Predictors of Systolic Heart Failure and Mortality Following Orthotopic Liver Transplantation: a Single-Center Cohort

Hepatic ischemia-reperfusion syndrome and its effect on the cardiovascular system: The role of treprostinil, a synthetic prostacyclin analog

Hepatic ischemia-reperfusion syndrome has been the subject of intensive study and experimentation in recent decades since it is responsible for the outcome of several clinical entities, such as major hepatic resections and liver transplantation. In addition to the organ's post reperfusion injury, this syndrome appears to play a central role in the dysfunction of distant tissues and systems. Thus, continuous research should be directed toward finding effective therapeutic options to improve the outcome and reduce the postoperative morbidity and mortality rates. Treprostinil is a synthetic analog of prostaglandin I2, and its experimental administration has shown encouraging results. It has already been approved by the Food and Drug Administration in the United States for pulmonary arterial hypertension and has been used in liver transplantation, where preliminary encouraging results showed its safety and feasibility by using continuous intravenous administration at a dose of 5 ng/kg/min. Treprostinil improves renal and hepatic function, diminishes hepatic oxidative stress and lipid peroxidation, reduces hepatictoll-like receptor 9 and inflammation, inhibits hepatic apoptosis and restores hepatic adenosine triphosphate (ATP) levels and ATP synthases, which is necessary for functional maintenance of mitochondria. Treprostinil exhibits vasodilatory properties and antiplatelet activity and regulates proinflammatory cytokines; therefore, it can potentially minimize ischemia-reperfusion injury. Additionally, it may have beneficial effects on cardiovascular parameters, and much current research interest is concentrated on this compound.

Characteristics, Risk Factors, and Outcome of New-onset Systolic Heart Failure After Liver Transplantation: A Single-center Cohort

New-onset systolic heart failure (HF) after liver transplantation (LT) is a significant cause of morbidity and mortality; however, its characteristics are still insufficiently delineated. HF may involve the left ventricle (LV), right ventricle (RV), or both ventricles. We explored the incidence, characteristics, etiologies, risks, involved cardiac chambers, and outcomes of HF after LT.

Methods

This study included 528 adult patients with preoperative LV ejection fraction ≥ 55% who underwent LT between 2016 and 2020. The primary outcome was new-onset systolic HF, defined by the presence of clinical signs, symptoms, and echocardiographic evidence of reduced LVejection fraction <50% and RV dysfunction within the first year after LT.

Results

Thirty-one patients (6%) developed systolic HF within a median of 9 d (1-364). Of those, 23% of patients had ischemic HF, whereas 77% had nonischemic HF. Nonischemic HF was caused by stress (11), sepsis (8), or other factors (5). Nonischemic HF was secondary to isolated LV failure in 58% of patients or RV ± LV failure in 42% of patients. Recursive partitioning identified subgroups with varying risks and uncovered interaction between variables. HF risk increased from 4.2% to 13% when epinephrine and/or norepinephrine drips were used intraoperatively (P < 0.01). When no epinephrine and/or norepinephrine were used, HF risk increased from 3.1% to 38.5% if baseline hemoglobin was <7.2 g/dL (P < 0.01). When baseline hemoglobin was ≥7.2 g/dL, HF risk increased from 0% to 5.2% when ≥3500 mL crystalloid was used intraoperatively (P < 0.01). Posttransplant first-year survival and reversibility of HF depended on the etiology (stress, sepsis, ischemia, etc) and cardiac chamber involvement (isolated LV or RV ± LV). RV dysfunction was associated with inferior recovery of cardiac function and poorer survival than nonischemic isolated LV dysfunction (50% versus 70%, respectively).

Conclusions

Posttransplant new-onset HF is mostly nonischemic in nature and is associated with increased morbidity and mortality.

