Hepatic dysfunction after left ventricular mechanical assist in patients with end-stage heart failure: role of inflammatory response and hepatic microcirculation

Predictors and Impact of Prolonged Vasoplegia After Continuous-Flow Left Ventricular Assist Device Implantation

Background

Vasoplegia after cardiac surgery is associated with adverse outcomes. However, the clinical effects of vasoplegia and the significance of its duration after continuous-flow left ventricular assist device (CF-LVAD) implantation are less known.

Objectives

This study aimed to identify predictors of and outcomes from transient vs prolonged vasoplegia after CF-LVAD implantation.

Methods

The study was a retrospective review of consecutive patients who underwent CF-LVAD implantation between January 1, 2005, and December 31, 2017. Vasoplegia was defined as the presence of all of the following: mean arterial pressure ≤65 mm Hg, vasopressor (epinephrine, norepinephrine, vasopressin, or dopamine) use for >6 hours within the first 24 hours postoperatively, cardiac index ≥2.2 L/min/m2 and systemic vascular resistance <800 dyne/s/cm5, and vasodilatory shock not attributable to other causes. Prolonged vasoplegia was defined as that lasting 12 to 24 hours; transient vasoplegia was that lasting 6 to <12 hours. Patient characteristics, outcomes, and risk factors were analyzed.

Results

Of the 600 patients who underwent CF-LVAD implantation during the study period, 182 (30.3%) developed vasoplegia. Mean patient age was similar between the vasoplegia and no-vasoplegia groups. Prolonged vasoplegia (n = 78; 13.0%), compared with transient vasoplegia (n = 104; 17.3%), was associated with greater 30-day mortality (16.7% vs 5.8%; P = 0.02). Risk factors for prolonged vasoplegia included preoperative dialysis and elevated body mass index.

Conclusions

Compared with vasoplegia overall, prolonged vasoplegia was associated with worse survival after CF-LVAD implantation. Treatment to avoid or minimize progression to prolonged vasoplegia may be warranted.

Hemocompatibility and biophysical interface of left ventricular assist devices and total artificial hearts

ABSTRACT

Over the past 2 decades, there has been a significant increase in the utilization of long-term mechanical circulatory support (MCS) for the treatment of cardiac failure. Left ventricular assist devices (LVADs) and total artificial hearts (TAHs) have been developed in parallel to serve as bridge-to-transplant and destination therapy solutions. Despite the distinct hemodynamic characteristics introduced by LVADs and TAHs, a comparative evaluation of these devices regarding potential complications in supported patients, has not been undertaken. Such a study could provide valuable insights into the complications associated with these devices. Although MCS has shown substantial clinical benefits, significant complications related to hemocompatibility persist, including thrombosis, recurrent bleeding, and cerebrovascular accidents. This review focuses on the current understanding of hemostasis, specifically thrombotic and bleeding complications, and explores the influence of different shear stress regimens in long-term MCS. Furthermore, the role of endothelial cells in protecting against hemocompatibility-related complications of MCS is discussed. We also compared the diverse mechanisms contributing to the occurrence of hemocompatibility-related complications in currently used LVADs and TAHs. By applying the existing knowledge, we present, for the first time, a comprehensive comparison between long-term MCS options.

Biomarkers in Patients with Left Ventricular Assist Device: An Insight on Current Evidence

Left ventricular assist devices (LVADs) have been representing a cornerstone therapy for patients with end-stage heart failure during the last decades. However, their use induces several pathophysiological modifications which are partially responsible for the complications that typically characterize these patients, such as right ventricular failure, thromboembolic events, as well as bleedings. During the last years, biomarkers involved in the pathways of neurohormonal activation, myocardial injury, adverse remodeling, oxidative stress and systemic inflammation have raised attention. The search and analysis of potential biomarkers in LVAD patients could lead to the identification of a subset of patients with an increased risk of developing these adverse events. This could then promote a closer follow-up as well as therapeutic modifications. Furthermore, it might highlight some new therapeutic pharmacological targets that could lead to improved long-term survival. The aim of this review is to provide current evidence on the role of different biomarkers in patients with LVAD, in particular highlighting their possible implications in clinical practice.

Risk of Liver Dysfunction After Left Ventricular Assist Device Implantation

BACKGROUND

Incident liver dysfunction after left ventricular assist device implantation has been previously associated with adverse outcomes, yet data on perioperative risk markers are sparse.

METHODS

We retrospectively reviewed consecutive patients undergoing continuous-flow left ventricular assist device implant between 2007 and 2017 at a single institution. Perioperative variables were evaluated by univariate modeling and adjusted for false discovery rate. Variables most significantly associated with incident Interagency Registry for Mechanically Assisted Circulatory Support-defined liver dysfunction (INT-LD) were evaluated using logistic regression and optimal cutpoints were defined. One-year survival was evaluated using Kaplan-Meier analysis.

RESULTS

We included 359 patients (79% male; mean age 59 ± 13 years; 46% ischemic; 64% destination therapy). Lower right ventricular stroke work index at the time of right heart catheterization, higher right atrial pressure 6 hours after right heart catheterization, higher preoperative total bilirubin, longer cardiopulmonary bypass time, and greater volume of intraoperative ultrafiltration were most strongly associated with incident INT-LD (adjusted P < .01 for each). Initial right ventricular stroke work index less than 460 mm Hg∗mL/m2 (odds ratio [OR] 4.6; 95% confidence interval [CI], 2.3 to 9.4), 6-hour right heart catheterization 14 mm Hg or greater (OR 4.3; 95% CI, 2.1 to 8.8), cardiopulmonary bypass time longer than 137 minutes (OR 3.3; 95% CI, 1.8 to 6.2; P < .01 for all), ultrafiltration more than 2.95 L (OR 3.7; 95% CI, 2 to 6.8), and total bilirubin greater than 1.4 mg/dL (OR 2.7; 95% CI, 1.4 to 5) were each strongly associated with risk of INT-LD, which was associated with decreased unadjusted 1-year survival (P < .001).

CONCLUSIONS

Right ventricular stroke work index, right heart catheterization, cardiopulmonary bypass time, and ultrafiltration were each more strongly associated with elevated risk of INT-LD after left ventricular assist device implant than total bilirubin. Therefore, optimization of right ventricular hemodynamics and minimizing cardiopulmonary bypass time and ultrafiltration could potentially reduce the risk of liver dysfunction, but these observations require prospective validation.

The rapid transformation of cardiac surgery practice in the coronavirus disease 2019 (COVID-19) pandemic: insights and clinical strategies from a centre at the epicentre

OBJECTIVES

The onset of the coronavirus disease 2019 (COVID-19) pandemic has forced our cardiac surgery programme and hospital to enact drastic measures that has forced us to change how we care for cardiac surgery patients, assist with COVID-19 care and enable support for the hospital in terms of physical resources, providers and resident training.

METHODS

In this review, we review the cardiovascular manifestations of COVID-19 and describe our system-wide adaptations to the pandemic, including the use of telemedicine, how a severe reduction in operative volume affected our programme, the process of redeployment of staff, repurposing of residents into specific task teams, the creation of operation room intensive care units, and the challenges that we faced in this process.

RESULTS

We offer a revised set of definitions of surgical priority during this pandemic and how this was applied to our system, followed by specific considerations in coronary/valve, aortic, heart failure and transplant surgery. Finally, we outline a path forward for cardiac surgery for the near future.

CONCLUSIONS

We recognize that individual programmes around the world will eventually face COVID-19 with varying levels of infection burden and different resources, and we hope this document can assist programmes to plan for the future.

