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Heart failure (HF) is a frequent cause of inpatient admissions. The Framingham study in 1993 described the risk factors for heart failure. A recent study showed results of the five-year study showed an improved survival rate of 58% with the HeartMate 3 (vs. 44% with the HeartMate II). The American Heart Association reported the prevalence of HF to be 5.1 million in the United States in 2006. The worldwide prevalence has been estimated to be 23 million. HF can be categorized based on the left ventricular ejection fraction (LVEF) into systolic and diastolic HF. The former group includes patients with LVEF less than or equal to 40%, also termed heart failure with reduced ejection fraction (HFrEF). Heart failure with preserved ejection fraction (HFpEF) includes those with LVEF greater than or equal to 40%. This activity reviews the role of LVADs, their indications, and contraindications and highlights the role of the interprofessional team in the management of patients with end-stage cardiac disease. Objectives: Describe the indications of LVAD. Review the contraindications for LVAD. Summarize the complications of an LVAD. Explain the importance of improving care coordination among the interprofessional team to enhance the delivery of care for patients needing an LVAD. Access free multiple choice questions on this topic.

Heart failure (HF) is a frequent cause of inpatient admissions. The Framingham study in 1993 described the risk factors for heart failure and showed unacceptably high five-year mortality rates of 25% in men and 38% in women [1]. The American Heart Association reported the prevalence of HF to be 5.1 million in the United States in 2006 [2]. The worldwide prevalence has been estimated to be 23 million [3]. HF can be categorized based on the left ventricular ejection fraction (LVEF) into systolic and diastolic HF. The former group includes patients with LVEF less than or equal to 40%, also termed heart failure with reduced ejection fraction (HFrEF). Heart failure with preserved ejection fraction (HFpEF) includes those with LVEF greater than or equal to 40%. The multiple modalities of treatment available to treat HF include but are not limited to lifestyle modifications, pharmacologic agents, device therapies such as implantable cardioverter-defibrillator (ICD), and cardiac resynchronization therapy (CRT). At times, failure to improve could necessitate short-term mechanical circulatory support with the use of an intra-aortic balloon pump (IABP) or even extracorporeal membrane oxygenation (ECMO). However, a large population of patients continues to have advanced heart failure with worsening LVEF despite maximal therapy. Circulatory support with the use of a left ventricular assist device (LVAD) is an emerging field. The landmark REMATCH trial that compared LVADs with optimal medical therapy in class IV HF patients found a 48% reduction in mortality from any cause [4]. There was also a significant increase in the survival rates at one year (52% versus 25%) and two years (23% versus 8%). The definitive treatment for advanced HF (class II and IV) is cardiac transplantation [5]. However, with the limited number of donor hearts available, LVADs are life-saving.

Hematological Bleeding is the most common complication, occurring in both the perioperative period as well as later due to the need for anticoagulation with warfarin [13]. Cardiopulmonary bypass perioperatively alters the coagulation cascades and impairs the normal clotting mechanism, leading to bleeding. Also, bleeding has been attributed to the association of acquired von Willebrand disease in LVAD patients, typically more than a week after the procedure [14]. This is usually reversible if the LVAD is removed [15]. Bleeding may occur due to a leak at the pump site from polyester grafts in the conduits, the gastrointestinal mucosal surfaces, and intracranial vessels. The target INR in outpatients is usually 1.5 to 2.5 [16]. Thrombosis is another significant hematological complication Patients may develop pump thrombosis, embolic events, or stroke. It is usually due to subtherapeutic anticoagulation, atrial fibrillation, or infection that predisposes to a hypercoagulative state. Hemolysis is another possibility due to technical complications involving the design of the pump, malpositioned cannulae, or the development of heparin-induced thrombocytopenia and pump thrombosis [17]. Right Heart Failure Anatomic changes following LVAD placement cause right ventricular geometric alterations. With left ventricular (LV) unloading, the septum shifts to the left. The increased cardiac output from the LVAD results in an increased venous return to the right ventricle, which now has improved compliance. However, in patients with chronic heart failure, there is pre-existing pulmonary hypertension. This can result in right ventricular (RV) failure [18][19][18]. This may necessitate the use of milrinone to reduce pulmonary vascular resistance or epoprostenol as a selective pulmonary vasodilator [20][21][20]. In some circumstances, the use of RV mechanical support or ECMO may be required [22][23][22]. Infection The International Society of Heart and Lung Transplantation has classified infections based on their relationship to LVAD [24]. Infections usually occur at the pump site, pump pocket, or driveline. They typically present with localized warmth and erythema at the pump site, along with fever and leukocytosis. Ultrasound of the local region can diagnose such collections and also guide aspiration. Swabs are helpful in guiding treatment.