Incidence, predictors and outcomes of new onset systolic heart failure following Orthotopic liver transplant: A systematic review

BACKGROUND

New onset Systolic heart failure (SHF), characterized by new onset left ventricular (LV) systolic dysfunction with a reduction in ejection fraction (EF) of <40%, is a common cause of morbidity and mortality among Orthotopic liver transplant (OLT) recipients. Therefore, we aimed to evaluate the prevalence, the pre-transplant predictors, and the prognostic impact of SHF post-OLT.

METHODS

We conducted a systematic review of the literature using electronic databases MEDLINE, Web of Science, and Embase for studies reporting acute systolic heart failure post-liver transplant from inception to August 2021.

RESULT

Of 2604 studies, 13 met the inclusion criteria and were included in the final systematic review. The incidence of new-onset SHF post OLT ranged from 1.2% to 14%. Race, sex, or body mass index did not significantly impact the post-OLT SHF incidence. Alcoholic liver cirrhosis, pre-transplant systolic or diastolic dysfunction, troponin, brain natriuretic peptide (BNP), blood urea nitrogen (BUN) elevation, and hyponatremia were noted to be significantly associated with the development of SHF post-OLT. The significance of MELD score in the development of post-OLT SHF is controversial. Pre-transplant beta-blocker and post-transplant tacrolimus use were associated with a lower risk of developing SHF. The average 1-year mortality rate in patients with SHF post-OLT ranged from 0.00% to 35.2%.

CONCLUSION

Despite low incidence, SHF post-OLT can lead to higher mortality. Further studies are required to fully understand the underlying mechanism and risk factors.

Evaluating Social Determinants of Health Variables in Advanced Analytic and Artificial Intelligence Models for Cardiovascular Disease Risk and Outcomes: A Targeted Review

Introduction/Purpose

Predictive models incorporating relevant clinical and social features can provide meaningful insights into complex interrelated mechanisms of cardiovascular disease (CVD) risk and progression and the influence of environmental exposures on adverse outcomes. The purpose of this targeted review (2018-2019) was to examine the extent to which present-day advanced analytics, artificial intelligence, and machine learning models include relevant variables to address potential biases that inform care, treatment, resource allocation, and management of patients with CVD.

Methods

PubMed literature was searched using the prespecified inclusion and exclusion criteria to identify and critically evaluate primary studies published in English that reported on predictive models for CVD, associated risks, progression, and outcomes in the general adult population in North America. Studies were then assessed for inclusion of relevant social variables in the model construction. Two independent reviewers screened articles for eligibility. Primary and secondary independent reviewers extracted information from each full-text article for analysis. Disagreements were resolved with a third reviewer and iterative screening rounds to establish consensus. Cohen's kappa was used to determine interrater reliability.

Results

The review yielded 533 unique records where 35 met the inclusion criteria. Studies used advanced statistical and machine learning methods to predict CVD risk (10, 29%), mortality (19, 54%), survival (7, 20%), complication (10, 29%), disease progression (6, 17%), functional outcomes (4, 11%), and disposition (2, 6%). Most studies incorporated age (34, 97%), sex (34, 97%), comorbid conditions (32, 91%), and behavioral risk factor (28, 80%) variables. Race or ethnicity (23, 66%) and social variables, such as education (3, 9%) were less frequently observed.

Conclusions

Predictive models should adjust for race and social predictor variables, where relevant, to improve model accuracy and to inform more equitable interventions and decision making.

Management of cardiac diseases in liver transplant recipients: Comprehensive review and multidisciplinary practice-based recommendations