The rapid transformation of cardiac surgery practice in the coronavirus disease 2019 (COVID-19) pandemic: Insights and clinical strategies from a center at the epicenter

Background

The onset of the coronavirus disease 2019 (COVID-19) pandemic has forced our cardiac surgery program and hospital to enact drastic measures that has forced us to change how we care for cardiac surgery patients, assist with COVID-19 care, and enable support for the hospital in terms of physical resources, providers, and resident training.

Methods

In this review, we review the cardiovascular manifestations of COVID-19 and describe our system-wide adaptations to the pandemic, including the use of telemedicine, how a severe reduction in operative volume affected our program, the process of redeployment of staff, repurposing of residents into specific task teams, the creation of operation room intensive care units, and the challenges that we faced in this process.

Results

We offer a revised set of definitions of surgical priority during this pandemic and how this was applied to our system, followed by specific considerations in coronary/valve, aortic, heart failure and transplant surgery. Finally, we outline a path forward for cardiac surgery for the near future.

Conclusions

We recognize that individual programs around the world will eventually face COVID-19 with varying levels of infection burden and different resources, and we hope this document can assist programs to plan for the future.

The Rapid Transformation of Cardiac Surgery Practice in the Coronavirus Disease 2019 (COVID-19) Pandemic: Insights and Clinical Strategies From a Center at the Epicenter

Background

The onset of the coronavirus disease 2019 (COVID-19) pandemic has forced our cardiac surgery program and hospital to enact drastic measures that has forced us to change how we care for cardiac surgery patients, assist with COVID-19 care, and enable support for the hospital in terms of physical resources, providers, and resident training.

Methods

In this review, we review the cardiovascular manifestations of COVID-19 and describe our system-wide adaptations to the pandemic, including the use of telemedicine, how a severe reduction in operative volume affected our program, the process of redeployment of staff, repurposing of residents into specific task teams, the creation of operation room intensive care units, and the challenges that we faced in this process.

Results

We offer a revised set of definitions of surgical priority during this pandemic and how this was applied to our system, followed by specific considerations in coronary/valve, aortic, heart failure and transplant surgery. Finally, we outline a path forward for cardiac surgery for the near future.

Conclusions

We recognize that individual programs around the world will eventually face COVID-19 with varying levels of infection burden and different resources, and we hope this document can assist programs to plan for the future.

Right ventricular failure following left ventricular assist device implantation is associated with a preoperative pro-inflammatory response

Background

Systemic inflammation during implant of a durable left ventricular assist device (LVAD) may contribute to adverse outcomes. We investigated the association of the preoperative inflammatory markers with subsequent right ventricular failure (RVF).

Materials and methods

Prospective data was collected on 489 patients from 2003 through 2017 who underwent implantation of a durable LVAD. Uni- and multivariable correlation with leukocytosis was determined using linear and binary logistic regression. The population was also separated into low (< 10.5 K/ul, n = 362) and high (> 10.5 K/ul, n = 127) white blood cell count (WBC) groups. Mantel-Cox statistics was used to analyze survival data.

Results

Postop RVF was associated with a higher preop WBC (11.3 + 5.7 vs 8.7 + 3.1) and C-reactive protein (CRP, 5.6 + 4.4 vs 3.3 + 4.7) levels. Multivariable analysis identified an independent association between increased WBC preoperatively with increased lactate dehydrogenase (LDH, P < 0.001), heart rate (P < 0.001), CRP (P = 0.006), creatinine (P = 0.048), and INR (P = 0.049). The high WBC group was more likely to be on preoperative temporary circulatory support (17.3% vs 6.4%, P < 0.001) with a trend towards greater use of an intra-aortic balloon pump (55.9% vs 47.2%, P = 0.093). The high WBC group had poorer mid-term survival (P = 0.042).

Conclusions

Postop RVF is associated with a preoperative pro-inflammatory environment. This may be secondary to the increased systemic stress of decompensated heart failure. Systemic inflammation in the decompensated heart failure may contribute to RVF after LVAD implant.

Artificial shear stress effects on leukocytes at a biomaterial interface

Medical devices, such as ventricular assist devices (VADs), introduce both foreign materials and artificial shear stress to the circulatory system. The effects these have on leukocytes and the immune response are not well understood. Understanding how these two elements combine to affect leukocytes may reveal why some patients are susceptible to recurrent device-related infections and provide insight into the development of pump thrombosis. Biomaterials-DLC: diamond-like carbon-coated stainless steel; Sap: single-crystal sapphire; and Ti: titanium alloy (Ti₆ Al₄ V) were attached to the parallel plates of a rheometer. Whole human blood was left between the two discs for 5 minutes at +37°C with or without the application of shear stress (0 s^-1 or 1000 s^-1 ). Blood was removed and used for complete blood cell counts, flow cytometry (leukocyte activation, cell death, microparticle generation, phagocytic ability, and reactive oxygen species [ROS] production), and the production of pro-inflammatory cytokines. L-selectin expression on monocytes was decreased when blood was exposed to the biomaterials both with and without shear. Applying shear stress to blood on a Sap and Ti surface led to activation of neutrophils shown as decreased L-selectin expression. Sap and Ti blunted the LPS-stimulated macrophage migration inhibitory factor (MIF) production, most notably when sheared on Ti. The biomaterials used here have been shown to activate leukocytes in a static environment. The introduction of shear appears to exacerbate this activation. Interestingly, a widely accepted biocompatible material (Ti) utilized in many different types of devices has the capacity for immune cell activation and inhibition of MIF secretion when combined with shear stress. These findings contribute to our understanding of the contribution of biomaterials and shear stress to recurrent infections and vulnerability to sepsis in some VAD patients as well as pump thrombosis.

Vasoplegia after implantation of a continuous flow left ventricular assist device: incidence, outcomes and predictors

Background

Vasoplegia after routine cardiac surgery is associated with severe postoperative complications and increased mortality. It is also prevalent in patients undergoing implantation of pulsatile flow left ventricular assist devices (LVAD). However, less is known regarding vasoplegia after implantation of newer generations of continuous flow LVADs (cfLVAD). We aim to report the incidence, impact on outcome and predictors of vasoplegia in these patients.

Methods

Adult patients scheduled for primary cfLVAD implantation were enrolled into a derivation cohort (n = 118, 2006–2013) and a temporal validation cohort (n = 73, 2014–2016). Vasoplegia was defined taking into consideration low mean arterial pressure and/or low systemic vascular resistance, preserved cardiac index and high vasopressor support. Vasoplegia was considered after bypass and the first 48 h of ICU stay lasting at least three consecutive hours. This concept of vasoplegia was compared to older definitions reported in the literature in terms of the incidence of postoperative vasoplegia and its association with adverse outcomes. Logistic regression was used to identify independent predictors. Their ability to discriminate patients with vasoplegia was quantified by the area under the receiver operating characteristic curve (AUC).

Results

The incidence of vasoplegia was 33.1% using the unified definition of vasoplegia. Vasoplegia was associated with increased ICU length-of-stay (10.5 [6.9–20.8] vs 6.1 [4.6–10.4] p = 0.002), increased ICU-mortality (OR 5.8, 95% CI 1.9–18.2) and one-year-mortality (OR 3.9, 95% CI 1.5–10.2), and a higher incidence of renal failure (OR 4.3, 95% CI 1.8–10.4). Multivariable analysis identified previous cardiothoracic surgery, preoperative dopamine administration, preoperative bilirubin levels and preoperative creatinine clearance as independent preoperative predictors of vasoplegia. The resultant prediction model exhibited a good discriminative ability (AUC 0.80, 95% CI 0.71–0.89, p <  0.01). Temporal validation resulted in an AUC of 0.74 (95% CI 0.61–0.87, p <  0.01).

