Results of a multicenter clinical trial with the Thoratec Implantable Ventricular Assist Device⁎⁎Thoratec Corporation, Pleasanton, Calif

Less Invasive Left Ventricular Assist Device Implantation Is Safe and Feasible in Patients With Smaller Body Surface Area

OBJECTIVE

Smaller body surface area (BSA) frequently precludes patients from left ventricular assist device (LVAD) therapy. We sought to investigate the clinical outcomes in patients with small BSA undergoing less invasive LVAD implantation.

METHODS

We conducted a retrospective review of 216 patients implanted with HeartMate 3 LVAD (Abbott, Chicago, IL) via less invasive surgery at our institution. Patients were dichotomized based on their preimplant BSA for comparison between small BSA (≤1.8 m2) and normal/large BSA (>1.8 m2). We analyzed patient perioperative characteristics and outcomes.

RESULTS

In our study, small BSA was found in 32 patients (14.8%), while 184 patients (85.2%) had normal/large BSA. Women were more prevalent in the small BSA group (50.0% vs 13.0%, P < 0.001). Preoperative and intraoperative data showed comparable results. Major complications and hospital length of stay did not differ by BSA group. Patients with smaller BSA had significantly decreased pump parameters at discharge, including LVAD flow (4.11 ± 0.49 vs 4.60 ± 0.54 L/min, P < 0.001) and pump speed (5,200 vs 5,400 rpm, P < 0.001). Survival to discharge and within 6 months after implantation were similar between the groups.

CONCLUSIONS

Our study results suggest that less invasive HeartMate 3 implantation can be safely performed and demonstrates equivalent outcomes in patients with smaller body habitus. Randomized trials are required to confirm our data.

Hemostasis in Pediatric Extracorporeal Life Support: Overview and Challenges

Extracorporeal membrane oxygenation (ECMO) and ventricular assist devices (VADs) are increasingly used in critically ill children. Despite improvements in mechanical design and clinical management, thromboembolic and hemorrhagic events remain significant causes of morbidity and mortality related to the use of both devices. Choice of anticoagulant agents and assays for monitoring continue to present challenges in management. In this review, we describe the incidence and risk factors for thrombosis and hemorrhage, the different types of anticoagulants currently in use, the assays available for monitoring anticoagulation, and management of thromboembolic and bleeding complications in children on mechanical circulatory support (MCS). We conclude by emphasizing the areas that need further study to minimize the risk for thrombosis and hemorrhage in the use of ECMO and VAD in children.

Medium term results following heart transplantation for end stage heart failure: A single center experience of 257 patients

OBJECTIVE

End stage heart failure is a lethal disease with a dismal 5 year survival. Heart transplantation has proven to be a highly effective modality of treatment in appropriately selected group of such patients. This is a retrospective analysis of medium term outcomes of heart transplantation in the setting of a private health facility in India. The objective of this study was two fold.

METHODS

The outcome of 257 heart transplants done at a single centre from October 2012 to October 2019 was analyzed. Patients with combined Heart and lung transplants and those whose complete medical records were unavailable were excluded from the study. Survival was tracked at 60 days, 90 days, one year and beyond for a maximum of 7 years. Preoperative patient risk profiles were characterized on the basis of INTERMACS category.

RESULTS

There were 176 male and 81 female patients. The age range was from 8 months to 78 years with a mean of 32.9 years. Survival at 2 months was 87%, at 90 days was 83%, at one year was 81%, 2 years was 75%, at 3 years was 72% and at 5 years and beyond was 62% for the whole series. Strong predictors of 90 day mortality included INTERMACS category (odd's ratio 0.289, p = 0.000) and creatinine more than 1.5 mg/dl (odd's ratio 2.48, p = 0.056). Recipient pulmonary vascular resistance and donor organ ischemic times were not found to be statistically significant factors affecting outcome. Medium term survival was influenced by INTERMACS category (Hazard ratio > 3 for INTERMACS category 1 compared to INTERMACS 4 or 5, p < 0.0001) and creatinine > 1.5 mg/dl (Hazard ratio 2.15, p = 0.003). This effect of creatinine was related to the age of the recipient. Hazard ratio 1.4, p = 0.524 if age <30 and Hazard ratio 4.78, p = 0.006, if age was >50.

