Permanent Mechanical Circulatory Support Research Articles

Sepsis in cardiothoracic surgery

Sepsis is a life-changing condition that can occur in patients undergoing cardiothoracic surgery. It is characterized by a dysregulated inflammatory response to infection, often leading to higher rates of organ dysfunction and mortality. The importance of early recognition and prompt intervention in managing sepsis-related complications in cardiothoracic surgery is pivotal to adequate surgical practice. Due to the multiple subsections that construct the broad spectrum of cardiothoracic surgery, it is important to address the presence of sepsis in elective cardiothoracic surgery, urgent/emergency cardiothoracic surgery, solid organ transplantation, and both temporary and permanent mechanical circulatory support (ie, left ventricular assist devices, extracorporeal membrane oxygenation, and percutaneous temporary devices [eg, Impella series]). Exploring the incidence, prevalence, and risk factors of said subsections can lead to improvement in postoperative outcomes. The impact of accompanying infections can progress into further operative morbidity and mortality. To this effect, the perioperative management of cardiothoracic surgery transcends surgical techniques and should undergo additional recognition of other occurrences such as wound infections, bloodstream infections, urinary tract infections, and pneumonia. Sepsis remains a concern in cardiothoracic surgery, as it can lead to devastating consequences. Hence, there is an evident need for heightened vigilance, early recognition, and effective management strategies to mitigate the risk of sepsis in this patient population. The purpose of this article is to provide an overview of sepsis in the different cardiothoracic surgery areas.

How do mechanical circulatory support patients die? Autopsy findings for left-ventricular assist device/total artificial heart nonsurvivors

Although life saving for end-stage heart failure patients, permanent mechanical circulatory support (MCS) is often the proximate cause of death in those that do not survive to transplant. Autopsy remains the gold standard for diagnosing causes of death and a vital tool for better understanding underlying pathology of nonsurvivors. The aim of this study was to determine the frequency and outcomes of autopsy investigations and compare these with premortem clinical assessment. The autopsy findings and medical records of all patients who underwent left ventricular assist device (LVAD) or total artificial heart (TAH) insertion between June 1994 and April 2022 as a bridge to transplant, but subsequently died pre-heart transplantation were reviewed. A total of 203 patients had a LVAD or TAH implanted during the study period. Seventy-eight patients (M=59, F=19) died prior to transplantation (age 55 [14] years, INTERMACS=2). Autopsies were conducted in 26 of 78 patients (33%). Three were limited studies. The leading contributor to cause of death was respiratory (14/26), either nosocomial infection or associated with multiorgan failure. Intracranial hemorrhage was the second most common cause of death (8/26). There was a major discrepancy rate of 17% and a minor discrepancy rate of 43%. Autopsy study added a total of 14 additional contributors of death beyond clinical assessment alone (Graphical Abstract). Over an observational period of 26years, the frequency of autopsy was low. To improve LVAD/TAH patient survival to transplant, better understanding as to cause of death is required. Patients with MCS have complex physiology and are at high risk of infection and bleeding complications.

Outcome of Patients Supported by Large Impella Systems After Re-implantation Due to Continued or Recurrent Need of Temporary Mechanical Circulatory Support.

Despite the growing utilization of a large microaxial pump, i. e., Impella 5.0 or 5.5 (Abiomed Inc., Danvers, MA, USA) (Impella 5+) for patients with cardiogenic shock (CS), adverse events including the necessity of re-implantation have not been well discussed. In all 67 patients, in-hospital mortality was 52.2% (n = 35). Explantation of Impella 5+ was performed in 39 patients (58.2%), 22 of whom (32.8%) recovered under Impella 5+, and ten further patients (14.9%) survived after a successful transition to permanent mechanical circulatory support. Embolic events were considerable complications in each access. They occurred in the right arm after the removal of Impella 5+ via a subclavian artery (SA) (n = 3, 9.1%) or in the form of leg ischemia in patients with Impella 5+ via femoral artery (FA) (n = 2, 33.3%). Re-implantation was necessary for 10 patients (14.9%) due to 1) recurrent CS (n = 3), 2) pump thrombosis (n = 5), or 3) pump dislocation (n = 2), all of which were successfully performed via the same access route. In univariate analysis, FA access was a significant risk factor for Impella dysfunction compared to SA access (FA vs. SA, 42.9% vs. 9.8%, p < 0.05, odds ratio 6.88). No statistical difference of overall mortality was observed in patients with Impella 5+ re-implantation (n = 10) compared to patients with primary Impella 5+ support (n = 57) (80.0% (n = 8/10) vs. 47.4% (n = 27/57), p = 0.09). Our results suggested the acceptable clinical outcome of Impella 5+ despite a 15% re-implantation rate. Our observational data may merit further analysis of anticoagulation strategies, including risk stratification for embolic events.