Conclusions

In the era of the new generation of cfLVADs, vasoplegia remains a prevalent (33%) and critical condition with worse short-term outcomes and survival. We identified previous cardiothoracic surgery, preoperative treatment with dopamine, preoperative bilirubin levels and preoperative creatinine clearance as independent predictors.

Electronic supplementary material

The online version of this article (10.1186/s12871-018-0645-y) contains supplementary material, which is available to authorized users.

The Inflammatory Response to Ventricular Assist Devices

The therapeutic use of ventricular assist devices (VADs) for end-stage heart failure (HF) patients who are ineligible for transplant has increased steadily in the last decade. In parallel, improvements in VAD design have reduced device size, cost, and device-related complications. These complications include infection and thrombosis which share underpinning contribution from the inflammatory response and remain common risks from VAD implantation. An added and underappreciated difficulty in designing a VAD that supports heart function and aids the repair of damaged myocardium is that different types of HF are accompanied by different inflammatory profiles that can affect the response to the implanted device. Circulating inflammatory markers and changes in leukocyte phenotypes receive much attention as biomarkers for mortality and disease progression. However, they are seldom used to monitor progress during and outcomes from VAD therapy or during the design phase for new devices. Even the partial reversal of heart damage associated with heart failure is a desirable outcome from VAD use. Therefore, improved understanding of the interplay between VADs and the recipient's inflammatory response would potentially increase their uptake, improve patient lives, and fuel research related to other blood-contacting medical devices. Here we provide a review of what is currently known about inflammation in heart failure and how this inflammatory profile is altered in heart failure patients receiving VAD therapy.

Increased serum Wisteria floribunda agglutinin positive Mac-2 binding protein (Mac-2 binding protein glycosylation isomer) in chronic heart failure: a pilot study

BACKGROUND

Serum Wisteria floribunda agglutinin positive Mac-2 binding protein (WFA⁺-M2BP) or Mac-2 Binding Protein Glycosylation Isomer (M2BPGi) is a novel biomarker currently applied for evaluating hepatic fibrosis. The aim of this study was to evaluate the utility of serum WFA⁺-M2BP level as a biomarker in chronic heart failure (HF) patients with abnormal liver function.

METHODS AND RESULTS

Fifty chronic HF patients who underwent measurement of serum WFA⁺-M2BP were evaluated. The median value of serum WFA⁺-M2BP was 0.88 (interquartile range 0.48-1.29) cut-off index, and positive WFA⁺-M2BP (≥ 1.00 cut-off index) was observed in 22 (44%). Elevated WFA + -M2BP was associated with longer HF history, older age, female sex, valvular heart disease, decreased estimated glomerular filtration rate (eGFR), albumin, and cholinesterase. Stepwise multiple regression analysis showed that HF history, eGFR, and albumin were independent determinants of serum WFA⁺-M2BP values. Repeated measurements of serum WFA⁺-M2BP suggested association between the decrease of WFA⁺-M2BP and improvement of New York Heart Association (NYHA) functional class.

CONCLUSIONS

Elevation of serum WFA⁺-M2BP showed a high prevalence in chronic HF patients with abnormal liver function with relation to HF history, decreased hepatic protein synthesis, and renal dysfunction. Our results suggest that serum WFA⁺-M2BP may be a novel biomarker of chronic HF.

Evaluation of right ventricular function using liver stiffness in patients with left ventricular assist device

Objectives

Although right ventricular failure (RVF) is a major concern after left ventricular assist device (LVAD) implantation, methodologies to evaluate RV function remain limited. Liver stiffness (LS), which is closely related to right-sided filling pressure and may indicate RVF severity, could be non-invasively and repeatedly assessed using transient elastography. Here we investigated the suitability of LS as a parameter of RV function in pre- and post-LVAD periods.

Methods

The study included 55 patients with LVAD implantation as a bridge to transplantation between 2011 and 2015 whose LS was assessed using transient elastography.

Results

Seventeen patients presented with RVF, defined as requiring inotropic support for ≥30 days, nitric oxygen inhalation for ≥5 days, and/or mechanical RV support following LVAD implantation. Survival of patients with RVF was significantly worse compared with that of patients without RVF. Multivariate logistic regression analysis identified preoperative LS, LV diastolic dimension, RV stroke work index, and dilated phase of hypertrophic cardiomyopathy aetiology as significant risk factors; the combination of these parameters could improve predictive power of post-LVAD RVF with areas under the curve of 0.89. Furthermore, LS was significantly decreased by LV unloading and significantly correlated with right-sided filling pressure.

Conclusions

In addition to dilated hypertrophic cardiomyopathy aetiology, reduced RV stroke work index and small LV dimension, we demonstrated that non-invasively measured LS was a predictor of post-LVAD RVF and can be used as a parameter for the evaluation and optimization of RV function in the perioperative period.

Effects of Left Ventricular Assist Device Support on End-Organ Function in Patients With Heart Failure: Comparison of Pulsatile- and Continuous-Flow Support in a Single-Center Experience

BACKGROUND

Limited data exist about the effects of continuous-flow versus pulsatile-flow left ventricular assist devices (LVADs) on end-organ function. We hypothesized that a pulsatile Polvad MEV (PM) would result in outcomes similar to those of similarly ill patients implanted with a continuous-flow LVAD (Heartware [HW] or Heartmate II [HMII]). We aimed to compare renal, hepatic, and hematologic functions in the 1st 30 days of support.

METHODS

We retrospectively reviewed patients with 24 PM (21 M, 3 F; group P) and 15 HW and 5 HMII (20 M, 0 F); group C LVAD implantations from April 2007 to February 2014. Creatinine, bilirubin, aspartate (AST) and alanine (ALT) transaminases, hematocrit, platelet count, international normalized ratio (INR), and activated partial thromboplastin time (APTT) parameters were analyzed before implantation and during 30 days of support. Demographic parameters were similar.

RESULTS

No significant differences were found between the groups regarding baseline renal, hepatic, or hematologic function. Baseline INR and APTT were significantly higher in group P. Levels of creatinine were similar between groups. They increased from baseline to postoperative day (POD) 1 and then decreased. Bilirubin levels were insignificantly higher in group P. Transaminases were significantly higher in group P (AST in PODs 3-6, ALT in PODs 3-7). INR values were significantly higher at baseline and in POD 0. APTT values were insignificantly higher in group P.

CONCLUSIONS

The use of LVAD improved renal and hepatic function in our series. Patients in group P had more decreased hepatic function and presented slower regeneration.

New therapy, new challenges: The effects of long-term continuous flow left ventricular assist device on inflammation

Surgically implanted continuous flow left ventricular assist devices (CF-LVADs) are currently used in patients with end-stage heart failure (HF). However, CF-LVAD therapy introduces a new set of complications and adverse events in these patients. Major adverse events with the CF-LVAD include right heart failure, vascular dysfunction, stroke, hepatic failure, and multi-organ failure, complications that may have inflammation as a common etiology. Our aim was to review the current evidence showing a relationship between these adverse events and elevated levels of inflammatory biomarkers in CF-LVAD recipients.

