SynCardia Total Artificial Heart Research Articles

Adverse Events in Total Artificial Heart for End-Stage Heart Failure: Insight From the Food and Drug Administration Manufacturer and User Facility Device Experience (MAUDE).

Real-world clinical data, outside of clinical trials and expert centers, on adverse events related to the use of SyncCardia total artificial heart (TAH) remain limited. We aim to analyze adverse events related to the use of SynCardia TAH reported to the Food and Drug Administration (FDA)'s Manufacturers and User Defined Experience (MAUDE) database. We reviewed the FDA's MAUDE database for any adverse events involving the use of SynCardia TAH from 1/01/2012 to 9/30/2020. All the events were independently reviewed by three physicians. A total of 1,512 adverse events were identified in 453 "injury and death" reports in the MAUDE database. The most common adverse events reported were infection (20.2%) and device malfunction (20.1%). These were followed by bleeding events (16.5%), respiratory failure (10.1%), cerebrovascular accident (CVA)/other neurological dysfunction (8.7%), renal dysfunction (7.5%), hepatic dysfunction (2.2%), thromboembolic events (1.8%), pericardial effusion (1.8%), and hemolysis (1%). Death was reported in 49.4% of all the reported cases (n=224/453). The most common cause of death was multiorgan failure (n=73, 32.6%), followed by CVA/other non-specific neurological dysfunction (n=44, 19.7%), sepsis (n=24, 10.7%), withdrawal of support (n=20, 8.9%), device malfunction (n=11, 4.9%), bleeding (n=7, 3.1%), respiratory failure (n=7, 3.1%), gastrointestinal disorder (n=6, 2.7%), and cardiomyopathy (n=3, 1.3%). Infection was the most common adverse event following the implantation of TAH. Most of the deaths reported were due to multiorgan failure. Early recognition and management of any possible adverse events after the TAH implantation are essential to improve the procedural outcome and patient survival.

Current and future options for adult biventricular assistance: a review of literature.

In cardiogenic shock various short-term mechanical assistances may be employed, including an Extra Corporeal Membrane Oxygenator and other non-dischargeable devices. Once hemodynamic stabilization is achieved and the patient evolves towards a persisting biventricular dysfunction or an underlying long-standing end-stage disease is present, aside from Orthotopic Heart Transplantation, a limited number of long-term therapeutic options may be offered. So far, only the Syncardia Total Artificial Heart and the Berlin Heart EXCOR (which is not approved for adult use in the United States unlike in Europe) are available for extensive implantation. In addition to this, the strategy providing two continuous-flow Left Ventricular Assist Devices is still off-label despite its widespread use. Nevertheless, every solution ensures at best a 70% survival rate (reflecting both the severity of the condition and the limits of mechanical support) with patients suffering from heavy complications and a poor quality of life. The aim of the present paper is to summarize the features, implantation techniques, and results of current devices used for adult Biventricular Mechanical Circulatory Support, as well as a glance to future options.

The Future of Biventricular Mechanical Circulatory Support

Durable mechanical circulatory support is increasingly being utilised for patients with end-stage heart failure, with good long-term outcomes. However, the options for durable biventricular support remain limited, with the SynCardia total artificial heart being the only world-wide approved device, albeit with well documented limitations. This abstract discusses animal work with two upcoming durable biventricular assist devices.

HeartMate-3 Ventricular Assist Devices Versus the Total Artificial Heart for Biventricular Support: A Single-Center Series.

