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In patients requiring left ventricular assist device ( LVAD) support, it can be difficult to ascertain suitability for long-term mechanical support with LVAD and eventual transplantation. LVAD implantation in a shocked patient is associated with increased morbidity and mortality. Interest is growing in the utilization of extracorporeal life support ( ECLS) as a bridge-to-bridge support for these critically unwell patients. Here, we reviewed our experience with ECLS double bridging. We hypothesized that ECLS double bridging would stabilize end-organ dysfunction and reduce ventricular assist device ( VAD) implant perioperative mortality. We conducted a retrospective review of prospectively collected data for 58 consecutive patients implanted with a continuous-flow LVAD between January 2010 and December 2013 at The Alfred Hospital, Melbourne, Victoria, Australia. Twenty-three patients required ECLS support pre- LVAD while 35 patients underwent LVAD implantation without an ECLS bridge. Preoperative morbidity in the ECLS bridge group was reflected by increased postoperative intensive care duration, blood loss, blood product use, and postoperative renal failure, but without negative impact upon survival when compared with the no ECLS group. ECLS stabilization improved end-organ function pre- VAD implant with significant improvements in hepatic and renal dysfunction. This series demonstrates that the use of ECLS bridge to VAD stabilizes end-organ dysfunction and reduces VAD implant perioperative mortality from that traditionally reported in these 'crash and burn' patients. [ABSTRACT FROM AUTHOR]

Implantable left ventricular assist devices ( LVADs) have been adapted clinically for right-sided mechanical circulatory support ( RVAD). Previous studies on RVAD support have established the benefits of outflow cannula restriction and rotational speed reduction, and recent literature has focused on assessing either the degree of outflow cannula restriction required to simulate left-sided afterload, or the limitation of RVAD rotational speeds. Anecdotally, the utility of outflow cannula restriction has been questioned, with suggestion that banding may be unnecessary and may be replaced simply by varying the outflow conduit length. Furthermore, many patients have a high pulmonary vascular resistance ( PVR) at the time of ventricular assist device ( VAD) insertion that reduces with pulmonary vascular bed remodeling. It is therefore important to assess the potential changes in flow through an RVAD as PVR changes. In this in vitro study, we observed the use of dual Heart Ware HVAD devices ( Heart Ware Inc., Framingham, MA, USA) in biventricular support ( BiVAD) configuration. We assessed the pumps' ability to maintain hemodynamic stability with and without banding; and with varying outflow cannulae length (20, 40, and 60 cm). Increased length of the outflow conduit was found to produce significantly increased afterload to the device, but this was not found to be necessary to maintain the device within the manufacturer's recommended operational parameters under a simulated normal physiological setting of mild and severe right ventricular ( RV) failure. We hypothesize that 40 cm of outflow conduit, laid down along the diaphragm and then up over the RV to reach the pulmonary trunk, will generate sufficient resistance to maintain normal pump function. [ABSTRACT FROM AUTHOR]

The European Registry for Patients with Mechanical Circulatory Support (EUROMACS) was founded on 10 December 2009 with the initiative of Roland Hetzer (Deutsches Herzzentrum Berlin, Berlin, Germany) and Jan Gummert (Herz- und Diabeteszentrum Nordrhein-Westfalen, Bad Oeynhausen, Germany) with 15 other founding international members. It aims to promote scientific research to improve care of end-stage heart failure patients with ventricular assist device or a total artificial heart as long-term mechanical circulatory support. Likewise, the organization aims to provide and maintain a registry of device implantation data and long-term follow-up of patients with mechanical circulatory support. Hence, EUROMACS affiliated itself with Dendrite Clinical Systems Ltd to offer its members a software tool that allows input and analysis of patient clinical data on a daily basis. EUROMACS facilitates further scientific studies by offering research groups access to any available data wherein patients and centres are anonymized. Furthermore, EUROMACS aims to stimulate cooperation with clinical and research institutions and with peer associations involved to further its aims. EUROMACS is the only European-based Registry for Patients with Mechanical Circulatory Support with rapid increase in institutional and individual membership. Because of the expeditious data input, the European Association for Cardiothoracic Surgeons saw the need to optimize the data availability and the significance of the registry to improve care of patients withmechanical circulatory support and its potential contribution to scientific intents; hence, the beginning of their alliance in 2012. This first annual report is designed to provide an overview of EUROMACS' structure, its activities, a first data collection and an insight to its scientific contributions. [ABSTRACT FROM AUTHOR]

