Refractory Hypotension During Implantation of a 70 mL Total Artificial Heart in a Patient With Pectus Excavatum: A Case Report.

The Syncardia total artificial heart system is the only commercially approved durable device for treating biventricular heart failure patients awaiting heart transplantation. Conventionally, the Syncardia total artificial heart system is implanted based on the distance from the anterior aspect of the 10th thoracic vertebra to the sternum and the patient's body surface area. However, this criterion does not account for chest wall musculoskeletal deformities. This case report describes a patient with a pectus excavatum who developed compression of the inferior vena cava after Syncardia total artificial heart implantation and how transesophageal echocardiography guided chest wall surgery to accommodate the total artificial heart system.

Three-month outcomes after the implantation of two HeartMate 3 devices in total artificial heart configuration.

BACKGROUND: Total artificial heart (TAH) implantation is a rarely performed procedure. Contrarily, left ventricular assist device (VAD) implantation is rather common in many centers. As transplantation is quantitatively limited cardiac replacement with artificial hearts is a viable alternative in the treatment of severe biventricular heart failure. An alternative to TAH is the implantation of two VADs in a TAH configuration. We hereby present the first multi-center study on 3-months outcomes of patients treated by cardiectomy and placement of two HeartMate 3s in a TAH configuration. METHODS: We retrospectively investigated a cohort of 15 patients that underwent HM3-TAH-implantation at three international institutions. Follow-up was 3 months after implantation. Baseline, intra- and postoperative parameters as well as survival data and adverse events were collected. RESULTS: A total of 1089 days on HM3-TAH were observed. Thirty-day survival after HM3-TAH implantation was 53% (8/15) and three month survival was 40% (6/15). The longest duration on device was 274 days. Causes of death were multi-organ failure, sepsis, and neurological adverse events. No technical complications were documented. Two patients remained on the device. Four patients (26%) were successfully bridged to transplantation. CONCLUSIONS: The implantation of two HeartMate 3s in a TAH configuration is a last resort and off-label concept in cases of extreme biventricular heart failure. In a diligently selected patient cohort, HM3-TAH implantation is a feasible method to increase the chance of survival in a severely ill patient cohort and successfully bridge patients to heart transplantation that would otherwise have died.

A bridge-to-bridge approach to heart transplantation using extracorporeal membrane oxygenation and total artificial heart.

BACKGROUND: This study aims to describe the outcomes after heart transplantation using a bridge-to-bridge strategy with a sequence of extracorporeal membrane oxygenation (ECMO) support followed by temporary total artificial heart implantation (TAH-t). METHODS: A retrospective, multicenter analysis of 54 patients who underwent TAH-t implantation following an ECMO for cardiogenic shock was performed (ECMO-TAH-t group). A control group of 163 patients who underwent TAH-t implantation as a direct bridge to transplantation (TAH-t group) was used to assess this strategy's impact on outcomes. RESULTS: Fifty-four patients, averaging 47 ± 13 year old, underwent implantation of a TAH-t after 5.3 ± 3.4 days of ECMO perfusion for cardiogenic shock. In the ECMO-TAH-t group, 20 patients (20/54%; 37%) died after TAH-t implantation and 57 patients (57/163%; 35%) died in the TAH-t group (Gray test; P = .49). The top 3 causes of death of patients on TAH-t support were multisystem organ failure (40%), sepsis (20%), and neurologic events (20%). Overall, 32 patients (32/54%; 59%) underwent heart transplantation in the ECMO-TAH-t group compared with 106 patients (106/163%, 65%) in the TAH-t group (P = .44). No significant difference in survival was observed at 6 months, 1 year, and 3 years after heart transplant (ECMO-TAH-t group: 94%, 87%, and 80% vs 87%, 83%, and 76% in the TAH-t group, respectively). Deterioration of liver function (bilirubin, aspartate transaminase, and alanine aminotransferase levels on TAH-t) was associated with increased mortality before heart transplant in both groups. CONCLUSIONS: Sequential bridging from ECMO to TAH-t followed by heart transplantation is a viable option for a group of highly selected patients.