Increased Opportunities for Transplantation for Women in the New Heart Allocation System

BackgroundHistorically, women have had less access to advanced heart failure therapies, including temporary and permanent mechanical circulatory support and heart transplantation (HT), with worse waitlist and post-transplant survival compared with men. This study evaluated for improvement in sex differences across all phases of HT in the 2018 allocation system. Methods and ResultsThe United Network for Organ Sharing registry was queried to identify adult patients (≥18 years) listed for HT from October 18, 2016, to October 17, 2018 (old allocation), and from October 18, 2018, to October 18, 2020 (new allocation). The outcomes of interest included waitlist survival, pretransplant use of temporary and durable mechanical circulatory support, rates of HT, and post-transplant survival. There were 15,629 patients who were listed for HT and included in this analysis; 7745 (2039 women, 26.3%) in the new and 7875 patients (2074 women, 26.3%) in the old allocation system. When compared with men in the new allocation system, women were more likely to have lower priority United Network for Organ Sharing status at time of transplant, and less likely to be supported by an intra-aortic balloon pump (27.1% vs 32.2%, P < .001), with no difference in the use of venoarterial extracorporeal membrane oxygenation (5.5% vs 6.3%, P = .28). Despite these findings, when transplantation was viewed in the context of risk for death or delisting, the cumulative incidence of transplant within 6 months of listing was higher in women than men in the new allocation system (62.4% vs 54.9%, P < .001) with no differences in post-transplant survival. When comparing women in the old with the new allocation system, the distance traveled for organ procurement was 187.5 ± 207.0 miles vs 272.8 ± 233.7 miles (P < .001). ConclusionsAlthough the use of temporary mechanical circulatory support in women remains lower than in men in the new allocation system, more women are being transplanted with comparable waitlist and post-transplant outcomes as men. Broader sharing may be making its greatest impact on improving transplant opportunities for women.

Is it Safe for Patients with Left Ventricular Assist Devices to Undergo Non-Cardiac Surgery?

Background and Objectives: Since the first use of ventricular assist devices (VADs) as bridge to recovery and bridge to cardiac transplantation in the early 1990s, significant technological advances have transformed VAD implantation into a routine destination therapy. With improved survival, many patients present for cardiac surgery for conditions not directly related to their permanent mechanical circulatory support. The aim of this study was to analyze the indications and outcomes of non-cardiac surgeries (NCSs) of left ventricular assist device (LVAD) patients in tertiary center. Material and Methods: We present a single-center experience after 151 LVAD implantations in 138 consecutive patients between 2012–2019 who had to undergo NCS during a follow-up period of 37 +/− 23.4 months on left ventricular assist device (LVAD). Results: A total of 105 procedures was performed in 63 LVAD recipients, resulting in peri-operative mortality of 3.8%. Twenty-five (39.7%) of patients underwent multiple surgeries. We found no significant difference in cumulative survival associated with the performed surgical interventions (p = 0.469). Conclusion: We demonstrated good overall clinical outcomes in LVAD patients undergoing NCS. With acceptable peri-operative mortality, NCS can be safely performed in LVAD patients on long-term support.

Surgical Challenges of Heart Mate 3 Pump Implantation in Aneurysmally Changed Heart Ventricles

We presented surgical treatment of three patients indicated for implantation of a permanent mechanical circulatory support device and with the associated left ventricular aneurysms. In order to evade the left ventricular rupture, adverse thromboembolic events and provide safe implantation of the inflow cannula, LVAD HM3 implantation together with the reconstruction of the left ventricular aneurysmal wall was performed in two patients. Regarding the third patient, LVAD implantation upon the reconstruction of the left ventricular wall was abandoned because there was no safe location for placement of the inflow cannula.