The SynCardia total artificial heart (TAH) is the only device approved for biventricular support. Continuous flow ventricular assist devices (VAD) in a biventricular configuration (BiVAD) have been used with variable results. The purpose of this report was to examine differences in patient characteristics and outcomes between two HeartMate-3 (HM-3) VADs in comparison with TAH support. All patients who received durable biventricular mechanical support from November 2018 to May 2022 at The Mount Sinai Hospital (New York) were considered. Baseline clinical, echocardiographic, hemodynamic, and outcome data were extracted. Primary outcomes were postoperative survival and successful bridge-to-transplant (BTT). A total of 16 patients received durable biventricular mechanical support during the study period, of which 6 (38%) patients received two HM-3 VAD pumps as BiVAD support and 10 (62%) patients received a TAH. Overall, TAH patients had a lower median lactate ( p < 0.05) at baseline compared to those on HM-3 BiVAD support yet had higher operative morbidity, lower 6-month survival ( p < 0.05), and a higher rate of renal failure (80 vs . 17%; p = 0.03). However, survival declined to the same rate at 1 year (50%) and was largely because of extracardiac adverse events related to underlying comorbidities (particularly, renal failure and diabetes, p < 0.05). Successful BTT was achieved in 3 out of 6 HM-3 BiVAD patients and in 5 out of 10 TAH patients. In our single center experience, similar outcomes were observed among patients BTT with HM-3 BiVAD compared to those BTT on TAH support despite lower Interagency Registry for Mechanically Assisted Circulatory Support level.

Experience With SynCardia Total Artificial Heart as a Bridge to Transplantation in 100 Patients

BackgroundThe SynCardia temporary total artificial heart (TAH-t) is an effective bridge to transplantation for patients with severe biventricular failure. However, granular single-center data from high-volume centers are lacking. We report our experience with the first 100 TAH-t recipients. MethodsA prospective institutional database was used to identify 100 patients who underwent 101 TAH-t implantations between 2012 and 2022. Patients were stratified and compared according to Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) profile 1 vs 2 or greater. Median follow-up on device support was 94 days (interquartile range, 33-276), and median follow-up after transplantation was 4.6 years (interquartile range, 2.1-6.0). ResultsOverall, 61 patients (61%) were successfully bridged to transplantation and 39 (39%) died on TAH-t support. Successful bridge rates between INTERMACS profile 1 and INTERMACS profile 2 or greater patients were similar (55.6% [95% CI, 40.4%-68.3%] vs 67.4% [95% CI, 50.5%-79.6%], respectively; P = .50). The most common adverse events (rates per 100 patient-months) on TAH-t support included infection (15.8), ischemic stroke (4.6), reoperation for mediastinal bleeding (3.5), and gastrointestinal bleeding requiring intervention (4.3). The most common cause of death on TAH-t support was multisystem organ failure (n = 20, 52.6%). Thirty-day survival after transplantation was 96.7%; survival at 6 months, 1 year, and 5 years after transplantation was 95.1% (95% CI, 85.4%-98.4%), 86.6% (95% CI, 74.9%-93.0%), and 77.5% (95% CI, 64.2%-86.3%), respectively. ConclusionsAcceptable outcomes can be achieved in the highest acuity patients using the TAH-t as a bridge to heart transplantation.

Abstract 15813: Comparative Case Series of Biventricular Support Between Heartmate-3 Ventricular Assist Devices and the Total Artificial Heart: A Single-Center Experience

Introduction: Currently, only the Syncardia Total Artificial Heart (TAH) is approved for biventricular support as a bridge-to-transplant (BTT). The off-label use of continuous flow ventricular assist devices (VAD) in a biventricular configuration (BiVAD) has been used with variable results, emphasizing the need for patient selection. We report our single-center BiVAD experience in patients supported with two HeartMate-3 (HM-3) VADs in a biventricular configuration in comparison with TAH support. Methods: All patients receiving durable biventricular mechanical support at The Mount Sinai Hospital (New York, New York) were considered. Baseline clinical, echocardiographic, hemodynamic and outcome data were extracted. Outcomes of interest were postoperative survival and adverse events, and compared using non-parametric statistics. Successful BTT and post-transplant survival were descriptively evaluated. Results: From November 2018 through May 2022, a total of 6 (37.5%) patients received two HM-3 VAD pumps in a BiVAD configuration and 10 (62.5%) patients received a TAH. Overall, TAH patients had significantly higher median INTERMACS profiles (p &lt; 0.05) at baseline compared to those on HM-3 BiVAD support but lower 30-day and 6-month survival and with a significantly higher rate of renal failure (Table 1). However, survival declined to the same rate at 1-year with both forms of support and was largely due to extracardiac adverse events related to underlying comorbidities (particularly, CKD/ESRD and diabetes, p &lt; 0.05). Successful BTT has thus far been achieved in 2 (33%) HM-3 BiVAD compared to 5 (50%) TAH patients, and had similar post-transplant survival at 1-year. Conclusions: HM-3 BiVAD demonstrated lower short-term and similar long-term mortality compared to TAH support among patients in extremis. However, larger studies are needed to optimize patient selection and pursuit of mechanical support in biventricular failure.

