Recommendations for the use of mechanical circulatory support: device strategies and patient selection: a scientific statement from the American Heart Association

Mechanical Circulatory Support in the Treatment of Advanced Heart Failure

According to the Centers for Disease Control, heart failure (HF) remains a pervasive condition with high morbidity and mortality, affecting 5.8 million people in the United States and 23 million worldwide. For patients with refractory end-stage HF, heart transplantation is the "gold standard" for definitive treatment. However, the demand for heart transplantation has consistently exceeded the availability of donor hearts, with approximately 2331 orthotopic heart transplantations performed in the United States in 2015 despite an estimated 100 000 to 250 000 patients with New York Heart Association class IIIB or IV symptoms that are refractory to medical treatment, making such patients potential transplant candidates. As such, the need for mechanical circulatory support (MCS) to treat patients with end-stage HF has become paramount. In this review, we focus on the history, advancements, and current use of durable MCS device therapy in the treatment of advanced heart failure.

More than 20 years' experience of left ventricular assist device implantation at a non-transplant Centre

OBJECTIVES

Over recent decades implantable left ventricular assist devices (LVAD) have increased the possibility of improved survival in patients with advanced heart failure who also benefit from a better quality of life. The aim of this retrospective survey was to review the clinical results of LVAD implantation at a low-volume non-transplant centre (Linköping, Sweden) between 1993 and 2016. Our aim was also to assess the mortality and morbidity rates associated with implantation of three LVAD versions at our centre, and to compare our results with those from transplant centres.

DESIGN

A retrospective cohort study was performed examining the medical records of patients who had a HeartMate^® (HMI, HMII, HMIII) LVAD implanted as a bridge to heart transplantation (BTT) or as destination therapy (DT) at the University Hospital, Linköping.

RESULTS

Our main finding was a survival to heart transplantation rate of 82% among our BTT LVAD patients. The most common adverse event among our patients was infection. A higher frequency of temporary dialysis was seen in the HMII group compared to the HMI group, and the frequency of right ventricular failure was higher in our HMII material.

CONCLUSIONS

Our data suggests that patients requiring long-term LVAD support can safely have their device implanted and cared for at a non-transplant centre.

Trauma Resuscitation in a Left Ventricular Assist Device Patient: An Emergency Medicine Simulation Scenario

Heart failure is a leading cause of death worldwide. While heart transplantation is the most successful treatment for end-stage heart failure, the scarcity in donor hearts has ushered in the use of alternative therapies, such as the left ventricular assist device (LVAD). This patient population may present with low frequency, but they require disease-specific management. Learners may fine-tune these principles in a safe learning environment, such as a medical simulation lab. Here, we present a case in which a patient with a LVAD sustained serious traumatic injuries.

Screening for heart transplantation and left ventricular assist system: results from the ScrEEning for advanced Heart Failure treatment (SEE-HF) study

BACKGROUND

Heart transplantation (HTx) and implantable left ventricular assist systems (LVAS) improve outcomes in advanced heart failure but may be underutilized. We hypothesized that screening can identify appropriate candidates.

METHODS AND RESULTS

The ScrEEning for advanced Heart Failure treatment (SEE-HF) study was a multicentre prospective study screening patients with existing cardiac resynchronization therapy (CRT) and/or implantable cardioverter-defibrillator (ICD) for ejection fraction ≤40% and New York Heart Association (NYHA) class III-IV, and subsequently for guideline-based HTx and LVAS indication. Of 1722 (mean age 64 ± 14 years, 26% women) patients screened at eight centres in seven European countries, 121 (7.0%) were eligible and 99 (5.7%; mean age 61 ± 10 years, 19% women) patients were enrolled for detailed assessment. Twenty-six of the 99 enrolled patients (26%) were eligible for either HTx or LVAD (18 eligible for HTx; 7 eligible for LVAD; and 1 eligible for both). Eleven patients were listed for HTx and three received an LVAS. Eligible patients were 61 ± 8 years and 19% women, whereas those actually receiving intervention were 56 ± 8 years and 8% women.

