Advances In Mechanical Circulatory Support Research Articles

Driveline Infection in Ventricular Assist Devices and Its Implication in the Present Era of Destination Therapy.

Advances in mechanical circulatory support devices provided the technology to develop long-term, implantable left ventricular assist devices as bridge to transplant, destination therapy, and in a lesser group of patients, as bridge to recovery. Despite the benefits from this innovative therapy, with their increased use, many complications have been encountered, one of the most common being infections. With the driveline acting as a portal to the exterior environment, an infection involving this structure is the most frequent one. Because patients with destination therapy are expected to receive circulatory support for a longer period of time, we will focus this review on the risk factors, prevention, and treatment options for driveline infections.

A 20-year multicentre outcome analysis of salvage mechanical circulatory support for refractory cardiogenic shock after cardiac surgery.

BackgroundRefractory post-cardiotomy cardiogenic shock (PCCS) is a relatively rare phenomenon that can lead to rapid multi-organ dysfunction syndrome and is almost invariably fatal without advanced mechanical circulatory support (AMCS), namely extra-corporeal membrane oxygenation (ECMO) or ventricular assist devices (VAD). In this multicentre observational study we retrospectively analyzed the outcomes of salvage venoarterial ECMO (VA ECMO) and VAD for refractory PCCS in the 3 adult cardiothoracic surgery centres in Scotland over a 20-year period.MethodsThe data was obtained through the Edinburgh, Glasgow and Aberdeen cardiac surgery databases. Our inclusion criteria included any adult patient from April 1995 to April 2015 who had received salvage VA ECMO or VAD for PCCS refractory to intra-aortic balloon pump (IABP) and maximal inotropic support following adult cardiac surgery.ResultsA total of 27 patients met the inclusion criteria. Age range was 34–83 years (median 51 years). There was a large male predominance (n = 23, 85 %). Overall 23 patients (85 %) received VA ECMO of which 14 (61 %) had central ECMO and 9 (39 %) had peripheral ECMO. Four patients (15 %) were treated with short-term VAD (BiVAD = 1, RVAD = 1 and LVAD = 2). The most common procedure-related complication was major haemorrhage (n = 10). Renal failure requiring renal replacement therapy (n = 7), fatal stroke (n = 5), septic shock (n = 2), and a pseudo-aneurysm at the femoral artery cannulation site (n = 1) were also observed. Overall survival to hospital discharge was 40.7 %. All survivors were NYHA class I-II at 12 months’ follow-up.ConclusionAMCS for refractory PCCS carries a survival benefit and achieves acceptable functional recovery despite a significant complication rate.

REFRACTORY CARDIOGENIC SHOCK REQUIRING EMERGENCY MECHANICAL CIRCULATORY SUPPORT AS BRIDGE TO DEFINITIVE THERAPY

Cardiogenic shock is defined as end-organ hypo-perfusion from decreased cardiac output. It is a known complication in patients presenting with acute myocardial infarction. Despite technological advances in mechanical circulatory support, mortality remains high. The challenge is appropriate selection

Coronary Artery Spasm is a Nightmare: A Rare Case of Multi Vessel Coronary Artery Spasm

Coronary artery spasm is not an uncommon event, but its pathophysiologic mechanisms followed by coronary artery vasospasm are not yet completely clarified. Coronary artery spasm can lead to sudden cardiac death due to ventricular arrhythmias or heart block. In the cases of cardiogenic shock secondly to severe coronary artery spasm, IABP is sufficient to support the patient’s hemodynamics, in the other cases of severe cardiogenic shock or cardiac arrest secondly to severe coronary artery spasm, IABP is not sufficient to support the patient’s hemodynamics and more advanced mechanical circulatory support devices such as veno-arterial ECMO should be performed. This report describes a case of severe multi vessel coronary artery spasm leading to cardiac arrest, cardiogenic shock and cardiac death although using the first-class heart circulation assist device, and illustrates IABP and ECMO support for acute cardiac dysfunction secondary to diffuse multivessel coronary artery spasm was fruitless labour sometimes.

