Cardiac morbidity and mortality related to orthotopic liver transplantation

Use of Transesophageal Echocardiography During Orthotopic Liver Transplantation: Simplifying the Procedure

The intraoperative management of patients undergoing orthotopic liver transplantation (OLT) is influenced by the cardiovascular manifestations typically found in the context of end-stage liver disease, by the presence of concomitant cardiovascular disease, and by the significant hemodynamic changes that occur during surgery. Hypotension and intraoperative blood pressure fluctuations during OLT are associated with liver graft dysfunction, acute kidney failure, and increased risk of 30-d mortality. Patients also frequently present hemodynamic instability due to various causes, including cardiac arrest. Recent evidence has shown transesophageal echocardiography (TEE) to be a useful minimally invasive monitoring tool in patients undergoing OLT that gives valuable real-time information on biventricular function and volume status and can help to detect OLT-specific complications or situations. TEE also facilitates rapid diagnosis of life-threatening conditions in each stage of OLT, which is difficult to identify with other types of monitoring commonly used. Although there is no consensus on the best approach to intraoperative monitoring in these patients, intraoperative TEE is safe and useful and should be recommended during OLT, according to experts, for assessing hemodynamic changes, identifying possible complications, and guiding treatment with fluids and inotropes to achieve optimal patient care.

Screening Modalities for Coronary Artery Disease in Liver Transplant Candidates: A Review of the Literature

Patients with cirrhosis undergoing liver transplant (LT) are at high risk of postoperative cardiopulmonary complications. It is known that patients with coronary artery disease (CAD) have greater rates of post-LT morbidity and mortality than patients without CAD. Thus, identifying significant CAD in LT candidates is of the utmost importance to optimize survival posttransplant. Consensus is lacking on the ideal screening test for CAD in LT candidates. Traditional exercise and many pharmacologic stress tests are impractical and inaccurate in patients with cirrhosis due to their unique physiology. The purpose of this review is to describe different screening modalities for CAD among LT candidates. The background, diagnostic accuracy, and limitations of each screening modality are described to achieve this goal.

The Edge of Unknown: Postoperative Critical Care in Liver Transplantation

Perioperative care of patients undergoing liver transplantation (LT) is very complex. Metabolic derangements, hypothermia, coagulopathy and thromboses, severe infections, and graft dysfunction can affect outcomes. In this manuscript, we discuss several perioperative problems that can be encountered in LT recipients. The authors present the most up-to-date information regarding predicting and treating hemodynamic instability, coagulation monitoring and management, postoperative ventilation strategies and early extubation, management of infections, and ESLD-related pulmonary complications. In addition, early post-transplant allograft dysfunction will be discussed.

Cardiac imaging for the assessment of patients being evaluated for liver transplantation

Cardiac risk assessment prior to liver transplantation has become widely accepted. With the emergence of nonalcoholic steatohepatitis among the leading causes of end-stage liver disease and the steady rise of the age of liver transplant recipients, the burden of cardiovascular diseases has markedly increased in this population. Selecting appropriate liver transplant candidates is crucial due to the increasing demand for scarce donor organs. The use of noninvasive cardiac imaging for pre-operative assessment of the cardiovascular status of liver transplant recipients has been on the rise, yet the optimal assessment strategy remains an area of active debate. In this review, we examine the relevant literature pertaining to the diagnostic and prognostic applications of noninvasive cardiac imaging in this population. We also propose a simple literature-based evaluation algorithm for CAD surveillance in liver transplant candidates.

Propofol prevents further prolongation of QT interval during liver transplantation

Here, we aimed to compare the effects of two anesthetic methods (desflurane inhalation anesthesia vs. propofol-based total intravenous anesthesia (TIVA)] on corrected QT interval (QTc) values during living donor liver transplantation. Altogether, 120 patients who underwent living donor liver transplantation were randomized to either the desflurane or TIVA group. The primary outcome was intraoperative QTc change. Other electrocardiogram, hemodynamic findings and postoperative outcomes were examined as secondary outcomes. QTc values were prolonged intraoperatively in both groups; however, the change was smaller in the TIVA group than in the desflurane group (P_{Group × Time} < 0.001). More patients had QTc values of > 500 ms in the desflurane group than in the TIVA group (63.3% vs. 28.3%, P < 0.001). In patients with preoperative QTc prolongation, QTc was further prolonged in the desflurane group, but not in the TIVA group (P_{Group × Time} < 0.001). Intraoperative norepinephrine and vasopressin use were higher in the desflurane group than in the TIVA group. Propofol-based TIVA may reduce QTc prolongation during living donor liver transplantation compared to that observed with desflurane inhalational anesthesia, particularly in patients with preoperative QTc prolongation. Additionally, patients managed with propofol-based TIVA required less vasopressor during the procedure as compared with those managed with desflurane inhalational anesthesia.