CONCLUSIONS

Among patients with CRT and/or ICD, a minority have NYHA class III-IV heart failure and ejection fraction ≤40%. Among these, however, more than one-quarter have an unrecognized need for HTx or LVAS. When patients are offered intervention based on screening, many decline. Discrepancies exist between clinical and patient equipoise. Clinical Trial Registration ClinicalTrials.gov Unique Identifier: NCT00894387.

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.

Circulatory Flow Restoration Versus Cardiopulmonary Resuscitation: New Therapeutic Approach in Sudden Cardiac Arrest

Sudden cardiac arrest (SCA) remains a major problem for health authorities worldwide. Insufficiencies of current cardiopulmonary resuscitation (CPR) are most probably related to an inappropriate concept and applied methods that still concentrate on heartbeat as priority, instead of blood circulation to maintain organs' perfusions. The aim of this works is to propose a new therapeutic approach for SCA in a more effective and secure manner compared with current CPR methods. It correlates to a non-invasive circulatory flow restoration (CFR) device composed of a multilayered thoracic and infradiaphragmatic compartments that will be pulsated alternatively and in fixed frequencies using a low-pressure pneumatic generator. Proof-of-concept studies with different prototypes and methods of SCA, showed restoration of hemodynamics (BP ≥ 100 mm Hg) and increased urine output after 20 min of cardiac arrest in pediatric dogs and piglets. In summary, a CFR device can induce shear stress-mediated endothelial function to restore microcirculation and cellular metabolism. This represents a cost-effective method, predisposes to return of spontaneous circulation in case of SCA, adaptable for all age groups, in public and hospital environments.

Quality of Life, Depression, and Anxiety in Ventricular Assist Device Therapy: Longitudinal Outcomes for Patients and Family Caregivers

BACKGROUND

Patients who receive ventricular assist device (VAD) therapy typically rely on informal caregivers (family members or friends) to assist them in managing their device.

OBJECTIVE

The purpose of this study is to characterize changes in person-oriented outcomes (quality of life [QOL], depression, and anxiety) for VAD patients and their caregivers together from pre-implantation to 3 months post-implantation.

METHODS

This was a formal interim analysis from an ongoing prospective study of VAD patients and caregivers (n = 41 dyads). Data on person-oriented outcomes (QOL: EuroQol 5 Dimensions Visual Analog Scale; depression: Patient Health Questionnaire-8; anxiety: Brief Symptom Inventory) were collected at 3 time points (just prior to implantation and at 1 and 3 months post-implantation). Trajectories of change for patients and caregivers on each measure were estimated using latent growth modeling with parallel processes.

RESULTS

Patients' QOL improved significantly over time, whereas caregiver QOL worsened. Depression and anxiety also improved significantly among patients but did not change among caregivers. There was substantial variability in change on all outcomes for both patients and their caregivers.

CONCLUSIONS

This is the first quantitative study of VAD patient-caregiver dyads in modern devices that describes change in person-oriented outcomes from pre-implantation to post-implantation. This work supports the need for future studies that account for the inherent relationships between patient and caregiver outcomes and examine variability in patient and caregiver responses to VAD therapy.

Anticoagulation of Percutaneous Ventricular Assist Device Using Argatroban-Based Purge Solution: A Case Series

Impella devices are percutaneously inserted ventricular assist devices which require a continuous purge solution that contains heparin to prevent pump thrombosis and device failure. We describe 2 patients with heparin-induced thrombocytopenia (HIT) supported with an Impella device utilizing an argatroban-based purge solution. Case 1 involved an 83-year-old female with biventricular failure which resulted in right ventricle Impella support. The purge solution was changed to include argatroban due to concern of device clotting in the setting of HIT. Case 2 involved a 55-year-old male with worsening cardiogenic shock which resulted in left ventricle Impella support. Due to decreased purge flow rates and concerns for clotting, argatroban was added to the purge solution. Both patients' total argatroban regimens were monitored and adjusted by pharmacy, resulting in therapeutic anticoagulation without any major bleeding or thrombotic events. Subsequently, a protocol was designed and implemented. These case reports appear to demonstrate the safe and effective use of argatroban purge solutions for the necessary anticoagulation with an Impella device. Further studies are needed to confirm these results and determine the optimal dosing regimen.