Effects of Sevoflurane and Propofol on Organ Blood Flow in Left Ventricular Assist Devices in Pigs

The aim of this study was to assess the effect of sevoflurane and propofol on organ blood flow in a porcine model with a left ventricular assist device (LVAD). Ten healthy minipigs were divided into 2 groups (5 per group) according to the anesthetic received (sevoflurane or propofol). A Biomedicus centrifugal pump was implanted. Organ blood flow (measured using colored microspheres), markers of tissue injury, and hemodynamic parameters were assessed at baseline (pump off) and after 30 minutes of partial support. Blood flow was significantly higher in the brain (both frontal lobes), heart (both ventricles), and liver after 30 minutes in the sevoflurane group, although no significant differences were recorded for the lung, kidney, or ileum. Serum levels of alanine aminotransferase and total bilirubin were significantly higher after 30 minutes in the propofol group, although no significant differences were detected between the groups for other parameters of liver function, kidney function, or lactic acid levels. The hemodynamic parameters were similar in both groups. We demonstrated that, compared with propofol, sevoflurane increases blood flow in the brain, liver, and heart after implantation of an LVAD under conditions of partial support.

The carvacrol ameliorates acute pancreatitis-induced liver injury via antioxidant response

Acute pancreatitis (AP) may cause significant persistent multi-organ dysfunction. Carvacrol (CAR) possesses a variety of biological and pharmacological properties. The aim of the present study was to analyze the hepatic protection of CAR on AP induced by cerulein and to explore the underlying mechanism using in vivo studies. The rats were randomized into groups to receive (1) no therapy; (2) 50 µg/kg cerulein at 1-h intervals by four intraperitoneal injection (i.p.); (3) 50, 100 and 200 mg/kg CAR by one i.p.; and (4) cerulein + CAR after 2 h of cerulein injection. 12 h later, serum was provided to assess the blood AST, ALT and LDH values. Also, liver tissues were obtained for histological and biochemical measurements. Liver oxidative stress markers were evaluated by changes in the amount of lipid peroxides measured as MDA and changes in tissue antioxidant enzyme levels, SOD, CAT and GSH-Px. Histopathological examination was performed using scoring systems. Oxidative damage to DNA was quantitated in studied tissues of experimental animals by measuring the increase in 8-hydroxydeoxyguanosine (8-OHdG) formations. We found that the increasing doses of CAR decreased pancreatitis-induced MDA and 8-OH-dG levels. Moreover, the liver SOD, CAT and GSH-Px activities in the AP + CAR group were higher than that of the rats in the AP group. In the treatment groups, AST, ALT and LDH were reduced. Besides, necrosis, coagulation and inflammation in the liver were alleviated (p < 0.05). We suggest that CAR could be a safe and potent new drug candidate for treating AP through its antioxidative mechanism of action for the treatment of a wide range of disorders related to hepatic dysfunction.

Markers of inflammation in recipients of continuous-flow left ventricular assist devices

Although the newer continuous-flow left ventricular assist devices (CF-LVADs) provide clinical advantages over the pulsatile pumps, the effects of low pulsatility on inflammation are incompletely understood. The objective of our study was to examine the levels of inflammatory mediators in CF-LVAD recipients compared with both healthy control subjects and heart failure patients who were candidates for CF-LVAD support. Plasma levels of chemokines, cytokines, and inflammatory markers were measured in 18 CF-LVAD recipients and compared with those of 14 healthy control subjects and 14 heart failure patients who were candidates for CF-LVADs. The levels of granulocyte macrophage-colony stimulating factor, macrophage inflammatory proteins-1β, and macrophage-derived chemokine were significantly higher in the CF-LVAD group compared with both the heart failure and the healthy control groups, whereas no significant differences were observed between the healthy control subjects and the heart failure groups. Compared with the healthy controls, C-reactive protein, interferon gamma-induced protein-10, monocyte chemotactic protein-1, and interleukin-8 levels were significantly higher in both the CF-LVAD and heart failure groups, but no significant differences were observed between the CF-LVAD recipients and the heart failure patients. Inflammatory markers were elevated in CF-LVAD recipients compared with healthy control subjects and the heart failure patients. Further studies should investigate the clinical implications of elevated levels of inflammation in CF-LVAD recipients.

Liver stiffness measurements and short-term survival after left ventricular assist device implantation: A pilot study

BACKGROUND

Hepatic dysfunction can contribute to the clinical outcome of patients with end-stage chronic heart failure (HF). This pilot study evaluated the importance of liver stiffness (LS) measurements by acoustic radiation force impulse (ARFI) imaging elastography in patients with end-stage chronic HF who underwent left ventricular assist device (LVAD) implantation.

METHODS

The study enrolled 28 patients (23 men), mean age of 54 ± 11 years, with end-stage chronic HF selected for LVAD implantation. At baseline, all patients received LS measurements using ARFI elastography. Hepatic venous pressure gradient measurements and transjugular liver biopsies were performed in 16 patients. Liver stiffness was measured 21 days (Follow-up 1, n = 23) and 485 ± 136 days (Follow-up 2, n = 13) after LVAD implantation. Patients were classified according to their baseline LS into Group I (low baseline LS [no significant fibrosis = Metavir F < 2]) or Group II (high baseline LS [significant fibrosis = Metavir F ≥ 2]).

RESULTS

LS at baseline was higher in Group II than in Group I (p < 0.001) and decreased significantly after LVAD implantation (Follow-up 1, p = 0.002; Follow-up 2, p = 0.002). Baseline LS correlated with liver fibrosis (p = 0.049) and central venous pressure (p = 0.001). Non-survivors showed higher LS (p = 0.019), bilirubin (p = 0.018), Model for End-Stage Liver Disease score (p = 0.001), and liver fibrosis (p = 0.004) compared with the survivors. In the univariate analysis, LS was a significant factor (p = 0.017) in predicting survival after LVAD implantation.

CONCLUSIONS

ARFI elastography shows that LS is influenced by central venous congestion and histologic changes of the liver in patients with end-stage chronic HF. LS may predict the outcome in patients after LVAD implantation.

Novel method of evaluating liver stiffness using transient elastography to evaluate perioperative status in severe heart failure

BACKGROUND

The aim of the present study was to assess the efficacy of a non-invasive method, transient elastography (FibroScan), in measuring liver stiffness (LS), and whether LS can be used as a marker of cardiac - and hence perioperative - status.

METHODS AND RESULTS

Perioperative LS was prospectively measured using a FibroScan in 30 patients (21 male; 42.2 ± 13.3 years old) who underwent left ventricular assist device (LVAD) implantation. LS was checked pre- and postoperatively, then analyzed in regard to perioperative status. Preoperative LS was 13.3 ± 13.0 kPa (normal, <5.5 kPa), and was abnormal in 77% of patients. Four required bilateral VAD. LS in patients with bilateral VAD tended to be higher than in LVAD patients (25.1 ± 22.7 vs. 11.5 ± 10.5 kPa, P=0.051). No patient with LS ≤ 7.0 kPa required a right VAD. The incidence of major adverse events was lower in patients with LS ≤ 12.5 kPa (25% vs. 80%, P<0.05). There were also no mortalities among patients with LS ≤ 12.5 kPa.

CONCLUSIONS

LS was correlated with preoperative severity in patients with severe heart failure and reflected liver congestion, and may be useful to predict the requirement of right VAD, as well as postoperative complications in patients with LVAD implantation. This novel modality may be a useful non-invasive assessment method for management of severe heart failure.