CONCLUSION

Satisfactory medium term outcome is possible after heart transplantation even in resource constrained environment of a developing country.

Review and reflections about pulsatile ventricular assist devices from history to future: concerning safety and low haemolysis-still needed

Since the first use of a ventricular assist device in 1963 many extracorporeal and implantable pulsatile blood pumps have been developed. After the invention of continuous flow blood pumps the implantable pulsatile pumps are not available anymore. The new rotary pumps spend a better quality of life because many of the patients can go home. Nevertheless, the extracorporeal pulsatile pumps have some advantages. They are low-cost systems, produce less haemolysis and heart-recovery can be tested easily. Pump failure is easy to realize because the pumps can be observed visually. Pump exchange can be done easily without any chirurgic surgery. As volume displacement pumps they can produce high blood pressure, so they are the only ones suitable for pediatric patients. Therefore, they are indispensable for clinical use today and in the future. In this work, nearly all pulsatile blood pumps used in clinical life are described.

2019 EACTS Expert Consensus on long-term mechanical circulatory support

Long-term mechanical circulatory support (LT-MCS) is an important treatment modality for patients with severe heart failure. Different devices are available, and many-sometimes contradictory-observations regarding patient selection, surgical techniques, perioperative management and follow-up have been published. With the growing expertise in this field, the European Association for Cardio-Thoracic Surgery (EACTS) recognized a need for a structured multidisciplinary consensus about the approach to patients with LT-MCS. However, the evidence published so far is insufficient to allow for generation of meaningful guidelines complying with EACTS requirements. Instead, the EACTS presents an expert opinion in the LT-MCS field. This expert opinion addresses patient evaluation and preoperative optimization as well as management of cardiac and non-cardiac comorbidities. Further, extensive operative implantation techniques are summarized and evaluated by leading experts, depending on both patient characteristics and device selection. The faculty recognized that postoperative management is multidisciplinary and includes aspects of intensive care unit stay, rehabilitation, ambulatory care, myocardial recovery and end-of-life care and mirrored this fact in this paper. Additionally, the opinions of experts on diagnosis and management of adverse events including bleeding, cerebrovascular accidents and device malfunction are presented. In this expert consensus, the evidence for the complete management from patient selection to end-of-life care is carefully reviewed with the aim of guiding clinicians in optimizing management of patients considered for or supported by an LT-MCS device.

Non-Pulsatile Axial flow Ventricular Assist Device for Right Systemic Ventricle failure Late after Senning Procedure

Cardiac transplantation is an ever more frequent requirement for patients presenting with end-stage right systemic ventricular failure late after atrial switch operations. But as the time on the donor waiting list lengthens, the clinical conditions of these patients can easily and abruptly deteriorate, sometimes requiring systemic ventricular assistance. We document the first case of right systemic ventricular assistance with a De Bakey VAD axial pump in a patient presenting with systemic ventricular failure 23 years after procedure. He rapidly recovered total autonomy and was thus able to participate in a rehabilitation program to optimize his condition for heart transplantation.

Contemporary Management of Cardiogenic Shock: A Scientific Statement From the American Heart Association

Cardiogenic shock is a high-acuity, potentially complex, and hemodynamically diverse state of end-organ hypoperfusion that is frequently associated with multisystem organ failure. Despite improving survival in recent years, patient morbidity and mortality remain high, and there are few evidence-based therapeutic interventions known to clearly improve patient outcomes. This scientific statement on cardiogenic shock summarizes the epidemiology, pathophysiology, causes, and outcomes of cardiogenic shock; reviews contemporary best medical, surgical, mechanical circulatory support, and palliative care practices; advocates for the development of regionalized systems of care; and outlines future research priorities.