The Fallout of Heart Allocation System Changes: Practice Patterns and Landscape of the Recipient

The United Network for Organ Sharing (UNOS) implemented a new heart allocation system on October 1, 2018. This has inevitably changed the strategy to position the recipient to receive a donor organ. However, these changes in practice and the condition of the recipient has not been thoroughly evaluated. The UNOS database was evaluated from 2006 to 2019 for all adult heart transplant recipients. Patients were excluded if they were listed for multiple organs, re-transplantation, or for a diagnosis of congenital heart disease. This patient population was then analyzed for differences in pre-transplantation characteristics for January, 2006- September, 2018 (Era 1) versus October, 2018 - June, 2019 (Era 2). A total of 25,820 patients were identified with 25,209 and 619 patients in Era 1 and Era 2, respectively. Results from the comparison analysis are summarized in Table 1. Overall, patients spent fewer days on the waiting list in Era 2, but were more likely to have a temporary support device with extracorporeal membrane oxygenation or intra-aortic balloon pump. Additionally, distance traveled for donors was significantly farther in era 2. Consequently, patients were more likely to have a permanent mechanical circulatory support device implanted prior to the policy changes. The new status classification for recipients has resulted in more patients receiving transplant on ECMO and IABP compared to long-term durable devices. In addition, patients have a significantly shorter waiting time and distance travelled for donors is significantly increased. Major changes are observed in both practice patterns and recipient condition after the allocation changes, and more data are required to correlate this to outcomes and other differences.

Red blood cell mechanical fragility as potential metric for assessing blood damage caused by implantable durable ventricular assist devices: Comparison of two types of centrifugal flow left ventricular assist devices

Implantable Ventricular Assist Devices (VADs) have become a treatment of choice for patients with end-stage heart failure or cardiogenic shock, significantly increasing both survival rates and the quality of life of patients. Moreover, VAD use is growing as destination therapy for patients who require permanent mechanical cardiac circulatory support. This heightens the need to ensure VAD reliability and safety, even amidst challenges in optimization of pump design for minimal blood damage. Advanced design LVADs like the HVAD (Medtronic, Inc., Minneapolis, MN) and the Heartmate 3 (HM3; Abbott Labs, Chicago, IL) are centrifugal systems that had been favorably compared to the continuous flow axial pumps, such as the HeartMate II (HMII; Abbott Labs, Chicago, IL). While the HVAD and HMII are increasingly utilized in older pediatric populations in addition to the Berlin Heart Excor (Berlin Heart GmbH, Berlin Germany), implementation of VAD support for pediatric patients still lags behind adults. Recently, the HM3 has demonstrated superior performance to the HMII with respect to pump thrombosis in clinical trials and may also find utility in pediatric applications, particularly for adolescents. In this present work, performance of HVAD and HM3 were compared using basic laboratory tests and Red Blood Cell (RBC) Mechanical Fragility (MF), an assay that provides assessment of sub-hemolytic RBC damage which can be caused by VAD operation. RBC MF was assessed using electromagnetically driven bead milling with cylindrical beads in multiple different regimes for different sample stressing configurations. Induced hemolysis in the sample was measured non-invasively at different (increasing) cumulative stress duration intervals, to obtain a MF profile for each stressing regime. In a cohort of 13 HVAD and 7 HM3 patients, blood samples were obtained before surgery and at 1 h, 24 h, 1 week and 4 weeks after surgery. No significant differences were observed between the two VAD devices in conventional hemolysis markers including free hemoglobin, bilirubin, total LDH and haptoglobin, as well as in changes patient hemoglobin. HM3 demonstrated elevated, compared to HVAD, levels of LDH-1 at 24 h (p < 0.05) and 1 week (0.05 < p < 0.1) after surgery, with LDH-1 reverting to about pre-surgery levels at 4 weeks. These differences between pumps may have been attributed to confounders such as duration of cardiopulmonary bypass at time of LVAD implant. By one metric, RBC MF was similarly elevated for HM3 at both 24 h and 1 week after surgery, and also reverted to about pre-surgery levels at 4 weeks. Such changes in RBC MF results were observed for only one of the employed stressing regimes, highlighting the potential importance of matching the applied in vitro stress parameters to the particular nature of in vivo blood damage involved. Forthcoming work is planned for further analysis and reporting on additional aspects of this study.

