American Association for Thoracic Surgery/International Society for Heart and Lung Transplantation guidelines on selected topics in mechanical circulatory support

Omentoplasty for ventricular assist device infections: Encouraging outcomes

Background

LVAD infections are associated with substantial morbidity and mortality. We explored the impact of surgical Omentoplasty (OMP) added to Incision and Debridement (I&D) plus Antibiotic therapy (AB) on survival and infection-related readmissions in patients with LVAD infections.

Methods

Thirty-three patients with deep LVAD-specific infections were studied over a period of 12 years. Survival and readmissions for recurrent infection in subjects receiving I&D and ABs alone (Group A, n = 15) were compared to those in whom OMP was added to I&D and ABs (Group B, n = 18).

Results

Baseline characteristics were similar between groups, as well as infectious organisms. Two-year survival was significantly improved in Group B (OMP + I&D + ABs) as compared to Group A (I&D + ABs without OMP) [77% vs. 7%; p < 0.001]. Recurrent infection-related readmissions were notably lower in Group B compared to Group A (0.18 vs. 0.24 admissions/patient-year), with a significant reduction within Group B following the application of OMP (0.13 to 0.06 admissions/patient-year). Following OMP, intravenous (IV) antibiotics were successfully replaced with oral long-term ABs in the 78% of patients. No long-term antibiotic-related complications were noted.

Conclusion

This report, comprising the most extensive such experience to date, indicates that combining surgical Omentoplasty (OMP) with incision and debridement (I&D) plus antibiotic (AB) treatment is remarkably effective for suppressing deep LVAD infections, improving survival and decreasing infection-related readmissions. Filling the open space around an implanted LVAD with highly vascularized omentum, as a living tissue with anti-infective properties, appears to be effective for improving outcomes with LVAD infections.

Safety of enoxaparin in patients implanted with continuous flow left ventricular assist devices

BACKGROUND

The objective of this study is to determine the incidence of major bleeding events in patients implanted with continuous flow left ventricular assist devices (CF-LVADs) bridged with enoxaparin (LMWH) compared to intravenous unfractionated heparin (IV UFH) for a subtherapeutic INR on warfarin.

METHODS

A single-center, retrospective, cohort study was conducted including patients with CF-LVADs implanted between January 1, 2012 and July 1, 2020 who received at least one inpatient dose or outpatient prescription for LMWH or IV UFH at least 60 days after CF-LVAD implantation. The primary endpoint was the incidence of major bleeding.

RESULTS

In total, 176 orders were screened and 90 orders in 62 unique patients were included. Major bleeding and thromboembolic events occurred in 1 (2.5%) versus 4 (10.0%) orders (p = 0.36) and 3 (7.5%) versus 1 (2.5%) orders (p = 0.62) in the LMWH and IV UFH groups, respectively. One patient had a fatal thromboembolic event in each group. More patients receiving IV UFH had minor bleeding events (10 [25.0%] vs. 3 [7.5%]; p = 0.03).

CONCLUSIONS

There was no difference between bleeding and thromboembolic events in patients implanted with CF-LVADs prescribed LMWH or IV UFH for bridging of subtherapeutic INRs. Larger prospective randomized data are needed to validate these findings.

Warfarin and Aspirin Versus Warfarin Alone in Patients With HeartMate 3 Left Ventricular Assist Device: A Systematic Review and Meta-Analysis

BACKGROUND AND AIMS

HeartMate 3 (HM3), a fully magnetically levitated ventricular assist device (LVAD), has been associated with reduced thromboembolic events compared to HeartMate II. However, bleeding events remained significant. Among patients undergoing HM3 implantation, the standard antithrombotic regimen comprises both warfarin and aspirin (ASA), but there is a lack of evidence on the optimum antithrombotic therapy. We performed a systematic review and meta-analysis assessing the impact of combined ASA and warfarin therapy compared to warfarin alone on the incidence of non-surgical bleeding events in patients with HM3 LVAD.

METHODS

MEDLINE, Embase, and Cochrane databases were searched for randomized controlled trials (RCTs) and observational studies comparing warfarin alone with warfarin combined with ASA in patients with HM3 LVAD. Binary endpoints were analyzed using computed risk ratios (RRs) with 95% confidence intervals (CIs). A random-effect model was applied for all endpoints.

RESULTS

Five studies (one RCT and four observational) encompassing 869 patients were included, with 424 (48.8%) prescribed warfarin alone, and 662 (76.2%) being male. Compared with the combined anticoagulation regimen, warfarin alone significantly reduced non-surgical bleeding (RR 0.30; 95% CI 0.09-0.95; p = 0.04) and gastrointestinal bleeding (RR 0.26; 95% CI 0.12-0.58; p < 0.001). There was no statistically significant difference between the groups for all-cause mortality (RR 1.02; 95% CI 0.45-2.32; p = 0.963).

CONCLUSIONS

Our findings indicate that the use of warfarin alone for anticoagulation in HM3 patients is associated with a reduced risk of bleeding events when compared to the combined therapy with ASA.

Temporarily Reversing Warfarin With Low-Dose 4-Factor Prothrombin Complex Concentrate in Left Ventricular Assist Device Patients Undergoing an Invasive Procedure

BACKGROUND

American Association for Thoracic Surgery and The International Society for Heart and Lung Transplantation (AATS/ISHLT) guidelines recommend warfarin in patients with continuous-flow left ventricular assist devices (LVADs) to reduce the risk of device thrombosis and systemic embolization. Left ventricular assist device patients often undergo elective and emergent procedures that require interrupted anticoagulation. Data and experience vary on the optimal strategy to rapidly reverse warfarin in LVAD patients when an emergent procedure is planned.

OBJECTIVE

The purpose of this study was to describe the use of 4-factor prothrombin complex concentrate (PCC4) for warfarin reversal in patients with LVADs undergoing elective and emergent procedures.

METHODS

This retrospective, single-center, cohort review describes the use of PCC4 in patients with LVADs who require warfarin reversal for elective or emergent procedures. The primary outcome was a composite incidence of pump thrombosis, venous thromboembolism, and ischemic stroke within 30 days of PCC4 administration.

RESULTS

In total, 14 patients received 17 administrations of PCC4. One patient received 3 administrations, and 1 other patient received 2 administrations during separate encounters. The median dose was 500 units or 6.6 units/kg (range = 4.2-14.1 units/kg). Of the PCC4 administrations, 82% (14/17) were for low bleed risk procedures and 76% (13/17) were for elective procedures. There were no cases of pump thrombosis, venous thromboembolism, or stroke within 30 days of the procedure.

CONCLUSIONS AND RELEVANCE

Low-dose PCC4 appears to be a safe and effective temporary reversal strategy for patients with LVADs undergoing low-bleed risk elective procedures.

Evaluation of anti-XA-guided versus APTT-guided management of intravenous unfractionated heparin in patients requiring a durable ventricular assist device

OBJECTIVE

The objective of this study was to compare the effectiveness and safety of anti-Xa-guided management versus aPTT-guided management of intravenous (IV) unfractionated heparin (UFH) in patients with a durable ventricular assist device (VAD).

