporary CentriMag BiVADs. After 60 days of inability to wean temporary biventricular support, durable Medtronic Heartware BiVADs were placed as bridge to transplant. One week after durable BiVAD placement, patient developed low flows on the RVAD and profound hypoxia. He was taken to operating room emergently, and was found to have RVAD thrombosis and an apical ventricular septal defect (VSD). The RVAD was replaced and the VSD was repaired. After 18-months on BiVAD support he had a successful orthotropic heart transplant and continues to do well post-transplant. Conclusion Our case demonstrates challenges associated with selecting appropriate mechanical circulatory support devices for adequate cardiovascular support and navigating potential device related complications. Frequent reassessment is necessary to impact positive outcomes in this critically ill patient population.

Harvesting the Liver From a Donor With a Biventricular Assist Device (BiVAD)—An Unexpectedly Challenging Procedure: A Case Report

BackgroundOrgan procurement from deceased donors is usually a standard procedure. Nevertheless, the performing surgeon is often confronted with demanding situations, such as atherosclerotic or aneurysmatic aortic disease or even other pathologies, which may alter the surgical steps. We report on an interesting case of solid organ harvesting from a donor with a biventricular assist device (BiVAD) due to global heart failure. Case ReportA 42-year-old male donor with a BiVAD, enlisted for heart transplantation, died of intracerebral hemorrhage. Dressing the surgical field was challenging because the extracorporal portions of all 4 tubes and the pump device rested on the donor's body, covering his whole abdomen. To ensure enough space, the pump and tubes had been covered with sterile swabs and drapes. The second surgical assistant was tasked with holding the device slightly deviated to the left and the ankle elevated at 45°, to avoid any tube kinking. The dissection of the main vessels distally was performed using the standard technique. No encirclement of the proximal aorta beneath the diaphragm was necessary, as the cardiac output could be arrested by clamping the left ventricle's outflow tube. Once the perfusion was completed, the procedure continued in the standard fashion. ConclusionSo far, the literature has no data on organ harvesting from deceased donors with BiVAD. Although such a retrieval is quite challenging and requires an experienced team, the transplantation of the corresponding organs can be performed without any further special technical problems.

Pediatric Heart Transplant Recipients Bridged with Biventricular Assist Device Have Worse One-Year Graft Survival: An Analysis of the United Network of Organ Sharing Database

Purpose Registry data report that 15-26% of pediatric patients on the heart transplant (HT) waiting list are supported with biventricular assist devices (BiVAD), with high waitlist mortality. There are little data on post-HT outcomes for this cohort. Methods The United Network for Organ Sharing (UNOS) database was queried for patients Results Of 4904 Pediatric HT recipients, patients were grouped by no VAD support (3934, 80.2%), LVAD only (736, 15%) and BiVAD (234, 4.8%). Overall graft survival analysis indicates crossing hazard rates between groups over time (Fig. 1a) with a significant difference of graft survival at 1 year post-HT, lowest for BiVAD (p Conclusion Pre-HT BiVAD support leads to worse graft survival 1 year post-HT compared to no VAD and LVAD patients, but is not constant over time with acceptable long-term survival. Further research is needed to investigate causes of decreased graft survival in the pediatric BiVAD population early post-HT.

Ventricular Arrhythmias in Patients with Biventricular Assist Devices

Purpose Ventricular arrhythmias (VAs) are common in patients after left ventricular assist device (LVAD) implant. However, literature on VA after biventricular assist device (BIVAD) placement is limited. We performed a retrospective cohort study of patients with BIVADs to evaluate the prevalence of VA and their clinical outcomes. Methods Consecutive patients who received a BIVAD between June 2014 to July 2017 at University of California San Diego were included. Patients who experienced clinically significant VA were compared to those who did not. We assessed for predictors of VA and clinical endpoints of cardiovascular events. Results Of the 13 patients who received BIVAD (16% ischemic cardiomyopathy), 9 experienced clinically significant VA. Baseline characteristics including age, ejection fraction, and duration of heart failure were similar between the two groups. A prior history of VA predicted patients with VA after BIVAD (100% vs 0%, p Conclusion Ventricular arrhythmias are common in patients with BIVADs and are associated with worse outcomes. Future work should assess whether therapies such as ablation improve the outcome of BIVAD patients with VA.