Dual rotary left ventricular assist devices ( LVADs) have been used clinically to support patients with biventricular failure. However, due to the lower vascular resistance in the pulmonary circulation compared with its systemic counterpart, excessively high pulmonary flow rates are expected if the right ventricular assist device ( RVAD) is operated at its design LVAD speed. Three possible approaches are available to match the LVAD to the pulmonary circulation: operating the RVAD at a lower speed than the LVAD (mode 1), operating both pumps at their design speeds (mode 2) while relying on the cardiovascular system to adapt, and operating both pumps at their design speeds while restricting the diameter of the RVAD outflow graft (mode 3). In this study, each mode was characterized using in vitro and in vivo models of biventricular heart failure supported with two Ventr Assist LVADs. The effect of each mode on arterial and atrial pressures and flow rates for low, medium, and high vascular resistances and three different contractility levels were evaluated. The amount of speed/diameter adjustment required to accommodate elevated pulmonary vascular resistance ( PVR) during support with mode 3 was then investigated. Mode 1 required relatively low systemic vascular resistance to achieve arterial pressures less than 100 mm Hg in vitro, resulting in flow rates greater than 6 L/min. Mode 2 resulted in left atrial pressures above 25 mm Hg, unless left heart contractility was near-normal. In vitro, mode 3 resulted in expected arterial pressures and flow rates with an RVAD outflow diameter of 6.5 mm. In contrast, all modes were achievable in vivo, primarily due to higher RVAD outflow graft resistance (more than 500 dyn·s/cm5), caused by longer cannula. Flow rates could be maintained during instances of elevated PVR by increasing the RVAD speed or expanding the outflow graft diameter using an externally applied variable graft occlusion device. In conclusion, suitable hemodynamics could be produced by either restricting or not restricting the right outflow graft diameter; however, the latter required an operation of the RVAD at lower than design speed. Adjustments in outflow restriction and/or RVAD speed are recommended to accommodate varying PVR. [ABSTRACT FROM AUTHOR]

Dual rotary left ventricular assist devices ( LVADs) can provide biventricular mechanical support during heart failure. Coordination of left and right pump speeds is critical not only to avoid ventricular suction and to match cardiac output with demand, but also to ensure balanced systemic and pulmonary circulatory volumes. Physiological control systems for dual LVADs must meet these objectives across a variety of clinical scenarios by automatically adjusting left and right pump speeds to avoid catastrophic physiological consequences. In this study we evaluate a novel master/slave physiological control system for dual LVADs. The master controller is a Starling-like controller, which sets flow rate as a function of end-diastolic ventricular pressure ( EDP). The slave controller then maintains a linear relationship between right and left EDPs. Both left/right and right/left master/slave combinations were evaluated by subjecting them to four clinical scenarios (rest, postural change, Valsalva maneuver, and exercise) simulated in a mock circulation loop. The controller's performance was compared to constant-rotational-speed control and two other dual LVAD control systems: dual constant inlet pressure and dual Frank-Starling control. The results showed that the master/slave physiological control system produced fewer suction events than constant-speed control (6 vs. 62 over a 7-min period). Left/right master/slave control had lower risk of pulmonary congestion than the other control systems, as indicated by lower maximum EDPs (15.1 vs. 25.2-28.4 mm Hg). During exercise, master/slave control increased total flow from 5.2 to 10.1 L/min, primarily due to an increase of left and right pump speed. Use of the left pump as the master resulted in fewer suction events and lower EDPs than when the right pump was master. Based on these results, master/slave control using the left pump as the master automatically adjusts pump speed to avoid suction and increases pump flow during exercise without causing pulmonary venous congestion. [ABSTRACT FROM AUTHOR]