Total artificial heart as a bridge to transplantation.

Since the first implantation of a total artificial heart (TAH) 50 years ago the devices and technique have evolved to provide reliable support for patients with biventricular failure as a bridge to heart transplant. The purpose of this review is to discuss the history and evolution of devices, current devices, critical aspects of patient selection, tips and pitfalls of implantation, and future directions. The most studied device on the market is the SynCardia TAH, which has been implanted in over 2000 patients worldwide and is the only device that is currently Food and Drug Administration approved as a bridge to transplant. The overall survival in patients supported by the device at 1 year is 42% while those that make it to transplant have a 1 year post transplant survival of 83%. A newer device the Aeson TAH (Carmat, Velizy-Villacoublay, France) was first implanted in France in 2013 and is currently under clinical trial in the United States. Significant progress has been made in both the technology and technique of TAH implantation and these devices remain both a reliable and sometimes only option for patients with severe biventricular heart failure.

P72: Fully Coupled Computational Simulation of the Syncardia Total Artificial Heart May Optimize Clinical Performance

Background: The Syncardia Total Artificial Heart (TAH) is used as a bridge to transplant for patients with biventricular heart failure and currently the only FDA approved TAH. There is a dearth in studies investigating its mechanics, hemodynamics, and optimal performance. Previous studies have provided limited characterization of Syncardia’s dynamics with respect to platelet activation but did not fully realize a complete dynamic coupled solution. Thus, there is a knowledge gap with regards to understanding the operational capacity and performance characteristics of the TAH. The objective of this study is to characterize the hemodynamic performance of the Syncardia TAH to optimize operational parameters and further understand why the device is an effective bridge to transplant. Methods: COMSOL Multiphysics (COMSOL Inc.) was used to conduct fully coupled fluid-structure interaction simulations of the device in standard operation. The computational model contained a blood fluid volume within Syncardia’s housing assembly (ventricle), segmented polyurethane solution (SPUS) diaphragm chamber filled with air, and SynHall valves in the mitral and aortic positions. These components’ coupled physics allow for the cohesive motion of the blood volume, diaphragm, and valves by solving the fluid Navier-Stokes and solid motion equations. Results: Figure 1C is flow patterning representative of the left ventricular diastolic filling with the development of the ventricular vortex present within diastole. Negative pressure collapses and deforms the diaphragm as shown in Figure 1D to drive filling during diastole. Figure 1E shows regional stress on the SynHall mitral valve during diastole. Conclusions: We utilized a fully coupled model of the Syncardia to study hemodynamic properties including vorticity and shear stress spatial and temporal distributions. Future work will be to perform failure mode analysis to identify parameters that are associated with thrombosis as well as optimize clinical operational parameters including device setting and associated clinical management.

