Total Artificial Heart Implantation Research Articles

HeartMate 3 implantation with an emphasis on the biventricular configuration.

Right ventricular failure following implantation of a durable left ventricular assist device (LVAD) is a major driver of mortality. Reported survival following biventricular (BiVAD) or total artificial heart (TAH) implantation remains substantially inferior to LVAD alone. We report our outcomes with LVAD and BiVAD HeartMate 3 (HM3). Consecutive patients undergoing implantation of an HM3 LVAD between November 2014 and December 2021, at The Alfred, Australia were included in the study. Comparison was made between the BiVAD and LVAD alone groups. A total of 86 patients, 65 patients with LVAD alone and 21 in a BiVAD configuration underwent implantation. The median age of the LVAD and BiVAD groups was 56 years (Interquartile range 46-62) and 49 years (Interquartile range 37-55), respectively. By 4 years after implantation, 54% of LVAD patients and 43% of BiVAD patients had undergone cardiac transplantation. The incidence of stroke in the entire experience was 3.5% and pump thrombosis 5% (all in the RVAD). There were 14 deaths in the LVAD group and 1 in the BiVAD group. The actuarial survival for LVAD patients at 1 year was 85% and BiVAD patients at 1 year was 95%. The application of HM 3 BiVAD support in selected patients appears to offer a satisfactory solution to patients requiring biventricular support.

Prehabilitation Using a Cardiac Rehabilitation Program for a Patient With a Total Artificial Heart Prior to Heart Transplantation.

The last few decades have been marked by significant advances in mechanical cardiocirculatory support. A total artificial heart (TAH) became a viable therapeutic option for numerous patients as a bridge to heart transplantation, particularly for those in end-stage heart failure. This technology aims to address the various subsequent shortfalls of organs. This report reviews the impact of a prehabilitation on a patient with an Aeson TAH (Carmat). We assessed improvements in functional capacity and quality of life (QoL) in a newly implanted patient following standard cardiac rehabilitation as a prehabilitation program, using 6-min walk test and the Short Form-12 (SF-12) health survey, respectively. Similar functional improvements were observed over a short period of 2 wk compared with a longer protocol for patients with a heart transplant, and superior effects on QoL. The patient was successfully transplanted 5 mo after the TAH implantation. Prehabilitation of a patient with a TAH increased both their physical capacity and QoL.

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.

The total artificial heart: where have we been, where are we now, where are we going?

The incidence and prevalence of end-stage heart failure continue to rise; however, the number of donor hearts available for transplantation continues to be limited. Therefore, alternatives to transplantation, such as the use of total artificial hearts (TAH), are necessary. The long and winding road to the development and implantation of the ideal TAH remains under construction. Although efforts have been ongoing for almost a century, researchers and clinicians continue to improve currently available TAHs and design and construct new models. With mortality and morbidity rates decreasing, particularly at high-volume centers with a dedicated team and carefully selected patients, the use of TAHs as a bridge to transplantation, and even destination therapy in clinical trials, the future of TAHs is bright.

Feasibility of Outpatient Hemodialysis for Patients With Total Artificial Heart: A Case Series.

Total artificial hearts (TAH) are used in patients with end-stage heart failure as a bridge-to-transplant. AKI is a common postoperative complication associated with TAH implant. Patients requiring temporary dialysis are denied implantation of TAH due to the inability to provide outpatient (OP) dialysis in the long term. Here we discuss four cases of TAH patients from a single center who were successfully maintained on OP hemodialysis (HD). All four patients were implanted with a 70cc Syncardia TM TAH for NICM. Two patients were implanted as bridge-to-transplant (BTT); one received a heart/kidney transplant and the other received a heart transplant. Two patients were implanted as destination therapy; one was maintained on OP HD until end-of-life, and the other received a heart transplant after becoming transplant eligible. These cases confirm that OP HD is a feasible option for TAH patients with post-implant chronic renal dysfunction provided that the dialysis centers are trained and supported by the implanting program.