The Pedi Pump was implanted in six healthy lambs (mean 25.6 ± 1.4 kg) between the left ventricular apex and the descending aorta to evaluate in vivo performance for up to 30 days. Anticoagulation was achieved by continuous heparin infusion. Three animals were euthanized prematurely, two because of respiratory dysfunction and one because of deteriorating pump performance resulting from thrombus formation inside the pump. Three lambs were electively sacrificed 30 days after implantation; all had stable hemodynamics and minimal hemolysis, as indicated by low plasma free hemoglobin (2.5 ± 3.1 mg/ dL). Mean 30-day pump flow was 1.8 ± 0.1 L/min at a pump speed of 12 200 ± 400 rpm. Neither activated clotting time nor activated partial thromboplastin time followed the changes in heparin dose. At necropsy, depositions were observed at the front ( n = 1) and rear rotor axial positioning stops ( n = 4); improved polishing techniques on the stationary stop surfaces and the addition of a hard-carbon, thin-film coating on the rotating stop of the pumps used for the last two experiments addressed the deposition seen earlier. In conclusion, the Pedi Pump showed excellent hydraulic performance and minimal hemolysis during support for up to 30 days. Depositions observed at the axial positioning stops in earlier experiments were addressed by design and material refinements. We continue to focus on developing effective anticoagulation management in the lamb model as well as on further evaluating and demonstrating pump biocompatibility. [ABSTRACT FROM AUTHOR]

A patient with a Jarvik 2000 (Jarvik Heart, Inc., New York, NY) biventricular assist device had massive hemolysis and device insufficiency of the right ventricular assist device (RVAD) after the anticoagulation was temporarily reversed due to cerebral hemorrhage. After the patient's condition was stabilized by bridge use of CentriMag (Levitronix LLC, Waltham, MA) for right ventricle support, the Jarvik 2000 pumps with pin-shaped bearings were exchanged with new conical bearing pumps. Examination of the removed pumps revealed tight thrombus formation around the pin-shaped bearings. [ABSTRACT FROM AUTHOR]

Rotary ventricular assist device (VAD) support of the cardiovascular system is susceptible to suction events due to the limited preload sensitivity of these devices. This may be of particular concern with rotary biventricular support (BiVAD) where the native, flow balancing Starling response is diminished in both ventricles. The reliability of sensor and sensorless-based control systems which aim to control VAD flow based on preload has limitations, and, thus, an alternative solution is desired. This study introduces a compliant inflow cannula (CIC) which could improve the preload sensitivity of a rotary VAD by passively altering VAD flow depending on preload. To evaluate the design, both the CIC and a standard rigid inflow cannula were inserted into a mock circulation loop to enable biventricular heart failure support using configurations of atrial and ventricular inflow, and arterial outflow cannulation. A range of left (LVAD) and right VAD (RVAD) rotational speeds were tested as well as step changes in systemic/pulmonary vascular resistance to alter relative preloads, with resulting flow rates recorded. Simulated suction events were observed, particularly at higher VAD speeds, during support with the rigid inflow cannula, while the CIC prevented suction events under all circumstances. The compliant section passively restricted its internal diameter as preload was reduced, which increased the VAD circuit resistance and thus reduced VAD flow. Therefore, a CIC could potentially be used as a passive control system to prevent suction events in rotary left, right, and biventricular support. [ABSTRACT FROM AUTHOR]

Background: Prior studies have identified risk factors for survival in patients with end-stage heart failure (HF) requiring left ventricular assist device (LVAD) support. However, patients with biventricular HF may represent a unique cohort. Methods: We retrospectively evaluated a consecutive cohort of 113 adult, end-stage HF patients at University of California Los Angeles Medical Center who required BIVAD support between 2000 and 2009. Results: Survival to transplant was 66.4%, with 1-year actuarial survival of 62.8%. All patients were Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) Level 1 or 2 and received Thoratec (Pleasanton, CA) paracorporeal BIVAD as a bridge to transplant. Univariate analyses showed dialysis use, ventilator use, extracorporal membrane oxygenation use, low cardiac output, preserved LV ejection fraction (restrictive physiology), normal-to-high sodium, low platelet count, low total cholesterol, low high-density and high-density lipoprotein, low albumin, and elevated aspartate aminotransferase were associated with increased risk of death. We generated a scoring system for survival to transplant. Our final model, with age, sex, dialysis, cholesterol, ventilator, and albumin, gave a C-statistic of 0.870. A simplified system preserved a C-statistic of 0.844. Patients were divided into high-risk or highest-risk groups (median respective survival, 367 and 17 days), with strong discrimination between groups for death. Conclusions: We have generated a scoring system that offers high prognostic ability for patients requiring BIVAD support and hope that it may assist in clinical decision making. Further studies are needed to prospectively validate our scoring system. [ABSTRACT FROM AUTHOR]