Advanced mechanical circulatory support for refractory cardiogenic shock after cardiac surgery: An eleven-year experience in Edinburgh

Post-cardiotomy cardiogenic shock (PCCS) occurs in 2-6% of patients undergoing surgical revascularization or valvular surgery. Approximately 0.5-1.5% of patients are refractory to maximal inotropic and intra-aortic balloon counter pulsation (IABP) support. Refractory PCCS leads to rapid multi-organ dysfunction syndrome and is an almost universally fatal clinical state without advanced mechanical circulatory support (AMCS) i.e. extra-corporeal membrane oxygenation (ECMO) or ventricular assist devices (VAD). However, the associated major complications and cost related to such complex devices has led to centralization of such valuable services to only a few UK centers.

Report From a Forum on US Heart Allocation Policy

Since the latest revision in US heart allocation policy (2006), the landscape and volume of transplant waitlists have changed considerably. Advances in mechanical circulatory support (MCS) prolong survival, but Status 1A mortality remains high. Several patient subgroups may be disadvantaged by current listing criteria and geographical disparity remains in waitlist time. This forum on US heart allocation policy was organized to discuss these issues and highlight concepts for consideration in the policy development process. A 25-question survey on heart allocation policy was conducted. Among attendees/respondents were 84 participants with clinical/published experience in heart transplant representing 51 US transplant centers, and OPTN/UNOS and SRTR representatives. The survey results and forum discussions demonstrated very strong interest in change to a further-tiered system, accounting for disadvantaged subgroups and lowering use of exceptions. However, a heart allocation score is not yet viable due to the long-term viability of variables (used in the score) in an ever-developing field. There is strong interest in more refined prioritization of patients with MCS complications, highly sensitized patients and those with severe arrhythmias or restrictive physiology. There is also strong interest in distribution by geographic boundaries modified according to population. Differences of opinion exist between small and large centers.

Ventricular assist device selection: which one and when?

Advances in mechanical circulatory support have significantly expanded the treatment options for patients with heart failure, whether acute or chronic. There are numerous devices available that offer patients short-, intermediate-, and long-term duration of support depending on their clinical needs and cardiac recovery. Each device has its own technical considerations and the decision which device to use depends on several factors, including what is available, the degree of support required, and expected duration of support. Additional issues that need to be considered in choosing level of support include right heart function, respiratory failure, and multi-organ derangements. A widespread availability of short-term ventricular assist devices and timely institution for effective hemodynamic support will translate into improved patient outcomes whether that is successful transfer to a tertiary care facility or recovery of inherent cardiac function. Implantable ventricular assist devices have and will continue to evolve into smaller and more durable devices, and the future for patients with advanced heart failure looks ever-more promising.

Mechanical Circulatory Support for Patients With Acute Cardiogenic Shock.

Purpose Mechanical circulatory support (MCS) has been used for management of patients with acute cardiogenic shock with unsatisfactory results. Recent advent of short, mid and long term support devices has provided options to choose from according to the severity of shock, other comorbiditis and social support status of patients. However, indications, timing of intervention, duration of support, is not clearly delineated. This is a descriptive study of MCS for patients with acute cardiogenic shock. Methods Patients with acute cardiogenic shock who required MCS were retrospectively analyzed. Patients on intraaortic balloon pump (IABP) were enrolled when more advanced support was required. Patients with post cardiotomy shock were not included. Results From March 2010 to September 2013, 21 patients (15 men and 6 women; mean age, 47.6 ± 13.2 years; age range 21-71 years) were enrolled in the study. Etiology included acute myocardial infarction in 3 patients, decompensation of cardiomyopathy in 17 patients and unknown in 1. INTERMACS score was 1 in 18 patients and 2 in 3 patients. Initial devices were IABP, Impella 5.0 (Abiomed Inc., Danvers, MA), ECMO with femoral cannulation, central ECMO and HeartMateII (HMII, Thoratec Corp., Pleasanton, CA) in 8, 1, 4, 6 and 2 patients, respectively. After recovery from shock, 14 patients (67%) were bridged to HMII. Of those who were bridged to HMII, eight (57%) developed right ventricular failure (RVF). Of 8 patients with RVF post HMII, three were bridged to Htx, one was discharged with HMII, and four died due to acute RVF or multiple organ failure (MOF). Overall, survival to hospital discharge was achieved in 12 patients (57%). No patients weaned from MCS. Causes of death were acute RVF, MOF and stroke in 4, 3, 2 patients, respectively. Conclusions In our experience patients with severe cardiogenic shock who required advanced MCS could not wean from support. Stabilization of shock and bridging to HMII was achievable in two thirds of patients with various MCS options. Survival to hospital discharge was 57%. Development of RVF appeared to be the major determining factor for survival.