Total artificial heart implantation as a bridge to transplantation in the United States

ObjectivesAlthough the SynCardia total artificial heart (SynCardia Systems, LLC) was approved for use as a bridge to transplantation in 2004 in the United States, most centers do not adopt the total artificial heart as a standard bridging strategy for patients with biventricular failure. This study was designed to characterize the current use and outcomes of patients placed on total artificial heart support. MethodsThe United Network of Organ Sharing Standard Transplant Research File was queried to identify total artificial heart implantation in the United States between 2005 and 2018. Multivariable Cox regression models were used for risk prediction. ResultsA total of 471 patients (mean age, 49 years; standard deviation, 13 years; 88% were male) underwent total artificial heart implantation. Of 161 transplant centers, 11 centers had cumulative volume of 10 or more implants. The 6-month cumulative incidence of mortality on the total artificial heart was 24.6%. The 6-month cumulative incidence of transplant was 49.0%. The 1-year mortality post-transplantation was 20.0%. Cumulative center volume less than 10 implants was predictive of both mortality on the total artificial heart (hazard ratio, 2.2, 95% confidence interval, 1.5-3.1, P < .001) and post-transplant mortality after a total artificial heart bridge (hazard ratio, 1.5, 95% confidence interval, 1.0-2.2, P = .039). ConclusionsTotal artificial heart use is low, but the total artificial heart can be an option for biventricular bridge to transplant with acceptable bridge to transplant and post-transplant survival, especially in higher-volume centers. The observation of inferior outcomes in lower-volume centers raises questions as to whether targeted training, center certifications, and minimum volume requirements could improve outcomes for patients requiring the total artificial heart.

Trends and outcomes following total artificial heart as bridge to transplant from the UNOS database.

Bridge to transplantation (BTT) with a SynCardia Total Artificial Heart (TAH) has been gaining momentum as a therapy for patients with biventricular heart failure. Recent transplant waitlist and posttransplant outcomes with this strategy have not been comprehensively characterized. We reviewed the United Network for Organ Sharing (UNOS) database to examine BTT outcomes for the TAH system since approval. Adult patients listed for heart transplantation in the UNOS system between 2004 and 2020 who underwent BTT therapy with a TAH were included in the study. Trends in utilization of TAH compared with other durable mechanical support strategies were examined. The primary outcome was 1-year survival following heart transplantation following BTT with TAH. Secondary outcomes included waitlist deterioration and risk factors for waitlist or posttransplant mortality. During the study 433 total patients underwent TAH implant as BTT therapy; 236 (54.4%) were listed with the TAH, while the remaining patients were upgraded to TAH support while on the waitlist. Waitlist mortality was 7.4%, with 375 patients (86.6%) ultimately being transplanted. Age, cerebrovascular disease, functional status, and ventilator dependence were risk factors for waitlist mortality. One-year survival following successful BTT was 80%. Risk factors for mortality following BTT included age, body mass index, and underlying diagnosis. Patients undergoing BTT with TAH demonstrate acceptable waitlist survival and good 1-year survival. While utilization initially increased as a BTT therapy, there has been a plateau in relative utilization. Individual patient and transplantation center factors deserve further investigation to determine the ideal population for this therapy.

Anticoagulation in syncardia total artificial heart recipients: anti-factor Xa or activated partial thromboplastin time?

Although the activated partial thromboplastin time (aPTT) has historically been the method of choice for anticoagulation monitoring in patients undergoing mechanical circulatory support with intravenous unfractionated heparin, it is being progressively superseded by the anti-factor Xa (anti-Xa) method. A retrospective single-arm, single-centre analysis of 20 patients who underwent total artificial heart implantation entailed simultaneous determinations of aPTT and anti-Xa. Agreement between these parameters was assessed using the Bland–Altman method. Despite a positive correlation between aPTT and anti-Xa, normal target ranges were poorly aligned: from 5th to 30th postoperative day, for anti-Xa values of 0.2 and 0.4 U/ml corresponding aPTT values were 52.1 and 65.2 s, 7.9 and 14.8 lower than predicted values, respectively. This was not associated with thromboembolic sequalae. It was not possible to demonstrate a significant relationship between the predictor variables (postoperative day; white blood cell count; C-reactive protein concentration; alanine transaminase and alkaline phosphatase level; bilirubin; haemoglobin; albumin and total protein concentration) and the agreement between aPTT and anti-Xa levels. In summary, when anti-Xa levels were used to guide anticoagulation therapy, corresponding aPTT levels were low with respect to target range. Methodology applied in this study is generalizable to other forms of mechanical circulatory support.