Cardiac diseases are one of the most common causes of morbidity and mortality following liver transplantation (LT). Prior studies have shown that cardiac diseases affect close to one-third of liver transplant recipients (LTRs) long term and that their incidence has been on the rise. This rise is expected to continue as more patients with advanced age and/or non-alcoholic steatohepatitis undergo LT. In view of the increasing disease burden, a multidisciplinary initiative was developed to critically review the existing literature (between January 1, 1990 and March 17, 2021) surrounding epidemiology, risk assessment, and risk mitigation of coronary heart disease, arrhythmia, heart failure, and valvular heart disease and formulate practice-based recommendations accordingly. In this review, the expert panel emphasizes the importance of optimizing management of metabolic syndrome and its components in LTRs and highlights the cardioprotective potential for the newer diabetes medications (e.g., sodium glucose transporter-2 inhibitors) in this high-risk population. Tailoring the multidisciplinary management of cardiac diseases in LTRs to the cardiometabolic risk profile of the individual patient is critical. The review also outlines numerous knowledge gaps to pave the road for future research in this sphere with the ultimate goal of improving clinical outcomes.

Liver transplant with controlled donors after circulatory death with normothermic regional perfusion and brain dead donors: A multicenter cohort study of transfusion, one-year graft survival and mortality

BACKGROUND

Controlled donation after circulatory death (cDCD) has expanded the donor pool for liver transplantation (LT). However, transfusion requirements and perioperative outcomes should be elucidated. The aim of this multicenter study was to assess red blood cell (RBC) transfusions, one-year graft and patient survival after LT after cDCD with normothermic regional perfusion (NRP) compared with donors after brain death (DBD).

METHODS

591 LT carried out in ten centers during 2019 were reviewed. Thromboelastometry was used to manage coagulation and blood product transfusion in all centers. Normothermic regional perfusion was the standard technique for organ recovery.

RESULTS

447 patients received DBD and 144 cDCD with NRP. Baseline MCF Extem was lower in the cDCD group There were no differences in the percentage of patients (63% vs. 61% p = 0.69), nor in the number of RBC units transfused (4.7 (0.2) vs 5.5 (0.4) in DBD vs cDCD, p = 0.11. Twenty-six patients (6%) died during admission for LT in the DBD group compared with 3 patients (2%) in the cDCD group (p = 0.15). To overcome the bias due to a worse coagulation profile in cDCD recipients, matched samples were compared. No differences in baseline laboratory data, or in intraoperative use of RBC or one-year outcome data were observed between DBD and cDCD recipients.

CONCLUSIONS

cDCD with NRP is not associated with increased RBC transfusion. No differences in graft and patient survival between cDCD and DBD were found. Donors after controlled circulatory death with NRP can increasingly be utilized with safety, improving the imbalance between organ donors and the ever-growing demand.

New onset nonischemic cardiomyopathy post liver transplantation

A new onset acute heart failure (HF) with a sudden drop in the left ventricular ejection fraction (LVEF) post orthotopic liver transplant (LT) is a rare but a potentially fatal complication. Because in most of the cases there is no evidence of coronary thrombosis, it can be classified as nonischemic cardiomyopathy. More specifically, clinical presentation of this syndrome shares many features with stress-induced or takotsubo cardiomyopathy. The known factors that predispose these patients to acute HF during or shortly after LT include cirrhotic cardiomyopathy, rapid hemodynamic changes during LT surgery, and the large concentrations of catecholamines, either administered or released endogenously during surgery. The hemodynamic changes during surgery, such as the drop in preload during the anhepatic phase (occasionally requiring massive transfusions and vasopressors) and subsequent increase in preload with acidic and hyperkalemic plasma in the reperfusion phase, lead to rapid electrolyte and hemodynamic shifts. In several cases, intraoperative onset of HF, with or without ventricular arrythmia, could be timed to the reperfusion phase (and occasionally in the anhepatic and pre-anhepatic phases). In other cases, the HF syndrome started hours to days post-surgery. Recovery of cardiac function occurred in the majority of patients during the same admission; however, these patients generally need significantly longer hospitalizations and aggressive supportive care (occasionally requiring mechanical ionotropic and ventilatory support). If recover, the patients have a similar 1-year mortality as those LT patients that did not have this complication. Because no reliable risk stratification currently exists, intraoperative transesophageal echocardiography might be the most dependable way of detecting and addressing this syndrome promptly. Given the mechanism of takotsubo cardiomyopathy, beta-blockade and a preferential use of non-catecholaminergic vasopressors may be a reasonable way to manage this syndrome.