MATERIALS AND METHODS

This was a retrospective study conducted at a single academic medical center. Patients were included if they had a durable VAD and were managed using aPTT-guided UFH management from May 2019 to May 2020 or were managed using anti-Xa-guided UFH management from May 2021 to December 2021. The primary outcome of the study was the median time to goal anticoagulation post-initiation of UFH. Secondary outcomes included the percentage of time within the therapeutic range and the incidence of thromboembolic and bleeding complications.

RESULTS

The study included 23 patients, 12 of whom were managed using anti-Xa-guided UFH, and 11 were managed using aPTT-guided UFH. The treatment arm using anti-Xa-guided UFH demonstrated a faster time to therapeutic anticoagulation goal range with a median time of 21.3 h [IQR = 12.2-34.8] compared to 37.3 h [IQR = 41-74] in the aPTT-guided UFH treatment arm (P = 0.03). In addition, the anti-Xa-guided UFH arm had a higher percentage of time within the therapeutic range, 76 % [IQR = 64.25-96.25] compared to 53 % [IQR = 41-74] in the aPTT-guided UFH arm (P = 0.04). Both arms had no significant differences in major bleeding events (P = 0.59) or clinically relevant minor bleeding events (P = 0.60) among patients. There was no incidence of thromboembolic events in either treatment arm.

CONCLUSION

Based on this single-center experience, anti-Xa-guided UFH management resulted in a faster time to therapeutic anticoagulation and a longer time within the desired therapeutic range. The results suggest that anti-Xa-guided monitoring may be superior to UFH-guided monitoring in patients with a durable VAD.

2024 AHA/ACC/ACS/ASNC/HRS/SCA/SCCT/SCMR/SVM Guideline for Perioperative Cardiovascular Management for Noncardiac Surgery: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2024 AHA/ACC/ACS/ASNC/HRS/SCA/SCCT/SCMR/SVM Guideline for Perioperative Cardiovascular Management for Noncardiac Surgery" provides recommendations to guide clinicians in the perioperative cardiovascular evaluation and management of adult patients undergoing noncardiac surgery.

METHODS

A comprehensive literature search was conducted from August 2022 to March 2023 to identify clinical studies, reviews, and other evidence conducted on human subjects that were published in English from MEDLINE (through PubMed), EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline.

STRUCTURE

Recommendations from the "2014 ACC/AHA Guideline on Perioperative Cardiovascular Evaluation and Management of Patients Undergoing Noncardiac Surgery" have been updated with new evidence consolidated to guide clinicians; clinicians should be advised this guideline supersedes the previously published 2014 guideline. In addition, evidence-based management strategies, including pharmacological therapies, perioperative monitoring, and devices, for cardiovascular disease and associated medical conditions, have been developed.

2024 AHA/ACC/ACS/ASNC/HRS/SCA/SCCT/SCMR/SVM Guideline for Perioperative Cardiovascular Management for Noncardiac Surgery: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2024 AHA/ACC/ACS/ASNC/HRS/SCA/SCCT/SCMR/SVM Guideline for Perioperative Cardiovascular Management for Noncardiac Surgery" provides recommendations to guide clinicians in the perioperative cardiovascular evaluation and management of adult patients undergoing noncardiac surgery.

METHODS

A comprehensive literature search was conducted from August 2022 to March 2023 to identify clinical studies, reviews, and other evidence conducted on human subjects that were published in English from MEDLINE (through PubMed), EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline.

STRUCTURE

Recommendations from the "2014 ACC/AHA Guideline on Perioperative Cardiovascular Evaluation and Management of Patients Undergoing Noncardiac Surgery" have been updated with new evidence consolidated to guide clinicians; clinicians should be advised this guideline supersedes the previously published 2014 guideline. In addition, evidence-based management strategies, including pharmacological therapies, perioperative monitoring, and devices, for cardiovascular disease and associated medical conditions, have been developed.

Right heart failure with left ventricular assist devices: Preoperative, perioperative and postoperative management strategies. A clinical consensus statement of the Heart Failure Association (HFA) of the ESC

Right heart failure (RHF) following implantation of a left ventricular assist device (LVAD) is a common and potentially serious condition with a wide spectrum of clinical presentations with an unfavourable effect on patient outcomes. Clinical scores that predict the occurrence of right ventricular (RV) failure have included multiple clinical, biochemical, imaging and haemodynamic parameters. However, unless the right ventricle is overtly dysfunctional with end-organ involvement, prediction of RHF post-LVAD implantation is, in most cases, difficult and inaccurate. For these reasons optimization of RV function in every patient is a reasonable practice aiming at preparing the right ventricle for a new and challenging haemodynamic environment after LVAD implantation. To this end, the institution of diuretics, inotropes and even temporary mechanical circulatory support may improve RV function, thereby preparing it for a better adaptation post-LVAD implantation. Furthermore, meticulous management of patients during the perioperative and immediate postoperative period should facilitate identification of RV failure refractory to medication. When RHF occurs late during chronic LVAD support, this is associated with worse long-term outcomes. Careful monitoring of RV function and characterization of the origination deficit should therefore continue throughout the patient's entire follow-up. Despite the useful information provided by the echocardiogram with respect to RV function, right heart catheterization frequently offers additional support for the assessment and optimization of RV function in LVAD-supported patients. In any patient candidate for LVAD therapy, evaluation and treatment of RV function and failure should be assessed in a multidimensional and multidisciplinary manner.

Drug therapy and catheter ablation for management of arrhythmias in continuous flow left ventricular assist device's patients: a Clinical Consensus Statement of the European Heart Rhythm Association and the Heart Failure Association of the ESC

Left ventricular assist devices (LVADs) are an increasingly used strategy for the management of patients with advanced heart failure. Although these devices effectively improve survival, atrial and ventricular arrhythmias are common with a prevalence of 20-50% at one year after LVAD implantation. Arrhythmias predispose these patients to additional risk and are associated with considerable morbidity from recurrent implantable cardioverter-defibrillator shocks, progressive failure of the unsupported right ventricle, and herald an increased risk of mortality. Management of patients with arrhythmias and LVAD differs in many aspects from the general population heart failure patients. These include ruling out the reversible causes of arrhythmias that in LVAD patients may include mechanical irritation from the inflow cannula and suction events. For patients with symptomatic arrhythmias refractory to medical treatment, catheter ablation might be relevant. There are specific technical and procedural challenges perceived to be unique to LVAD-related ventricular tachycardia (VT) ablation such as vascular and LV access, signal filtering, catheter manoeuvrability within decompressed chambers, and electroanatomic mapping system interference. In some patients, the arrhythmogenic substrate might not be readily accessible by catheter ablation after LVAD implantation. In this regard, the peri-implantation period offers a unique opportunity to surgically address arrhythmogenic substrate and suppress future VT recurrences. This document aims to address specific aspects of the management of arrhythmias in LVAD patients focusing on anti-arrhythmic drug therapy and ablations.