Isolated Right Ventricular Stress (Takotsubo) Cardiomyopathy

A 79-year-old woman was admitted with a left femoral neck fracture and she immediately developed circulatory shock. Echocardiography showed a markedly enlarged right ventricle (RV) with systolic ballooning of the mid-ventricular wall and preserved contractility of the apex. The left ventricular (LV) motion was normal. Multi-detector-row computed tomography showed severe congestion of the contrast media in the right atrium with no forward flow to RV, but no pulmonary embolism. She was successfully treated with percutaneous veno-arterial extracorporeal membrane oxygenation. This case presented with acute, profound, but reversible RV dysfunction triggered by acute stress in a manner similar to that seen in LV stress cardiomyopathy.

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.

Expert consensus document: Echocardiography and lung ultrasonography for the assessment and management of acute heart failure

Echocardiography is increasingly recommended for the diagnosis and assessment of patients with severe cardiac disease, including acute heart failure. Although previously considered to be within the realm of cardiologists, the development of ultrasonography technology has led to the adoption of echocardiography by acute care clinicians across a range of specialties. Data from echocardiography and lung ultrasonography can be used to improve diagnostic accuracy, guide and monitor the response to interventions, and communicate important prognostic information in patients with acute heart failure. However, without the appropriate skills and a good understanding of ultrasonography, its wider application to the most acutely unwell patients can have substantial pitfalls. This Consensus Statement, prepared by the Acute Heart Failure Study Group of the ESC Acute Cardiovascular Care Association, reviews the existing and potential roles of echocardiography and lung ultrasonography in the assessment and management of patients with acute heart failure, highlighting the differences from established practice where relevant.

Renal dysfunction and chronic mechanical circulatory support: from patient selection to long-term management and prognosis

PURPOSE OF REVIEW

The purpose of this review is to describe the effects of mechanical circulatory support (MCS) on changes in kidney function and their relationship with mortality, with an additional focus on the evaluation and management of both preimplant and post-MCS renal dysfunction.

RECENT FINDINGS

Renal dysfunction is highly prevalent in patients referred for MCS and is associated with significantly increased mortality and postoperative acute kidney injury. Most patients, including those with renal dysfunction, experience marked early improvement in renal function with MCS, likely secondary to correction of the cardiogenic shock, volume overload, and neurohormonal activation characteristic of advanced heart failure. Currently, there are no diagnostic tests to definitively distinguish reversible forms of renal dysfunction likely to improve with MCS from irreversible renal dysfunction. Furthermore, the characteristic improvements in renal function observed in the early months of MCS are often transient, with subsequent recurrence of renal dysfunction with longer durations of support. Venous congestion, right ventricular dysfunction, and reduced pulsatility are potential mechanisms involved in resurgence of renal dysfunction following MCS.

SUMMARY

With the exponential growth of MCS, research endeavors to both improve understanding of the mechanisms behind observed changes in renal function and elucidate the device-related effects on the kidney are imperative.

Left Ventricular Assist Device Thrombosis Is Associated With an Increase in the Systolic-to-Diastolic Velocity Ratio Measured at the Inflow and Outflow Cannulae

OBJECTIVE

To determine whether the ratio of peak systolic-to-nadir diastolic velocity (S/D ratio) measured using Doppler at the left ventricular assist device (LVAD) inflow and outflow cannulae is associated with pump thrombosis and to determine whether there is an absolute decrease in the diastolic cannula velocities in LVAD thrombosis.