Reversal of Total Artificial Heart Mechanical Valve Thrombosis Using Catheter-Directed Thrombolysis.

Total artificial heart is associated with increased incidence of thromboembolism, which can prove to be fatal. The presence of four metallic tilting discs increases the chances of thrombus formation and sudden obstruction of the valve in a closed position resulting in severe hemodynamic collapse. Such a condition is conventionally treated by a surgical approach for device change; however, this procedure is extremely high risk and associated with complications and poor outcomes. We describe two total artificial heart patients with sudden obstruction to the filling of the right side due to fixing of the atrioventricular valve in a closed position due to a thrombus. After a quick diagnosis by rescue transesophageal echocardiography, we successfully treated these patients with catheter-directed thrombolysis with minimal adverse outcomes. We propose a carefully weighed application of this approach in hemodynamically unstable patients too tenuous for a timely surgery and with low risk for bleeding.

Late Cardiac Tamponade 4 Years After Total Artificial Heart Implantation.

Cardiac tamponade after ventricular assist device or total artificial heart implantation can typically occur within days or weeks after surgery. This report describes the case of a woman who presented over 4 years after SynCardia 70cc total artificial heart implantation, with physiology consistent with right ventricular outflow tract obstruction. The cause was initially attributed to device membrane failure based on the device console waveform; however, during operative exploration, a large amount of proteinaceous exudate was surrounding the device and causing the obstruction. This report illustrates how tamponade can result years after device implantation, secondary to porosity of the outflow grafts.

Successful venoplasty of superior vena cava stenosis in a patient with a total artificial heart after orthotopic heart transplantation due to primary graft failure.

BACKGROUND: With the limited number of available suitable donor hearts resulting in plateaued numbers of heart transplantations, short- and long-term mechanical circulatory support devices, including the implantation of total artificial hearts (TAHs) are modalities that are increasingly being used as treatment options for patients with end-stage heart failure. The superior vena cava syndrome has been described in this context in various disease processes. We report successful venoplasty for superior vena cava syndrome in a patient with a TAH. CASE PRESENTATION: A 65-year-old man with a history of nonischemic cardiomyopathy had received a left ventricular assist device, and then 2 years later, underwent orthotopic heart transplantation using the bicaval anastomosis technique. The postprocedural course was complicated by primary graft failure, resulting in the need for implantation of a TAH. About 5 months after TAH implantation, he started to develop complications such as volume retention, swelling of the upper extremities, and was diagnosed to have a superior vena cava syndrome. The patient underwent a successful venoplasty of his superior vena cava by interventional radiology with resolution of upper body edema, normalization of renal, and liver function. CONCLUSION: Potential fatal complications caused by catheter or wire entrapment in the right-sided mechanical valve of a TAH have been reported. We describe a safe method for the treatment of superior vena cava syndrome in patients with TAH.

Results of primary biventricular support: an analysis of data from the EUROMACS registry.