(1138) A Report of the First Pediatric Total Artificial Heart Implant in Canada

(1138) A Report of the First Pediatric Total Artificial Heart Implant in Canada

Hyponatremia in Stable Patients with Advanced Heart Failure: Association to Hemodynamics and Outcome

Introduction: Hyponatremia is associated with worse outcomes in patients with chronic heart failure (HF) and reduced ejection fraction (HFrEF). However, it is unclear whether the worse prognosis is driven by hemodynamic derangement and how this potentially could be associated with hyponatremia. Methods: The study included 502 patients with HFrEF evaluated for advanced HF therapies, who underwent a right heart catheterization (RHC). Hyponatremia was defined as p-Na ≤136 mmol/L. The risk of all-cause mortality and a composite endpoint including mortality, left ventricular assist device (LVAD) implantation, implantation of total artificial heart (TAH), or heart transplantation (HTx) was evaluated using Cox regression analyses and Kaplan-Meier models. Results: Included patients were predominantly men 79% and had a median age of 54 years (IQR: 43–62). A third (165) of the patients had hyponatremia. In both univariate and multivariate regression analyses, p-Na was associated with increased central venous pressure (CVP), pulmonary capillary wedge pressure (PCWP), and mean pulmonary artery pressure (mPAP) but not with cardiac index. Hyponatremia was significantly associated with the combined endpoint (HR: 1.36 [95% CI, 1.07–1.74]; p = 0.01), but not all-cause mortality in adjusted Cox models. Conclusion: In stable HFrEF patients evaluated for advanced HF therapies, lower p-Na was associated with more deranged invasive hemodynamic measurements. Hyponatremia remained significantly associated with the combined endpoint but not all-cause mortality in adjusted Cox models. The study suggests that the increased mortality associated with hyponatremia in HFrEF patients could partly be driven by hemodynamic derangement.

Uric acid in advanced heart failure: relation to central haemodynamics and outcome

ObjectiveThe role of hyperuricaemia as a prognostic maker has been established in chronic heart failure (HF) but limited information on the association between plasma uric acid (UA) levels and central...

Bioprosthetic Total Artificial Heart Implantation Does Not Induce Chronic Inflammation.

The Aeson total artificial heart (A-TAH) has been developed for patients at risk of death from biventricular failure. We aimed to assess the inflammatory status in nine subjects implanted with the A-TAH in kinetics over one year. Laboratory assessment of leukocyte counts, inflammatory cytokines assay, and peripheral blood mononuclear cell collection before and after A-TAH implantation. Leukocyte counts were not significantly modulated according to time after A-TAH implantation (coefficient of the linear mixed effect model with 95% CI, -0.05 (-0.71 to -0.61); p = 0.44). We explored inflammatory cytokine after A-TAH and did not observe, at any time, a modified profile compared to pre-implantation values (all p -values > 0.05). Finally, we compared the distribution of circulating immune cell subpopulations identified based on sequential expression patterns for multiple clusters of differentiation. None of the population explored had significant modulation during the 12-month follow-up (all p -values > 0.05). In conclusion, using a cytokine multiplex assay combined with a flow cytometry approach, we demonstrated the absence of inflammatory signals in peripheral blood over a period of 12 months following A-TAH implantation.

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.

Aortic Pulsatility Index: A New Haemodynamic Measure with Prognostic Value in Advanced Heart Failure.

Aim: To test if the newly described haemodynamic variable, aortic pulsatility index (API), predicts long-term prognosis in advanced heart failure (HF). Methods: A single-centre study on 453 HF patients (median age: 51 years; left ventricular ejection fraction [LVEF]: 19% ± 9%) referred for right heart catheterisation. API was calculated as pulse pressure/pulmonary capillary wedge pressure. Results: Log(API) correlated significantly with central venous pressure (CVP; p<0.001) and cardiac index (p<0.001) in univariable regression analysis. CVP remained associated with log(API) in a multivariable analysis including cardiac index, heart rate, log(NT-proBNP [N-terminal proB-type natriuretic peptide]), LVEF, New York Heart Association (NYHA) class III or IV and sex (p=0.01). In univariable Cox models, log(API) was a significant predictor of freedom from the combined endpoint of death, left ventricular assist device implantation, total artificial heart implantation or heart transplantation (HR 0.33; (95% CI [0.22–0.49]); p<0.001) and all-cause mortality (HR 0.56 (95% CI [0.35–0.90]); p=0.015). After adjusting for age, sex, NYHA class III or IV and estimated glomerular filtration rate in multivariable Cox models, log(API) remained a significant predictor for the combined endpoint (HR 0.33; 95% CI [0.20–0.56]; p<0.001) and all-cause mortality (HR 0.49; 95% CI [0.26–0.96]; p=0.034). Conclusion: API was strongly associated with right-sided filling pressure and independently predicted freedom from the combined endpoint and all-cause mortality.

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.