OBJECTIVE The treatment of severe biventricular (BV) contractile failure using mechanical circulatory support is challenging. We analyzed our center’s results following implantation of a biventricular assist device (BVAD). METHODS We implanted 39 BVADs between September 2001 and January 2009. All patients were qualified candidates for heart transplantation, without an organ available at time of BVAD implantation. Fifteen patients without a history of chronic cardiomyopathy suffered from acute BV failure (group 1), whereas the other 24 suffered from severe chronic cardiomyopathy (group 2). The indication for BVAD implantation was determined in reference to echocardiography, the degree of end-organ damage, and whether the patient qualified for a heart transplant or was a candidate for bridge to recovery. RESULTS Both groups were similar regarding their preoperative hemodynamics, intraoperative and early postoperative findings, and adverse events. Patients in group 1 were younger (mean age 37 ± 17 years) than those in group 2 (51 ± 12 years). Mean duration of support in group 1 was 137 ± 109 days, and 65 ± 61 days in group 2. In group 1, 33% (5/15) were weaned off the device and 53% (8/15) underwent heart transplantation, whereas 8/24 patients (42%) in the chronic group were transplanted. Group 1’s mortality on the device was lower than that of group 2 (13% vs 67%). Furthermore, 11 patients of group 1 survived for 1 year compared with four in group 2 (73% vs 17%). CONCLUSION Implantation of a BVAD in patients with chronic heart failure and acute decompensation is associated with a high mortality and morbidity rate. By contrast, BVAD implantation can achieve excellent results in patients with acute BV failure without a history of chronic cardiomyopathy, even if they are in cardiogenic shock upon admission. [ABSTRACT FROM AUTHOR]

A 34-year-old woman with fulminant myocarditis underwent emergent implant with the Toyobo (Nipro, Osaka, Japan) paracorporeal biventricular assist device (BiVAD). The patient had been stable for 6 months, until she started to develop heart failure symptoms due to severe pulmonary insufficiency. Pulmonary valve closure and BiVAD conversion to implantable rotary pumps was performed. A DuraHeart centrifugal pump (Terumo Heart Inc, Ann Arbor, MI) was used for left ventricular assist, and a Jarvik 2000 axial-flow pump (Jarvik Heart Inc, New York, NY) was used for right ventricular assist. Although strict management was required to balance the flow rates of the 2 different types of devices, her postoperative course was uneventful and she was discharged home. [ABSTRACT FROM AUTHOR]

The increasing incidence of patients with advanced heart failure, limited donor availability, and continued advancements in the field of mechanical circulatory support have made implantation of left ventricular assist device therapy (LVAD) an attractive option for patients with end-stage heart failure. Perioperative right ventricular failure (RVF) occurs frequently in patients undergoing LVAD implantation and is associated with significant morbidity and mortality. This review will discuss the pathophysiology of RVF, recent efforts to risk-stratify patients preoperatively, and current preoperative, perioperative, and postoperative management strategies. [ABSTRACT FROM AUTHOR]

The BiVACOR is a novel rotary Biventricular Assist Device (BiVAD) undergoing development to treat global end-stage heart failure. The design includes left and right vanes positioned on a shared rotating hub to form a double-sided magnetically and hydrodynamically suspended centrifugal impeller. The performance of the device was assessed in a pulsatile mock circulation loop replicating end-stage biventricular heart failure, and was shown to restore flow from pathological (2 L/min) to normal levels (5 L/min). A novel technique to balance the left/right outflow of the BiVAD was also investigated, for which a maximum relative left to right outflow differential of 1.8 L/min was achieved at normal physiologic afterloads. The in vitro results encourage device progression to in vivo animal studies. Successful development of this BiVAD will provide a suitably miniature device for patients who require biventricular assistance. [ABSTRACT FROM AUTHOR]