The tightrope walk between temporary and permanent mechanical circulatory support.

In recent years, tremendous progress has been made in treatment and management of chronic heart failure, with novel drugs and devices contributing to reduced mortality and improved quality of life. In contrast, acute heart failure and cardiogenic shock have seen no such advancement in therapy and lack large positive outcome trials (1,2). Concomitantly, there is a strong rise in the use of temporary mechanical circulatory support (MCS) for cardiogenic shock (3,4), and some centers also implant permanent left ventricular assist devices (LVAD) at INTERMACS stages 1 to 3 (5). Yet, evidence from randomized controlled trials for temporary or permanent MCS remains limited, not at least because controlled MCS studies in acute heart failure and cardiogenic shock are admittedly difficult to conduct and to interpret. Therefore, MCS decision making in acute cardiac conditions is still largely based on experience and sometimes empiricism, and bridging and weaning strategies vary between centers. In this context, we read with great interest the report of Osswald and colleagues (6).

Minimally invasive embolectomy of HeartWare left ventricular assist device outflow graft.

Nowadays permanent mechanical circulatory support is a common treatment option for end-stage heart failure. Due to a shortage of donor heart transplantation not always being available for the patient in need to get life-saving treatment, a left ventricular assist devices (LVAD) is a suitable treatment option to overcome long waiting times on the transplant waiting list (1). Despite the technical evolution and better understanding of LVAD, there are still drawbacks in treating patients with an LVAD. Typical complications are bleeding complications, infections, right heart failure, and the risk of thrombus formation, which can lead to a device failure with a hemodynamic instability of the patient (2).

How Do Mechanical Circulatory Support Patients Die? Autopsy Findings for Bridge to Transplant LVAD/TAH Patients Who Do Not Survive to Transplant

Purpose Despite being life saving for end-stage heart failure patients, permanent mechanical circulatory support (MCS) is often the proximate cause of death in those that do not make it to transplant. Autopsy is the gold standard for causes of mortality, and is a vital tool for better understanding of pathology in this patient cohort. The aim of this study was to determine the frequency and outcomes of autopsy investigations over the course of a MCS program in a single center. Methods The autopsy findings of all patients who had a left ventricular assist device (LVAD) and total artificial heart (TAH) inserted between June 1994 and December 2016 as a bridge to transplant but subsequently died on pump were reviewed. Results A total of 187 patients had an LVAD or TAH implanted during the study. The cohort who died on pump (n=59; M=45, F=14) had an average age at implant of 53 ± 14 yrs, average INTERMACS score of 2, and average time on pump of 325 ± 316 days. Autopsies were conducted in 24/59 (41%) of patients. At autopsy, 8 patients had infection sited as cause of/contributing to the cause of death, one with purulent material obstructing the function of the pump. Six had explant swabs available. These were positive for MRSA, candida glabrata, pseudomonas fluorescens, scedosporium in 4 patients respectively, and 3/6 had positive explant swabs for pseudomonas aeruginosa. Lung injury was common, with 4 patients having acute respiratory distress syndrome, and 5 patients with diffuse alveolar damage. Four patients had intracranial hemorrhage, 2 patients had other bleeding (small bowel, haemopericardium), 1 patient had pump thrombus, 1 active myocarditis, and there was 1 accidental disconnection of the driveline. Conclusion Over an observational period of 22 years, the frequency of autopsies ordered was low. In order to keep patients alive to transplant, clinicians require a better understanding of causes of death. Patients with mechanical circulatory support have complex physiology and are at high risk of infection and bleeding complications.