Novel Use of Pulmonary Artery Pressure Monitoring After a Total Artificial Heart Implantation

<h3>Introduction</h3> The use of total artificial heart (TAH) implantation remains of limited use in the United States for patients with biventricular heart failure. One subgroup of patients that have been supported by TAH include patients with pulmonary hypertension that are not candidates for combined heart lung transplantation. These patients are difficult to manage after TAH implantation, as right heart catheterization cannot be performed to guide post surgical therapy. <h3>Case Report</h3> GF is a 49 year old male with ischemic cardiomyopathy on a home milrinone infusion with a left ventricular thrombus, pulmonary embolism, and pulmonary sarcoidosis. He presented with shortness of breath and fatigue. Right heart catheterization demonstrated severely decreased cardiac index (1.59L/min/m2 on thermodilution and 1.68 L/min/m2 on Fick) and severe pulmonary hypertension (transpulmonary gradient 36 mmHg, pulmonary vascular resistance 10.6 Woods Units, pulmonary artery (PA) pulsatility index 1.88). Intra-aortic balloon pump was placed for support and a PA catheter was left in place for continuous hemodynamic monitoring. He continued to decline and required escalation to extracorporeal membrane oxygenation support. He was listed for a heart transplant, but due to persistent severe pulmonary hypertension and new onset bacteremia he was made inactive and the decision was made to pursue alternative mechanical support with a TAH. Since right heart catheterization cannot be performed on patients with a TAH, a pulmonary artery sensor was placed in the left pulmonary artery one day prior to TAH implantation. Postoperatively, the TAH functioned well and the PA pressures were monitored easily with a bedside sensor. Initially, PA pressures ranged from 61-70/36-47 mmHg, but with medical optimization they improved to 37-48/20-27 mmHg by postoperative week 7 and he was relisted for transplant. <h3>Summary</h3> We identified a novel use for a pulmonary artery pressure sensor in a total artificial heart patient to help guide post implantation strategies. Our patient successfully had decreased pulmonary artery pressures and advanced to heart transplant listing.

Feasibility Of Outpatient Hemodialysis For Patients With Total Artificial Heart

<h3>Introduction</h3> Total artificial hearts (TAH) are used in patients with end-stage heart failure as a bridge-to-transplant. AKI is a common post-operative complication associated with TAH implant. Patients requiring temporary dialysis are denied implantation of TAH due to the inability to provide outpatient (OP) dialysis in the long term. In most cases, patients with a TAH with renal dysfunction requiring dialysis remain hospitalized until either a heart-kidney becomes available for transplant or renal function recovers. To our knowledge, there is only one case describing a TAH patient successfully maintained on OP dialysis, and he did not survive to transplant. Here we discuss four cases from a single center who were successfully maintained on OP hemodialysis (HD) after implantation of TAH. <h3>Case Presentation</h3> All four patients were implanted with a 70cc Syncardia TAH for NICM. Two were INTERMACS profile 2 and two were profile 3. The profile 2 patients had preoperative CKD Stage III. The profile 3 patients had normal preoperative renal function<b>.</b> Age at time of implant ranged from 31-61 years; two were female and 2 were male. Average post-op hospital length of stay was 63 days. Three patients required discharge to acute rehab, and one was discharged directly home. All patients were on scheduled OP HD QMWF. The average length of service of OP HD was 185 days (ranging 75-483 days). Outcomes for each patient differed: one remains on OP HD with TAH, one died before transplant due to anoxic brain injury, one underwent orthotopic heart transplantation but did not survive to renal transplant, and one had subsequent improvement in renal function still awaiting heart transplant. <h3>Discussion</h3> Maintaining TAH patients with renal failure on OP HD can increase patient quality of life and decrease inpatient hospital burden and costs. In these four cases, one patient survived to transplant, one did not survive to transplant, one is still awaiting dual-organ transplant, and one was successfully weaned off HD as an OP. A total of 318 days of OP HD was performed among these four patients without complications. These cases confirm that OP HD is a feasible option for TAH patients with post-implant chronic renal dysfunction provided that the dialysis centers are trained and supported by the implanting program.

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.

Temporary Diverting End-Colostomy in Critically Ill Children with Severe Perianal Wound Infection.