Limited Utility of Tricuspid Valve Repair at the Time of Left Ventricular Assist Device Implantation

BACKGROUND

The optimal management of tricuspid regurgitation (TR) in patients undergoing left ventricular assist device (LVAD) implantation is controversial. This study was undertaken to determine the impact of tricuspid valve repair (TVR) at the time of LVAD implantation on survival.

METHODS

The Interagency Registry for Mechanically Assisted Circulatory Support was used to analyze the outcomes of patients undergoing LVAD implantation as destination therapy with or without concomitant TVR.

RESULTS

Among 2,527 patients undergoing implant of a continuous flow LVAD as destination therapy during the study period, 989 (39%) had moderate or severe TR. The management of TR was not uniform among these patients. Patients with moderate and severe TR underwent TVR in 16.7% and 35.3% of cases, respectively. Moderate and severe TR at the time of LVAD implantation were associated with poorer survival over the entire follow-up period (p = 0.009). Interestingly, TVR at the time of LVAD implantation did not confer improved survival, even among patients with preimplant moderate or severe TR. A potential explanation for this finding is that patients with preimplant moderate or severe TR who underwent LVAD implant with concomitant TVR commonly experienced recurrent, late TR (21% to 27%).

CONCLUSIONS

Tricuspid valve repair is performed commonly at the time of LVAD implant despite the fact that it does not confer a clear survival benefit. For many patients, LVAD implant alone relieves preimplant TR as effectively as LVAD implant with TVR. Further study is necessary to determine what factors lead to recurrence of late TR in LVAD patients both with and without TVR.

Outcomes of biventricular mechanical support patients discharged to home to await heart transplantation

BACKGROUND

The use of left ventricular assist devices has grown rapidly in recent years for patients with end-stage heart failure. A significant proportion of patients require both left- and right-sided support with biventricular assist devices (BiVADs) as a bridge to transplantation. Traditionally, these patients have waited in the hospital until they receive a transplant.

PURPOSE

The aim of this study was to characterize the clinical course of BiVAD patients discharged to home to await heart transplantation.

METHODS

Between November 2009 and July 2011, 24 adult patients underwent Thoratec paracorporeal BiVAD placement at the University of California Los Angeles, all with an Interagency Registry for Mechanically Assisted Circulatory Support score 1 or 2. The disposition, complications, and rehospitalizations of these subjects were retrospectively reviewed.

RESULTS

Fourteen of the 24 patients were successfully discharged to home, with a mean time of 60 ± 27 days from BiVAD implantation to discharge. Ninety-three percent (13/14) of the patients sent home went on to be transplanted. Eleven of the 14 (79%) came in from home to receive their transplant. The mean time from BiVAD implantation to transplantation was 100 ± 65 days. Of the 14 patients discharged to home, there were 18 readmissions in 8 patients.

CONCLUSION

In this small single-center review, we found that complex medical patients with BiVADs can be discharged to home and can await a heart transplant from home under the close management of multidisciplinary acute care and outpatient teams.

Review of recent results using computational fluid dynamics simulations in patients receiving mechanical assist devices for end-stage heart failure

Many end-stage heart failure patients are not eligible to undergo heart transplantation due to organ shortage, and even those under consideration for transplantation might suffer long waiting periods. A better understanding of the hemodynamic impact of left ventricular assist devices (LVAD) on the cardiovascular system is therefore of great interest. Computational fluid dynamics (CFD) simulations give the opportunity to study the hemodynamics in this patient population using clinical imaging data such as computed tomographic angiography. This article reviews a recent study series involving patients with pulsatile and constant-flow LVAD devices in which CFD simulations were used to qualitatively and quantitatively assess blood flow dynamics in the thoracic aorta, demonstrating its potential to enhance the information available from medical imaging.

