Differential indication for mechanical circulatory support following heart transplantation

PURPOSE: We describe our experience with ventricular assist devices (VAD) in patients with cardiogenic shock refractory to pharmacological therapy and support using intraaortic balloon pump after cardiac transplantation. PATIENTS: Between July 1987 and August 1997, 848 patients underwent cardiac transplantation in our hospital. INTERVENTIONS: Fifteen patients (1.8%) needed mechanical circulatory support for refractory cardiac failure due to right heart failure (six patients), primary graft failure (three patients), and acute rejection (six patients). Three pump systems were used: Biomedicus Centrifugal Pump, Abiomed BVS 500, and Thoratec VAD. The choice of system depended on the indication and quality of each device. Seven patients (47%) could be weaned from the mechanical circulatory support (MCS) system and three patients (20%) are long-term survivors. RESULTS: All 15 patients developed at least one serious complication, such as multiorgan failure (MOF), liver failure, acute renal failure or sepsis. Twenty-five per cent had severe bleeding and 13% had neurological complication. Mortality was due mostly to MOF, MOF and sepsis or sepsis. The survivors had a CI greater than 2.2 l.min.m2, total bilirubin less than 1.0 U/1, and did not undergo resuscitation. CONCLUSIONS: Heart failure after cardiac transplantation severe enough to require MCS is currently associated with several major complications and high mortality (80%).     

Traitement de recours dans l’insuffisance cardiaque avancée

Heart failure with altered systolic function is a common disease with high mortality despite the improvements in medical management during the last decades. Beyond the diagnosis period of the disease, it is common to observe a clinical stability for years. As heart failure worsens, patients will suffer from an important functional limitation, systemic disorders (i.e., renal failure, malnutrition), especially in case of uncontrolled congestion. This is advanced heart failure, which is generally poorly recognized in clinical practice. However, it is a crucial turning point in patient’s medical history, as long-term management of these patients must be anticipated as soon as possible in order to judge their eligibility for cardiac transplantation or mechanical circulatory support. Indeed, psychosocial patient status, the comorbidity burden, and multiorgan failure due to heart failure will condition the results of these treatments. Acute heart failure with cardiogenic shock and multiorgan failure can lead to intensive care unit admission and invasive management of cardiac failure with mechanical support and/or emergency cardiac transplantation. In this review, we will define advanced heart failure syndrome. We discuss indications for admissions in intensive care unit for patients with cardiogenic shock, and supportive care that can be proposed for multiorgan failure. We will also discuss strategies and conditions required for long-term therapies such as cardiac transplantation and ventricular assist device implantation.     

Intra-aortic balloon counterpulsation as a therapy for shock

As early as 1967, IABC has been effectively used to support patients in cardiogenic shock. IABC provides the temporary circulatory assistance necessary to maintain coronary perfusion pressure, improve stroke volume and cardiac output, and decrease left ventricular preload and afterload. Until new forward flow devices are perfected and become globally available as mechanical assistance for pump failure, the intra-aortic balloon pump will continue to provide temporary mechanical circulatory assistance to support patients in cardiogenic shock until diagnosis of the underlying cause and definitive therapy can be determined.     

Percutaneous left ventricular assist devices for treatment of patients with cardiogenic shock

PURPOSE OF REVIEW: This review will discuss the rationale and clinical utility of percutaneous left ventricular assist devices in the management of patients with cardiogenic shock. RECENT FINDINGS: Left ventricular assist devices maintain partial or total circulatory support in case of severe left ventricular failure. Currently, two percutaneous left ventricular assist devices are available for clinical use: the TandemHeart and the Impella Recover LP system. Compared with the intraaortic balloon pump, the TandemHeart has been shown to significantly reduce preload and to augment cardiac output. In a randomized comparison between the TandemHeart and intraaortic balloon pump support in patients with cardiogenic shock, the improved cardiac index afforded by the left ventricular assist device resulted in a more rapid decrease in serum lactate and improved renal function. There were, however, no significant differences with respect to 30-day mortality, and complications including limb ischemia and severe bleeding were more frequent with left ventricular assist devices than intraaortic balloon pump support. SUMMARY: The advent of percutaneous left ventricular assist devices constitutes an important advance in the management of patients with severe cardiogenic shock and may serve as bridge to recovery or heart transplantation in carefully selected patients. While improvement of hemodynamic parameters appears promising, it remains to be determined whether this benefit translates into improved clinical outcome.     