Short-Term Ventricular Assist Devices (Implantable and Percutaneous)

Short-term ventricular assist devices (VADs), percutaneous or surgical, are used in the settings of cardiogenic shock (CS) refractory to medical management, as bridges to myocardial recovery, heart transplantation, durable long-term devices, and in the aid of high-risk PCIs. Recent innovations in continuous-flow pump technology have contributed to the development of various short-term VADs with many impressive features. These include the CentriMag VAD and percutaneous VADs such as the Impella and TandemHeart VAD systems. With these and other advances in mechanical circulatory support, it is highly likely that the significant morbidity and mortality associated with CS are improving. However, clinical evidence supporting the use of these devices remains at the level of small case series. Rigorous clinical investigation is warranted to better quantify the contributions of device therapy to the management of CS.

Outcomes among patients requiring unplanned intra-aortic balloon pump reinsertion in cardiogenic shock

The intra-aortic balloon pump (IABP) is the most frequently utilized form of temporary mechanical circulatory support (MCS) in cardiogenic shock (CS). Withdrawal of IABP support may precipitate hemodynamic compromise such that IABP reinsertion is required. Data are scarce regarding the incidence and outcomes of patients undergoing IABP reinsertion in this setting. In this single-center retrospective study, we identified consecutive patients with CS in whom IABP reinsertion was required for hemodynamic decompensation. These patients were compared to matched controls in whom IABP withdrawal was successful. The primary outcome measure was in-hospital mortality, while the secondary outcome measure was a composite of in-hospital death, need for advanced MCS or heart transplantation, or discharge to hospice. Among 222 patients requiring IABP for CS, we identified 20 case patients (incidence=9.0%) and 38 matched controls. Baseline characteristics were similar for the two groups. In-hospital mortality was 70% in the reinsertion group and 31% in the controls (Odds ratio (OR) 5.2, 95% CI 1.4-18.9, P=0.005). The composite secondary endpoint was also significantly more common in the reinsertion group than the controls (85% vs. 42%; OR 7.3, 95% CI 1.6-33.1, P=0.002). On multivariate analysis, the need for IABP reinsertion was independently associated with in-hospital mortality (OR 7.7, 95% CI 1.6-36.2, P=0.01). Among patients with CS undergoing IABP removal, hemodynamic deterioration requiring IABP reinsertion is associated with extremely poor outcomes and, in appropriate patients, should prompt consideration of more advanced cardiac support.

Living With a Total Artificial Heart

Advances in mechanical circulatory support have reduced morbidity and mortality in end-stage heart failure. To date, there have been no published studies examining the psychosocial impact on patients who are supported with a total artificial heart (TAH-t). The purpose of this study was to describe the lived experience of patients currently supported by the TAH-t awaiting transplant. A qualitative method using Giorgi's modification of phenomenologic inquiry guided the investigation, which was conducted at a transplant center located in the mid-Atlantic region of the United States. A purposive sample was selected to reflect participants currently supported by the TAH-t. All participants (9 men, 1 woman; mean age, 48.2 years; nonischemic etiology, 80%) were in-patients on the progressive care unit at the time of the interview and had been supported for at least 30 days. The mean length of device therapy was 84.7 days (range, 33-245 days). Hope for the future was the overarching theme. Subthemes included reflections, for better or for worse, the secret club, and coping and adaptation. The patients reflected on severity of illness, progress, and expressed optimism. For better or for worse described how symptoms improved but were offset by restrictions imposed by the technology. The secret club described the support provided to help deal with their life situation. Coping and adaptation suggested that the patients came to terms with and accepted their circumstances. The findings will help clinicians understand patients experiencing a life-changing situation and implications for psychosocial interventions.