Positive Familial History Poses a Higher Risk for No Spontaneous Recovery in Patients with Peripartum Heart Failure: Left Ventricular Assist Device Implantation and Transplantation with Bromocriptine as Novel Therapeutic Options in These Patients

Purpose Peripartum cardiomyopathy (PPCM) is a rare, but serious and potentially life-threatening condition. The nursing hormone Prolactin has been hypothesized as potential pathogenic factor of PPCM. Positive family history could be a reason for genetically caused peripartum heart failure that has possibly been demasked by the physiological pregnancy stress in a subset of patients. From animal models mutations in STAT3 may be involved in these genetic forms of PPCM. Methods We have investigated and treated 9 patients with peripartum heart failure (mean age 35 ± 4.17 years). Medical and surgical therapies were evaluated in this rare entity of young female otherwise healthy patients. Genetic investigationof STAT3has been carried out. Results All patients were referred to our department with severe biventricular heart failure. A positive family history for heart failure was reported in 5 out of 9 patients. At the time of referral all women were lactating and received bromocriptine, a dopamine D2 receptor agonist, treatment (full 8 weeks only in 1 patient who had a positive familial history prior intervention). Additional medical pharmacotherapy for heart failure included ACE inhibitors, Beta-blockers, Vasodilators and Diuretics as well as Calcium Channel Sensitizer. Six patients received a biventricular Assist device (at 27 ± 30 days after child bearing), Type Berlin Heart Excor as bridging to transplantation and 6 were transplanted successfully after a median period of almost three months after delivery (bromocriptine not continued). Genetic investigation revealed an unknown mutation in bp 255 (T insertion), exon 17-1 of STAT3 in one patient who was transplanted.Two patients recovered after medical therapy (bromocriptine for 46 ± 2 days). All women and their children are alive and well 18 months after diagnosis. Conclusion The combination of bromocriptine treatment, Berlin Heart Excor and transplantation may be a novel therapeutic strategy in patients with peripartum heart failure of potential genetic origin and will need longterm follow-up studies. It is important to develop specific biomarkers and genetic tests to distinguish PPCM from genetic peripartum heart failure.

Sensorless Physiologic Control, Suction Prevention, and Flow Balancing Algorithm for Rotary Biventricular Assist Devices

Objective: Rotary biventricular assist devices (BiVAD) are mechanical pumps that are implanted in the left and right ventricles of biventricular failure patients to pump blood and provide mechanical circulatory support. The objective of this paper was to develop and test a novel sensorless control algorithm that simultaneously satisfies the objectives of providing physiologic control (BiVAD flows meet cardiac demand), preventing ventricular suction, and providing balanced left–right (systemic and pulmonary) flows without the use of implantable flow or pressure sensors in the nonlinear, time varying, and discontinuous circulatory system. Methods: The control algorithm consists of two gain-scheduled proportional–integral controllers for left and right ventricular assist devices and only requires intrinsic pump parameters (speed and power) to maintain differential pump speeds ( $\Delta $ RPM $_{L}$ and $\Delta $ RPM $_{R}$ ) above user-defined thresholds to prevent ventricular suction, and average reference pressure heads ( $\Delta \text{P}_{L}$ , $\Delta \text{P}_{R}$ ) to provide physiologic perfusion and balance left–right-sided flow rates. A model-based approach with extended Kalman and Golay–Savitzky filters was used to estimate $\Delta \text{P}_{L}$ and $\Delta \text{P}_{R}$ . Efficacy and robustness of the algorithm were evaluated in silico during simulated rest and exercise test conditions for: 1) excessive $\Delta \text{P}_{L }$ and/or $\Delta \text{P}_{R}$ setpoints; 2) rapid threefold increase in pulmonary vascular or vena caval resistances; 3) transitions from exercise to rest; and 4) ventricular fibrillation. Results and Conclusion: The proposed sensorless BiVAD algorithm successfully prevented suction, restored physiologic perfusion, and inherently maintained left–right-sided balance for all test conditions. Significance: The proposed algorithm does not require any device modification and may be integrated into current clinical BiVADs.

Choosing Between Left Ventricular Assist Devices and Biventricular Assist Devices.

Right ventricular failure following left ventricular assist devices implantation is a serious complication associated with high mortality. In patients with or at high risk of developing right ventricular failure, biventricular support is recommended. Because univentricular support is associated with high survival rates, biventricular support is often undertaken as a last resort. With the advent of newer right ventricular and biventricular systems under design and testing, better differentiation is required to ensure optimal patients care. Clear guidelines on patient selection, time of intervention and device selection are required to improve patient outcomes.