The International Society of Heart and Lung Transplantation has classified infections based on their relationship to LVAD [24]. Infections usually occur at the pump site, pump pocket, or driveline. They typically present with localized warmth and erythema at the pump site, along with fever and leukocytosis. Ultrasound of the local region can diagnose such collections and also guide aspiration. Swabs are helpful in guiding treatment. Most commonly, the gram-positive Staphylococcus aureus is isolated, but Enterococcus and other Staphylococcal species may be present. The most common gram-negative organism is Pseudomonas aeruginosa [25]. Aggressive treatment is indicated with the use of appropriate antibiotics to cover the involved pathogen. Surgical revision of the driveline away from the infection may be needed. However, the pump usually needs to be replaced. Surgical debridement may be needed for deeper infections, with the use of omental or muscle flaps or vacuum-assisted closure techniques described [26][27][28]. Infection is associated with significantly increased mortality rates. Hence, severe infections may warrant device explantation with the use of ECMO or cardiac transplantation as definitive treatment. Neurological Stroke is one of the most dreaded complications of LVAD placement. Both ischemic and hemorrhagic strokes are known to occur, either immediately postoperatively or after several months [29]. Strokes more commonly affect the right hemisphere, indicating a cardioembolic source [30]. Ischemic events have been attributed to partial obstruction of the inflow cannula, deformation of blood in the pump apparatus, outflow graft obstruction, and subtherapeutic anticoagulation or infection. The risk of hemorrhagic stroke is due to anticoagulation. Hence, a fine balance is necessary to achieve optimum anticoagulation. Arrhythmias

Stroke is one of the most dreaded complications of LVAD placement. Both ischemic and hemorrhagic strokes are known to occur, either immediately postoperatively or after several months [29]. Strokes more commonly affect the right hemisphere, indicating a cardioembolic source [30]. Ischemic events have been attributed to partial obstruction of the inflow cannula, deformation of blood in the pump apparatus, outflow graft obstruction, and subtherapeutic anticoagulation or infection. The risk of hemorrhagic stroke is due to anticoagulation. Hence, a fine balance is necessary to achieve optimum anticoagulation. Arrhythmias Ventricular arrhythmias are common after the procedure. Placement of the cannula can cause reentrant circuits [31]. Suction can lead to contact between the cannula and ventricular septum, triggering an arrhythmia. Significant changes in weight or the development of scar tissue can create malposition of the cannula, leading to arrhythmias [32]. Usually, the development of such arrhythmias can be managed by a change in device settings, such as reducing the speed of the LVAD to allow adequate ventricular filling. Management with a variety of medications is usually successful; however, refractory cases require catheter ablation or device exchange.

Dedicated LVAD setups are required for the management of patients who have received the devices. An integrated interprofessional approach between cardiac surgeons, intensivists, and special LVAD nurses is necessary for adequate monitoring and follow-up of patients to produce the best clinical outcome. Specialty-trained nurses managing patients with LVAD need to be familiar with expected complications and have open communication with the clinicians. The nursing staff should also assist in patient and family education in regard to the device, its purpose, and management requirements. [Level 5]