A case of an echocardiographic diagnosis of biventricular assist device inflow cannula obstruction, associated with low cardiac output in a 29-years old male with dilated cardiomyopathy and severe congestive heart failure is presented. The reasons for low cardiac output in patients supported with ventricular assist devices and the role of transoesophageal echocardiography in the diagnosis of device failure are briefly discussed. [ABSTRACT FROM AUTHOR]

The New Energy and Industrial Technology Development Organization (NEDO) project was started in 1995. The goal is the development of a multipurpose, totally implantable biventricular assist device (BVAD) that can be used for any patient who suffers from severe heart failure. Our C1E3 (two-week pump) centrifugal pump, called the Gyro pump, has three design characteristics: a magnetic coupling and double pivot bearing system, an eccentric inlet port, and secondary vanes on the bottom of the impeller. The pump was miniaturized. The C1E3 evolved into the NEDO PI-601, a totally implantable centrifugal pump for BVAD. The current NEDO PI-710 pump (five-year pump) system includes a centrifugal pump with pivot bearings, a hydraulically-levitated impeller, an rpm-controlled miniaturized actuator (all-in-one actuator plus controller), an emergency clamp on the left outflow, and a Frank–Starling-type flow control. The final mass production model is now finalized, and the final animal study and two-year endurance studies are ongoing. [ABSTRACT FROM AUTHOR]

Objective: Precise timing of mechanical circulatory support as a bridge to transplantation is crucial for successful outcome. In our practice, increasing metabolic injury resulting from third organ (renal/gut) dysfunction is an indication for mechanical circulatory support. It is not known how metabolic injury would influence the outcomes in these patients. In this study we compared biochemical and clinical parameters between children who received mechanical circulatory support and those who were treated with medical management alone as a bridge to transplantation. Methods: Data from 24 patients were retrospectively analysed from their records. There were 11 patients in the mechanical group. In this group, five patients received biventricular assist device, five received veno arterial extra corporeal membrane oxygenation and one received left ventricular assist device. In the medical group, there were 13 patients who received various levels of inotropic support before transplantation. Five clinical and three biochemical parameters were identified and compared between the mechanical and medical groups. Mortality prior to transplantation was also compared between the two groups. Transplantation was the end point of the study. Results: Serum creatinine and serum lactate levels were significantly higher in the mechanical group (P=0.006 and 0.001, respectively), reflecting advanced metabolic injury in these patients. Mean fractional shortening in the mechanical group was 8.4%, compared to 14.5% in the medical group which was statistically significant (P=0.02). All of the 11 patients in the mechanical group were ventilated compared to 7 of the 13 (53.8%) in the medical group. Need for renal support was higher in the mechanical group (83.3%) in comparison to none in the medical group (P=0.023). Mortality in both groups was comparable with two patients in each group. 11 patients in the medical group (84.6%) and 9 in the mechanical group (81.8%) reached transplantation. Conclusion: This study confirmed that patients in the mechanical group were considerably worse in metabolic terms when compared to the medical group. Final outcome of bridging them to transplantation was comparable. This study seem to support the justification of reserving the mechanical circulatory support to those who are metabolically more injured without adversely affecting their outcomes. [Copyright &y& Elsevier]

Objective: Fulminant myocarditis (FM) is an uncommon but life-threatening condition for which a mechanical circulatory support (MCS) device can be life-saving. However, device selection, weaning and explantation procedures remain poorly defined. Methods: Four patients were bridged to recovery using the Thoratec® biventricular support device. All four were in a state of cardiogenic shock with rapid deterioration of their clinical status despite increasing doses of inotropes. Three patients required mechanical respiratory support, three were anuric and one was dialyzed. Echocardiography showed a mean ejection fraction of 12±8%. Results: Each Thoratec implantation was performed on cardiopulmonary bypass with a beating heart. Three patients underwent biventricular cannulation. The fourth patient underwent left ventricular and right atrial cannulation. All patients manifested evidence of moderate to severe end organ dysfunction after device implantation. However, by explantation, end organ function had recovered in all patients. After a mean duration of 17±10 days, all the patients showed evidence of myocardial recovery. Recovery was confirmed on echocardiography which showed opening of the aortic valve and contraction of both ventricles. The weaning process was performed in 2–5 days by setting the device in a fixed mode and increasing the rate. Device explantation was uneventful in the four patients. At the 6 months echocardiography follow-up, all had normal systolic function. Conclusion: In patients with FM, biventricular support allows full circulatory support and unloads both ventricles until recovery occurs. In this set of patients, weaning and removal procedures are straight-forward. These results suggest an aggressive stance toward implantation of MCS in patients with FM. [Copyright &y& Elsevier]