Ventricular-assist devices for the treatment of chronic heart failure

The role of ventricular-assist devices in the management of end-stage heart failure is growing. Initially developed as a ‘bridge to transplantation’, they are now implanted permanently in patients who need cardiac replacement but are not candidates for cardiac transplantation (‘destination therapy’). Furthermore, observations from expert centers indicate that a significant proportion of patients under long-term mechanical assistance can be weaned from mechanical circulatory support after significant functional recovery of their native heart (‘bridge to recovery’). This review discusses the emerging roles of mechanical circulatory support and their direct implications in clinical practice. Evolution of devices, important aspects of candidate selection, challenging issues in the management of ventricular-assist device patients (infection, device malfunction, anticoagulation–thromboembolic complications, psychosocial issues and cost) and ongoing research targeting sustained myocardial recovery are discussed.     

Use of an implantable left ventricular assist device for irreversible ventricular fibrillation secondary to massive myocardial infarction — a case study

Mechanical circulatory support devices are currently being developed. The indications for their use are presently following acute myocardial infarction; in post cardiac-surgical cardiogenic shock; and as a mechanical ‘bridge’ to cardiac transplantation. Devices are being developed for permanent implantation in patients with end-stage left ventricular failure who are unacceptable for or denied transplantation. Intensive care nurses are required to care for patients who receive such mechanical support. These patients need intensive physical care with extensive nursing intervention and psychological support. The following case study describes the care of a patient who received an implantable left ventricular assist device (LVAD). The study illustrates the nursing care required in the management of such patients.     

Clinical review: mechanical circulatory support for cardiogenic shock complicating acute myocardial infarction

Acute myocardial infarction is one of the 10 leading reasons for admission to adult critical care units. In-hospital mortality for this condition has remained static in recent years, and this is related primarily to the development of cardiogenic shock. Recent advances in reperfusion therapies have had little impact on the mortality of cardiogenic shock. This may be attributable to the underutilization of life support technology that may assist or completely supplant the patient's own cardiac output until adequate myocardial recovery is established or long-term therapy can be initiated. Clinicians working in the intensive care environment are increasingly likely to be exposed to these technologies. The purpose of this review is to outline the various techniques of mechanical circulatory support and discuss the latest evidence for their use in cardiogenic shock complicating acute myocardial infarction.     

Ventricular-assist devices for the treatment of chronic heart failure

The role of ventricular-assist devices in the management of end-stage heart failure is growing. Initially developed as a 'bridge to transplantation', they are now implanted permanently in patients who need cardiac replacement but are not candidates for cardiac transplantation ('destination therapy'). Furthermore, observations from expert centers indicate that a significant proportion of patients under long-term mechanical assistance can be weaned from mechanical circulatory support after significant functional recovery of their native heart ('bridge to recovery'). This review discusses the emerging roles of mechanical circulatory support and their direct implications in clinical practice. Evolution of devices, important aspects of candidate selection, challenging issues in the management of ventricular-assist device patients (infection, device malfunction, anticoagulation-thromboembolic complications, psychosocial issues and cost) and ongoing research targeting sustained myocardial recovery are discussed.     

Cardiogenic shock: treatment

The treatment of cardiogenic shock complicating the acute coronary syndromes consists of medical therapy, percutaneous revascularization procedures, cardiac surgery, and the implantation of devices. Medical therapy is limited to different positive inotropic and vasoactive drugs, without any firm evidence of survival benefit using these drugs. Several new pharmacologic compounds are at different stages of clinical research, but are not yet routinely approved for the treatment of cardiogenic shock. The only evidence-based therapy with proven survival benefit is timely revascularization. Intra-aortic balloon pump counterpulsation maintains its central role as supportive treatment in cardiogenic shock patients. Anecdotal evidence is available about the use of ventricular assist devices, cardiac resynchronization therapy, and emergent heart transplantation.     

An unexpected surgical complication of ventricular assist device implantation identified by transesophageal echocardiography: a case report.

Ventricular assist devices are used for circulatory support for patients with cardiogenic shock and refractory heart failure. Although early and late complications of left ventricular assist devices have been reported, we report a rare surgical complication of a left ventricular assist device implantation. This unexpected surgical complication was accurately identified by transesophageal echocardiography.     