DESIGN

Retrospective chart review.

SETTING

University hospital.

PARTICIPANTS

Patients who underwent LVAD exchange.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Transesophageal echocardiograms were reviewed from all patients with the HeartMate II device (Thoratec Corporation, Pleasanton, CA) over a 6-year period and who underwent LVAD exchange for pump thrombosis. The following 3 time points were evaluated: (1) initial LVAD placement (prethrombosis), (2) thrombosis, and (3) exchanged LVAD placement (postthrombosis). Systolic and diastolic flow velocities were examined using pulse-wave spectral Doppler at the inflow and outflow cannulae, and the S/D ratio for each was determined. Statistical analysis was performed with SAS, version 9.4 (SAS Institute, Cary, NC), using 2-tailed tests and alpha = 0.05. Thirteen patients were included in the study. Significant differences were observed in S/D ratios among the 3 phases at both the inflow (p = 0.0234) and outflow (p = 0.0047) cannulae. Pairwise tests of the inflow cannulae showed that the mean S/D ratio at the time of thrombosis (mean ± standard deviation [SD], 4.29 ± 1.74) was significantly greater than the prethrombosis ratio (2.49 ± 0.65; p = 0.0069). Among outflow measurements, the mean S/D ratio at thrombosis (3.94 ± 1.34) was significantly higher than both the prethrombosis (2.63 ± 0.56; p = 0.0025) and postthrombosis (2.74 ± 0.83) (p = 0.0093) ratios. Decreases in diastolic velocities were not statistically significant at the inflow cannula. At the outflow cannula, there was a significant difference in diastolic velocity among the phases (p = 0.0233). Specifically, the postthrombosis diastolic measurements (41.50 ± 9.94) were significantly higher than both the prethrombosis (26.85 ± 10.13; p = 0.0140) and thrombosis (26.7 ± 15.35; p = 0.0151) values.

CONCLUSIONS

An increased S/D ratio measured with Doppler at the LVAD inflow and outflow cannulas may be associated with pump thrombosis. Decreased diastolic cannula velocities were not observed in LVAD thrombosis.

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

BACKGROUND

Refractory 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.

METHODS

The 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.

RESULTS

A 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.

CONCLUSION

AMCS for refractory PCCS carries a survival benefit and achieves acceptable functional recovery despite a significant complication rate.

Clinical Features of Acute and Fulminant Myocarditis in Children - 2nd Nationwide Survey by Japanese Society of Pediatric Cardiology and Cardiac Surgery

BACKGROUND

The 1st nationwide survey by the Japanese Society of Pediatric Cardiology and Cardiac Surgery of acute or fulminant myocarditis (AMC/FMC) in children revealed that the survival rate of FMC was only 51.6%. The 2nd nationwide survey was performed to evaluate the recent outcomes of pediatric myocarditis.Methods and Results:Questionnaires regarding patients aged ≤18 years with AMC/FMC during the period from January 2006 to December 2011 were mailed. A total of 221 cases (age 6.5±5.3 years, 116 boys and 105 girls) were reported. There were 145 (65.6%) and 74 cases (33.5%) of AMC/FMC, respectively; the type of myocarditis was not reported in the remaining 2 cases (0.9%). Viruses were identified in 56 cases (25.3%), including coxsackie B in 9 and influenza A in 8. Histopathology by either endomyocardial biopsy or autopsy was obtained in 38 cases (19.2%). Intravenous immunoglobulin was effective in 49 (34.3%) of 143 cases. Steroid therapy was effective in 20 (32.8%) of 61 cases. Mechanical circulatory support was given in 54 cases (24.4%) and 94.2% of them were patients with FMC. The survival rates for the whole study population, acute myocarditis, and FMC were 75.6%, 91.0%, and 48.6%, respectively.

CONCLUSIONS

The survival rate of children with myocarditis was almost identical to that of 10 years ago. (Circ J 2016; 80: 2362-2368).