Venopulmonary extracorporeal membrane oxygenation for right ventricular support as a bridge to lung transplantation: A narrative review

This review evaluates the effectiveness of veno-pulmonary support with an oxygenator using extracorporeal membrane oxygenation as a bridge to lung transplantation strategy in patients undergoing veno-venous extracorporeal membrane oxygenation while awaiting lung transplantation. Examining indications, contraindications, and clinical outcomes, the study highlights potential benefits, drawing insights from successful cases in South Korea and the United States. Despite limited sample sizes, veno-pulmonary support with an oxygenator using extracorporeal membrane oxygenation emerges as a promising approach for further investigation in lung transplantation support. The review emphasizes its role in improving hemodynamic status, preventing complications during extended waiting periods, and presenting a cost-effective alternative to traditional methods, especially in developing countries. While in-hospital mortality rates range from 0% to 10%, comparable to other approaches, cautious optimism surrounds veno-pulmonary support with an oxygenator using extracorporeal membrane oxygenation, urging expanded research to solidify its standing in enhancing patient outcomes, reducing costs, and promoting transplant success.

SOPRANO: Macitentan in patients with pulmonary hypertension following left ventricular assist device implantation

Macitentan is a dual endothelin receptor antagonist (ERA) approved for treating pulmonary arterial hypertension (PAH). SOPRANO evaluated the efficacy and safety of macitentan versus placebo in pulmonary hypertension (PH) patients after left ventricular assist device (LVAD) implantation. SOPRANO was a phase 2, multicenter, double-blind, randomized, placebo-controlled, parallel-group study. Patients with an LVAD implanted within the prior 90 days who had persistent PH (i.e., mean pulmonary arterial pressure ≥25 mmHg, pulmonary artery wedge pressure [PAWP] ≤18 mmHg, and pulmonary vascular resistance [PVR] >3 Wood units [WU]) were randomized (1:1) to macitentan 10 mg or placebo once daily for 12 weeks. The primary endpoint was change in PVR. Secondary endpoints included change in right-heart catheterization hemodynamic variables, N-terminal prohormone of brain natriuretic peptide levels, World Health Organization functional class, and safety/tolerability. Fifty-seven patients were randomized to macitentan (n = 28) or placebo (n = 29). A statistically significant reduction in PVR from baseline to Week 12 was observed with macitentan versus placebo (placebo-corrected geometric mean ratio, 0.74; 95% confidence interval, 0.58-0.94; p = .0158). No statistically significant differences were observed in secondary endpoints. In a post-hoc analysis, 66.7% of patients receiving macitentan achieved PVR <3 WU versus 40.0% receiving placebo (p = .0383). Macitentan was generally well tolerated; adverse events were consistent with those in previous PAH studies with macitentan. In conclusion, macitentan showed promising tolerability and significantly reduced PVR in PH patients with persistently elevated PVR after LVAD implantation. ClinicalTrials. gov identifier: NCT02554903.

Fibrin clot permeability (Ks) in patients on left ventricular assist device

Patients on left ventricular assist devices (LVAD) are prone to excessive hemostasis disturbances due to permanent contact of artificial pump surfaces with blood components. We aimed to investigate if fibrin clot permeability is altered in patients on long-term continuous-flow LVAD therapy and if the clot permeability is associated with clinical characteristics and adverse events. We investigated 85 end-stage heart failure patients (90.6% men, age 48.6-63.8 years) scheduled for continuous flow long-term LVAD support according to current clinical indications. The patients were assessed periodically: prior to LVAD implantation (T1), 3-6 months (T2) after LVAD implantation, 6-12 months after (T3) and then every 6 months. We tested the first three blood samples (T1-T3) and the last available blood sample (T4), but no longer than 5 years after LVAD implantation. We assessed hemostasis parameters (Activated Partial Thromboplastin Time (APTT) Prothrombin Time, Activated Partial Thromboplastin Time, Fibrinogen, D-dimer, Antithrombin, Thrombin Time, Factor VIII, and von Willebrand Factor, aspirin-induced platelet inhibition, adenosine-diphosphate test) changes during the study period. Fibrin Clot Permeability was evaluated using a pressure system and Permeability Coefficient (Ks) was calculated. We observed a decrease in fibrin clot permeability (Ks) between T1, T2, T3 and T4 time periods; P < 0.01 for each comparison. Fibrin clot permeability was negatively correlated with fibrinogen concentration: r = - 0.51, P < 0.001, factor VIII activity r = - 0.42, P < 0.001. There was no association of Ks with age, Left Ventricular Ejection Fraction (LVEF) and medications P > 0.001, however cumulative measurements in patients on aspirin showed shortening of Ks in this group P = 0.0123. Major adverse cardiac and cerebrovascular events (MACCE) occurred in 36.5% patients, bleeding events in 25.9%, Net Adverse Clinical Events (NACE) in 62.4%; 31.7% patients died, and 17.6% underwent transplantation. The transplantation was considered as the endpoint. Discrepancies in Ks were observed between patients with MACCE, bleeding, and NACE, and patients without adverse events. Ks showed a constant trend towards normalization (P < 0.01) only in patients without adverse events. Patients with advanced heart failure have disturbed clot structure. A trend towards normalization of the Ks values is associated with fewer thromboembolic and bleeding complications in this group of patients.

Preemptive Impella 5.5 insertion to reduce operative risk in high-risk cardiac surgery: A case report

INTRODUCTION AND IMPORTANCE

Society of thoracic surgery (STS) risk score has been used as a tool to gauge operative risk of cardiac surgery patients. High-risk patients, with STS risk score > 8 %, are considered as having prohibitive risk and are not offered surgery. There is no established strategy to minimize postoperative hemodynamic instability using mechanical circulatory support (MCS), despite growing interest in utilizing MCS prior to hemodynamic instability. The Impella 5.5 can provide enough perfusion and unload the left ventricle.

CASE PRESENTATION

We managed a 75-year-old male with multiple comorbidities and a presumed Society of Thoracic Surgeons (STS) score higher than 9.8 %, who had redo coronary artery bypass grafting and aortic and mitral valve replacement with concomitant implantation of the Impella 5.5. Patient had a good recovery despite developing post-operative atrial fibrillation.

DISCUSSION

Impella is used as a mechanical circulatory support device in patients with cardiogenic shock. It provides forward flow and effectively unloads the left ventricle. The concomitant placement of the Impella 5.5 in high-risk cardiac candidates may be associated with reduced operative risk.

CONCLUSION

Placement of the device as part of surgical plan can potentially mitigate the perioperative risk by providing adequate endogean perfusion, decrease pressor support, unloading LV.

Perioperative interventions for the prevention of surgical wound infection in adult patients undergoing left ventricular assist devices implantation: A scoping review

BACKGROUND

Surgical wound infection is the most frequent type of care health associated infection. Lack of knowledge about the prevention of surgical wound infection in patients undergoing left ventricular assist device implantation could significantly undermine the potential benefits of surgical intervention.

OBJECTIVES

This study aimed to map the recommendations for adult patients undergoing left ventricular assist device implantation.

DESIGN

This is a scoping review, being registered in the Open Science Framework under DOI https://doi.org/10.17605/OSF.IO/Q76B3 (https://osf.io/q76b3/).