Management of cardiogenic shock attributable to acute myocardial infarction in the reperfusion era

Cardiogenic shock is the leading cause of death among patients hospitalized with acute myocardial infarction. It is defined as tissue hypoperfusion resulting from ventricular pump failure in the presence of adequate intravascular volume. Rapid assessment and triage of patients presenting in cardiogenic shock followed by appropriate institution of supportive therapies including vasopressor and inotropic agents, mechanical ventilatory support, and intra-aortic balloon pump counterpulsation are critical for effective management of these patients. However, emergency percutaneous coronary intervention or coronary artery bypass graft surgery is required to decrease mortality rates. Novel approaches, including inhibition of nitric oxide synthase and new mechanical support devices, may further decrease mortality rates, which remain high despite reperfusion therapy.     

Left heart and biventricular bypass

Various forms of circulatory assist devices are currently under investigation. Clinical use of ventricular bypass devices ranging from roller-pump-driven units to pneumatically powered VADs have been in use for several years. These devices are indicated for patients in cardiogenic shock following cardiac surgery or myocardial infarction when all other forms of conventional therapy have failed. Success, though modest, is encouraging in these patients with a dismal prognosis. An increasing role for the VAD may be found in supporting patients whose condition deteriorates while awaiting cardiac transplantation.     

Experience with percutaneous venoarterial cardiopulmonary bypass for emergency circulatory support

OBJECTIVE: Mechanical circulatory support can maintain vital organ perfusion in patients with cardiac failure unresponsive to standard pharmacologic treatment. The purpose of the current study was to report complication and survival rates in patients supported with emergency percutaneous venoarterial cardiopulmonary bypass because of prolonged cardiogenic shock or cardiopulmonary arrest. DESIGN: Retrospective clinical study. SUBJECTS: A total of 46 patients supported with venoarterial cardiopulmonary bypass, 25 because of cardiogenic shock unresponsive to pharmacologic therapy and 21 because of cardiopulmonary arrest unresponsive to standard advanced cardiac life support. RESULTS: In 41 of the 46 patients (89%), stable extracorporeal circulation was established; in five patients (11%), femoral cannulation was accomplished only after a surgical cutdown. A total of 28 patients were weaned from cardiopulmonary bypass (19 of 25 patients with cardiogenic shock vs. 9 of 21 patients with cardiopulmonary arrest, p =.03), and 13 patients had long-term survival (10 of 25 patients with cardiogenic shock vs. 3 of 21 patients with cardiopulmonary arrest, p =.1). Complications directly related to the use of cardiopulmonary bypass were found in 18 patients (39%), major complications related to femoral cannulation being the most common single cause for bypass-associated morbidity (eight patients, 17%). CONCLUSIONS: Long-term survival rates after emergency percutaneous cardiopulmonary bypass are encouraging in patients with an underlying cardiocirculatory disease amenable to immediate corrective intervention (angioplasty, surgery, transplantation).     

Microcirculation in cardiogenic shock: from scientific bystander to therapy target

Despite diagnostic and therapeutic improvements, mortality rates in patients with cardiogenic shock remain relatively high. Several studies showed that cardiogenic shock is associated with alterations in the microvascular circulation. These alterations may be reversed by extracorporeal support devices. A study by Munsterman and colleagues adds to the body of evidence showing that in patients deemed ready for discontinuing intra-aortic balloon pump (IABP) support, microcirculatory flow in small vessels increases after ceasing IABP therapy. This study not only highlights the need for optimal timing of weaning from IABP support but also supports recent findings that global hemodynamics do not necessarily result in changes of microvascular perfusion. All modalities of modern treatment in cardiogenic shock need to be evaluated for their effect on the microcirculation. Microcirculatory evaluations should be part of randomized controlled trial protocols. More effort is needed to improve outcomes and understand the microcirculation as a therapy target and not as a silent bystander.     

心脏移植术后原发性移植物衰竭行机械辅助治疗患者的护理

目的:分析及探讨机械辅助治疗在边缘心脏移植患者术后的应用价值。方法:回顾性分析长海医院2017年3月至2019年9月74例心脏移植患者的临床资料,所有患者均在术中行食道超声(TEE)检查发现移植物功能衰竭(表现为右心室功能障碍有5例,双心室功能障碍有9例),故在术中体外循环停机前给予机械辅助支持,其中ECMO辅助2例,...     