Pediatric mechanical circulatory support

Mechanical circulatory support (MCS) in the pediatric heart failure population has a limited history especially for infants, and neonates. It has been increasingly recognized that there is a rapidly expanding population of children diagnosed and living with heart failure. This expanding population has resulted in increasing numbers of children with medically resistant end-stage heart failure. The traditional therapy for these children has been heart transplantation. However, children with heart failure unlike adults do not have symptoms until they present with end-stage heart failure and therefore, cannot safely wait for transplantation. Many of these children were bridged to heart transplantation utilizing extracorporeal membranous oxygenation as a bridge to transplant which has yielded poor results. As such, industry, clinicians, and the government have refocused interest in developing increasing numbers of MCS options for children living with heart failure as a bridge to transplantation and as a chronic therapy. In this review, we discuss MCS options for short and long-term support that are currently available for infants and children with end-stage heart failure.

Ethical dilemmas surrounding the use of ventricular assist devices in supporting patients with end-stage organ dysfunction

Successful practice of cardiovascular medicine requires familiarity with the complex ethical issues that accompany therapeutic innovation and diffusion. Even as technologies transition from experimental to standard care, challenges remain. Mechanical circulatory support devices, for instance, are increasingly conceptualized as conventional therapies. Despite this, or perhaps because of it, the ethical issues surrounding the use of these devices in patients with end-stage organ dysfunction are becoming increasingly apparent. In this paper, we provide an introduction to ethical considerations related to the use of ventricular assist devices (VADs) in end-stage organ failure, focusing on three stages or decision points: initiation, continued use, and deactivation. Our goal is not to exhaustively resolve these dilemmas but to illustrate how ethical considerations relate to decision making.

Ventricular assist devices: initial orientation

Ventricular assist device (VAD) technology has come from large pulsatile-flow devices with a high rate of technical malfunctions to small continuous flow (cf) devices. Mechanical circulatory support (MCS) systems may be used as short-, mid- or long-term support. Especially if mid- or long-term support is anticipated left VADs (LVADs) have been reported with excellent one and two year survival rates and improved quality of life (QoL). Timing of implantation, patient selection, assessing function of the right ventricular and surgical considerations regarding surgical access side, valve pathology and exit side of the percutaneous lead remain crucial issues for the outcome. In contrast VADs designed for children especially for all age groups, are still underrepresented but increased experience with existing pediatric VADs as well as introduction of second and third generation VADs into in the pediatric age group, offer new perspectives.

Morphologic changes in the aortic wall media after support with a continuous-flow left ventricular assist device

BACKGROUND

Continuous-flow left ventricular assist devices (LVADs) provide durable, reliable, energy-efficient long-term support. However, the biologic effects of continuous flow are not completely known. Therefore, we examined aortic wall morphology in patients with heart failure before and after prolonged circulatory support with a continuous-flow LVAD.

METHODS

After applying a partial aortic occlusion vascular clamp in the lower half of the ascending aorta, we removed samples of aortic wall tissue and then attached the outflow graft of the pump. Samples were obtained from 11 patients (9 men and 2 women, mean age 65 ± 7 years) with severe heart failure at the time of LVAD implantation. We obtained matched specimens at explantation after heart transplantation (n = 5) or autopsy (n = 6). These specimens were removed from the distal ascending aorta, remote from the aortic anastomotic site. Tissue sections were stained with hematoxylin and eosin, Movat's pentachrome and Masson's trichrome. Smooth muscle actin immunohistochemistry was performed on all sections. To evaluate the morphology of the aortic wall media, we quantitatively graded tissue sections for medial thickness, medial degenerative changes, smooth muscle cell (SMC) disorientation and depletion, elastic fiber fragmentation and depletion, medial fibrosis and atherosclerotic changes.

RESULTS

The mean duration of support was 140 ± 136 days (range 87 to 580 days). The histologic evaluation and comparison of specimens obtained before and after LVAD support showed significantly increased foci of medial degeneration, SMC depletion, elastic fiber fragmentation, medial fibrosis and atherosclerotic changes after LVAD support. Mean medial thickness was not significantly different after LVAD support. We observed similar changes between samples obtained at transplantation and those obtained at autopsy.

CONCLUSIONS

After continuous-flow LVAD support, the morphology of the aortic wall media was altered in all of our patients. The clinical relevance of these findings is unknown.