Total Artificial Heart Update

The SynCardia Total Artificial Heart (TAH, SynCardia Systems, Tucson, AZ) is the only biventricular cardiac replacement approved for bridge to transplantation by the U.S. Food and Drug Administration (FDA) and which carries the European Union CE mark. It has been implanted in about 2000 patients. In experienced centers, 60 to 80 % of implanted patients have been transplanted and over 80 % of those transplanted have lived for over 1 year. The SynCardia TAH has supported potential cardiac recipients with irreversible biventricular failure for up to 6 years, providing physiologic pulsatile flows of 6 to 8 L/min at filling pressures of less than 10 mmHg allowing for optimal perfusion and recovery of organs such as the kidneys and liver. It is a tested device that provides a method for recovering potential transplant candidates who rapidly decompensate from biventricular failure or who have chronic cardiac failure from a variety of etiologies. This article covers the history, mechanical function and monitoring, implantation, patient selection and management, and outpatient use. It also reviews outcome data from the original FDA study as well as contemporary data from experienced centers.

In-vitro performance of a single-chambered total artificial heart in a Fontan circulation

An in-vitro study was conducted to investigate the general feasibility of using only one pumping chamber of the SynCardia total artificial heart (TAH) as a replacement of the single ventricle palliated by Fontan circulation. A mock circulation loop was used to mimic a Fontan circulation. The combination of both ventricle sizes (50 and 70 cc) and driver (Freedom Driver and Companion C2 Driver) was investigated. Two clinical relevant scenarios (early Fontan; late Fontan) as derived from literature data were set up in the mock loop. The impact of increased transpulmonary pressure gradient, low atrial pressure, and raised central venous pressure on cardiac output was studied. From a hemodynamic point, the single-chambered TAH performed sufficiently in the setting of the Fontan circulation. Increased transpulmonary pressure gradient, from ideal to pulmonary hypertension, decreased the blood flow in combinations by almost 2 L/min. In the early Fontan scenario, a cardiac output of 3–3.5 L/min was achieved using the 50 cc ventricle, driven by the Companion C2 Driver. Even under pulmonary hypertension, cardiac outputs greater than 4 L/min could be obtained with the 70 cc pump chamber in the late Fontan scenario. In the clinically relevant Fontan scenarios, implementation of the single chambered TAH performed successfully from a hemodynamic point of view. The replacement of the failing univentricular heart by a single chamber of the SynCardia TAH may provide an alternative to a complex biventricular repair procedure or ventricular support in Fontan patients.

Agreement between Anti-Factor Xa and Activated Partial Thromboplastin Time Measurements in Syncardia Total Artificial Heart Recipients Receiving Postoperative Anticoagulation with Unfractionated Heparin

<h3>Purpose</h3> The Activated Partial Thromboplastin Time (aPTT) has been the historical method of choice for anticoagulation monitoring in patients undergoing mechanical circulatory support with intravenous unfractionated heparin (IVUFH). However, the assay is susceptible to interference effects and is being progressively superseded by the anti-Factor Xa (anti-Xa) method. The study aim was to investigate the agreement between aPTT and anti-Xa measurements in patients receiving post-operative anticoagulation with IVUFH following Syncardia Inc. Total Artificial Heart (TAH) implantation. <h3>Methods</h3> A retrospective single arm, single centre analysis of 20 patients who underwent TAH implantation from July 2014 to October 2018 entailed simultaneous determinations of aPTT and anti-Xa. Agreement between these parameters was assessed using a novel statistical approach based on the Bland-Altman method. <h3>Results</h3> In spite of a positive correlation between aPPT and anti-Xa measurements, normal target ranges were poorly aligned: from 5^th to 30^th post-operative day, for anti-Xa values of 0.2 and 0.4 U/mL corresponding APTT values were 51.1 and 64.3 seconds, respectively. Moreover, white blood cell count was associated with a trend towards lower aPTT levels with respect to anti-Xa. Conversely, bilirubin level was significantly associated with an increase in aPTT levels with respect to anti-Xa values. <h3>Conclusion</h3> A novel method developed to investigate the agreement between aPTT and anti-Xa in the peri-operative phase of TAH therapy showed comparatively low levels of anticoagulation (with respect to historical target aPTT range) were not associated with thromboembolic sequalae. Methodology developed for this study is generalisable to other forms of mechanical circulatory support.