Longitudinal assessment of inflammation in recipients of continuous-flow left ventricular assist devices

BACKGROUND

The long-term effects of continuous-flow left ventricular assist device (CF-LVAD) support on trends of inflammatory markers over time are unknown. We examined the hypothesis that the levels of inflammatory markers in CF-LVAD recipients are higher than in healthy controls and that these levels increase over time with long-term CF-LVAD support.

METHODS

We examined the levels of inflammatory markers longitudinally at baseline before CF-LVAD implantation and at 3, 6, and 9 months after implantation. We then compared the levels of inflammatory markers to those in a healthy control group.

RESULTS

Compared with baseline values before CF-LVAD implantation, left ventricular end-diastolic diameter (LVEDd) and left ventricular end-systolic diameter (LVESd) decreased significantly at 3, 6, and 9 months after CF-LVAD implantation. Brain natriuretic peptide (BNP) levels dropped significantly after CF-LVAD implantation but did not normalize. Improvements in ejection fraction at 3, 6, and 9 months after CF-LVAD implantation did not reach significance. Monocyte chemoattractant protein-1, interferon γ-induced protein, and C-reactive protein levels were higher in the CF-LVAD recipients at each of the time points (baseline before CF-LVAD implantation and 3, 6, and 9 months after implantation) compared with levels in healthy controls. In CF-LVAD recipients, serum interleukin-8, tumour necrosis factor-α, and macrophage inflammatory protein-β increased significantly at 9 months, and macrophage-derived chemokine increased at 6 months after CF-LVAD implantation compared with baseline.

CONCLUSIONS

Despite improvements in LV dimensions and BNP levels, markers of inflammation remained higher in CF-LVAD recipients. High levels of inflammation in CF-LVAD recipients may result from heart failure preconditioning or the long-term device support, or both. Because inflammation may be detrimental to CF-LVAD recipients, future studies should determine whether inflammatory pathways are reversible.

Effects of left ventricular assist device support on biomarkers of cardiovascular stress, fibrosis, fluid homeostasis, inflammation, and renal injury

OBJECTIVES

The purpose of this study was to examine changes in a broad panel of biomarkers following left ventricular assist device (LVAD) support in advanced heart failure (HF).

BACKGROUND

LVAD therapy mechanically unloads the failing heart and may result in reversal of certain aspects of the end-stage HF phenotype. Changes in markers of myocardial stress, fibrosis, inflammation, fluid homeostasis, and renal injury in this setting are unknown.

METHODS

Amino-terminal pro-B-type natriuretic peptide (NT-proBNP), galectin-3, ST2, copeptin, growth differentiation factor (GDF)-15, C-reactive protein (CRP), and neutrophil gelatinase associated lipocalin (NGAL) levels were measured in frozen plasma collected from 37 individuals prior to continuous flow LVAD implantation and a median of 136 (interquartile range: 94 to 180) days after implantation.

RESULTS

The median age of patients was 68 years old. LVAD therapy was associated with significant decreases in NT-proBNP (3,093 to 2,090 pg/ml; p = 0.02), ST2 (67.5 to 45.2 ng/ml, p <0.01), galectin-3 (24.7 to 22.0 ng/ml; p = 0.04), GDF-15 (3,232 to 2,613 ng/l;p <0.001), hs-CRP (22.4 to 11.9 mg/l; p = 0.01), and copeptin (103 to 94 pmol/l; p = 0.003) but not NGAL (132 to 135 ng/ml; p = 0.06). Despite improvement over time, absolute values of each biomarker remained extremely abnormal. Greater reductions in biomarkers were noted in individuals with >25% decrease in NT-proBNP concentrations but reached statistical significance only in the case of galectin-3 (p = 0.01).

CONCLUSIONS

The biomarker profile in patients after LVAD placement improves but nonetheless remains significantly abnormal. Our results suggest the need for targeted therapeutic interventions to mitigate such abnormalities and potentially increase rates of myocardial recovery.

Relationship between early inflammatory response and clinical evolution of the severe multiorgan failure in mechanical circulatory support-treated patients

Background. The mechanical circulatory support (MCS) is an effective treatment in critically ill patients with end-stage heart failure (ESHF) that, however, may cause a severe multiorgan failure syndrome (MOFS) in these subjects. The impact of altered inflammatory response, associated to MOFS, on clinical evolution of MCS postimplantation patients has not been yet clarified. Methods. Circulating cytokines, adhesion molecules, and a marker of monocyte activation (neopterin) were determined in 53 MCS-treated patients, at preimplant and until 2 weeks. MOFS was evaluated by total sequential organ failure assessment score (tSOFA). Results. During MCS treatment, 32 patients experienced moderate MOFS (tSOFA < 11; A group), while 21 patients experienced severe MOFS (tSOFA ≥ 11) with favorable (B group) or adverse (n = 13, C group) outcomes. At preimplant, higher values of left ventricular ejection fraction (LVEF) and estimated glomerular filtration rate (eGFR) were the only parameter independently associated with A group. In C group, during the first postoperative week, high levels of interleukin-8 (IL-8) and tumor necrosis factor (TNF)-α, and an increase of neopterin and adhesion molecules, precede tSOFA worsening and exitus. Conclusions. The MCS patients of C group show an excessive release to IL-8 and TNF-α, and monocyte-endothelial activation after surgery, that might contribute to the unfavourable evolution of severe MOFS.

Relationship between pre-implant interleukin-6 levels, inflammatory response, and early outcome in patients supported by left ventricular assist device: a prospective study

Purpose

The immune response is crucial in the development of multi-organ failure (MOF) and complications in end-stage heart failure patients supported by left ventricular assist device (LVAD). However, at pre-implant, the association between inflammatory state and post-LVAD outcome is not yet clarified. Aim of the study was to assess the relationship among pre-implant levels of immune-related cytokines, postoperative inflammatory response and 3-month outcome in LVAD-patients.

Methods

In 41 patients undergoing LVAD implantation, plasma levels of interleukin (IL)-6, IL-8, crucial for monocyte modulation, and urine neopterin/creatinine ratio (Neo/Cr), marker of monocyte activation, were assessed preoperatively, at 3 days, 1 and 4 weeks post-LVAD. MOF was evaluated by total sequential organ failure assessment (tSOFA) score. Intensive care unit (ICU)-death and/or post-LVAD tSOFA ≥11 was considered as main adverse outcome. Length of ICU-stay, 1 week-tSOFA score, hospitalisation and 3-month survival were considered additional end-points.

Results

During ICU-stay, 8 patients died of MOF, while 8 of the survivors experienced severe MOF with postoperative tSOFA score ≥11. Pre-implant level of IL-6 ≥ 8.3 pg/mL was identified as significant marker of discrimination between patients with or without adverse outcome (OR 6.642, 95% CI 1.201-36.509, p = 0.030). Patients were divided according to pre-implant IL-6 cutoff of 8.3 pg/ml in A [3.5 (1.2–6.1) pg/mL] and B [24.6 (16.4–38.0) pg/mL] groups. Among pre-implant variables, only white blood cells count was independently associated with pre-implant IL-6 levels higher than 8.3 pg/ml (OR 1.491, 95% CI 1.004–2.217, p = 0.048). The ICU-stay and hospitalisation resulted longer in B-group (p = 0.001 and p = 0.030, respectively). Postoperatively, 1 week-tSOFA score, IL-8 and Neo/Cr levels were higher in B-group.

Conclusions

LVAD-candidates with elevated pre-implant levels of IL-6 are associated, after intervention, to higher release of monocyte activation related-markers, a clue for the development of MOF, longer clinical course and poor outcome.