Trends in long-term mechanical circulatory support for advanced heart failure in the UK

AIMS

Heart transplantation (HTx) is limited by the scarcity of suitable donor hearts. Consequently, more patients with advanced heart failure require a ventricular assist device (VAD). We report U.K. activity, trends, and outcome for long-term VAD support as a bridging therapy to HTx.

METHODS AND RESULTS

Patients were grouped into three eras: E1, February 2004-March 2006; E2, April 2006-March 2009; and E3, April 2009-March 2011. Exclusions were patients who received isolated short-term support or extracorporeal membrane oxygenation without prior or subsequent long-term VAD support. A total of 247 patients received VAD support; 202 left ventricular (LVAD) support alone and 45 both left and right ventricular support. Activity increased over time, from 36 patients implanted in E1 to 123 in E3. Overall, 46 patients received a first-generation device, 80 a second-generation device, and 121 a third-generation device. Use of third-generation devices increased from <6% in E1 to 78% in E3. Median duration of LVAD support increased from 141 days in E1 to 578 days in E3 (P < 0.001). Overall survival to 1 year after LVAD implant rose from 58.3% [95% confidence interval (CI) 40.7-72.4%] in E1 to 72.5% (95% CI 63.3-79.8%) in E3 (P = 0.21), and improved significantly with device generation; at 1 year, 50% of patients with first-generation devices were alive compared with 68.1% and 76.9% of patients with second- and third-generation devices, respectively (P = 0.002). These differences remained after risk adjustment. HTx following LVAD implant reduced over time (P < 0.001).

CONCLUSION

VAD activity and duration of support have increased. There has been a shift from first- and second- to third-generation devices, and an associated improvement in survival.

Cardiogenic Shock and the ICU Patient

Cardiogenic shock is one of the most important complications of acute myocardial infarction (MI) and acute left ventricular failure (LVF). It threatens the life of 5–10% of patients with ST-segment elevation myocardial infarction (STEMI) particularly in the presence of inappropriately low peripheral vascular resistance. Cardiogenic shock results in poor tissue perfusion, end-organ damage and carries a high mortality risk. The goal of therapy is to prevent end-organ dysfunction and severe metabolic derangement by raising mean arterial blood pressure, which is achieved with the use of inotropes and vasopressors, often at the expense of tachycardia, elevated myocardial oxygen consumption and extended myocardial ischaemia. Current therapeutic approaches include early coronary artery revascularisation (which has significantly improved the survival rate), fluid resuscitation, inotropic support and mechanical circulatory support using intra-aortic balloon pumps or ventricular assist devices. In this article, we review the pathophysiology, diagnosis and management of cardiogenic shock.

Heart failure and mechanical circulatory assist devices

During the last 20 years, the management of heart failure has significantly improved by means of new pharmacotherapies, more timely invasive treatments and device assisted therapies. Indeed, advances in mechanical support, namely with the development of more efficient left ventricular assist devices (LVAD), and the total artificial heart have reduced mortality and morbidity in patients with end-stage heart failure awaiting for transplantation. However, the transplant cannot be the only solution, due to an insufficient number of available donors, but also because of the high number of patients who are not candidates for severe comorbidities or advanced age. New perspectives are emerging in which the VAD is no longer conceived only as a “Bridge to Transplant”, but is now seen as a destination therapy. In this review, the main VAD classification, current basic indications, functioning modalities, main limitations of surgical VAD and the total artificial heart development are described.

Past and present of cardiocirculatory assist devices: a comprehensive critical review

During the last 20 years, the management of heart failure has significantly improved by means of new pharmacotherapies, more timely invasive treatments and device assisted therapies. Indeed, advances in mechanical support, namely with the development of more efficient left ventricular assist devices (LVADs), and the total artificial heart have reduced mortality and morbidity in patients awaiting transplantation, so much so, that LVADs are now approved of as a strategy for destination therapy. In this review, the authors describe in detail the current basic indications, functioning modalities, main limitations of surgical LAVDs, total artificial heart development, and percutaneous assist devices, trying to clarify this complex, but fascinating topic.