METHOD

Left ventricular assist device coordinators and nurse specialists in dermatology and stomatherapy conducted a scoping review in Scopus, The Cochrane Database of Systematic Reviews, Cumulative Index to Nursing and Allied Health Literature (CINAHL), limited to the period between 2015 and 2022. The results of this scoping review will be discussed and presented in separate articles. This paper will synthesize research evidence on the perioperative topic.

RESULTS

The initial searches resulted in 771 studies. Sixty nine met the eligibility criteria and were included in the scoping review. Eight articles addressing the perioperative topic that answered the question of this article were included.

CONCLUSION

Although this scoping review included heterogeneous, and scarce studies with left ventricular assist device patients. As such, there are many promising future research directions for this topic.

IMPLICATIONS FOR CLINICAL PRACTICE

Infection surveillance should be an integral part of left ventricular assist device implantation programs in health care institutions. Velvet completely buried in subcutaneous tissues reduces transmission system infection. Triple tunnel method reduces transmission system infection risk.

Evaluation of enoxaparin for bridging of warfarin in outpatients with left ventricular assist devices (LVADs)

BACKGROUND

Patients with left ventricular assist devices (LVADs) require systemic anticoagulation. The use of enoxaparin for bridging to warfarin remains understudied in this population.

METHODS

This single-center retrospective study was performed to characterize enoxaparin use and associated thrombotic and bleeding outcomes in adult outpatients with LVADs from January 2018 to July 2021.

RESULTS

Fifty-four enoxaparin bridging events were evaluated in 49 patients. Most patients with HeartMate II (HM2) and HeartWare (HVAD) devices received enoxaparin dosed 1 mg/kg every 12 h. In patients with HeartMate 3 (HM3) devices, an equal number of patients received 0.5 mg/kg every 12 h and 1 mg/kg every 12 h, with a smaller subset receiving intermediate doses. The median duration of bridging was 6 days (4-8 [IQR]). One major bleeding event required discontinuation of enoxaparin and hospitalization in a patient with an HM3 device. Thrombotic events occurred in four patients with two incidents of pump thrombosis requiring pump exchange and two ischemic strokes. All thrombotic events occurred in patients with HVAD or HM2 devices.

CONCLUSION

These results suggest that enoxaparin bridging in LVAD patients was well-tolerated with low bleeding and thrombotic rates, particularly with the HM3 device.

Clinical experience with medical hypnosis as an adjunctive therapy in heart surgery

Heart surgery patients are at high risk for psychological trauma and comorbid psychological disorders. Depression, anxiety, and post-traumatic stress disorders in this patient group are predictors of outcomes after cardiac surgery. Medical hypnosis is effective for non-pharmacologic prevention and treatment of psychological disorders and has been associated with improved health-related quality of life and better cardiovascular outcomes. This contribution makes note of evidence of the effectiveness of medical hypnosis in a discussion of the clinical experience with specific hypnotherapeutic tools and interventions from the perspective of the mental health team in one large cardiac center in Germany. Based on our experience, we encourage heart centers to educate their heart surgery care teams about the core concepts of medical hypnosis and to make hypnotherapeutic techniques available as an adjunctive therapy.

Left Ventricular Assist Device and the Current State of the Art: HeartMate 3 at 5 Years

Left ventricular assist devices (LVADs) or cardiac transplantation are the two prevailing methods of treating patients with end-stage heart failure. The availability of donor hearts is insufficient to meet the needs of patients with advanced heart failure. LVADs offer a potential alternative to transplantation for those patients who cannot wait or are otherwise unsuited for cardiac transplantation. The field has made tremendous progress in the past 20 years. In this review, the current state of the art is summarized with respect to current generation LVADs.

Comparing the Efficacy and Safety of Warfarin Monotherapy vs. Warfarin and Aspirin for Adult Patients With Left Ventricular Assist Devices: A Meta-Analysis

The aim of this meta-analysis was to assess the safety and efficacy of warfarin plus aspirin versus warfarin monotherapy in patients with left ventricular assist devices (LVAD). The present meta-analysis was conducted using the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Two authors systematically searched online databases, including PubMed, EMBASE, the Cochrane Library, and Web of Science from inception to December 31, 2023. Outcomes assessed in this meta-analysis included any thrombotic event, bleeding events, and all-cause mortality. A total of five articles were included in the meta-analysis, enrolling a pooled sample size of 876 patients, including 405 in the warfarin monotherapy group and 471 in the warfarin plus aspirin group. Pooled analysis showed that the risk of thrombotic events was not significantly different between the two groups (risk ratio (RR): 0.46, 95% confidence interval (CI): 0.15-1.37). The risk of bleeding events was significantly lower in patients receiving warfarin alone compared to patients receiving aspirin plus warfarin (RR: 0.67, 95% CI: 0.53-0.85). The risk of all-cause mortality was not significantly different between patients receiving warfarin alone and patients receiving aspirin plus warfarin (RR: 0.92, 95% CI: 0.65-1.30). Despite the potential benefits of discontinuing aspirin, the decision should be approached cautiously, considering the undefined risks of discontinuing anticoagulation in LVAD patients.

Induced Abortion for Maternal Cardiac Indication: 2 Cases of Unintended Pregnancy With LVAD

We present 2 cases of patients with left ventricular assist device who underwent an induced abortion in the first and second trimester, respectively. Comprehensive counseling is critical for this patient population, and close coordination of interdisciplinary teams is required in the setting of continuing pregnancy or medically indicated abortion.

Management of Heart Failure in Hospitalized Patients

Heart failure affects more than 6 million people in the United States, and hospitalizations for decompensated heart failure confer a heavy toll in morbidity, mortality, and health care costs. Clinical trials have demonstrated effective interventions; however, hospitalization and mortality rates remain high. Key components of effective hospital care include appropriate diagnostic evaluation, triage and risk stratification, early implementation of guideline-directed medical therapy, adequate diuresis, and appropriate discharge planning.

Cardiological Challenges Related to Long-Term Mechanical Circulatory Support for Advanced Heart Failure in Patients with Chronic Non-Ischemic Cardiomyopathy

Long-term mechanical circulatory support by a left ventricular assist device (LVAD), with or without an additional temporary or long-term right ventricular (RV) support, is a life-saving therapy for advanced heart failure (HF) refractory to pharmacological treatment, as well as for both device and surgical optimization therapies. In patients with chronic non-ischemic cardiomyopathy (NICM), timely prediction of HF's transition into its end stage, necessitating life-saving heart transplantation or long-term VAD support (as a bridge-to-transplantation or destination therapy), remains particularly challenging, given the wide range of possible etiologies, pathophysiological features, and clinical presentations of NICM. Decision-making between the necessity of an LVAD or a biventricular assist device (BVAD) is crucial because both unnecessary use of a BVAD and irreversible right ventricular (RV) failure after LVAD implantation can seriously impair patient outcomes. The pre-operative or, at the latest, intraoperative prediction of RV function after LVAD implantation is reliably possible, but necessitates integrative evaluations of many different echocardiographic, hemodynamic, clinical, and laboratory parameters. VADs create favorable conditions for the reversal of structural and functional cardiac alterations not only in acute forms of HF, but also in chronic HF. Although full cardiac recovery is rather unusual in VAD recipients with pre-implant chronic HF, the search for myocardial reverse remodelling and functional improvement is worthwhile because, for sufficiently recovered patients, weaning from VADs has proved to be feasible and capable of providing survival benefits and better quality of life even if recovery remains incomplete. This review article aimed to provide an updated theoretical and practical background for those engaged in this highly demanding and still current topic due to the continuous technical progress in the optimization of long-term VADs, as well as due to the new challenges which have emerged in conjunction with the proof of a possible myocardial recovery during long-term ventricular support up to levels which allow successful device explantation.