Blood Stream Infection in Patients with Permanent Mechanical Circulatory Support: Risk Factors for On-Pump Mortality

Purpose Despite our improving knowledge, with the expanding use of mechanical circulatory support for end stage heart failure device related infection is increasingly prevalent. This study aims to better characterize the impact of multiple infections over a 22 year period. Methods This is a single center retrospective study of patients with mechanical circulatory support implanted from June 1994 to December 2016. Patients were studied for the incidence of blood stream infection (BSI), and ratio BSI:number of support days. The relationship between drive line infection/colonisation and BSI was reviewed. LVAD infection and its relationship to on pump mortality, and the relationship between multiple infections and mortality was analysed. Results A total of 191 patients (males=154, females n= 37), with an average age at implant of 51.4 years (±13.8) were studied. Patients had an average INTERMACS score of 1.83 (±0.61) and the main indication was bridge to transplant. Implanted devices included 166 LVADs, 14 biventricular assist device BiVADs, 7 total artificial hearts (TAH) and, 2 C-Pulse cuff devices. Average pump implant duration was 391 days (±338), median 312 days. There were 86/191 (45%) patients with one or more BSIs. The major responsible organisms for initial BSI were staphylococcus (64%), streptococcus (9.3%), enterococcus (7%), pseudomonas (4.7%), candida (4.2%) and E coli (3.5%). There were 0.53 events per patient year (EPPY). Of these, 66 (35% of total patients, 78% of BSI episodes) were a single episode, while 17 had multiple episodes (occurring at least 7 days after index infection) and 20 were polymicrobial, (2 organisms during time on pump). Candidaemia resulted in the highest relative mortality, with 63% infected dying on pump. 61/191 (32%) had driveline infection/colonisation. There was no difference in on-pump mortality for those with a single infection compared to those without, however there was a significant difference for those with multiple infection episodes (p Conclusion The study period for this research was the entire MCS program at our centre. This has allowed for a deeper understanding into the poor prognosis of patients with greater than one BSI during their time on pump.

Trends, Predictors, and Outcomes of Temporary Mechanical Circulatory Support for Postcardiac Surgery Cardiogenic Shock

Postcardiac surgery cardiogenic shock (PCCS) is seen in 2% to 6% of patients who undergo cardiac surgery. There are limited large-scale data on the use of mechanical circulatory support (MCS) in these patients. This study sought to evaluate the in-hospital mortality, trends, and resource utilization for PCCS admissions with and without MCS. A retrospective cohort of PCCS between 2005 and 2014 with and without the use of temporary MCS was identified from the National Inpatient Sample. Admissions for permanent MCS and heart transplant were excluded. Propensity-matching for baseline characteristics was performed. The primary outcome was in-hospital mortality and secondary outcomes included trends in use, hospital costs and lengths of stay. In the period between 2005 and 2014, there were 132,485 admissions with PCCS, with 51.3% requiring MCS. The intra-aortic balloon pump was the predominant device used with a steady increase in other devices. MCS use for more frequent in younger patients, males and those with higher co-morbidity. There was a decrease in MCS use across all demographic categories and hospital characteristics over time. Older age, female sex, previous cardiovascular morbidity and MCS use were independently predictive of higher in-hospital mortality. In 6,830 propensity-matched pairs, PCCS admissions that required MCS use, had higher in-hospital mortality (odds ratio 2.4; p<0.001), higher hospital costs ($98,759 ± 907 vs $81,099 ± 698; p<0.001) but not a longer length of stay compared with those without MCS use. In conclusion, in patients with PCCS, this study noted a steady decrease in MCS use. Use of MCS identified PCCS patients at higher risk for in-hospital mortality and greater resource utilization.

Age Is No Boundary to Long Term Survival on Permanent MCS: A Multicentre Experience

Purpose Advanced age of patients (pts) is often considered to be a risk for morbidity and mortality in permanent Mechanical Circulatory Support (MCS). We investigated outcomes of aged vs younger pts implanted with Jarvik 2000 (intraventricular-axial-flow pump with novel power delivery system) and enrolled in the Italian Registry (IR) in terms of length of MCS out of hospital. Outcomes were also analyzed according to preoperative conditions and INTERMACS scale. Methods and Materials From June 2006 to September 2012, 79 consecutive end-stage heart failure adult pts (70 males, mean age 62 ±8 yrs, median 64 yrs, 52% ischemic cardiomyopathy, 95% ineligible for heart transplantation) were enrolled in the Jarvik 2000 IR. 36 pts were ≥65yr old (mean age 69 ±3 yrs, median 69 yrs, group A), 43 patients were 1 yr) and early deaths (subgroup A2, B2, on MCS Results 17/36 pts (subgroup A1) and 14/43 pts (subgroup B1) were on MCS > 1 year, all of them being discharged home. No significant difference in gender, etiology, pre-operative hemodynamics, pre-implant INTERMACS mean class (3.6 and 3.5 respectively) or mean time on MCS (699±241 and 865±311 days respectively) were found between the 2 groups. In 9 and 10 pts respectively MCS is ongoing. 5/36 pts (subgroup A2) and 9/43 pts (subgroup B2) were on MCS Conclusions In our experience, elderly patients on permanent MCS have comparable outcomes to their younger counterparts. For both groups we confirmed that results are optimal when elective LVAD implantation is performed before development of inotropic dependency or cardiogenic shock. These results suggest that age need not be a limiting factor in the decision to implant MCS in end stage heart failure.