Left Thoracotomy HeartWare Implantation With Outflow Graft Anastomosis to the Descending Aorta

Advances in mechanical circulatory support have been critical in bridging patients awaiting heart transplantation. In addition, improvement in device durability has enabled left ventricular assist device therapy to be applied as destination therapy in those not felt to be transplant candidate. Because of the increasing complexity of patients, there continues to be a need for alternative strategies for device implantation to bridge high-risk patients awaiting heart transplantation, wherein the risks of numerous previous sternotomies may be prohibitive. We present a unique technique for placement of the HeartWare ventricular assist device via left anterior thoracotomy to the descending aorta in a patient awaiting heart transplantation with a history of multiple previous sternotomies.

Have We Given Up on Intra‐aortic Balloon Counterpulsation in Post–Myocardial Infarction Cardiogenic Shock?

The recently published Intra-aortic Balloon Pump in Cardiogenic Shock II (IABP-SHOCK II) trial concluded that intra-aortic counterpulsation (IACP) does not reduce 30-day mortality in patients with cardiogenic shock (CS) complicating acute myocardial infarction (AMI) for whom early revascularization strategy was planned. The study resulted in downgrading IACP in post-AMI CS patients by certain professional organizations like the European Society of Cardiology. Although this is the largest and most important CS study of this decade, it suffers from considerable shortcomings: (1) time intervals from chest-pain onset or AMI recognition to revascularization, enrollment, and IACP initiation are not disclosed; (2) 86.6% of the treatment arm initiated IACP only post-percutaneous coronary intervention (PCI), and 4.3 % did not receive IACP at all; (3) 17.4% of the control arm crossed over to IACP or other mechanical support, mostly due to protocol violations; (4) there is no adjudication of the mortality events; (5) follow-up is limited to 30 days; and (5) both methodology (especially IACP device size) and quality of IACP are not evaluated and documented. Because the study assessed mostly the efficacy and safety of IACP initiated post-PCI, the study conclusions should not be extrapolated to IACP pre-PCI or during PCI in CS. Moreover, IACP had a favorable effect on the mortality of younger patients. Intra-aortic counterpulsation should remain the first line of mechanical circulatory support for the hemodynamically compromised AMI patients with or without CS who are undergoing primary PCI. Early upgrade to more advanced mechanical circulatory support should be considered for selective suitable candidates who remain in refractory CS despite revascularization and IACP.

Cardiac transplantation: who to refer and when

For some patients with advanced heart failure, heart transplantation or mechanical circulatory support may be the only treatment left to improve quality life and survival. The timing of intervention is crucial, as patients should be referred before complications such as pulmonary hypertension, cardiorenal syndrome or liver failure develop.

Mechanical circulatory support for heart failure: past, present and a look at the future

Heart transplantation remains the gold standard for long-term cardiac replacement, but a shortage of donor organs will always limit this option. For both transplant-eligible and noneligible patients, advances in mechanical circulatory support have revolutionized the options for the management of end-stage heart failure, and this technology continues to bring us closer to a true alternative to heart transplantation. This review provides a perspective on the past, present and future of mechanical circulatory support and addresses the changes in technology, patient selection and management strategies needed to have this therapy fully embraced by the heart failure community, and perhaps replace heart transplantation either as the therapy of choice or as a strategy by which to delay transplantation in younger patients.

Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS)

The Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) is a North American national registry for mechanical circulatory support devices (MCSDs) that are used to treat advanced heart failure. Durable MCSDs that have been approved by the US Food and Drug Administration (FDA) are included in this registry; however, MCSDs that remain in FDA trials pending initial approval (ie, investigational device exemption [IDE] trials) and devices intended for short-term use (eg, Abiomed BVS 5000 ventricular assist device [Abiomed, Danvers, MA]) are not included. The purposes of this article are to present a developmental history of INTERMACS, to outline the collaboration of INTERMACS with various constituencies (eg, FDA, National Institutes of Health, Center for Medicare & Medicaid Services, industry, and physicians), to present a summary of information generated to date by INTERMACS, and to describe the future directions of INTERMACS. The concept of using mechanical circulatory assistance for more than a brief time after a cardiac operation dates to the early 1960s with the development of MCSDs that fit the definitions of counterpulsation devices (eg, the intra-aortic balloon pump), ventricular assist devices (VADs), and total artificial hearts.1–5 The development and initial clinical evaluation of these devices were regulated by individual academic medical center review groups that evolved into institutional review boards. The FDA entered this arena in 1976 with the advent of the FDA section for device regulation based on passage of the 1976 Medical Device Amendments.6 By 1991, groups including the Institute of Medicine foresaw the need for a detailed longitudinal database for patients receiving MCSDs, stating in an Institute of Medicine report that “patients should be followed through a registry for the remainder of their lives….”7 The committee further recommended that the National Heart, Lung, and Blood Institute support long-term follow-up studies. Eventually, a …