Patient selection for ventricular assist devices: a moving target

The number of patients with advanced heart failure that has become unresponsive to conventional medical therapy is increasing rapidly. One of the most promising new alternatives to heart transplantation is use of ventricular assist devices (VADs). To date, there are no guidelines for appropriate selection for use of these devices that are approved by national societies in the field. This review addresses all of the general criteria for clinicians to keep in mind regarding when to refer a patient for evaluation and the specific issues addressed in patient selection. The field of mechanical circulatory support has advanced significantly over the past 10 years, resulting in rapid expansion of patients with advanced heart failure who can benefit from implantable devices. With progress of technology, limitations associated with age, body size, and comorbidities gradually become less prohibitive. The continuing simplification of design along with continued reduction in size of the devices, plus eventual elimination of the external drive line will make the use of VADs a superior option to heart transplant and even to medical management in many patients. We anticipate that the patient selection process outlined in the present review will continue to shift toward less advanced cases of heart failure.

Gender differences during mechanical circulatory support

Long-term mechanical circulatory support (MCS) with ventricular assist devices (VADs) is now an acceptable option for patients with end-stage heart failure (HF). There are growing numbers of reports identifying sex-related differences in the development and prognosis of HF and cardiac surgery. With the experience of 1,607 VAD implantations in our institution we are the first to analyze our data to determine gender distribution in our patient populations and the effect of gender on outcomes. Of the total 1,456 patients with MCS, 1,225 were male and 231 female. The patients were divided into three age groups-below 13 years (group 1, n = 100), between 13 and 50 years (group 2, n = 540) and older than 50 years (group 3, n = 824). Five-year survival, HF etiology, and procedural success, defined as 30-day and 5-year survival were analyzed retrospectively. In group 1 the gender distribution was equal; the leading HF etiology was dilated cardiomyopathy (DCMP) with 17% in male (n = 17) and 19% in female (n = 19) patients, followed by congenital diseases (13% in male versus 9% in female) and postcardiotomy failure (13% in male versus 8% in female). No differences were seen in 5-year survival and procedural success. In group 2, significantly more men (n = 451, p < 0.0001) were supported by VADs. DCMP was the major cause for VAD implantation (54%) and was significantly more frequent in men (57.6%, p = <0.0001). Male patients were older (mean age = 37.1 years, p < 0.0001), with a longer median support time (151.6 days, p < 0.0001) and a higher median weight (78.2 kg, p < 0.0001). No difference was seen in procedural success whereas 5-year survival was better in men than in women (53% vs. 42%, p = 0.02).Group 3 consisted of 723 male patients and 101 female patients (p < 0.0001). Ischemic cardiomyopathy was the main HF etiology (37.9 %) and it was significantly more often the reason for left ventricular assist device support in men (p = 0.009). No differences were seen in procedural success; 5-year survival showed a better outcome in men (49% vs. 25%, p = 0.026). In patients supported by a VAD, gender has a significant impact on the distribution of diagnoses in the adult population. Women were underrepresented in the age group 13-50 years, and 50 years and older, and women had a higher risk for mortality on VAD support in the adult age groups (groups 2 and 3).

Prospective trial of a pediatric ventricular assist device

BACKGROUND

Options for mechanical circulatory support as a bridge to heart transplantation in children with severe heart failure are limited.

METHODS

We conducted a prospective, single-group trial of a ventricular assist device designed specifically for children as a bridge to heart transplantation. Patients 16 years of age or younger were divided into two cohorts according to body-surface area (cohort 1, <0.7 m(2); cohort 2, 0.7 to <1.5 m(2)), with 24 patients in each group. Survival in the two cohorts receiving mechanical support (with data censored at the time of transplantation or weaning from the device owing to recovery) was compared with survival in two propensity-score-matched historical control groups (one for each cohort) undergoing extracorporeal membrane oxygenation (ECMO).