Concordance between Anti-Factor Xa and Activated Partial Thromboplastin Time Measurements in Syncardia Total Artificial Heart Recipients Receiving Postoperative Anticoagulation with Unfractionated Heparin

Activated Partial Thromboplastin Time has been the method of choice for anticoagulation monitoring in patients undergoing mechanical circulatory support with intravenous unfractionated heparin (IVUFH). However, aPTT assay is relatively susceptible to interference effects and is being progressively superseded by the anti-factor Xa (anti-FXa) method. The aim of this study was to identify the determinants of the concordance between aPPT and anti-FXa measurements in Syncardia Total Artificial Heart (TAH) recipients receiving post-operative anticoagulation with IVUH. A retrospective single centre analysis of 20 patients who underwent cardiectomy and TAH implantation from July 2014 to October 2018 entailed the comparison of simultaneous aPTT and anti-FXa measurements. Concordance was assessed analysing paired samples using a novel statistical approach based on the Bland-Altman method. In spite of a positive correlation between aPPT and anti-FXa measurements, normal target ranges were poorly aligned. At anti-Xa values of 0.2 and 0.4 U/mL predicted APTT values were = 51.1 and 64.3 seconds, respectively, slightly lower than expected for in range values of aPTT. APTT was affected by increase in the white cell count showing falsely decreased results when anti-FXa was within range. We describe a novel method to guide the transition from aPTT to anti-FXa for TAH recipients which generalizable to other forms of MCS. We conclude that low levels of anticoagulation were not associated with adverse sequalae because pro-haemorrhagic effects prevail over prothrombotic effects in TAH recipients. The influence of certain markers of infection and hepatic function on concordance provide falsely low aPTT values when anti-FXa is in range.

New Approach to the Treatment of Patients in Intermac 1 or 2 Biventricular Failure and on ECMO with the Syncardia Temporary Total Artificial Heart

The objective of the present study is to review the clinical experience of 5 North American Centers with the Syncardia (temporary) Total Artificial Heart focusing on the most recent data with patients in biventricular failure and in patients staged to TAH after ECMO or temporary mechanical support devices. Access to transplantation and survival were the two most significant outcomes of the study. Moreover, we sought to determine the effect of end-organ recovery while on TAH on transplant accessibility and outcomes. The rationale for the present study is to understand how patient selection, timing of TAH implantation, the need for ECMO at the time of TAH implantation, the recovery of end-organ function during TAH support affect patient survival, accessibility to and outcomes after heart transplantation. We hypothesized that properly selected patients in Intermacs clinical status 1 and 2 with biventricular failure and patients supported on ECMO have significant survival rate after TAH implantation and after heart transplantation. Moreover, we suggest that renal and hepatic insufficiency developing in patients in Intermacs clinical status I and 2 can recover under TAH support and that these patients can eventually qualify for heart transplantation. We also believe that properly selected patients whom cannot be weaned from ECMO could benefit from TAH implantation and heart transplantation. A registry of all consecutive adult patients who received a TAH from January 2013 to June 2019 from participating centers was established and centralized at the Montreal Heart Institute. More than 200 patients are included in the study population. Descriptive statistics, Cox proportional hazard models and log-rank tests will be used to study the relationship between patient characteristics before TAH implantation and outcomes after TAH surgery and following heart transplantation. Survival to TAH implantation, to heart transplantation and after transplantation. Impact of ECMO support at the time of TAH implantation on survival and access to transplantation. Effects of pre TAH renal and hepatic insufficiency on survival after TAH implantation and after heart transplantation.