Mechanical circulatory assist devices

A ventricular assist device (VAD) is a heterotopic mechanical pump that augments or replaces the output of a failing ventricle. In the past decade, investigation and use of these devices has greatly improved our understanding of their potential roles and limitations. Successful univentricular and biventricular support has allowed for myocardial recovery and survival in several settings of intractable cardiogenic shock. The development of long-term VADs has allowed for successful bridging of patients to heart transplantation, and it has laid the groundwork for a permanent implantable replacement ventricle. In this review, we address indications, complications, management, and results of mechanical support in postcardiotomy, bridge to recovery, and bridge to transplantation settings. The tools to achieve ventricular support in the United States, and the VADs themselves, are described, with emphasis on unique features, indications, and limitations.     

Patient selection for cardiac transplant in 2012

Heart transplantation is the treatment of choice for many patients with advanced heart failure who remain symptomatic despite optimal medical therapy. Although heart transplantation results have improved over the past 10 years, careful patient selection and risk stratification of patients with advanced heart failure is paramount given limited allograft resources. Moreover, as alternative therapies to heart transplant, such as mechanical circulatory support, continue to improve in terms of patient outcomes, the selection strategy for those patients who would benefit from device support as destination therapy or bridge-to-transplant versus those patients who should proceed directly to transplant will continue to evolve. This review focuses on the optimal timing for heart transplant, risk stratification models for patient selection, as well as examining factors that continue to provoke controversy during the candidate selection process and factors that have changed from absolute to relative contraindications as the authors experience with cardiac transplantation continues to increase.     

Postoperative management of heart failure in pediatric patients

Low cardiac output syndrome (LCOS) is a well-described entity occurring in 25–65% of pediatric patients undergoing open-heart surgery. With judicious intensive care management of LCOS, most patients have an uncomplicated postoperative course, and within 24 h after cardiopulmonary bypass, the cardiac function returns back to baseline. Some patients have severe forms of LCOS not responsive to medical management alone, requiring temporary mechanical circulatory support to prevent end-organ injury and to decrease myocardial stress and oxygen demand. Occasionally, cardiac function does not recover and heart transplantation is necessary. Long-term mechanical circulatory support devices are used as a bridge to transplantation because of limited availability of donor hearts. Experience in usage of continuous flow ventricular assist devices in the pediatric population is increasing.     

Management of cardiogenic shock complicating myocardial infarction

Up to 10% of acute coronary syndromes are complicated by cardiogenic shock (CS) with contemporary mortality rates of 40–50%. The extent of ischemic myocardium has a profound impact on the initial, in-hospital, and post-discharge management and prognosis in this patient population. Individualized patient risk assessment plays an important role in determining appropriate revascularization, drug treatment with inotropes and vasopressors, mechanical circulatory support, intensive care support of other organ systems, hospital level of care triage, and allocation of clinical resources. This review will outline the underlying causes and diagnostic criteria, pathophysiology, and treatment of CS complicating acute coronary syndromes with a focus on (a) potential therapeutic issues from the perspective an interventional cardiologist, an emergency physician, and an intensive care physician, (b) the type of revascularization, and (c) new therapeutic advancements in pharmacologic and mechanical percutaneous circulatory support.     

Long-term use of the CentriMag® Ventricular Assist System as a right ventricular assist device: a case report

Right ventricular failure (RVF) following implantation of a left ventricular assist system (LVAS) is associated with high morbidity and mortality.( 1-4 ) Numerous centers have reported short-term use of the CentriMag (?) Ventricular Assist System (CVAS) (Levitronix LLC, Waltham, MA) for treatment of cardiogenic shock, decompensated heart failure and right ventricular failure (RVF) following LVAS implantation.( 5-9 ) The present report reviews the clinical course of a patient requiring long-term right ventricular support utilizing the CVAS, following a HeartMate (?) II LVAS (Thoratec Corp. Pleasanton, CA) implantation. Elevated cytotoxic antibody levels complicated the patient's treatment plan by precluding orthotropic heart transplantation. The CVAS operated for 304 days without mechanical difficulty until replaced with the HeartWare (?) Ventricular Assist System (HeartWare Inc. Miramar, FL).