Knowledge Gaps in Cardiovascular Care of Older Adults: A Scientific Statement from the American Heart Association, American College of Cardiology, and American Geriatrics Society: Executive Summary

The incidence and prevalence of most cardiovascular disorders increase with age, and cardiovascular disease (CVD) is the leading cause of death and major disability in adults aged 75 and older. Despite the effect of CVD on quality of life, morbidity, and mortality in older adults, individuals aged 75 and older have been markedly underrepresented in most major cardiovascular trials, and virtually all trials have excluded older adults with complex comorbidities, significant physical or cognitive disabilities, frailty, or residence in nursing homes and assisted living facilities. As a result, current guidelines are unable to provide evidence-based recommendations for diagnosis and treatment of older adults typical of those encountered in routine clinical practice. The objectives of this scientific statement are to summarize current guideline recommendations as they apply to older adults, identify critical gaps in knowledge that preclude informed evidence-based decision-making, and recommend future research to close existing knowledge gaps. To achieve these objectives, a detailed review was conducted of current American College of Cardiology/American Heart Association (ACC/AHA) and American Stroke Association (ASA) guidelines to identify content and recommendations that explicitly targeted older adults. A pervasive lack of evidence to guide clinical decision-making in older adults with CVD was found, as well as a paucity of data on the effect of diagnostic and therapeutic interventions on outcomes that are particularly important to older adults, such as quality of life, physical function, and maintenance of independence. Accordingly, there is a critical need for a multitude of large population-based studies and clinical trials that include a broad spectrum of older adults representative of those seen in clinical practice and that incorporate relevant outcomes important to older adults in the study design. The results of these studies will provide the foundation for future evidence-based guidelines applicable to older adults and enhance person-centered care of older individuals with CVD in the United States and around the world.

Acute Decompensated Heart Failure

Heart failure (HF) is a societal burden due to its high prevalence, frequent admissions for acute decompensated heart failure (ADHF), and the economic impact of direct and indirect costs associated with HF and ADHF. Common etiologies of ADHF include medication and diet noncompliance, arrhythmias, deterioration in renal function, poorly controlled hypertension, myocardial infarction, and infections. Appropriate medical management of ADHF in patients is guided by the identification of signs and symptoms of fluid overload or low cardiac output and utilization of evidence-based practices. In patients with fluid overload, various strategies for diuresis or ultrafiltration may be considered. Depending on hemodynamics and patient characteristics, vasodilator, inotropic, or vasopressor therapies may be of benefit. Upon ADHF resolution, patients should be medically optimized, have lifestyle modifications discussed and implemented, and medication concierge service considered. After discharge, a multidisciplinary HF team should follow up with the patient to ensure a safe transition of care. This review article evaluates the management options and considerations when treating a patient with ADHF.

The PulseCath iVAC 2L left ventricular assist device: conversion to a percutaneous transfemoral approach

AIMS

This technical report describes the essentials and practical implantation technique of the completely percutaneous PulseCath iVAC 2L left ventricular assist device.

METHODS AND RESULTS

Percutaneously inserted mechanical left ventricular assist devices are used for circulatory support during cardiogenic shock or high-risk percutaneous coronary interventions. The PulseCath concept is a novel pulsatile design that consists of an extracorporeal membrane pump connected to a large-bore catheter which is inserted across the aortic valve retrogradely into the left ventricle. A genuine intra-aortic balloon pump (IABP) console drives the pulsatile pump.

CONCLUSIONS

The percutaneous PulseCath iVAC 2L is driven by a genuine IABP console and provides more left ventricular support.