Durable Mechanical Circulatory Support: JACC Scientific Statement

Despite advances in medical therapy for patients with stage C heart failure (HF), survival for patients with advanced HF is <20% at 5 years. Durable left ventricular assist device (dLVAD) support is an important treatment option for patients with advanced HF. Innovations in dLVAD technology have reduced the risk of several adverse events, including pump thrombosis, stroke, and bleeding. Average patient survival is now similar to that of heart transplantation at 2 years, with 5-year dLVAD survival now approaching 60%. Unfortunately, greater adoption of dLVAD therapy has not been realized due to delayed referral of patients to advanced HF centers, insufficient clinician knowledge of contemporary dLVAD outcomes (including gains in quality of life), and deprioritization of patients with dLVAD support waiting for heart transplantation. Despite these challenges, novel devices are on the horizon of clinical investigation, offering smaller size, permitting less invasive surgical implantation, and eliminating the percutaneous lead for power supply.

Transdermal wires for improved integration in vivo

Alternative engineering approaches have led the design of implants with controlled physical features to minimize adverse effects in biological tissues. Similar efforts have focused on optimizing the design features of percutaneous VAD drivelines with the aim to prevent infection, omitting however a thorough look on the implant-skin interactions that govern local tissue reactions. Here, we utilized an integrated approach for the biophysical modification of transdermal implants and their evaluation by chronic sheep implantation in comparison to the standard of care VAD drivelines. We developed a novel method for the transfer of breath topographical features on thin wires with modular size. We examined the impact of implant's diameter, surface topography, and chemistry on macroscopic, histological, and physical markers of inflammation, fibrosis, and mechanical adhesion. All implants demonstrated infection-free performance. The fibrotic response was enhanced by the increasing diameter of implants but not influenced by their surface properties. The implants of small diameter promoted mild inflammatory responses with improved mechanical adhesion and restricted epidermal downgrowth, in both silicone and polyurethane coated transdermal wires. On the contrary, the VAD drivelines with larger diameter triggered severe inflammatory reactions with frequent epidermal downgrowth. We validated these effects by quantifying the infiltration of macrophages and the level of vascularization in the fibrotic zone, highlighting the critical role of size reduction for the benign integration of transdermal implants with skin. This insight on how the biophysical properties of implants impact local tissue reactions could enable new solutions on the transdermal transmission of power, signal, and mass in a broad range of medical devices.

Gastrointestinal bleeding in patients with continuous-flow left ventricular assist devices: A comprehensive review

BACKGROUND

Gastrointestinal bleeding is a major cause of morbidity that plagues the quality of life of patients supported on contemporary continuous-flow left ventricular assist devices (CF-LVADs). Despite benefits in survival and the nearly 50% reduction in complications provided by CF-LVADs, bleeding remains one of the most frequent adverse events with CF-LVAD implants. The CF-LVADs cause an increased risk of bleeding mainly due to the activation of the coagulation cascade.

METHODS

A literature search was done using PubMed and Google Scholar from Inception to February 2022. Qualitative analyses of the articles retrieved were used to construct this review. This review attempts to provide a comprehensive summary of the epidemiology, pathophysiology, risk stratification, and management of gastrointestinal bleeding as a complication of CF-LVAD as well as propose an algorithm for diagnosis and treatment.

RESULTS

Bleeding can occur at different sites in the gastrointestinal tract, the most common underlying pathology being arteriovenous malformations located in the upper gastrointestinal tract The increased prevalence of gastrointestinal (GI) bleeding in CF-LVAD patients has been attributed to the physiology of the LVAD itself, the use of anticoagulants, as well as patient comorbidities. Management involves pharmacologic and nonpharmacologic strategies.

CONCLUSIONS

CF-LVAD-supported patients have a significant risk of GI bleeding that is mainly caused by arteriovenous malformations located in the upper GI tract. The increased prevalence of GI bleeding in CF-LVAD patients is attributed to several etiologies that include factors attributed to the device itself and extrinsic factors such as the use of anticoagulation.

Transition to heart transplantation in post-myocardial infarction ventricular septal rupture: a systematic review

Post-myocardial infarction ventricular septal rupture (MI-VSR) remains a dreadful complication with dismal prognosis. Surgical repair is the primary treatment strategy, whereas the role of heart transplantation (HT) as a primary option in MI-VSR is limited to case reports (CRs). We performed a systematic review of CRs to describe in-hospital mortality, and survival at 6 and 12 months in adult patients with MI-VSR treated with HT as a primary or bailout strategy. We performed a comprehensive search of Web of Science, PubMed, and Ovid Medline. The last search was completed on March 10, 2020. An aggregated score based on the CARE case report guideline was used to assess the quality of the CRs. We included CRs that described adult patients with MI-VSR treated with HT as a primary or bailout strategy. A total of 14 CRs between 1994 and 2015 were included, retrieving and analyzing the characteristics of 17 patients. A total of 12 patients underwent HT, with HT being the primary strategy in 8 patients and a bailout strategy for 4 patients following initial surgical repair, while 5 patients died awaiting HT under mechanical circulatory support (MCS), accounting for the total in-hospital mortality of this series (29%). Regarding long-term outcomes, 6 patients were reported to be alive at 6 months and 1 year after HT, while information was missing in the remaining 6 patients. In conclusion, HT supported by the use of temporary and durable MCS as a bridge to HT could be a feasible primary or bailout strategy to reduce the high in-hospital mortality of patients with MI-VSR.

Left Ventricular Assist Devices: A Primer For the General Cardiologist

Durable implantable left ventricular assist devices (LVADs) have been shown to improve survival and quality of life for patients with stage D heart failure. Even though LVADs remain underused overall, the number of patients with heart failure supported with LVADs is steadily increasing. Therefore, general cardiologists will increasingly encounter these patients. In this review, we provide an overview of the field of durable LVADs. We discuss which patients should be referred for consideration of advanced heart failure therapies. We summarize the basic principles of LVAD care, including medical and surgical considerations. We also discuss the common complications associated with LVAD therapy, including bleeding, infections, thrombotic issues, and neurologic events. Our goal is to provide a primer for the general cardiologist in the recognition of patients who could benefit from LVADs and in the principles of managing patients with LVAD. Our hope is to "demystify" LVADs for the general cardiologist.