OBJECTIVES: The purpose of this study was to describe pre- and postoperative data from the EUROMACS registry with regard to indications, for and survival and complication rates of patients with primary continuous flow and pulsatile biventricular long-term assist devices (BiVADs) versus total artificial hearts (TAHs) or left ventricular assist devices (LVADs) + short-term right ventricular assist device (RVAD) implants. METHODS: We investigated patients who received implants between 1 January 2011 and 21 October 2017. Clinical baseline information about comorbidities, laboratory results, medical and device therapies and echocardiographic, haemodynamic and right ventricle (RV) parameters were evaluated along with the rates of deaths and complications. RESULTS: A total of 413 of 3282 patients (12.5%) needed a biventricular pump. We investigated 37 long-term BiVADs, 342 LVAD + short-term RVAD implants and 34 TAHs. Minor differences were found in the baseline characteristics of our population, which had an overall high morbidity profile. The 1-year survival rate was 55% for patients with a continuous flow BiVAD; 52% for patients with an LVAD + short-term RVAD; 37% for patients with pulsatile BiVADs; and 36% for patients with a TAH. No statistical difference was observed among the groups. Over 50% of patients with BiVAD support were classified as INTERMACS profiles 1 and 2. The percent of patients with ambulatory heart failure (INTERMACS 4‒7) undergoing BiVAD implants was modest at <15%. No patients with a pulsatile BiVAD (n = 15) or a TAH (n = 34) were implanted as destination therapy, but 27% of the patients with continuous flow BiVADs (n = 6) and 23% of the patients with LVAD + short-term RVAD (n = 342) were implanted as 'destination'. The adverse events profile remained high, with no significant difference among pump types. The right ventricular stroke work index and right heart failure scores indicated poor RV function in all groups. After 3 months of LVAD + short-term RVAD support, 46.7% still required ongoing support, and only 18.5% were weaned from RVAD support; 33.1% died. CONCLUSIONS: The mortality rate after BiVAD support was high. Survival rates and adverse events were statistically not different among the investigated groups. In the future, composite study end points examining quality of life and adverse events beyond survival may help in shared decision-making prior to general mechanical circulatory support, particularly in patients with BiVAD implants.

Bloodstream infections in mechanical circulatory support device recipients in the International Society of Heart and Lung Transplantation Mechanically Assisted Circulation Support Registry: Epidemiology, risk factors, and mortality.

BACKGROUND: We used multicenter international data from the International Society of Heart and Lung Transplantation Mechanically Assisted Circulation Support (IMACS) registry to determine bloodstream infection (BSI) event rate, independent risk factors, and association with mortality. METHODS: Included were patients registered in IMACS from January 2013 through December 2015, assessed BSI event rate of mechanical circulatory support (MCS) and non-MCS-related BSIs, and conducted univariate and multivariate analyses between BSI with baseline characteristics and mortality. RESULTS: We documented 1,606 BSIs in 1,231 of 10,171 MCS recipients (12%), with an event rate of 2.43 BSIs/100 patient-months within 3 months after implant (early onset) and 1.03 BSIs/100 patient-months after 3 months (late onset). Of these episodes, 1,378 (85.8%) were non- MCS-related BSI. Increasing body mass index and bilirubin were independent correlates of MCS-related BSI. Independent correlates of non-MCS-related BSI included older age, higher body mass index, previous cardiac surgery, baseline chronic renal disease and dialysis, pre-implant frailty, presence of biventricular assist device, total artificial heart or right ventricular assist device, and Interagency Registry for Mechanically Assisted Circulatory Support category 1. Survival after 3 months after implant of patients who developed early-onset BSI was 56.9% at 24 months vs 77.4% in patients without early-onset BSI (p < 0.001). Early-onset BSI was an independent correlate of mortality at 3 months after implantation (hazard ratio, 2.56; 95% confidence interval, 2.09-3.15; p < 0.001). CONCLUSIONS: Early-onset BSI was associated with significantly increased 24-month mortality. More than 85% of these BSIs were not device related. There is an opportunity for infection prevention practices to decrease the BSI event rate, which may affect 24-month survival. These data can also serve as benchmarking for individual institutions.

Lumbar muscle atrophy caused by harness replacement in a chronic calf model of total artificial heart implantation.

The postoperative care of animals implanted with mechanical circulatory support devices is complex. The standard of care requires continuous monitoring of hemodynamic parameters post implant, wound care, and maintenance of the animal's well-being, but also includes controlling the animal's biomechanics under conditions of continuous restraint and harnessing. In such studies, a harness provides secure fixation of the exteriorized device driveline and pressure lines and aids animal handling (lifting, position adjustment, and assistance with standing up). Harnessing is a key element in large-animal surgery. It affects the animal's conditions, safety, and post-procedure troubleshooting and thus may drastically worsen postoperative outcomes if improperly handled. Here we report a case associated with an unplanned harness replacement in a chronic animal model implanted with the Cleveland Clinic continuous-flow total artificial heart. Inadvertent changes to the harness resulted in posture change caused by muscular atrophy of the calf's spine that had been under long-term harness support.