Sunshine Heart C-Pulse: device for NYHA Class III and ambulatory Class IV heart failure

Advanced heart failure (HF) patients not meeting criteria for ventricular assist device or heart transplant with life-limiting symptoms are limited to medical and resynchronization therapy. The Sunshine Heart C-Pulse, based on intra-aortic balloon pump physiology, provides implantable, on-demand, extra-aortic counterpulsation, which reduces afterload and improves cardiac perfusion in New York Heart Association Class III and ambulatory Class IV HF. The C-Pulse reduces New York Heart Association Class, improves 6-min walk distances, inotrope requirements and HF symptom questionnaires. Advantages include shorter operative times without cardiopulmonary bypass, no reported strokes or thrombosis and no need for anticoagulation. Driveline exit site infections, inability to provide full circulatory support and poor function with intractable arrhythmias remain concerns. Current randomized controlled studies will evaluate long-term efficacy and safety compared with medical and resynchronization therapy.

Current Status of Left Ventricular Assist Device Therapy

Congestive heart failure (HF) remains a serious burden in the Western World. Despite advances in pharmacotherapy and resynchronization, many patients have progression to end-stage HF. These patients may be candidates for heart transplant or left ventricular assist device (LVAD) therapy. Heart transplants are limited by organ shortages and in some cases by patient comorbidities; therefore, LVAD therapy is emerging as a strategy of bridge to transplant or as a destination therapy in patients ineligible for transplant. Patients initially ineligible for a transplant may, in certain cases, become eligible for transplant after physiologic improvement with LVAD therapy, and a small number of patients with an LVAD may have sufficient recovery of myocardial function to allow device explantation. This clinically oriented review will describe (1) the most frequently used pump types and aspects of the continuous-flow physiology and (2) the clinical indications for and the shift toward the use of LVADs in less sick patients with HF. Additionally, we review complications of LVAD therapy and project future directions in this field. We referred to the Interagency Registry for Mechanically Assisted Circulatory Support, landmark trials, and results from recently published studies as major sources in obtaining recent outcomes, and we searched for related published literature via PubMed. This review focuses primarily on clinical practice for primary care physicians and non-HF cardiologists in the United States.

In Vitro Thrombogenesis Resulting from Decreased Shear Rate and Blood Coagulability

In vitro antithrombogenic testing with mock circulation is a useful type of pre-evaluation in ex vivo testing of mechanical assist devices. For effective in vitro testing, we have been developing a clear quantitative thrombogenesis model based on shear stress and blood coagulability. Bovine blood was used as the test medium. The activating clotting time (ACT) was adjusted with trisodium citrate and calcium chloride from 200 to 1,000 seconds. The blood was then applied to a rheometer and subjected to shear at 50 to 2,880 s-1. Blood coagulation time and degree of thrombogenesis were measured by the torque sensor of the rheometer. Prothrombin time (PT) and activated partial thromboplastin time (APTT) of the test blood were also measured after the application of shear. Blood coagulation time increased, and the degree of thrombogenesis decreased, with increases in shear rate to between 50 and 2,880 s-1. for test bloods with ACTs of 200 to 250 seconds. An ACT of 200 to 250 seconds is thus appropriate for in vitro antithrombogenic testing under a shear rate of 2,880 s-1. APTT was prolonged, whereas PT did not change, with increasing shear rate: that is, increasing the shear rate reduced thrombogenesis related to the intrinsic clotting pathway. An ACT of 200 to 250 seconds was suitable for in vitro antithrombogenic testing, and increasing the shear stress generated in the mechanical assist device reduced thrombogenesis via the intrinsic clotting pathway.

Video capsule endoscopy in left ventricular assist device recipients with obscure gastrointestinal bleeding

AIM: To assess whether video capsule endoscopy (VCE) affects the outcomes of left ventricular assist devices (LVADs) recipients with gastrointestinal bleeding.

METHODS: This is a retrospective study of LVAD recipients with obscure gastrointestinal bleeding (OGIB) who underwent VCE at a tertiary medical center between 2005 and 2013. All patients were admitted and monitored with telemetry and all VCE and subsequent endoscopic procedures were performed as inpatients. A VCE study was considered positive only when P2 lesions were found and was regarded as negative if P1 or P0 were identified. All patients were followed until heart transplant, death, or the end of the study.