The biochemical and histological effects of lichens in normal and diabetic rats

Oxidative stress plays an important role in causing diabetes; however, no studies have thoroughly reported on the toxic and beneficial effects of lichen extracts in patients with diabetes mellitus (DM). This study covers a previously unrecognized effect of two well-known lichen species Cetraria islandica and Pseudevernia furfuracae in streptozotocin (STZ)-induced diabetes. In experimental design, control or diabetic rats were either untreated or treated with aqueous lichen extracts (250–500 mg/kg /day) for 2 weeks starting at 72 h after STZ injection. On day 14, animals were anaesthetized, and metabolic and biochemical parameters were appreciated between control and treatment groups. The histopathology of liver was examined using three different staining methods: hematoxylin–eosin (H&E), periodic acid Schiff (PAS), and reticulin and Sudan Black B. Our experimental data showed that increasing doses of C. islandica and P. furfuracae alone did not have any detrimental effects on studied parameters and the malondialdehyde level of liver. C. islandica extract showed positive results for antioxidant capacity compared to doses of P. furfuracae extract. However, the protective effect of C. islandica extract on diabetes-induced disorders and hepatic damages is still unclear. Moreover, unfortunately, animals subjected to DM therapy did not benefit from the usage of increasing lichen doses due to their unchanged antioxidant activity in tissues. The results obtained in present study suggested that C. islandica and P. furfuracae is safe but the power of these is limited because of intensive oxidative stress in liver of type 1 diabetic rats. It is also implied that C. islandica extract is especially suitable for different administration routes in DM animals.

Prediction of outcome in patients with liver dysfunction after left ventricular assist device implantation

Although postoperative liver dysfunction (LD) following left ventricular assist device (LVAD) implantation is associated with high mortality, outcome is difficult to predict in patients with liver dysfunction. We aimed to clarify factors affecting recovery from LD after VAD implantation. A total of 167 patients underwent LVAD implantation, of whom 101 developed early postoperative LD, defined as maximum total bilirubin (max T-bil) greater than 5.0 mg/dl within 2 weeks. We set two different end-points, unremitting LD, and 90-day mortality. The rates of early mortality (90 days) and recovery from LD were 36 % (36/101) and 72 % (73/101), respectively. Univariate analysis showed that preoperative body weight, preoperative mechanical support, preoperative T-bil and creatinine, left ventricular diastolic dimension, right VAD (RVAD) insertion, cardiopulmonary bypass time, postoperative cardiac index, and postoperative T-bil and central venous pressure (CVP) on postoperative day (POD) 3 (non-recovered vs recovered, 12.4 ± 4.5 vs 9.5 ± 3.6 mmHg) were higher in patients with unremitting LD. Preoperative T-bil, RVAD insertion, and T-bil and CVP on POD 3 (non-survivor vs survivor, 12.4 ± 4.4 vs 9.4 ± 3.6 mmHg) were also higher in non-survivors. Multivariate analysis demonstrated that CVP on POD 3 was predictive of recovery from postoperative LD (OR 0.730, P < 0.05) and 90-day mortality (OR 0.730, P < 0.05). A key outcome factor in patients who developed early postoperative LD after LVAD implantation was postoperative liver congestion with high CVP. To overcome postoperative LD, appropriate management of postoperative CVP level is important.

The natriuretic peptide time-course in end-stage heart failure patients supported by left ventricular assist device implant: focus on NT-proCNP

This study aimed to evaluate left ventricular assist device (LVAD) effects on natriuretic peptide (NP) prohormone plasma levels in end-stage heart failure (HF) patients, especially NT-proCNP, in order to better characterize the NP system during hemodynamic recovery by LVAD. HF patients (n=17, NYHA III-IV) undergoing LVAD were studied: 6 died of multi-organ failure syndrome (NS) and 11 survived (S). Total sequential organ failure assessment (t-SOFA) score and blood samples were obtained at admission (T1) and at 24, 72h and 1, 2, 4 weeks (T2-T6) after LVAD. In S, NT-proANP and NT-proCNP significantly increased at 24h after implantation, reaching a reduction to basal levels at 4 weeks following LVAD [NT-proANP: T1 vs. T2 p=0.017, NT-proCNP: T1 vs. T2 p=0.028, T1 vs. T3 p=0.043]. Elevated NT-proBNP plasma levels were observed at all times. In NS, NP plasma levels sustained higher with respect to S. No statistical variation was observed for NT-proCNP and NT-proANP in S and NS while NT-proBNP reached significant differences at T4 in NS. Considering S+NS, only NT-proCNP strongly correlated with t-SOFA score at T1 (rho=0.554, p=0.04) while subdividing patients NT-proCNP positively correlated in NS with t-SOFA score (rho=0.988, p=0.002) only at T4. In NS a correlation between NT-proCNP and NT-proBNP at T1 was observed (rho=-0.900, p=0.037). Both IL-6 and TNF-alpha sustained higher in NS patients than in S; in particular, statistical significance was observed for IL-6. The study of new peptides, such as NT-proCNP, would provide additional information for identifying patients who are more likely to recover.

The pharmacotherapy implications of ventricular assist device in the patient with end-stage heart failure

Advances in mechanical circulatory support, such as the use of ventricular assist devices (VADs), have become a means for prolonging survival in end-stage heart failure (HF). VADs decrease the symptoms of HF and improve quality of life by replacing some of the work of a failing heart. They unload the ventricle to provide improved cardiac output and end-organ perfusion, resulting in improvement in cardiorenal syndromes and New York Heart Association functional class rating. VADs are currently used asa bridge to heart transplantation, a bridge to recovery of cardiac function, or as destination therapy. Complications of VAD include bleeding, infections, arrhythmias, multiple organ failure, right ventricular failure, and neurological dysfunction. Patients with VAD have unique pharmacotherapeutic requirements in terms of anticoagulation, appropriate antibiotic selection, and continuation of HF medications. Pharmacists in acute care and community settings are well prepared to care for the patient with VAD. These patients require thorough counseling and follow-up with regard to prevention and treatment of infections, appropriate levels of anticoagulation, and maintenance of fluid balance. A basic understanding of this unique therapy can assist pharmacists in attending to the needs of patients with VAD.

Severity of oxidative stress and inflammatory activation in end-stage heart failure patients are unaltered after 1 month of left ventricular mechanical assistance

This study investigates the impact of early left ventricular (LV)-mechanical unloading on systemic oxidative stress and inflammation in terminal heart failure patients and their impact both on multi organ failure and on intensive care unit (ICU) stay. Circulating levels of urinary 15-isoprostane-F(2t) (8-epi-PGF2(α)) and pro-inflammatory markers [plasma interleukin (IL)-6, IL-8, and urinary neopterin, a monocyte activation index] were analyzed in 20 healthy subjects, 22 stable end-stage heart failure (ESHF) patients and in 23 LV assist device (LVAD) recipients at pre-implant and during first post-LVAD (PL) month. Multi-organ function was evaluated by total Sequential Organ Failure Assessment (tSOFA) score. In LVAD recipients the levels of oxidative-inflammatory markers and tSOFA score were higher compared to other groups. After device implantation 8-epi-PGF2(α) levels were unchanged, while IL-6, and IL-8 levels increased during first week, and at 1month returned to pre-implant values, while neopterin levels increased progressively during LVAD support. The tSOFA score worsened at 1 PL-week with respect to pre-implant value, but improved at 1 PL-month. The tSOFA score related with IL-6 and IL-8 levels, while length of ICU stay related with pre-implant IL-6 levels. These data suggest that hemodynamic instability in terminal HF is associated to worsening of systemic inflammatory and oxidative milieu that do not improve in the early phase of hemodynamic recovery and LV-unloading by LVAD, affecting multi-organ function and length of ICU stay. This data stimulate to evaluate the impact of inflammatory signals on long-term outcome of mechanical circulatory support.