Broad and deep perianal wounds are challenging in both adult and pediatric ICUs. These wounds, if contaminated with gastrointestinal flora, can cause invasive sepsis and death, and recovery can be prolonged. Controlling the source of infection without diverting stool from the perianal region is complicated. The option of protective colostomy is not well-known among pediatric critical care specialists, but it can help patients survive extremely complicated critical care management. These authors present three critically ill children who required temporary protective colostomy for perianal wounds because of various clinical conditions. Two patients were treated for meningococcemia, and the other had a total artificial heart implantation for dilated cardiomyopathy. There was extensive and profound tissue loss in the perianal region in the patients with meningococcemia, and the patient with cardiomyopathy had a large pressure injury. Timely, transient, protective colostomy was beneficial in these cases and facilitated the recovery of the perianal wounds. Temporary diverting colostomy should be considered as early as possible to prevent fecal transmission and accelerate perianal wound healing in children unresponsive to local debridement and critical care.

Impact of extra-corporeal life support (ECLS) cannulation strategy on outcome after durable mechanical circulation support system implantation on behalf of durable MCS after ECLS Study Group.

The literature on outcomes of patients requiring durable mechanical circulatory support (MCS) after extra-corporeal life support (ECLS) is limited. The aim of this study was to investigate the impact of preoperative ECLS cannulation on postoperative outcome after durable MCS implantation. The durable MCS after ECLS registry is a multicenter retrospective study that gathered data on consecutive patients who underwent durable MCS implantation after ECLS between January 2010 and August 2018 in eleven high volume European centers. Patients who underwent the implantation of total artificial heart, pulsatile pumps, or first-generation pumps after ECLS were excluded from the analysis. The remaining patients were divided into two groups; central ECLS group (cECLS) and peripheral ECLS group (pECLS). A 1:1 propensity score analysis was performed to identify two matched groups. The outcome of these two groups was compared. A total of 531 durable MCS after ECLS were implanted during this period. The ECLS cannulation site was peripheral in 87% (n=462) and central in 13% (n=69) of the patients. After excluding pulsatile pumps and total artificial heart patients, a total of 494 patients remained (pECLS =434 patients, cECLS =60 patients). A 1:1 propensity score analysis resulted in 2 matched groups (each 55 patients) with median age of 54 years (48-60 years) in cECLS group and 54 years (43-60 years) in pECLS group. HeartWare HVAD (Medtronic, Minneapolis, MN) was implanted in the majority of the patients (cECLS =71% vs. pECLS =76%, P=0.67). All postoperative morbidities were comparable between the groups. The thirty-day, one year and long-term survival was comparable between the groups (P=0.73). The cannulation strategy of ECLS appears to have no impact on the post-operative outcome after durable MCS implantation.

A Bridged Approach to Heart Transplantation Using ECMO and Total Artificial Heart Implantation

Purpose The rapid increase of the use of extracorporeal membrane oxygenation (ECMO) as a direct bridge to heart transplantation (HT) raises concerns. The objective of this study is to describe the outcomes after HT using a bridge-to-bridge strategy with a sequence of ECMO support followed by temporary total artificial heart (t-TAH) implantation. Methods A retrospective, multicentric analysis of 54 patients who underwent t-TAH (SynCardia) implantation following the use of an ECMO for cardiogenic shock was performed (ECMO-t-TAH group). A control group of 163 patients who underwent t-TAH implantation as a direct bridge to transplantation (t-TAH group) was used to assess the impact of this strategy. Results Fifty-four patients, averaging 47±13 years old underwent implantation of a t-TAH after 5.3±3.4 days of ECMO perfusion for cardiogenic shock. In the ECMO-t-TAH group, 20 patients (20/54,37%) died after t-TAH implantation and 57 patients (57/163,35%) died in the t-TAH group (p=0.4968). Overall, 32 patients (32/54, 59%) underwent heart transplantation in the ECMO-t-TAH group, compared to 106 patients (106/163, 65%) in the t-TAH group (p=0.4449). No significant difference in survival was observed at 6 months, 1 and 3 years after heart transplant (ECMO-t-TAH group: 94%, 87%, and 80% vs. 87%, 83%, and 76% in the t-TAH group, respectively). Deterioration of liver function tests under t-TAH was associated with increased mortality before heart transplant in both groups. Conclusion The present series suggests that sequential bridging from ECMO to t-TAH followed by heart transplantation is a viable alternative for a group of highly selected patients.

Outcomes after Heart Transplantation and Total Artificial Heart Implantation: A Multicenter Study

Outcomes after Heart Transplantation and Total Artificial Heart Implantation: A Multicenter Study

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.