A stepwise progression in the treatment of cardiogenic shock

Cardiogenic shock remains a deadly complication of acute myocardial infarction (MI). Early revascularization, inotropic support, and intraaortic balloon counterpulsation are the mainstays of treatment, but these are not always sufficient. New mechanical approaches, both percutaneous and surgical, are available in this high-risk population. We present a case of a young woman with a massive anterior wall MI and subsequent cardiogenic shock who was treated with advanced mechanical circulatory support. This case serves as an illustration of the stepwise escalation of mechanical support that can be applied in a patient with an acute MI complicated by refractory cardiogenic shock. We also review the literature with regard to the use of percutaneous left ventricular assist devices in the setting of cardiogenic shock.

249 Living with a Total Artificial Heart

Advances in mechanical circulatory support have reduced morbidity and mortality in end stage heart failure.To date, there have been no published studies examining the psychosocial impact on patients who are supported with a total artificial heart (TAH-t). The purpose of this study is to describe the lived experience of patients currently supported by the TAH-t and awaiting transplant.

Mechanical Circulatory Support for Advanced Heart Failure

After nearly 50 years of clinical development, durable mechanical circulatory support (MCS) devices are widely available for patients with advanced heart failure. The field of circulatory support has matured dramatically in recent years, thanks to the advent of smaller, rotary pumps. The resulting transition away from older pulsatile devices has been swift. Accelerated use of continuous-flow left ventricular assist devices (LVADs) for long-term support has changed the face of advanced heart failure care. MCS candidate selection, risk stratification, and management strategies are evolving in tandem with new pump technology, producing a shift in the profiles of patients being considered for MCS. Timely referral for MCS evaluation and appropriate implantation now depends on familiarity with recent advances in pump design and clinical outcomes. This review, the first in a series on Advances in Mechanical Circulatory Support , will focus on durable intracorporeal LVADs used in adults with advanced heart failure, and highlight the evolution in both patients and technology. The modern era of cardiac surgery began in 1953 with the first clinical use of cardiopulmonary bypass, allowing increasingly complex operations and laying the foundation for circulatory assist devices.1 Shortly after its invention, the heart-lung machine began to be used to support patients with postcardiotomy cardiogenic shock to facilitate recovery after failed operations. By the 1960s, simple cardiac assist devices began to replace cardiopulmonary bypass for the treatment of postcardiotomy shock (Figure 1). The first clinical use of an implantable artificial ventricle was reported by Liotta et al2 in 1963. This primitive ventricular assist device (VAD) consisted of a pneumatically driven, tubular displacement pump with a valved conduit connecting the left atrium to the descending thoracic aorta. The pump provided partial left ventricular bypass for 4 days after postoperative cardiac arrest before the patient died of multiorgan failure. Inspired by …

Canadian Cardiovascular Society Focused Position Statement Update on Assessment of the Cardiac Patient for Fitness to Drive: Fitness Following Left Ventricular Assist Device Implantation

There have been significant advances in mechanical circulatory support during the past several years. Older pulsatile models of left ventricular assist devices (LVADs) (also known as VADs) have shown improved outcomes compared with medical therapy but have had limited durability and significant morbidity associated with their use. For this reason, Canadian Cardiovascular Society 2003 guidelines recommended permanent cessation of driving in these patients (for both private and commercial vehicle operation). However, recent advances with newer, continuous-flow devices have resulted in much lower rates of device-related complications and greater use of these devices for destination therapy. The majority of patients now are discharged home and lead active lives subsequently. Based on new evidence applied to the Society's “Risk of Harm” formula, it has been determined that patients with continuous-flow devices who are doing well 2 months post implantation are fit to hold noncommercial class drivers' licenses.