Approximately 10% to 15% of all patients implanted with left ventricular assist devices (LVADs) have required right heart support with another device. The necessity of aggressive biventricular support has already been proposed. Therefore, the totally implantable biventricular assist device (BVAD) was developed. The width of the BVAD main body was 87 mm, the thickness 67 mm, and the height 106 mm, while the weight was 785 g. The automatic control algorithm was developed to prevent lung edema and atrial rupture. [ABSTRACT FROM AUTHOR]

The Gyro permanently implantable (PI) pump is activated magnetically when a double pivot bearing supported impeller is rotated at predetermined revolutions per minute (rpm). The male bearing shaft of the impeller is supported by the top and bottom female pivot bearing in a loosely mated fashion. The Gyro PI pump's impeller transfers to a floating condition when the rpm is increased. The design objective of the Gyro PI pump is to drive the impeller while maintaining a top contact position to prevent thrombus formation. As a left ventricular assist device (LVAD), the Gyro PI pumps achieved long-term survivals in calves without thrombus formation. However, thrombus formation occurred during a biventricular assist device (BVAD) implantation. Our hypothesis was that the impeller remaining in the bottom contact position during the BVAD experiment caused this thrombus formation. Therefore, a replica of the Gyro PI pump housing was fabricated from a transparent plastic to observe the floating conditions of the impeller. When simulating an LVAD animal experiment, the impeller was at a non-bottom contact position. However, when simulating the BVAD animal experiment, the impeller remained at the bottom contact position. This study shows that the magnet balance affects the antithrombogenicity in a Gyro PI pump. [ABSTRACT FROM AUTHOR]

Abstract: An implantable biventricular assist device (BVAD) has been developed at Baylor College of Medicine using 2 centrifugal blood pumps. The aim of this study was to investigate the exercise-reflex response during nonpulsatile biventricular assistance and to evaluate to which degree the autoregulation of the system would accommodate the changed hemodynamic situation during physical exercise. The Baylor Gyro PI 710 BVAD has been implanted into 2 calves (strain half-Dexter) in a biventricular bypass fashion with native heart remaining. Allowing a 10 day convalescence, 2 animals were subjected to incremental exercise tests. The speed of the treadmill was increased at zero slope from 0.7 mph to 1.5 mph with increments of 0.2 mph every 3 min. During the exercise the pump flows were maintained at a fixed rate (6.93 ± 0.01 L/min for the left ventricular assist device and 5.36 ± 1.44 L/min for the right ventricular assist device). Hemodynamic parameters and pump performance were recorded continuously. The cardiac output (CO) and heart rate (HR) increased significantly during the exercise. CO increased from 11.1 ± 0.3 to 13.1 ± 0.4 L/min, and HR increased from 99 ± 7.1 to 114 ± 2.8 bpm, respectively. Mean aortic pressure, central venous pressure, and left arterial pressure did not change significantly. Also, no change was observed for the left and right pump flows. This totally implantable BVAD showed excellent long-term performance without any mechanical problems. It is feasible to operate without impairment under physical activity. However, the natural heart dominated the hemodynamic response during exercise under BVAD support. The left and the right pump flows did not increase spontaneously with exercise. We therefore conclude that a servo CO control system is necessary to regulate pump flows even during moderate exercise. [ABSTRACT FROM AUTHOR]