RESULTS

For participants in cohort 1, the median survival time had not been reached at 174 days, whereas in the matched ECMO group, the median survival was 13 days (P<0.001 by the log-rank test). For participants in cohort 2 and the matched ECMO group, the median survival was 144 days and 10 days, respectively (P<0.001 by the log-rank test). Serious adverse events in cohort 1 and cohort 2 included major bleeding (in 42% and 50% of patients, respectively), infection (in 63% and 50%), and stroke (in 29% and 29%).

CONCLUSIONS

Our trial showed that survival rates were significantly higher with the ventricular assist device than with ECMO. Serious adverse events, including infection, stroke, and bleeding, occurred in a majority of study participants. (Funded by Berlin Heart and the Food and Drug Administration Office of Orphan Product Development; ClinicalTrials.gov number, NCT00583661.).

Miniaturization of mechanical circulatory support systems

Heart failure (HF) is increasing worldwide and represents a major burden in terms of health care resources and costs. Despite advances in medical care, prognosis with HF remains poor, especially in advanced stages. The large patient population with advanced HF and the limited number of donor organs stimulated the development of mechanical circulatory support (MCS) devices as a bridge to transplant and for destination therapy. However, MCS devices require a major operative intervention, cardiopulmonary bypass, and blood component exposure, which have been associated with significant adverse event rates, and long recovery periods. Miniaturization of MCS devices and the development of an efficient and reliable transcutaneous energy transfer system may provide the vehicle to overcome these limitations and usher in a new clinical paradigm in heart failure therapy by enabling less invasive beating heart surgical procedures for implantation, reduce cost, and improve patient outcomes and quality of life. Further, it is anticipated that future ventricular assist device technology will allow for a much wider application of the therapy in the treatment of heart failure including its use for myocardial recovery and as a platform for support for cell therapy in addition to permanent long-term support.

[Improvements in implantable mechanical circulatory support systems : literature overview and update]

In recent years, ventricular assist devices (VAD) supporting the left (LVAD), the right (RVAD) or both ventricles (BVAD) have rapidly emerged as the standard of care for advanced heart failure patients. Both the numbers and ages of patients in which they are used are rising worldwide, especially when used as a permanent support (bridge to destination, BTD). Due to the continuing lack of donor organs, these devices now represent a viable alternative to bridge patients to transplantation (BTT), with a 1-year survival rate of 86%. BTD, especially in long-term support, might be a valid, and the sole, option for those patients in whom heart transplantation is contraindicated. Patient selection, pre- and intra-operative preparation, as well as the timing of VAD implantation are important factors critical to successful circulatory support. While BTT remains the goal in the majority of patients, the number of permanent VADs (i. e. BTD) is rising significantly. Although explantation of a VAD system as a bridge to recovery (BTR) can be considered in only a small number of patients, it represents a very special part of this therapy modality.

Continuous-flow left ventricular assist device support in patients with advanced heart failure: points of interest for the daily management

Today, continuous-flow left ventricular assist devices (cf-LVADs) are implanted more often in patients with end-stage heart failure. Because of greater durability they can be implanted for an extended period of time. As a result of increased numbers of patients on cf-LVAD support, healthcare professionals should be aware of the potential complications inherent to this therapy. Both bleeding and thrombosis may occur, and also complications related either to the device itself or to the ensuing altered haemodynamics, valvular pathology, and rhythm disturbances such as ventricular tachycardias and fibrillation. Accurate clinical evaluation, together with an electrocardiogram and, if necessary, combined with an echocardiogram, is obligatory in these situations. This review summarizes common complications complemented by a few clinical cases.

Intraoperative transesophageal echocardiography and ventricular assist device insertion

A decade after cardiac surgery was established, transesophageal echocardiography (TEE) was developed and used to evaluate perioperative cardiac performance. It has become an invaluable tool to provide real-time information in the cardiac operating room. TEE provides practical and useful information prior to insertion as well as after placement of the device. Additionally, during episodes of device malfunction or hemodynamic instability, TEE can be extremely useful in defining the etiology of the problem. As ventricular assist devices (VADs) have undergone evolution in design and as more VADs are being implanted, the development of specific indications for TEE use during device placement is a relevant issue. Formal guidelines for use of TEE during VAD insertion are yet to be adopted or implemented, but for now TEE remains an essential tool for managing this patient population.