Concomitant or late aortic valve intervention and its efficacy for aortic insufficiency associated with continuous-flow left ventricular assist device implantation

Moderate to severe aortic insufficiency (AI) in patients who underwent continuous-flow left ventricular assist device (CF-LVAD) implantation is a significant complication. According to the INTERMACS registry analysis, at least mild AI occurs in 55% of patients at 6 months after CF-LVAD implantation and moderate to severe AI is significantly associated with higher rates of re-hospitalization and mortality. The clinical implications of these data may underscore consideration of prophylactic aortic valve replacement, or repair, at the time of CF-LVAD implantation, particularly with expected longer duration of support and in patients with preexisting AI that is more than mild. More crucially, even if a native aortic valve is seemingly competent at the time of VAD implantation, we frequently find de novo AI as time goes by, potentially due to commissural fusion in the setting of inconsistent aortic valve opening or persistent valve closure caused by CF-LVAD support, that alters morphological and functional properties of innately competent aortic valves. Therefore, close monitoring of AI is mandatory, as the prognostic nature of its longitudinal progression is still unclear. Clearly, significant AI during VAD support warrants surgical intervention at the appropriate timing, especially in patients of destination therapy. Nonetheless, such an uncertainty in the progression of AI translates to a lack of consensus regarding the management of this untoward complication. In practice, proposed surgical options are aortic valve replacement, repair, closure, and more recently transcatheter aortic valve implantation or closure. Transcatheter approach is of course less invasive, however, its efficacy in terms of long-term outcome is limited. In this review, we summarize the recent evidence related to the pathophysiology and surgical treatment of AI associated with CF-LVAD implantation.

Antithrombotic therapy for durable left ventricular assist devices - current strategies and future directions

Left ventricular assist devices (LVADs) improve survival and quality of life for patients with advanced heart failure but are associated with high rates of thromboembolic and hemorrhagic complications. Antithrombotic therapy is required following LVAD implantation, though practices vary. Identifying a therapeutic strategy that minimizes the risks of thromboembolic and hemorrhagic complications is critical to optimizing patient outcomes and is an area of active investigation. This paper reviews strategies for initiating and maintaining antithrombotic therapy in durable LVAD recipients, focusing on those with centrifugal-flow devices.

Bridge to nowhere: A retrospective single-center study on patients using chronic intravenous inotropic support as bridge therapy who do not receive surgical therapy

Background

Many patients with advanced heart failure (HF) are administered chronic intravenous inotropic support (CIIS) as bridge to surgical therapy; some ultimately never receive surgery. We aimed to describe reasons patients “crossover” from CIIS as bridge therapy to palliative therapy, and compare end-of-life outcomes to patients initiated on CIIS as palliative therapy.

Methods

Single-institution, retrospective cohort study of patients on CIIS as bridge or palliative therapy between 2010 and 2016; data obtained through review of health records and multi-disciplinary selection meeting minutes, was analyzed using descriptive and inferential statistics.

Results

Of 246 patients discharged on CIIS as bridge therapy, 37 (16%) (male n = 28, 76%; African American n = 22, 60%) ultimately never received surgery. 67 matched patients on CIIS as palliative therapy were included for analysis (male n = 47, 70%; African American n = 47, 70%). The most common reasons for “crossover” from CIIS as bridge therapy to palliative therapy were frailty (n = 10, 27%), cardiac arrest (n = 5, 13.5%), and progressive non-cardiac illnesses (n = 6, 16.2%). A similar percentage of patients in the bridge (n = 28, 76%) and palliative (n = 48, 72%) groups died outside the hospital (P=0.66); however, fewer bridge patients received hospice care compared to the palliative group (35% vs 69%, P < 0.001). Comparing patients who died in the hospital, bridge patients (n = 9; 100%) were more likely to die in the intensive care unit than palliative patients (n = 8; 42%) (P < 0.001).

Conclusion

Patients on CIIS as bridge therapy who do not ultimately receive surgical therapy “crossover” to palliative intention due to frailty, or development of or identification of serious illnesses. Nevertheless, these “bridge to nowhere” patients are less likely to receive palliative care or hospice and more likely to die in the intensive care unit than patients on CIIS as palliative therapy.

Percutaneous Decommissioning of a Left Ventricular Assist Device in a Patient With Myocardial Recovery

A 37-year-old man was referred for consideration of percutaneous decommissioning of a left ventricular assist device (LVAD). Following careful hemodynamic monitoring during pump turn-down and temporary outflow graft occlusion, the LVAD was permanently decommissioned by using a vascular plug to induce thrombosis of the outflow graft. (Level of Difficulty: Advanced.)

Ex-Vivo Preservation with the Organ Care System in High Risk Heart Transplantation

Objective: Ex vivo organ perfusion is an advanced preservation technique that allows graft assessment and extended ex situ intervals. We hypothesized that its properties might be especially beneficial for high-risk recipients and/or donors with extended criteria. Methods: We reviewed the outcomes of 119 consecutive heart transplant patients, which were divided into two groups: A (OCS) vs. B (conventional). Ex vivo organ perfusion was performed using the Organ Care System (OCS). Indications for OCS-usage were expected ischemic time of >4 h or >2 h plus given extended donor criteria. Results: Both groups included mostly redo cases (A: 89.7% vs. B: 78.4%; p = 0.121). Incidences of donors with previous cardiac arrest (%) (A: 32.4 vs. B: 22.2; p < 0.05) or LV-hypertrophy (%) (A: 19.1 vs. B: 8.3; p = 0.119) were also increased in Group A. Ex situ time (min) was significantly longer in Group A (A: 381 (74) vs. B: 228 (43); p < 0.05). Ventilation time (days) (A: 10.0 (19.9) vs. B: 24.3 (43.2); p = 0.057), postoperative need for ECLS (%) (A: 25.0 vs. B: 39.2; p = 0.112) and postoperative dialysis (chronic) (%) (A: 4.4 vs. B: 27.5; p < 0.001) were numerically better in the OCS group, without any difference in the occurrence of early graft rejection. The 30-d-survival (A: 92.4% vs. B: 90.2%; p = 0.745) and mid-term survival were statistically not different between both groups. Conclusions: OCS heart allowed safe transplantation of surgically complex recipients with excellent one-year outcomes, despite long preservation times and unfavourable donor characteristics. Furthermore, we observed trends towards decreased ventilation times and fewer ECLS treatments. In times of reduced organ availability and increasing recipient complexity, OCS heart is a valuable instrument that enables otherwise infeasible allocations and contributes to increase surgical safety.

Heart, kidney and left ventricular assist device: a complex trio

BACKGROUND

Heart failure (HF) is a complex syndrome affecting the whole body, kidneys included. The left ventricular assist device (LVAD) is a valid option for patients with very severe HF. Focusing on renal function, LVAD implantation could theoretically reverse the detrimental effects of HF syndrome on kidneys. However, implanting an LVAD is a high-risk surgical procedure, and LVAD patients have higher risk of bleeding, device thrombosis, strokes, renal impairment, multi-organ failure and infections. Furthermore, an LVAD has its own particular effects on the renal system.

METHODS

In this review, we provide a comprehensive overview of the complex interaction between LVAD and the kidneys from the pathophysiological and clinical perspectives. An analysis of the different effects of pulsatile-flow and continuous-flow LVAD is provided.

RESULTS

Despite their limitations, creatinine-based estimated glomerular filtration rate (eGFR) formulas help to stratify patients by their post-LVAD placement prognosis. Poor basal renal function, the onset of acute kidney injury or the need for renal replacement therapy after LVAD implantation negatively influences a patient's prognosis. LVAD can also prompt an improvement in renal function, however, with some counterintuitive effects on a patient's prognosis.