Outcome of Paracorporeal Biventricular Assist Device in INTERMACS Profile 1 and 2 Patients: A Quaternary Referral Centre Experience

Aim: Patients requiring a biventricular assist device (BiVAD) are generally critically ill in the preoperative period and these devices can buy time for native function recovery for bridging to other support, particularly in paediatric patients where donor supply is inadequate.

An Adolescent with Left Ventricular Noncompaction and Ebstein Anomaly Presenting with Advanced Heart Failure: Discharge from Hospital with a Biventricular Assist Device

An Adolescent with Left Ventricular Noncompaction and Ebstein Anomaly Presenting with Advanced Heart Failure: Discharge from Hospital with a Biventricular Assist Device

Enhancement of Hydrodynamic Properties of Blood Pump Using Multiple Pumps Based on Synchronous Magnetic Radial Coupling

Multiple pump systems are generally able to enhance pressure and flow rates through parallel and serial connections. However, the use of multiple pumps has various drawbacks, including their high power consumption, complex configuration, and large volumes. These problems make these systems unsuitable as blood pumps. To avoid these issues, we propose a new method of multiple-pump system for use with VADs (Ventricular Assist Devices) and BiVADs (Bi Ventricular Assist Devices). In particular, we focus on enhanced hydrodynamic performance through the use of a magnetic pump. The system employs synchronous magnetic radial coupling, thereby controlling up to four pumps through a single pump driver. Through serial and parallel configurations, the multiple pumps are able to extend the operating range of pressure and flow rate for use in blood pumps. The enhanced hydrodynamic performance was verified through various experimental analyses.

Anesthetic Management of Right Ventricular Assist Device Explantation in a Heart Failure Patient on Biventricular Assist Device Support

Anesthetic Management of Right Ventricular Assist Device Explantation in a Heart Failure Patient on Biventricular Assist Device Support

O27-2 - A Case of Recovery from Anthracycline-induced Cardiomyopathy with Biventricular Assist and Mitral Valve Repair

We report the clinical course of a 43-year-old woman in remission from diffuse large B-cell lymphoma after the combination chemotherapy including hydroxydaunorubicin (anthracycline), who presented in severe congestive heart failure due to anthracycline-induced cardiomyopathy 8 months after the end of chemotherapy. She was initially treated with intra-aortic balloon pumping, followed by conversion to left ventricular assist with an Abiomed AB5000 and right ventricular assist with a centrifugal pump and a membrane oxygenator due to sharp deterioration of her heart and lung functions. With intensive medical treatments during biventricular support, her cardiac and respiratory functions gradually improved, although moderate mitral regurgitation had not been spontaneously corrected with left ventricular unloading. On the 64th day on biventricular support, the patient underwent mitral valve annuloplasty to correct regurgitation using cardiopulmonary support. As an expected result, she was weaned from biventricular assist successfully 8 days after mitral surgery (on the 72nd day on the biventricular support). The patient discharged uneventfully from our hospital and survives currently at home 4 months after weaning from the ventricular assist devices. As demonstrated in this report, aggressive biventricular support and requisite valve repairs are significantly useful for recovery from severe anthracycline-induced cardiomyopathy of the patient with cancer in the last 5 years, who cannot be a recipient for heart transplantation.

Rescue Levitronix Centrimag as a bridge to decision: is it still worthwhile?