Preoperative INTERMACS Scale and Outcomes of “All-Comers” Undergoing LVAD Implantation: Results from the Jarvik 2000 Italian Registry

Purpose: INTERMACS scale is considered a valid score system to stratify patients' risk profile in terms of morbidity and mortality after mechanical circulatory support (MCS). This might be a particularly useful tool in destination therapy advanced age patients. We investigated outcomes of patients implanted with Jarvik 2000 (intraventricular-axial- flow pump with novel power delivery system) and enrolled in the Italian Registry. Outcomes were analized according to preoperative conditions, as per INTERMACS scale. Methods and Materials: From June 2006 to September 2011, 65 consecutive end-stage heart failure adult patients (58 males, mean BSA 1.90 m2, 53% ischemic cardiomyopathy) were enrolled in the Jarvik 2000 Italian Registry. Mean age was 63 ± 8 yrs (median 65 yrs), 95% were uneligible to heart transplantation. Relevant pre-operative data and outcomes were analyzed. In particular, two groups of patients were identified: long term survivors (group A, on device >1 yr, N=23) and early deaths (group B, on device < 1 month, N=12). Results: Overall mean time of patients on LVAD was 320 days and mean time of patients discharged out of hospital (72%) was 445 days. Overall survival was mainly impacted by peri-operative mortality. 12 patients died in early post-operative time (< 30 days) due to right ventricular failure (5), sepsis (3), bleeding (3) and HIT (Heparin Induced Throbocytopenia) (1). Late deaths were due to hemorrhagic stroke (5), non device related sepsis (5). No pump failure occurred in the whole series of patients. No significant difference in mean age, gender, etiology, pre-operative hemodynamics were found between the 2 groups. Pre-implant INTERMACS mean class was 3.5 in group A and 2.3 in group B (p=0.005). In group B, 5 patients had temporary MCS and 3 had CVVH before VAD implantation. Overall, probability of survival excluding early deaths, was 89%, 70%, 61% at 180 days, 1 and 2 years respectively. Conclusions: In our experience, preoperative higher INTERMACS class was correlated with higher survival. These results reinforce the importance of elective LVAD implantation before development of inotropic dependency or cardiogenic shock in permanent MCS patients.

Permanent mechanical circulatory support in non-transplant candidates

Objectives: Facing the rapidly increasing population of older patients with end-stage heart failure, permanent mechanical circulatory support (MCS) has gained increasing importance. We analyzed the courses of 141 non-transplant candidates who were supported by 12 different mechanical circulatory support (MCS) devices.

Outcomes of elective versus emergent permanent mechanical circulatory support in the elderly: A single-center experience

Advanced age is considered a relative contraindication to heart transplantation, but there is no published consensus on critical age in the case of mechanical circulatory support (MCS). This single-center study investigated outcomes of elective versus emergent implementation of permanent MCS in the elderly. Between January 1, 2006 and April 1, 2009, 31 patients, >65 years of age, were supported with a ventricular assist device (VAD), intended for permanent support, at our institution. The 28 left VAD (LVAD) recipients were divided into two groups: a survival group, n = 13 (ongoing MCS at 180 days or weaned); and a non-survival group, n = 15 (death on device within 180 days). In addition, the survival rate of LVAD recipients according to pre-operative INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support) status was analyzed. The cumulative survival rates for the LVAD patients were 75% at 30 days, 46% at 180 days and 39% at 1 year after VAD implantation. The cumulative survival rates at 30 days, 180 days and 1 year were 71%, 47% and 35% for INTERMACS Level I to III (n = 17) patients vs 81%, 45% and 45% for INTERMACS Level IV to V (n = 11) patients (p = 0.9), respectively. Median age of LVAD recipients was 69 (range 66 to 80) years; 4 were women. Median support time was 565 (range 228 to 1,257) days. In 9 recipients support is ongoing. Both complications profiles and causes of death are reported. Our experience indicates that permanent MCS may be successful in highly selected elderly patients with terminal heart failure, especially when elective implantation is performed before development of inotropic dependency or cardiogenic shock. However, outcomes at 12 months in this selective elderly population remain uniformly poor.