CONCLUSION

It is still hard to say whether different trends in eGFR depend on different renal conditions before LVAD placement, on a patient's better overall status or on a particular patient management strategy before and/or after the device's implantation. Steps should be taken to solve this question because finding the best candidates for LVAD implantation is of paramount importance to ensure the best outcomes.

Short-term mechanical circulatory support in elderly patients

BACKGROUND

Age over 70 years seems to confer poor prognosis for patients under mechanical circulatory support (MCS). Advanced age is usually a relative contraindication. Our objective was to assess the impact of age on survival of patients with short-term MCS.

METHODS

Retrospective analysis of ≥70-year-old patients supported with veno-arterial extracorporeal membrane oxygenation (VA-ECMO) or Impella CP® due to cardiogenic shock and other situations of hemodynamic instability in a referral hospital (elderly group), compared with younger patients (<70 years). We analyze factors associated with survival in elderly group.

RESULTS

Out of 164 short-term MCS implants from 2013 to October 2020, 45 (27.4%) correspond to ≥70-year-old patients (73.3% VA-ECMO; 26.7% Impella CP®), 80% as bridge to recovery and 15.6% for high-risk percutaneous coronary intervention (PCI). We found no significant differences in complications developed between both groups. Survivals at discharge (40% vs. 43.7%, p = 0.403) and at follow-up (median 13.6 [30] months) were similar in elderly and young patients (35.6% vs. 37.8%, log-rank p = 0.061). Predictive factors of mortality in elderly patients were peripheral artery disease (p = 0.037), higher lactate (p = 0.003) and creatinine (p = 0.035) at implant, longer cardiac arrest (p = 0.003), and worse post-implantation left ventricular ejection fraction (p = 0.003). Patients with indication of MCS for high-risk PCI had higher survival compared to other indications (p = 0.013).

CONCLUSION

Short-term MCS with VA-ECMO or Impella CP® in elderly patients may be a reasonable option in hemodynamic compromise situations as bridge to recovery or elective high-risk PCI, without a significant increase in complications or mortality. Age should not be an absolute contraindication, but careful selection of candidate patients is necessary.

Biotrauma during ultra-low tidal volume ventilation and venoarterial extracorporeal membrane oxygenation in cardiogenic shock: a randomized crossover clinical trial

Background

Cardiogenic pulmonary oedema (CPE) may contribute to ventilator-associated lung injury (VALI) in patients with cardiogenic shock. The appropriate ventilatory strategy remains unclear. We aimed to evaluate the impact of ultra-low tidal volume ventilation with tidal volume of 3 ml/kg predicted body weight (PBW) in patients with CPE and veno–arterial extracorporeal membrane oxygenation (V–A ECMO) on lung inflammation compared to conventional ventilation.

Methods

A single-centre randomized crossover trial was performed in the Cardiac Intensive Care Unit (ICU) at a tertiary university hospital. Seventeen adults requiring V–A ECMO and mechanical ventilation due to cardiogenic shock were included from February 2017 to December 2018. Patients were ventilated for two consecutive periods of 24 h with tidal volumes of 6 and 3 ml/kg of PBW, respectively, applied in random order. Primary outcome was the change in proinflammatory mediators in bronchoalveolar lavage fluid (BALF) between both ventilatory strategies.

Results

Ventilation with 3 ml/kg PBW yielded lower driving pressures and end-expiratory lung volumes. Overall, there were no differences in BALF cytokines. Post hoc analyses revealed that patients with high baseline levels of IL-6 showed statistically significant lower levels of IL-6 and IL-8 during ultra-low tidal volume ventilation. This reduction was significantly proportional to the decrease in driving pressure. In contrast, those with lower IL-6 baseline levels showed a significant increase in these biomarkers.

Conclusions

Ultra-low tidal volume ventilation in patients with CPE and V–A ECMO may attenuate inflammation in selected cases. VALI may be driven by an interaction between the individual proinflammatory profile and the mechanical load overimposed by the ventilator.

Trial registration The trial was registered in ClinicalTrials.gov (identifier NCT03041428, Registration date: 2nd February 2017).

Supplementary Information

The online version contains supplementary material available at 10.1186/s13613-021-00919-0.

Clinical findings associated with incomplete hemodynamic left ventricular unloading in patients with a left ventricular assist device

INTRODUCTION AND OBJECTIVES

The effect of a centrifugal continuous-flow left ventricular assist device (cfLVAD) on hemodynamic left ventricular unloading (HLVU) and the clinical conditions that interfere with hemodynamic optimization are not well defined.

METHODS

We retrospectively evaluated the likelihood of incomplete HLVU, defined as high pulmonary capillary wedge pressure (hPCWP)> 15mmHg in 104 ambulatory cfLVAD patients when the current standard recommendations for cfLVAD rotor speed setting were applied. We also evaluated the ability of clinical, hemodynamic and echocardiographic variables to predict hPCWP in ambulatory cfLVAD patients.

RESULTS

Twenty-eight percent of the patients showed hPCWP. The variables associated with a higher risk of hPCWP were age, central venous pressure, absence of treatment with renin-angiotensin-aldosterone system inhibitors, and brain natriuretic peptide levels. Patients with optimal HLVU had a 15.2±14.7% decrease in postoperative indexed left ventricular end-diastolic diameter compared with 8.9±11.8% in the group with hPCWP (P=.041). Independent predictors of hPCWP included brain natriuretic peptide and age. Brain natriuretic peptide <300 pg/mL predicted freedom from hPCWP with a negative predictive value of 86% (P <.0001).

CONCLUSIONS

An optimal HLVU can be achieved in up to 72% of the ambulatory cfLVAD patients when the current standard recommendations for rotor speed setting are applied. Age, central venous pressure and therapy with renin-angiotensin-aldosteron system inhibitors had a substantial effect on achieving this goal. Brain natriuretic peptide levels and the magnitude of reverse left ventricular remodeling seem to be useful noninvasive tools to evaluate HLVU in patients with functioning cfLVAD.

Outcomes of Orthotopic Heart Transplantation in the Setting of Acute Kidney Injury and Renal Replacement Therapy

OBJECTIVE

Heart transplantation in the setting of renal insufficiency is controversial. The objective of this study was to perform a descriptive analysis of patients who underwent orthotopic heart transplantation and renal replacement therapy (RRT) due to acute kidney injury (AKI).

DESIGN

An observational cohort study with retrospective data collection.

SETTING

A tertiary care hospital.

PARTICIPANTS

Fifty-one patients underwent orthotopic heart transplantation with cardiogenic shock under inotrope dependence, with nine patients having preoperative RRT and 42 patients not having preoperative RRT.

INTERVENTIONS

There were no interventions.