Biventricular Support with Syncardia Total Artificial Heart: Long-Term Single-Center Experience

The SynCardia Total Artificial Heart (TAH) is a pneumatically driven assist system to provide mechanical circulatory support in patients with severe non-reversible biventricular failure, who otherwise have no mechanical support devices. The aim of our retrospective study is to assess the comorbidity and survival of patients awaiting cardiac transplant while circulatory support with TAH. We examined data related to survival, adverse events, and outcomes from patients undergoing TAH implantation between Januar 2001 and September 2019. For determination of the predictors for mortality we used multivariate analysis. Between February 2001 and September 2019, a total of 190 consecutive patients (88.9% men; mean age, 53±11.6 years,) underwent TAH implantation. Indications for TAH implantation were cardiomyopathy in 84 (44.2%), acute myocardial infarction in 50 (26.3%) and postcardiotomy biventricular heart failure in 29 (15.3%) and others (allograft rejection, myocarditis, endocarditis, congenital heart disease) in 27 patients (14.2%). The majority of patients (166/87.4%) were in INTERMACS profile 1, the remainder (24/12.7%) in INTERMACS profiles 2-3. Preoperative measures of the creatinine was 2.0±1.3 mg/dl and total bilirubin 3.0±3.8 mg/dl. The median support time was 169 days (range, 1 to 971 days). During TAH support, 32.1% of patients suffered from stroke, 30.5% from mesenteric ischemia and 24.2% from gastrointestinal bleeding. The median follow-up for survival of patients on support was 4.3 months. The 1-, 6- and 12-month survival was 71%, 42% and 35%, respectively. A total of 120 (63.2%) patients died during support. The most common causes of the death were multiorgan failure or/with sepsis. Multivariate analysis revealed that age p=0.003), underweight with BMI <18.5 kg/m² (p=0.001), higher total bilirubin (p=0.007) and preoperative IABP (p=0.013) were independent predictors for mortality during support. Sixty-nine (35.3%) were successfully bridged to transplantation after a mean support time of 311±205 days. 1-, 5- and 10-year survival was 64%, 58% and 51%, respectively. SynCardia TAH provides acceptable outcomes in critically sick patients with irreversible heart failure who are candidates for cardiac transplantation. More than one third of our TAH-patients were be successfully bridged to transplantation.

Heart transplantation after SynCardia® total artificial heart implantation.

The SynCardia total artificial heart (TAH)® is the only approved TAH device. This report summarizes our single-center experience with the SynCardia TAH® with particular focus on the outcome after subsequent heart transplantation. We retrospectively analysed the outcome of all transplanted SynCardia TAH® patients at our center between 2001 and 2019 in comparison to transplanted left ventricular assist device (LVAD) and biventricular assist device (BVAD) patients and to transplanted patients without prior durable mechanical circulatory support (non-MCS). Only a fraction (n=69; 37.3%) of all SynCardia TAH® patients (n=193) were transplanted. The majority (81.2%) of those were in high-urgency status at the time of transplantation. Survival in transplanted SynCardia TAH® patients was significantly poorer when compared to LVAD-, BVAD- and non-MCS patients (P=0.008). Heart transplantation in SynCardia TAH® patients requires distinct risk stratification to improve outcomes.

Comparison of SynCardia total artificial heart and HeartWare HVAD biventricular support for management of biventricular heart failure: a systematic review and meta-analysis.