Prevalence and prognostic value of cirrhotic cardiomyopathy as defined according to the proposed new classification

Aim of the study

Prevalence and prognostic relevance of cirrhotic cardiomyopathy (CCM), as defined according to the new core criteria proposed in 2019, are still unknown. We investigated this relevant issue in a large cohort of cirrhotic patients.

Material and methods

We retrospectively interrogated a data set of 162 collected cirrhotic patients followed up for at least 6 years, who underwent standard Doppler echocardiography and were compared with 46 healthy subjects. Left ventricular (LV) geometry, systo-diastolic function, global longitudinal strain and the main hemodynamic parameters were assessed according to current guidelines. Systolic dysfunction was diagnosed if LV ejection fraction (LVEF) ≤ 50% and/or global longitudinal strain (GLS) < 18% or > 22%.

Results

Adequate echocardiographic images permitting speckle tracking analysis were available in 83 patients. No patient presented LVEF ≤ 50%, GLS < 18% or > 22% was evident in 25%, advanced diastolic dysfunction was evident in 10%. Overall the prevalence of CCM was 29%. Patients with and without CCM presented similar clinical, biochemical, hemodynamic and echocardiographic features at baseline and similar incidence of death or type 1 hepatorenal syndrome at follow-up.

Conclusions

According to the new criteria CCM is detected in 29%, mainly due to altered GLS at rest, but without prognostic relevance and therefore useless for the clinical management of cirrhotic patients. We propose to modify the criteria by removing the LVEF assessment and adding also a stress test assessing the cardiac contractile reserve to distinguish patients with a blunted cardiac response, which could present a worst prognosis.

Utility of Framingham Score for Optimizing Preoperative Evaluation Among Patients Undergoing Liver Transplant Evaluation

BACKGROUND

Cardiac testing of candidates for liver transplant (LT) requires balancing risks and benefits of cardiac procedures. The goal of this study was to evaluate the utility of the Framingham score (FS) for optimizing preoperative risk stratification for coronary artery disease (CAD).

METHODS

In this single-center retrospective study of 615 adults undergoing LT evaluation from 2016 to 2019, data of preoperative evaluation, post-LT 1-year mortality, and post-LT cardiac events were reviewed. Patients >30 years of age with normal echocardiogram underwent FS calculation. Elevated FS (≥35%) patients were triaged to undergo angiogram for CAD evaluation; FS <35% patients underwent stress testing as initial CAD evaluation.

RESULTS

Of 615 patients referred for LT, 481 underwent cardiac testing. Ninety-five were excluded from the FS pathway because of age, abnormal baseline echocardiogram, or known CAD. Of the remaining 386 patients in the FS pathway, 342 had a low FS and 44 had a high FS. In patients with low FS, 90% underwent stress testing as initial test; 16% underwent invasive testing at some time. In those with elevated FS, 59% underwent invasive testing as initial test. Listing rate and posttransplant outcomes were similar between patients with low and high FS.

CONCLUSION

We demonstrated the feasibility of a simple algorithmic evaluation process using FS for optimizing pre-LT risk stratification for CAD. Although exceptions to the protocol occur, the proposed protocol allows for a streamlined approach by prioritizing testing based on cardiac risk. This approach may maximize diagnostic yield while limiting invasive procedures.

The prevalence of cirrhotic cardiomyopathy according to different diagnostic criteria

BACKGROUND AND AIMS

Recently published criteria by 2019 Cirrhotic Cardiomyopathy Consortium set a lower threshold for reduced ejection fraction to diagnose systolic dysfunction in cirrhotic patients, and stress testing was replaced by echocardiography strain imaging. The criteria to diagnose diastolic dysfunction are in general concordant with the 2016 ASE/EACVI guidelines and differ considerably from the 2005 Montreal recommendations. We aimed to assess the prevalence of cirrhotic cardiomyopathy according to different diagnostic criteria.