The Carmat Bioprosthetic Total Artificial Heart Is Associated With Early Hemostatic Recovery and no Acquired von Willebrand Syndrome in Calves.

OBJECTIVES: To determine hemostasis perturbations, including von Willebrand factor (VWF) multimers, after implantation of a new bioprosthetic and pulsatile total artificial heart (TAH). DESIGN: Preclinical study SETTING: Single-center biosurgical research laboratory. PARTICIPANTS: Female Charolais calves, 2-to-6 months old, weighing 102-to-122 kg. INTERVENTIONS: Surgical implantation of TAH through a mid-sternotomy approach. MEASUREMENTS AND MAIN RESULTS: Four of 12 calves had a support duration of several days (4, 4, 8, and 10 days), allowing for the exploration of early steps of hemostasis parameters, including prothrombin time; coagulation factor levels (II, V, VII+X, and fibrinogen); and platelet count. Multimeric analysis of VWF was performed to detect a potential loss of high-molecular weight (HMW) multimers, as previously described for continuous flow rotary blood pumps. Despite the absence of anticoagulant treatment administered in the postoperative phase, no signs of coagulation activation were detected. Indeed, after an immediate postsurgery decrease of prothrombin time, platelet count, and coagulation factor levels, most parameters returned to baseline values. HMW multimers of VWF remained stable either after initiation or during days of support. CONCLUSIONS: Coagulation parameters and platelet count recovery in the postoperative phase of the Carmat TAH (Camat SA, Velizy Villacoublay Cedex, France) implantation in calves, in the absence of anticoagulant treatment and associated with the absence of decrease in HMW multimers of VWF, is in line with early hemocompatibility that is currently being validated in human clinical studies.

Total Artificial Heart Implantation Blood Pressure Management as Resolving Treatment for Massive Hemolysis following Total Artificial Heart Implantation.

The SynCardia Total Artificial Heart (TAH) has been used for patients with biventricular failure, who cannot be managed with implantation of a left ventricular (LV) assist device. Following TAH implantation, our patient developed severe hemolysis, which could only be managed successfully by aggressive blood pressure control [Ohashi 2003; Nakata 1998].

Non-Cardiac Symptoms of Moderate to Severe Hypokalemia in a Patient with a Syncardia™ Total Artificial Heart.

The Syncardia™ total artificial heart (TAH) is an option for patients as a bridge to transplant in those who are not candidates for left ventricular assist devices (LVAD) due to right ventricular failure. Postoperative course is highly dependent on volume status and aggressive diuresis is often necessary. One complication from aggressive diuresis is hypokalemia; however, in these patients we tolerate a lower potassium level because cardiac arrhythmias are not a concern.  However, in two separate instances non-cardiac symptoms related to severe hypokalemia occurred. These symptoms included nystagmus in one patient and agitation, tremors, and having an "out-of-body" experience in the other patient. Both these patients had resolution of symptoms with potassium replacement.

Late Surgical Bleeding Following Total Artificial Heart Implantation.

INTRODUCTION: Mechanical circulatory support for heart failure, including the Total Artificial Heart (TAH, Syncardia, Tucson, AZ, USA) has increased in recent years. This report describes bleeding complications associated with the device. METHODS: A single institution prospectively maintained quality improvement database was reviewed encompassing the first year of clinical experience with the TAH. Patients who underwent TAH implantation were identified, and a review of complications and outcomes was undertaken. RESULTS: Ten patients underwent TAH implant. Four patients experienced delayed postoperative bleeding. In three patients the manifestation of bleeding was tamponade and evidenced by TAH decreased cardiac output. In two patients, at postoperative days 31 and 137, there was a partial disruption of the aortic anastomosis along the outer curvature with pseudoaneurysm formation. Both were repaired by primary suture closure, without use of cardiopulmonary bypass. There was no mortality attributable to bleeding. CONCLUSIONS: TAH patients are at risk for delayed postoperative bleeding, often manifest as an acute decrease in cardiac output. Due to pulsatility and high dP/dT, bleeding from the aortic anastomosis should be considered in the differential of a patient with low flow and/or tamponade.