RESULTS: Between 2005 and 2013, 30 patients with LVAD underwent VCE. Completion rate of VCE was 93.3% and there was no capsule retention. No interference of VCE recording or the function of LVAD was found. VCE was positive in 40% of patients (n = 12). The most common finding was active small intestinal bleeding (50%) and small intestinal angiodysplasia (33.3%). There was no difference in the rate of recurrent bleeding between patients with positive and negative VCE study (50.0% vs 55.6%, P = 1.00) during an average of 11.6 ± 9.6 mo follow up. Among patients with positive VCE, the recurrent bleeding rate did not differ whether subsequent endoscopy was performed (50% vs 50%, P = 1.00).

CONCLUSION: VCE can be safely performed in LVAD recipients with a diagnostic yield of 40%. VCE does not affect recurrent bleeding in LVAD patients regardless of findings.

Knowledge Gaps in Cardiovascular Care of the Older Adult Population: A Scientific Statement From the American Heart Association, American College of Cardiology, and American Geriatrics Society

The incidence and prevalence of most cardiovascular disorders increase with age, and cardiovascular disease is the leading cause of death and major disability in adults ≥75 years of age; however, despite the large impact of cardiovascular disease on quality of life, morbidity, and mortality in older adults, patients aged ≥75 years have been markedly underrepresented in most major cardiovascular trials, and virtually all trials have excluded older patients with complex comorbidities, significant physical or cognitive disabilities, frailty, or residence in a nursing home or assisted living facility. As a result, current guidelines are unable to provide evidence-based recommendations for diagnosis and treatment of older patients typical of those encountered in routine clinical practice. The objectives of this scientific statement are to summarize current guideline recommendations as they apply to older adults, identify critical gaps in knowledge that preclude informed evidence-based decision making, and recommend future research to close existing knowledge gaps. To achieve these objectives, we conducted a detailed review of current American College of Cardiology/American Heart Association and American Stroke Association guidelines to identify content and recommendations that explicitly targeted older patients. We found that there is a pervasive lack of evidence to guide clinical decision making in older patients with cardiovascular disease, as well as a paucity of data on the impact of diagnostic and therapeutic interventions on key outcomes that are particularly important to older patients, such as quality of life, physical function, and maintenance of independence. Accordingly, there is a critical need for a multitude of large population-based studies and clinical trials that include a broad spectrum of older patients representative of those seen in clinical practice and that incorporate relevant outcomes important to older patients in the study design. The results of these studies will provide the foundation for future evidence-based guidelines applicable to older patients, thereby enhancing patient-centered evidence-based care of older people with cardiovascular disease in the United States and around the world.

Management of three cardiogenic pulmonary edemas occurring in a patient scheduled for left ventricular assist device implantation: indicators for determining left ventricular assist device pump speed

A male patient with Marfan syndrome underwent aortic root replacement and developed left ventricular (LV) failure. Four years later, he underwent aortic arch and aortic valve replacement. Thereafter, his LV failure progressed, and cardiogenic pulmonary edema (CPE) appeared, which we treated with extracorporeal LV assist device (LVAD) placement. Three months later, the patient developed aspiration pneumonia, which caused hyperdynamic right ventricle (RV) and CPE. We treated by changing his pneumatic LVAD to a high-flow centrifugal pump. A month later, he underwent thoracoabdominal aortic replacement. After four weeks, he developed septic thrombosis and LVAD failure, which caused CPE. We treated with LVAD circuit replacement and an additional membrane oxygenator. Four months later, he underwent DuraHeart(®) implantation. During this course, pulmonary artery wedge pressure (PAWP) varied markedly. Additionally, systolic pulmonary artery pressure (sPAP), left atrial diameter (LAD), RV end-diastolic diameter (RVEDD) and estimated RV systolic pressure (esRVP) changed with PAWP changes. In this patient, LV failure and hyperdynamic RV caused the CPEs, which we treated by adjusting the LVAD output to the RV output. Determining LVAD output, RV function and LV end-diastolic diameter are typically referred, and PAWP, LAD, RVEDD, and sPAP could be also referred.