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Abstract: In this report, we describe an operative procedure for our implantable 1 piece biventricular assist device (BiVAD) based on a moving actuator mechanism, using an ovine model. Our implantable BiVAD is a volumetric coupled 1 piece unit including right and left blood sacs and an actuator assembly based on the moving actuator mechanism. The BiVAD was controlled by fixed rate control with 75 bpm for the most part. Both the left and the right full ejection modes with the maximum stroke angle were selected to minimize blood stasis in the blood sacs because of low assist flow condition. Three Corriedale sheep were used for the device implantation by a left thoracotomy incision. Cannulation was successfully performed in all cases. Although exposability of the right atrial appendage varied from animal to animal, the insertion of the cannula was easily performed. The cannulas were connected to the pump-actuator assembly in the preperitoneal pocket. All 3 animals survived the experimental procedure. During implantation of the device, in the 1 month survival animal, pump flow was maintained between 2.0 L/min and 2.5 L/min, mean aortic pressure was 90–110 mm Hg, and mean pulmonary artery pressure was 20–30 mm Hg. The left and right atrial pressure were maintained between 0 and 5 mm Hg. In conclusion, this ovine model for implantation of the 1 piece BiVAD can be an effective alternative for testing in vivo biocompatibility of the device although it needs more consideration for anatomical fittability for future human application. [ABSTRACT FROM AUTHOR]

Abstract: A left ventricular assist device (LVAD) is an effective method to rescue severe heart failure. Although some require a biventricular assist, the control method for the biventricular assist device (BVAD) with a rotary pump is rarely shown. The objective of this study was to investigate the strategy for controlling BVAD with rotary pumps by in vivo studies. Using 5 piglets, we set a BVAD through a left thoracotomy and made global ischemia for 30 min by clamping the base of the ascending aorta. After unclamping, the analysis of pumping performance acted for 6 h reperfusion. We set the target flow of the LVAD and set the right ventricular assist device (RVAD) speed limit as less than when the atrial collapse occurs. To detect the ventricular collapse without any specific sensor, we calculated the index of current amplitude from motor current waveform and simultaneous mean current value. In all cases, over 6 h of observation was performed, and the RVAD was weaned almost automatically. [ABSTRACT FROM AUTHOR]

Objectives: Our goal was to analyse adverse events in adolescent and adult patients with the Berlin Heart EXCOR and to assess the outcome of a subsequent heart transplant (HTX)., Methods: From 2006 to 2020, a total of 58 patients (12-64 years old) received a biventricular assist device (BIVAD) at our institution and were included in this study., Results: The causes of biventricular heart failure were nonischaemic cardiomyopathy (62.1%), ischaemic cardiomyopathy (22.4%) and myocarditis (15.5%). The median INTERMACS score was I (I-III). The median age was 49 years (interquartile range, 34-55 years), and 82.8% were male. Causes of death were multiorgan failure (25.0%), septic shock (17.9%), cerebral haemorrhage (14.3%), bleeding (14.3%) and embolic events (14.3%). Major bleeding was more frequent in the patients who died while on BIVADs (60.7 vs 6.7%, P < 0.001). Wound infections were more prevalent in HTX recipients (n = 21, 70.0%). After BIVAD thrombosis, 104 chamber exchanges were performed in 28 patients (48.3%). HTXs were performed in 52.6% of the patients after a BIVAD support time of 316 ± 240 days. The mean time to follow-up of 30 HTX recipients was 1722 ± 1368 days. One-, 6- and 12-month survival after an HTX were 96.7%, 90.0% and 76.7%, respectively. Long-term survival after 5 and 10 years was 69.7%., Conclusions: Pump thrombosis, infections and bleeding after receiving a BIVAD did not preclude a successful HTX. Although only 50% of patients with BIVADs were successfully given a transplant, long-term survival after an HTX in patients with BIVAD was noninferior compared to that of other recipients., (© The Author(s) 2022. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery.)

The long-term management of paracorporeal biventricular assist devices (BiVAD) is difficult because of significant risks of bleeding, thrombosis, and infection. Here we report the case of a 41-year-old woman with severe dilated cardiomyopathy who developed serious cerebral bleeding after receiving a paracorporeal BiVAD but recovered well after treatment. She eventually underwent cardiac transplantation 17 months after implantation of the paracorporeal BiVAD. [ABSTRACT FROM AUTHOR]