METHODS

Cirrhotic patients without another structural heart disease, arterial hypertension, portal vein thrombosis, HCC outside Milan criteria and presence of TIPS were enrolled. Speckle-tracking echocardiography was performed by EACVI certified investigators.

RESULTS

A total of 122 patients with cirrhosis fulfilled the inclusion criteria. Overall prevalence of cirrhotic cardiomyopathy was similar for 2005 Montreal and 2019 CCC: 67.2% vs 55.7% (P = .09); and significantly higher compared to 2009 ASE/EACVI criteria: 67.2% vs 35.2% (P < .0001) and 55.7% vs 35.2% (P = .002) respectively. Significantly more patients had diastolic dysfunction according to the 2005 Montreal compared to the 2009 ASE/EACVI and 2019 CCC criteria: 64.8% vs 32.8% (P < .0001) and 64.8% vs 7.4% (P < .0001). Systolic dysfunction was more frequently diagnosed according to 2019 CCC criteria compared to 2005 Montreal (53.3% vs 16.4%,P < .0001) or ASE/EACVI criteria (53.3% vs 4.9%,P < .0001).

CONCLUSION

Cirrhotic cardiomyopathy was present in around 60% of cirrhotic patients when applying the hepatological criteria. A considerably higher prevalence of systolic dysfunction according to the 2019 CCC criteria was observed. Long-term follow-up studies are needed to establish the validity of these criteria to predict clinically relevant outcomes.

Cirrhotic Cardiomyopathy - A Veiled Threat

Cirrhotic cardiomyopathy (CCM) is defined as cardiac dysfunction in patients with liver cirrhosis without pre-existing cardiac disease. According to the definition established by the World Congress of Gasteroenterology in 2005, the diagnosis of CCM includes criteria reflecting systolic dysfunction, impaired diastolic relaxation, and electrophysiological disturbances. Because of minimal or even absent clinical symptoms and/or echocardiographic signs at rest according to the 2005 criteria, CCM diagnosis is often missed or delayed in most clinically-stable cirrhotic patients. However, cardiac dysfunction progresses in time and contributes to the pathogenesis of hepatorenal syndrome and increased morbidity and mortality after liver transplantation, surgery or other invasive procedures in cirrhotic patients. Therefore, a comprehensive cardiovascular assessment using newer techniques for echocardiographic evaluation of systolic and diastolic function, allowing the diagnosis of CCM in the early stage of subclinical cardiovascular dysfunction, should be included in the screening process of liver transplant candidates and patients with cirrhosis in general. The present review aims to summarize the most important pathophysiological aspects of CCM, the usefulness of contemporary cardiovascular imaging techniques and parameters in the diagnosis of CCM, the current therapeutic options, and the importance of early diagnosis of cardiovascular impairment in cirrhotic patients.

Acute heart failure after liver transplantation: A narrative review

Acute heart failure (AHF) is an under recognized yet potentially lethal complication after liver transplantation (LT) surgery. The increase in incidence of liver transplantation amongst high-risk patients and the leniency in the criteria for transplantation, predisposes these patients to postoperative AHF and the antecedent morbidity and mortality. The inability of conventional preoperative cardiovascular testing to accurately identify patients at risk for post-LT AHF poses a considerable challenge to clinicians caring for these patients. Even if high-risk patients are identified, there is considerable ambiguity in the candidacy for transplantation as well as optimization strategies that could potentially prevent the development of AHF in the postoperative period. The intraoperative and postoperative management of patients who develop AHF is also challenging and requires a well-coordinated multidisciplinary approach. The use of mechanical circulatory support in patients with refractory heart failure has the potential to improve outcomes but its use in this complex patient population can be associated with significant complications and requires a stringent risk-benefit analysis on a case-by-case basis.