Advanced mechanical circulatory support for post-cardiotomy cardiogenic shock: a 20-year outcome analysis in a non-transplant unit

Background

Post-cardiotomy cardiogenic shock (PCCS) has an incidence of 2–6 % after routine adult cardiac surgery. 0.5–1.5 % are refractory to inotropic and intra-aortic balloon pump (IABP) support. Advanced mechanical circulatory support (AMCS) can be used to salvage carefully selected number of such patients. High costs and major complication rates have lead to centralization and limited funding for such devices in the UK. We have looked the outcomes of such devices in a non-transplant, intermediate-size adult cardiothoracic surgery unit.

Methods

Inclusion criteria included any adult patient who had received salvage veno-arterial extra-corporeal membrane oxygenation (V-A ECMO) or a ventricular assist device (VAD) for PCCS refractory to IABP and inotropic support following cardiac surgery from April 1995-April 2015.

Results

Sixteen patients met the inclusion criteria. Age range was 34–83 years (median 71). There was a male predominance of 12 (75 %). Overall, 15 (94 %) had received ECMO of which, 10 (67 %) had received central ECMO and 5 (33 %) had received peripheral ECMO. One patient (6 %) had a VAD. The most common complication was haemorrhage. Stroke, femoral artery pseudo-aneurysm, sepsis and renal failure also occurred. Thirty-day survival was 37.5 %. Survival rate to hospital discharge was 31.2 %. All survivors had NYHA class I-II at 24 months follow-up.

Conclusions

Our survival rate is similar to that reported in several previous studies. However, the use of AMCS for refractory PCCS is associated with serious complications. The survivors in our cohort appear to maintain an acceptable quality of life.

Aspirin has limited ability to modulate shear-mediated platelet activation associated with elevated shear stress of ventricular assist devices

Continuous flow ventricular assist devices (cfVADs) while effective in advanced heart failure, remain plagued by thrombosis related to abnormal flows and elevated shear stress. To limit cfVAD thrombosis, patients utilize complex anti-thrombotic regimens built upon a foundation of aspirin (ASA). While much data exists on ASA as a modulator of biochemically-mediated platelet activation, limited data exists as to the efficacy of ASA as a means of limiting shear-mediated platelet activation, particularly under elevated shear stress common within cfVADs. We investigated the ability of ASA (20, 25 and 125 μM) to limit shear-mediated platelet activation under conditions of: 1) constant shear stress (30 dynes/cm(2) and 70 dynes/cm(2)); 2) dynamic shear stress, and 3) initial high shear exposure (70 dynes/cm(2)) followed by low shear exposure - i.e. a platelet sensitization protocol, utilizing a hemodynamic shearing device providing uniform shear stress in vitro. The efficacy of ASA to limit platelet activation mediated via passage through a clinical cfVAD system (DeBakey Micromed) in vitro was also studied. ASA reduced platelet activation only under conditions of low shear stress (38% reduction compared to control, n=10, p<0.004), with minimal protection at higher shear stress and under dynamic conditions (n=10, p>0.5) with no limitation of platelet sensitization. ASA had limited ability (25.6% reduction in platelet activation rate) to modulate shear-mediated platelet activation induced via cfVAD passage. These findings, while performed under "deconstructed" non-clinical conditions by utilizing purified platelets alone in vitro, provide a potential contributory mechanistic explanation for the persistent thrombosis rates experienced clinically in cfVAD patients despite ASA therapy. An opportunity exists to develop enhanced pharmacologic strategies to limit shear-mediated platelet activation at elevated shear levels associated with mechanical circulatory support devices.