Association of pre-operative interleukin-6 levels with Interagency Registry for Mechanically Assisted Circulatory Support profiles and intensive care unit stay in left ventricular assist device patients

BACKGROUND

Inflammatory mechanisms are associated with worse prognosis in end-stage heart failure (ESHF) patients who require left ventricular assist device (LVAD) support. Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) profiles describe patient condition at pre-implant and outcome. This study assessed the relationship among inflammation patterns and INTERMACS profiles in LVAD recipients.

METHOD

Thirty ESHF patients undergoing LVAD implantation as bridge to transplant were enrolled. Blood and urine samples were collected pre-operatively and serially up to 2 weeks post-operatively for assessment of inflammatory markers (plasma levels of interleukin [IL]-6, IL-8, IL-10, and osteopontin, a cardiac inflammatory-remodeling marker; and the urine neopterin/creatinine ratio, a monocyte activation marker). Multiorgan function was evaluated by the total sequential organ failure assessment (tSOFA) score. Outcomes of interest were early survival, post-LVAD tSOFA score, and intensive care unit (ICU) length of stay.

RESULTS

Fifteen patients had INTERMACS profiles 1 or 2 (Group A), and 15 had profiles 3 or 4 (Group B). At pre-implant, only IL-6 levels and the IL-6/IL-10 ratio were higher in Group A vs B. After LVAD implantation, neopterin/creatinine ratio and IL-8 levels increased more in Group A vs B. Osteopontin levels increased significantly only in Group B. The tSOFA score at 2 weeks post-LVAD and ICU duration were related with pre-implant IL-6 levels.

CONCLUSIONS

The INTERMACS profiles reflect the severity of the pre-operative inflammatory activation and the post-implant inflammatory response, affecting post-operative tSOFA score and ICU stay. Therefore, inflammation may contribute to poor outcome in patients with severe INTERMACS profile.

[Heart transplantation for patients on high emergency list with or without extracorporeal membrane oxygenation support]

OBJECTIVE

Severely impaired patients may wait in France on a special and temporary high emergency national list (called SU). Some of these patients need mechanical circulatory support with ECMO. In order to compare two groups of patients on SU, who acceeded to heart transplantation (HT) with or without ECMO, we reviewed retrospectively 20 consecutive patients transplanted on SU between January 2004 and September 2007 in Rennes.

PATIENTS AND METHODS

Among them, 10 were transplanted without ECMO and 10 others were implanted with a femoro-femoral ECMO before HT.

RESULTS

(1) Considering the group SU without pretransplantation ECMO: 2 years survival rate was 70%. Mean hospital stay was 26.4 days. Three patients were implanted with ECMO for graft dysfunction during postoperative course, without inherent complication. None graft dysfunction occurred after initial hospitalization; (2) considering the group SU with pretransplantation ECMO: 2 years survival rate was 90% (one early death). Mean hospital stay was 45 days with multiple complications due to the ECMO (leg's ischemia: n = 2; lung oedema: n = 1; lymphorrhea: n = 3, low flow requiring change of canulae: n = 1). None graft dysfunction occurred after initial hospitalization.

CONCLUSION

Although we didn't reach statistical significance, it seems that ECMO for patients in SU may be useful as bridge to transplant but with a higher morbidity than for similar patients transplanted without ECMO. Additional data from other transplant centers are needed to confirm our findings.

Early expression of pro- and anti-inflammatory cytokines in left ventricular assist device recipients with multiple organ failure syndrome

To assess whether the combined evaluation of total Sequential Organ Failure Assessment (t-SOFA) score and pro- and anti-inflammatory cytokine profiles early after left ventricular assist device (LVAD) implant discriminates patients at high risk for multiple organ failure syndrome (MOFS) in the first month post-LVAD, we analyzed plasma interleukin (IL)-6, IL-8, IL-10, IL-1ra, IL-1beta, tumor necrosis factor-alpha (TNF-alpha), and urine neopterin levels before (day 0) and at 4 hours, 1, 3, 7, 14, and 30 days after LVAD implant in 23 recipients. Eight patients died of MOFS between days 7 and 30 (nonsurvivors). At preimplant, only blood urea nitrogen and age were higher in nonsurvivors than survivors. At 4 hours, IL-8, IL-10, and IL1-ra levels were higher in nonsurvivors than in survivors; t-SOFA was also higher and peaked on day 3 in nonsurvivors. Only IL-8 levels on day 1 were significantly associated with a t-SOFA > or =10 on day 3 (odds ratio 1.10, 95% confidence interval 1.01-1.21, p = 0.04). Neopterin, marker of monocyte activation, increased significantly only in nonsurvivors (p < 0.001). These findings suggest that an activated inflammatory system soon after LVAD implant is implicated in MOFS development. Early monitoring of inflammatory mediators and t-SOFA score may be a valuable tool for outcome prediction in LVAD recipients.

Renal and hepatic function improve in advanced heart failure patients during continuous-flow support with the HeartMate II left ventricular assist device

BACKGROUND

The effects of continuous blood flow and reduced pulsatility on major organ function have not been studied in detail.

METHODS AND RESULTS

We evaluated renal (creatinine and blood urea nitrogen) and hepatic (aspartate transaminase, alanine transaminase, and total bilirubin) function in 309 (235 male, 74 female) advanced heart failure patients who had been supported with the HeartMate II continuous-flow left ventricular assist device for bridge to transplantation. To determine whether patients with impaired renal and hepatic function improve over time with continuous-flow left ventricular assist device support or whether there are any detrimental effects in patients with normal organ function, we divided patients into those with above-normal and normal laboratory values before implantation and measured blood chemistry over time during left ventricular assist device support. There were significant improvements over 6 months in all parameters in the above-normal groups, with values in the normal groups remaining in the normal range over time. Mean blood urea nitrogen and serum creatinine in the above-normal groups decreased significantly from 37+/-14 to 23+/-10 mg/dL (P<0.0001) and from 1.8+/-0.4 to 1.4+/-0.8 mg/dL (P<0.01), respectively. There were decreases in aspartate transaminase and alanine transaminase in the above-normal groups from 121+/-206 and 171+/-348 to 36+/-19 and 31+/-22 IU (P<0.001), respectively. Total bilirubin for the above-normal group was 2.1+/-0.9 mg/dL at baseline; after an acute increase at week 1, it decreased to 0.9+/-0.5 mg/dL by 6 months (P<0.0001). Both renal and liver values from patients in the normal groups remained normal during support with the left ventricular assist device.

CONCLUSIONS

The HeartMate II continuous-flow left ventricular assist device improves renal and hepatic function in advanced heart failure patients who are being bridged to transplantation, without evidence of detrimental effects from reduced pulsatility over a 6-month time period.

Effects of centrifugal, axial, and pulsatile left ventricular assist device support on end-organ function in heart failure patients

PURPOSE

Newer continuous-flow left ventricular assist devices (LVAD) have the advantage of smaller size and increased durability. Questions remain regarding the safety and effects of long-term nonpulsatile flow, despite some animal and human studies showing that end-organ function is well maintained with pulsatile or axial-flow devices. This study investigated whether centrifugal devices have similar effects on end-organ function.