Destination Therapy: Current Results and Future Promise

The landmark Randomized Evaluation of Mechanical Assistance in the Treatment of Congestive Heart Failure (REMATCH) trial demonstrated that the implantation of left ventricular assist devices (LVADs) as an alternative to heart transplantation, or destination therapy (DT) is superior to any known medical therapy in patients with end-stage heart failure who are not eligible for transplantation. In this article, we review results of the first United States and European clinical trials of DT, including the REMATCH, the Investigation of the Non-Transplant Eligible Patients who are Inotrope Dependent (INTREPID), and the Clinical Utility Baseline Study (CUBS) trials, as well as the outcomes of the first DT implantations in the post-REMATCH era in the United States. The article summarizes the current state of knowledge and future directions in the field of permanent mechanical circulatory support therapy as an alternative to heart transplantation.

Mechanical Reliability of the Jarvik 2000 Heart

Device failure is a limitation of permanent mechanical circulatory support. We studied the mechanical reliability of the Jarvik 2000 Heart, an axial flow pump with ceramic bearings designed to provide more than 10 years' durability. The Jarvik 2000 Heart was implanted in 102 patients between April 2000 and December 2004. Eighty-three pumps with an abdominal driveline were implanted as a bridge-to-transplantation, and 19 with postauricular power supply as lifetime therapy. Eighteen pumps were recovered intact after clinical use and run continuously on the bench to further assess durability. No implantable component failure occurred either in patients or during bench testing. The cumulative pump run-time was 110 years: 59 years overall in vivo and 51 years in vitro. The mean support time for bridge-to-transplant recipients was 159 days, and for discharged lifetime-therapy recipients 551 days. Six recipients were supported moer than 2 years, with the longest ongoing approaching 5 years. External cables caused three system failures, with a 95% freedom from system failure at 4 years. Device malfunctions, related to external cables (9) and lack of a backup battery (1), caused no adverse consequences. Before introduction of noncorrosive, gold-plated stainless steel connectors, corrosion was observed on three connectors to the retroauricular power supply. The Jarvik 2000 Heart has had no implantable component failure. Meaningful durability data and failure mode can only be established by real-time testing in patients. The reliability and dependability of this device, in addition to the exchangeability of external components, give promise for long-term circulatory support in critically ill heart failure patients.

Mechanical circulatory support: state of the art and future perspectives.

Mechanical circulatory support (MCS) has been viewed, until recently, as a rescue therapy to be applied when all else fails. Not surprisingly, this has resulted in suboptimal outcomes. Fortunately, the perseverance of a few dedicated groups has produced improved outcomes and the concept of MCS as an elective therapy is now steadily gaining acceptance. This is particularly true in the postcardiotomy setting, where a large number of new options are now available. The recently completed REMATCH study has demonstrated the feasibility and efficacy of permanent MCS as a therapy for end-stage heart failure, despite a high rate of device complications. Donor availability is decreasing and biological solutions will not be available for many years. New generation implantable rotary pumps, a fully implantable left ventricular assist device and a total artificial heart are all undergoing clinical evaluation, and several new exciting designs are in preclinical evaluation. A new paradigm for the treatment of terminal heart failure is emerging, where an unpredictable and expensive medically managed death in an intensive care unit setting is being exchanged for a more predictable high-cost, front-loaded therapy with management from the outpatient clinic. The perfusionist community has much to contribute to this emerging life support field, not only in the perioperative period, but also in providing ongoing technical support to hospital staff, recipients and their families.