The aim of this study was to compare the outcomes of patients undergoing SynCardia total artificial heart (TAH) and biventricular HeartWare ventricular assist device (Bi-HVAD) support for biventricular heart failure (HF). Electronic search was performed to identify all relevant studies detailing patients who underwent biventricular assist device implantation using Bi-HVAD devices and those who underwent TAH placement for biventricular HF. Twelve studies including 512 patients in the TAH group versus 38 patients in the Bi-HVAD group were pooled for meta-analysis. Ischemic cardiac etiology was present in 32% (95% CI, 24-47) of TAH vs. 15% (95% CI, 4-44) of Bi-HVAD patients (P=0.21). There was a comparable incidence of stroke [TAH 11% (95% CI, 7-16) vs. Bi-HVAD 13% (95% CI, 2-51), P=0.86] and acute kidney injury [TAH 28% (95% CI, 2-89) vs. Bi-HVAD 27% (95% CI, 9-59), P=0.98]. Overall infection rate was 67% (95% CI, 47-82) in TAH and 36% (95% CI, 10-74) in Bi-HVAD (P=0.16). Driveline infections were comparable between the two groups [TAH 11% (95% CI, 6-19) vs. Bi-HVAD 8% (95% CI, 1-39), P=0.73] and although a higher incidence of mediastinitis was found in the Bi-HVAD group [TAH 4% (95% CI, 2-7) vs. Bi-HVAD 15% (95% CI, 4-45), P=0.07] there was no statistically significant difference between the groups. Postoperative bleeding was present in 42% (95% CI, 28-58) of TAH vs. 23% (95% CI, 8-52) of Bi-HVAD (P=0.22). Patients in the TAH group had shorter duration of support [TAH 71 days (95% CI, 15-127) vs. Bi-HVAD 167 days (95% CI, 116-217), P=0.01]. At the mean follow-up time of 120 days, (95% CI, 83-157) patients in both groups had similar overall mortality [TAH 36% (95% CI, 22-49) vs. Bi-HVAD 26% (95% CI, 6-46), P=0.44] including mortality on device support [TAH 26% (95% CI, 17-36) vs. Bi-HVAD 21% (95% CI, 4-37), P=0.55]. Discharge home on support was achieved in 6% (95% CI, 4-17%) of TAH patients vs. 73% (95% CI, 48-89%) of Bi-HVAD (P<0.01), and 68% (95% CI, 52-84) of TAH patients were transplanted vs. 61% (95% CI, 47-75) in the Bi-HVAD group (P=0.14). Patients on Bi-HVAD support were more likely to be able to be discharged home on support and had similar overall mortality to TAH, albeit with much longer duration of support.

Initial United Kingdom experience with the syncardia total artificial heart

Introduction The SynCardia Total Artificial Heart (TAH) is a form of mechanical circulatory support where the patient's native ventricles and valves are explanted and replaced by a pneumatically powered artificial heart (1). Implantation is indicated in patients with irreversible biventricular cardiac failure (2). We have recently initiated a TAH program at Harefield Hospital for the UK patient population. The aim of this study is to review our initial experience in terms of success rate of bridging patients to transplantation and post cardiac transplant outcomes. Methods We analysed data from all patients who received a TAH from July 2014 until April 2019 at our institution to quantify the rate of successful bridging to transplantation and the subsequent post cardiac transplant outcomes. Results 22patients (males, n = 14; mean age 39 ± 17) received TAH implants due to severe, irrecoverable biventricular failure. Aetiologies were dilated (n = 11, 50%), ischaemic (n = 6, 27%) and valvular (n = 3, 13%) cardiomyopathies. 12 patients (55%) were on veno-arterial extra corporeal membrane oxygen support with mean duration of 8.3 ± 8.6 days prior to TAH implantation. Mean duration on TAH support was 95 ± 114 days. 7 patients (32%) suffered stroke, 8 (36%) required surgical exploration for bleeding and 7 (32%) developed sepsis. 9 patients (40%) were successfully bridged to and received a heart transplant, another 3 patients are on the waiting list. 6 patients (27%) are still living: 3 post heart transplantation and 3 remain on the waiting list for a heart transplant. Discussion We have successfully introduced The TAH program in the UK as an important and unique intervention for a high risk patient population with biventricular heart failure who are not candidates for left ventricular assist device. Despite high rate of perioperative and early mortality and postoperative complications TAH implantation provides a realistic alternative for these otherwise futile cases.