Survival after biventricular assist device implantation: an analysis of the Interagency Registry for Mechanically Assisted Circulatory Support database

BACKGROUND

Patients requiring biventricular assist device (BiVAD) for mechanical circulatory support (MCS) have substantially worse outcomes than patients requiring left VAD (LVAD) support only. Patient-specific risk factors have yet to be consistently identified in a large, multicenter registry, which may underlie the poorer outcomes for BiVAD patients. The Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) is a registry of U.S. Food and Drug Administration-approved durable MCS devices used for bridge-to-transplantation, destination therapy, or recovery. The purposes of this study were to 1) identify the underlying pre-implant characteristics of the population requiring BiVAD support that contribute to reduced survival, and 2) identify differences in postoperative outcomes with respect to adverse events compared with patients supported with LVAD alone.

METHODS

From June 2006 to September 2009, 1,646 patients were entered into the INTERMACS database in which adverse events and outcomes were recorded for primary implants with LVAD or BiVAD. Competing outcomes methodology was used to estimate the time-related probability of death, transplant, or recovery. Overall survival for all groups was analyzed with Kaplan-Meier methods and Cox proportional regression analysis.

RESULTS

The distribution of primary device implants included 1,440 LVADs and 206 BiVADs. BiVAD patients presented with a lower INTERMACS profile 93% in INTERMACS 1 or 2, compared with 73% for LVAD patients (p < 0.001). Survival at 6 months was 86% for LVADs and 56% for BiVADs (p < .0001). Adverse event rates, expressed as episodes/100 patient-months for the BiVAD group compared with LVAD, were significantly higher for infection (33.2 vs 14.3), bleeding (71.6 vs 15.5), neurologic events (7.9 vs 2.6), and for device failure (4.9 vs 2.0).

CONCLUSIONS

Patients requiring BiVAD support at the time of durable MCS implant are more critically ill at the time of MCS implant. BiVAD patients experience worse survival than patients supported with LVAD alone and higher rates of serious adverse events. Characteristics of the population present at the time of BiVAD implant likely influence post-implant MCS outcomes.

Current outcome of heart transplantation: a 10-year single centre perspective and review

BACKGROUND

Heart transplantation (HTx), the gold standard therapy for advanced heart failure, is limited by donor availability; alternative therapies are now becoming available.

AIM

We examined the outcome of HTx with current immunosuppressive and adjunctive therapy.

DESIGN AND METHODS

We analysed the outcome of 399 consecutive patients who underwent transplantation at our centre (1995-2007). Prior to HTx 23% (98) required inotropic support, 8.5% (34) an intra-aortic balloon pump and 11% (43) a ventricular assist device.

RESULTS

Actuarial patient survival was 86% at 30 days, 79% at 1 year and 62% at 10 years. Survival was similar regardless of the heart failure severity, P=0.22. The cumulative incidence of allograft vasculopathy, Costanzo grade≥2, was 7% at 5 years and 23% by 10 years with an 11% cumulative probability of requiring a percutaneous coronary intervention by 10 years. Allograft function was preserved with a mean±SD left ventricular ejection fraction of 73±7% at 1 year and 74±8% at 10 years. The cumulative incidence of malignancy by 10 years was 27% (skin malignancy 13% and post transplant lymphoproliferative diseases 10%). The cumulative incidence of developing chronic kidney disease (CKD) with an estimated glomerular filtration rate≤45 ml/min/1.73 m2 was 42% at 1 year, 62% at 5 years and 72% at 10 years and of requiring long-term renal replacement therapy was 10.6% at 10 years.

CONCLUSION

HTx provided good medium-term survival for patients with advanced heart failure, independent of its severity. The incidence of allograft vasculopathy was lower than reported previously but malignancy and CKD remain cause for concern.