Neuron-specific enolase correlates to laboratory markers of haemolysis in patients on long-term circulatory support.

OBJECTIVES: Neuron-specific enolase (NSE) is used as a diagnostic tool in neuropathies, cerebral diseases or traumata and for some tumours. Furthermore, it is also expressed by erythrocytes and platelets and has been linked to haemolysis ex vivo as a laboratory issue. Chronic haemolysis is frequently associated with mechanical circulatory support by ventricular assist device (VAD) or total artificial heart (TAH). Therefore, we compared NSE with indicators of haemolysis in VAD and TAH patients. METHODS: We included 599 data sets of 97 patients who underwent VAD or TAH implantation. NSE, haptoglobin (HAPT), haemopexin (HPX), free haemoglobin (frHB), lactate dehydrogenase activity (LDH), platelet counts and total bilirubin (TBIL) in plasma were analysed. Further, all major cerebral events were assessed. RESULTS: NSE correlated to frHB (rs = 0.553) and to LDH (rs = 0.695). An inverse correlation was found with HAPT (rs = -0.484) and HPX (rs = -0.398). Thirty-two patients suffered neurological events. Within the time frame of 1 day before to 4 days after a neurological event, correlations of NSE to HAPT (rs = -0.540) and HPX (rs = -0.611) in negative and to frHB (rs = 0.757), LDH (rs = 0.862) and TBIL (rs = 0.549) in positive direction were established (all P < 0.05). Furthermore, haemolysis was graded into three groups for severe, moderate or no or only slight haemolysis. NSE values differed correspondingly between these groups (P < 0.001). CONCLUSION: NSE correlates to laboratory parameters indicative of haemolysis in VAD and TAH patients. Our data suggest an influence of intravascular haemolysis on NSE. Therefore, the parameter should be used with caution when it is used to assess cerebral damage.

Use of bivalirudin for anticoagulation during implantation of total artificial heart.

Heparin-induced thrombocytopenia presents a challenge for anticoagulation techniques during cardiac surgery and ventricular assist device implantation. Bivalirudin is currently recommended for use during cardiopulmonary bypass for patients with heparin-induced thrombocytopenia but requires the use of special techniques to avoid blood stagnation. We report the successful use of bivalirudin during cardiopulmonary bypass for implantation of the Total Artificial Heart with late operative bleeding likely resulting from heavy cell saver use.

Successful replacement of a detached pedestal during support with Jarvik 2000.

Infection in patients supported with left ventricular assist devices (LVAD) is common and it can limit widespread implantation of mechanical assistance as destination therapy (DT). The infection-resistance power delivery system could improve longevity and quality of life. The Jarvik 2000 (Jarvik Heart, New York, NY, USA) driveline design showed a prolonged infection-free survival and a better quality of life compared to those patients supported with traditional LVAD with an abdominal cable. We report a singular driveline complication in a 71-year-old patient supported with a Jarvik 2000. A new retroauricular pedestal was successfully repositioned after the detachement of the first one.

Recurrent thrombosis after mechanical circulatory support.

The immediate complication after implantation of mechanical circulatory support (MCS) is more often bleeding than thromboembolic events. We report an unusual case of massive thrombus formation following systemic thrombolytic therapy which happened twice after implantation of MCS. Various mechanisms may contribute to this severe complication, but attention should be paid to patients who receive MCS after systemic thrombolysis because of the secondary hypercoagulability induced by this therapy.