METHODS

All patients who underwent LVAD implantation as bridge-to-transplant (BTT) therapy from January 2004 through May 2007 were reviewed. Excluded were patients on biventricular support, destination therapy, temporary support, and patients who died within 30 days after LVAD implantation. The centrifugal device was the VentrAssist (Ventracor Ltd, Sydney, Australia); axial, the HeartMate II; and pulsatile, the HeartMate XVE (Thoratec Corp, Pleasanton, CA).

RESULTS

During the study, 10 VentrAssist, 30 HeartMate II, and 18 HeartMate XVE devices were implanted. Among the 3 groups, age, gender, weight, duration of LVAD support, and cause of heart failure were comparable. No significant differences were found between groups with respect to baseline renal function, hepatic function, or hematologic function. At 1 and 3 months of follow-up, renal and hepatic function either improved or remained within normal limits in all groups.

CONCLUSIONS

Centrifugal, axial, and pulsatile LVADs all provide adequate circulatory support to maintain appropriate end-organ function in patients with end-stage heart failure. The advantages of the newer continuous-flow devices can be safely applied to an increasing number of patients. Long-term studies (>1 year) are needed to assess effects on end-organ function with continuous-flow devices, which may have important implications for use as destination therapy.

Complications in patients with ventricular assist devices

Heart failure affects more than 5 million people in the United States. The treatments of this disease include medical therapy, heart transplantation, and the implantation of ventricular assist devices. These devices are used in patients who are no longer responsive to conservative medical treatment, who are not candidates for a heart transplantation (destination therapy), who are awaiting a heart transplantation (bridge to transplantation), and who have acute heart failure and whose myocardial function is expected to return to normal (bridge to recovery). Although this therapy improves the mortality and quality of life among patients with heart failure, the devices also carry risk of multiple complications. This article discusses the acute and long-term complications of ventricular assist devices.

Pre-operative redox state affects 1-month survival in patients with advanced heart failure undergoing left ventricular assist device implantation

BACKGROUND

Left ventricular assist device (LVAD) implantation has proven effective as a bridge to transplantation in end-stage heart failure patients (ESHFPs), although survival during device support is critical. Oxidative stress has been implicated in the development of heart failure, but the influence of redox state on in-hospital post-LVAD outcome has not been clarified.

METHODS AND RESULTS

In this report we describe the oxidant/anti-oxidant profiles of 15 ESHFPs before LVAD placement, 5 of whom did not survive to 1 month, and in 30 subjects without cardiac disease, representing the control group.

CONCLUSIONS

Preliminary findings suggest that adequate activity of the GPx-1-based anti-oxidant system before device placement is associated with patient survival up to 1 month, despite comparable baseline oxidative stress in patients who both survived and died (within 2 weeks post-LVAD).

End-organ function in patients on long-term circulatory support with continuous- or pulsatile-flow assist devices

BACKGROUND

Limited data exist about the long-term effects of continuous-flow vs pulsatile-flow left ventricular assist devices (LVADs) on end-organ function.

METHODS

We reviewed the data of patients who underwent LVAD implantation at our institution between 1989 and 2004 and who were supported for >6 months. The continuous-flow (C-LVAD) group included 12 patients bridged to transplant with either a Jarvik 2000 or a Thoratec HeartMate II LVAD. The pulsatile (P-LVAD) group included 58 patients supported by a Thoratec HeartMate I LVAD. Follow-up was up to 15 months after LVAD implantation. Average duration of LVAD support was 370 +/- 182 days (range 180 to 754) for the C-LVAD group and 315 +/- 111 days (range 180 to 1,334) for the P-LVAD group.

RESULTS

Patients from both groups were comparable for age, gender, body weight, cardiac index, ejection fraction, creatinine, blood urea nitrogen, creatinine clearance, albumin, total bilirubin, and transaminase levels before implantation. C-LVAD patients had a lower pre-operative hemoglobin than did P-LVAD patients (10.5 +/- 1.7 g/dl vs 12.2 +/- 1.9 g/dl; p = 0.01). In both groups, albumin, blood urea nitrogen, creatinine, creatinine clearance, total bilirubin, and transminase levels either improved or stayed within the normal range at 6, 9, 12, and 15 months after LVAD implantation. Four of the 12 C-LVAD patients and 28 of the 58 P-LVAD patients underwent cardiac transplantation. Actuarial survival, censored for transplant, at 9, 12, and 15 months was 90% for the C-LVAD group and 88%, 78%, and 74% for the P-LVAD group (p = not statistically significant).

CONCLUSIONS

On the basis of these data, it appears that continuous- and pulsatile-type LVADs provide adequate blood flow to maintain proper end-organ function during prolonged circulatory support.

Left ventricular mechanical support with the Impella Recover left direct microaxial blood pump: a single-center experience

The Impella Recover left direct (LD) is a new intravascular microaxial blood pump, intended as a short-term mechanical support especially in case of acutely reduced left ventricular function. From September 2002 to October 2004, Impella was used to support 12 patients: six patients were supported as bridge-to-heart transplant (HTx); three patients were treated for fulminant acute myocarditis, and three patients for postcardiotomy low-output syndrome. Mean support time was 8.8 +/- 2.3 days. Overall mortality was 50%. Four patients were successfully HTxed; two patients supported as bridge-to-HTx died on left ventricular assist device. Two patients with myocarditis died of septic shock; two patients in the group of postcardiotomy died of multiorgan failure. The latter two patients were slowly weaned from the device, and at 3-months follow-up showed good improvement of the left ventricular function. Our initial experience with Impella Recover LD as mechanical support for patients in cardiogenic shock of various etiology is promising, yielding a good survival in a population of particularly compromised patients.

Importance of luxury flow for critically ill patients receiving a left ventricular assist system

The presence of a significant organ dysfunction does not immediately exclude patients from consideration for treatment with a left ventricular assist system (LVAS). However, in treating morbid circulatory shock patients with multiple organ failure, it is important to know the preoperative and postoperative factor or factors related to the recovery of the damaged organ function. In this study, we retrospectively analyzed patients receiving a LVAS at our institution and tried to determine the important factors related to the survival of patients with multisystem failure. Twenty-seven patients who underwent LVAS placement at Saitama Medical School Hospital between 1993 and 2003 were included in this study. The preoperative risk factors analyzed were renal dysfunction, respiratory dysfunction, hepatic dysfunction, the existence of active infection, and the combination of all four factors. As a postoperative factor, the pump flow index (mean LVAS pump flow during the first 2 weeks after LVAS surgery divided by the body surface area) was analyzed. None of the analyzed preoperative factors could predict survival after LVAS surgery, but a pump flow index of less than 2.5 l/min/m2 had a significant relationship with death after LVAS surgery. Further analysis revealed that all the patients with a pump flow index of 3.0 l/min/m2 or more could overcome preoperative organ dysfunction. Congestive heart failure patients with multisystem failure need luxury pump flow for successful LVAS surgery; this factor could be especially important in device selection and postoperative management.

Management of acute decompensated heart failure: treatment, controversy, and future directions

Acute decompensated heart failure is a growing public health care problem worldwide. The goals of treatment are immediate hemodynamic and symptomatic improvement followed by persistent follow-up with adherence to chronic heart failure guidelines. Controversies have centered around the best treatment options and avoidance of serious adverse events. This article highlights our current understanding of acute decompensated heart failure, discusses the controversy surrounding currently available new vasoactive treatments, and details future potential therapies.