MEASUREMENTS AND MAIN RESULTS

Hospital mortality occurred in eight (15.6%) patients. Although there were no significant differences between the study groups (preoperative RRT 33.3% v controls 11.9%, p = 0.1), this study was underpowered to detect differences in mortality. Dialysis also was required in 52.4% of patients who were not on preoperative RRT. All survivors had full recovery of kidney function with similar timing after transplant (18.5 days v 15 days, p = 0.75). Actuarial survival was 82.4%, 76.5%, and 66.5% at six months, one year, and five years, respectively. A cold ischemic time greater than 180 minutes (hazard ratio [HR] 4.37 95% confidence interval [CI] 1.51-12.6; p = 0.006) and pretransplant RRT (HR = 7.19 95% CI 1.13-45.7; p = 0.04) were independent predictors of long-term mortality.

CONCLUSIONS

In a health system with limited funding and availability of mechanical circulatory support, heart transplantation in the setting of AKI, RRT, and low Interagency Registry for Mechanically Assisted Circulatory Support profile was associated with important hospital mortality. Among hospital survivors, however, all patients had full renal recovery and by 25 months there was no difference in mortality between those who required preoperative RRT and those who did not.

An ethical analysis of obesity as a determinant of pediatric heart transplant candidacy

BACKGROUND

Inclusion of BMI as criterion in the determination of heart transplant candidacy in children is a clinical and ethical challenge. Childhood obesity is increasing and children with heart disease are not spared. Currently, many adult heart transplant centers consider class II obesity and higher (BMI > 35 kg/m² ) to be a relative contraindication for transplantation due to risk of poor outcome after transplant. No national guidelines exist regarding consideration of BMI in pediatric heart transplant and outcomes data are limited. This leaves decisions about transplant candidacy in obese pediatric patients to individual institutions or on a case-by-case basis, allowing for bias and inequity.

METHODS

We review (a) the prevalence of childhood obesity, including among heart transplant candidates, (b) the lack of existing BMI guidelines, and (c) relevant literature on BMI and pediatric heart transplant outcomes. We discuss the ethical considerations of using obesity as a criterion using the principles of utility, justice, and respect for persons.

RESULTS

Existing transplant outcomes data do not show that obese children have different or poor enough outcomes compared to non-obese children to warrant exclusion. Moreover, obesity in the United States is unequally distributed by race and socioeconomic status. Children already suffering from health disparities are therefore doubly penalized if obesity denies them access to life-saving transplant.

CONCLUSION

Insufficient data exist to support using any BMI cutoff as an absolute contraindication for heart transplant in children. Attention should be paid to health equity issues when considering excluding a patient for transplant based on obesity.

Anticoagulation in Critically Ill Adults during Extracorporeal Circulation

Extracorporeal circuits including renal replacement therapy, extracorporeal membrane oxygenation, and ventricular assist devices are increasingly used in critically ill patients. The need for anticoagulation to provide circuit patency and avoid thrombosis remains a challenging task for treating physicians. In the presence of overall low scientific evidence concerning the optimal anticoagulants, monitoring tests, and therapeutic target ranges, recommendations are largely expert opinions and most centers use individual "in-house" anticoagulation protocols. This review gives a practical view on current concepts of anticoagulation strategies in patients with extracorporeal assist devices.

Pulmonary vasodilator use in continuous-flow left ventricular assist device management

Pulmonary hypertension (PH) due to left heart disease is the most common etiology for PH. PH in patients with heart failure with reduced fraction (HFrEF) is associated with reduced functional capacity and increased mortality. PH-HFrEF can be isolated post-capillary or combined pre- and post-capillary PH. Chronic elevation of left-sided filling pressures may lead to reverse remodeling of the pulmonary vasculature with development of precapillary component of PH. Untreated PH in patients with HFrEF results in predominant right heart failure (RHF) with irreversible end-organ dysfunction. Management of PH-HFrEF includes diuretics, vasodilators like angiotensin-converting enzyme inhibitors or angiotensin-receptor blockers or angiotensin-receptor blocker-neprilysin inhibitors, hydralazine and nitrates. There is no role for pulmonary vasodilator use in patients with PH-HFrEF due to increased mortality in clinical trials. In patients with end-stage HFrEF and fixed PH unresponsive to vasodilator challenge, implantation of continuous-flow left ventricular assist device (cfLVAD) results in marked improvement in pulmonary artery pressures within 6 months due to left ventricular (LV) mechanical unloading. The role of pulmonary vasodilators in management of precapillary component of PH after cfLVAD is not well-defined. The purpose of this review is to discuss the pharmacologic management of PH after cfLVAD implantation.

Antiplatelet and anticoagulation strategies for left ventricular assist devices

Left ventricular assist devices (LVAD) have revolutionized the management of advanced heart failure. However, complications rates remain high, among which hemorrhagic and thrombotic complications are the most important. Antiplatelet and anticoagulation strategies form a cornerstone of LVAD management and may directly affect LVAD complications. Concurrently, LVAD complications influence anticoagulation and anticoagulation management. A thorough understanding of device, patient, and management, including anticoagulation and antiplatelet therapies, are important in optimizing LVAD outcomes. This article provides a comprehensive state of the art review of issues related to antiplatelet and anticoagulation management in LVADs. We start with a historical overview, the epidemiology and pathophysiology of bleeding and thrombotic complications in LVADs. We then discuss platelet and anticoagulation biology followed by considerations prior to, during, and after LVAD implantation. This is followed by discussion of anticoagulation and the management of thrombotic and hemorrhagic complications. Specific problems, including management of heparin-induced thrombocytopenia, anticoagulant reversal, novel oral anticoagulants, artificial heart valves, and noncardiac surgeries are covered in detail.

Acute Kidney Injury After Heart Transplant: The Importance of Pulmonary Hypertension

OBJECTIVE

To determine whether relative pulmonary hypertension (PH), defined as the ratio of mean arterial pressure to mean pulmonary artery pressure, is associated with severe acute kidney injury (AKI) after heart transplant (HT).

DESIGN

An institutional review board-approved retrospective observational study.

SETTING

Tertiary care university hospital.

PARTICIPANTS

A total of 184 consecutive adult patients who underwent HT between January 2009 and December 2017 were included, and were followed up through December 2019. Using the Kidney Disease: Improving Global Outcomes classification, recipients were categorized into two groups: patients who developed stage 3 AKI (severe AKI) and those with minor or without AKI (nonsevere AKI) within seven days after transplant.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of the included patients, 83.2% developed AKI, in whom 40.8%, 19.6%, and 22.8% were stage 1, 2, and 3, respectively. With use of the multivariate logistic regression analysis, independent risk factors for stage 3 AKI post-HT included preoperative relative PH (odds ratio [OR]: 1.62, 95% confidence interval [95% CI]: 1.05-2.49, p = 0.028), central venous-to-pulmonary capillary wedge pressure ratio ≥0.86 (OR: 3.59, 95% CI: 1.13-11.43, p = 0.030), and postoperative right ventricular dysfunction (OR: 3.63, 95% CI: 1.50-8.75, p = 0.004). Conversely, preoperative estimated glomerular filtration rate (OR: 0.99, 95% CI: 0.97-1.00, p = 0.143) was not related to the development of stage 3 AKI post-HT.

CONCLUSIONS

Preoperative relative PH, central venous-to-pulmonary capillary wedge pressure ratio, and postoperative right ventricular failure by echocardiographic assessment were associated with severe AKI post-HT.