Cardiogenic shock has poor prognosis with medical management alone and/or intra-aortic balloon pump support. Levitronix Centrimag®centrifugal pump has been increasingly used to bridge patients to decision for further advanced mechanical uni- or bi-ventricular support with a view to heart transplantation on the newly implemented super-urgent recipient scheme. We sought to review our experience as a designated centre for mechanical circulatory support to investigate its role despite the emergence of percutaneously implantable miniature devices. Between April 2009 and December 2015, 98 patients in cardiogenic shock [age 41.4 ± 12.7 years; 52 (53%) male and 46 (47%) female] underwent mechanical circulatory support of whom 90 were treated with Levitronix Centrimag as a primary procedure. Diagnosis was dilated cardiomyopathy [37 (38.1%)], ischaemic cardiomyopathy [25 (25.8%)], and other [36 (36.1%)]. Main indications were cardiogenic shock or decompensated heart failure. Other indications were early graft failure following heart transplant or right ventricular failure following left ventricular assist device insertion. Levitronix support was as follows: extra corporeal membrane oxygenation [22 (24.4%) central, 26 (28.9%) peripheral], Left Ventricular Assist Device [12 (13.3%)], Right Ventricular Assist Device [5 (5.6%)], and Bi-Ventricular Assist Device [25 (27.8%)]. The average duration of support on Levitronix was 17.1 days (range 1–111). The 30-day survival was 52% (47 patients), 6-month survival was 40% (36 patients), and 12-month survival was 37.7% (34 patients). Of the surviving patients, five underwent successful orthotopic heart transplantation, one received a HeartMate II which was subsequently explanted because of myocardial recovery, and one received a HeartMate II and is currently on the transplant list. Cause of death while on support was multiorgan failure [12 (13.3%)], cardiovascular system (CVA)/Neurological [10 (11.1%)], further haemodynamic deterioration [9 (10%)], graft failure [5 (5.6%)], bleeding [4 (4.4%)], sepsis [3 (3.3%)], myocardial infarction [3 (3.3%)], right ventricular failure [3 (3.3%)], pulmonary embolism [1 (1.1%)], embolic [1 (1.1%)], respiratory failure [1 (1.1%)], influenza + rejection [1 (1.1%)], and unknown [3 (3.3%)]. Levitronix Centrimag® remains a versatile device with potential in an acute setting. Early aggressive treatment and a younger patient population may well justify its use.

Application of multiobjective neural predictive control to biventricular assistance using dual rotary blood pumps

Abstract Rotary blood pumps are used to provide mechanical circulatory support to the failing heart in patients who are ineligible or waiting for a transplant. One of the major challenges when implementing two rotary blood pumps for biventricular support is the difficulty in maintaining pulmonary and systemic circulatory volume balance. In this study, a novel multiobjective neural predictive controller (MONPC) hybridized with a preload-based Frank-Starling-like controller (PFS) has been proposed for a dual rotary blood pump biventricular assist device in two different configurations: PFSL-MONPCR and MONPCL-PFSR. The flow rate of one pump is regulated by PFS as a function of preload, while the other pump is controlled by MONPC, which is intended to meet cardiac demand, avoid pulmonary congestion and ventricular suction. A comparative assessment was performed between the proposed controllers and a Dual Independent Frank-Starling-like control system (DI-FS) as well as a constant speed controller. The numerical simulation results showed that MONPCL-PFSR helped unload the congested left ventricle while maintaining high cardiac output during exercise. In contrast, improper flow regulation by DI-FS has resulted in pulmonary congestion. During blood loss, PFSL-MONPCR delivered the lowest suction risk, as compared to the constant speed mode, which produced negative right ventricular preload. When sensor noise and time delays were introduced in the flow and end-diastolic pressure signals, the proposed controllers were able to respond with adequate robustness during the transition from rest to exercise. This study demonstrated that the proposed controllers are superior in matching the pump flow with the cardiac demand without causing hemodynamic instabilities.

(13) - Primary Biventricular Durable Ventricular Assist Devices from Experience North American Centers: A Cautionary Tale

(13) - Primary Biventricular Durable Ventricular Assist Devices from Experience North American Centers: A Cautionary Tale

Role of Echocardiography in the Management of Patients with a Biventricular Ventricular Assist Device

Role of Echocardiography in the Management of Patients with a Biventricular Ventricular Assist Device

Suspected Malignant Hyperthermia During Biventricular Assist Device Implantation in a Patient With Left Ventricular Noncompaction Cardiomyopathy

Suspected Malignant Hyperthermia During Biventricular Assist Device Implantation in a Patient With Left Ventricular Noncompaction Cardiomyopathy

Mechanical support for biventricular failure using the HeartWare (HVAD) pump

The limited availability of organs for transplant has vastly popularized implantation of left ventricular assist devices. Right ventricular failure is a continued problem with an incidence as high as 44 %, significantly decreasing survival after left ventricular assist devices (LVAD) implantation. Survival is significantly better when LVAD patients at high risk for right ventricular failure (RVF) are converted directly to biventricular assist device (BiVAD) therapy instead of LVAD with subsequent right ventricular assist device (RVAD) implantation. The options available for biventricular assistance entail a total artificial heart (TAH) or additional right-sided placement of a continuous flow/pulsatile device which could be para-corporeal or implantable. The HeartWare HVAD (HeartWare International, Framingham, MA) device in a biventricular configuration is a very attractive option. This report details experiences and techniques for implantation of the HVAD in such a configuration.