Diagnosis and Management of Cirrhotic Cardiomyopathy

BACKGROUND

Cirrhotic cardiomyopathy refers to the structural and functional changes in the heart leading to either impaired systolic, diastolic, electrocardiographic, and neurohormonal changes associated with cirrhosis and portal hypertension. Cirrhotic cardiomyopathy is present in 50% of patients with cirrhosis and is clinically seen as impaired contractility, diastolic dysfunction, hyperdynamic circulation, and electromechanical desynchrony such as QT prolongation. In this review, we will discuss the cardiac physiology principles underlying cirrhotic cardiomyopathy, imaging techniques such as cardiac magnetic resonance imaging and scintigraphy, cardiac biomarkers, and newer echocardiographic techniques such as tissue Doppler imaging and speckle tracking, and emerging treatments to improve outcomes.

METHODS

We reviewed available literature from MEDLINE for randomized controlled trials, cohort studies, cross-sectional studies, and real-world outcomes using the search terms "cirrhotic cardiomyopathy," "left ventricular diastolic dysfunction," "heart failure in cirrhosis," "liver transplantation," and "coronary artery disease".

RESULTS

Cirrhotic cardiomyopathy is associated with increased risk of complications such as hepatorenal syndrome, refractory ascites, impaired response to stressors including sepsis, bleeding or transplantation, poor health-related quality of life and increased morbidity and mortality. The evaluation of cirrhotic cardiomyopathy should also guide the feasibility of procedures such as transjugular intrahepatic portosystemic shunt, dose titration protocol of betablockers, and liver transplantation. The use of targeted heart rate reduction is of interest to improve cardiac filling and improve the cardiac output using repurposed heart failure drugs such as ivabradine. Liver transplantation may also reverse the cirrhotic cardiomyopathy; however, careful cardiac evaluation is necessary to rule out coronary artery disease and improve cardiac outcomes in the perioperative period.

CONCLUSION

More data are needed on the new diagnostic criteria, molecular and biochemical changes, and repurposed drugs in cirrhotic cardiomyopathy. The use of advanced imaging techniques should be incorporated in clinical practice.

What's New in Cirrhotic Cardiomyopathy?-Review Article

Cirrhotic cardiomyopathy (CCM) is a relatively new medical term. The constant development of novel diagnostic and clinical tools continuously delivers new data and findings about this broad disorder. The purpose of this review is to summarize current facts about CCM, identify gaps of knowledge, and indicate the direction in which to prepare an updated definition of CCM. We performed a review of the literature using scientific data sources with an emphasis on the latest findings. CCM is a clinical manifestation of disorders in the circulatory system in the course of portal hypertension. It is characterized by impaired left ventricular systolic and diastolic dysfunction, and electrophysiological abnormalities, especially QT interval prolongation. However, signs and symptoms reported by patients are non-specific and include reduced exercise tolerance, fatigue, peripheral oedema, and ascites. The disease usually remains asymptomatic with almost normal heart function, unless patients are exposed to stress or exertion. Unfortunately, due to the subclinical course, CCM is rarely recognized. Orthotopic liver transplantation (OLTx) seems to improve circulatory function although there is no consensus about its positive effect, with reported cases of heart failure onset after transplantation. Researchers indicate a careful pre-, peri-, and post-transplant cardiac assessment as a crucial point in detecting CCM and improving patients’ prognosis. There is also an urgent need to update the CCM definition and establish a diagnostic algorithm for early diagnosis of CCM as well as a specific treatment of this condition.

Impact of nutritional status on prevalence of left ventricular hypertrophy in children undergoing liver transplant

OBJECTIVE

We sought to (1) determine the prevalence of cardiac changes in patients with ESLD awaiting OLT (2) determine relationship between nutritional indices and cardiac changes.

METHODS

Retrospective review of transthoracic ECHO, clinical and nutritional information of pediatric patients evaluated for OLT. ECHO was analyzed for LVH, defined as LVMI > 95 g/m^2.7 and/or RWT > 0.42. These findings were correlated with age, ESLD etiology, growth and nutritional parameters as well as pre- and post-OLT.

RESULTS

Sixty-five patients were included, all had normal left ventricular systolic function. Nine patients (14%) had LVMI > 95 g/m^2.7 , five patients (8%) had RWT > 0.42, none met both criteria. None had thickened interventricular septal wall. Fourteen patients (20%) had significant left ventricular dilation. Nutritional deprivation was modestly present-weight under third percentile in 22%, length under third percentile in 24%, and both weight and length under third percentile in 17%. There were 12 patients (17%) with MUAC below two standard deviations for age; of these one had an elevated LVMI and another had an RWT > 0.42.

CONCLUSIONS

In this contemporary cross-sectional evaluation, a smaller proportion of patients with ESLD had LVH in contrast to prior studies. Despite a comparable disease burden, our cohort had better nutritional status. Though there was a trend between nutritional and LVH indices, this correlation may be better assessed prospectively in a larger cohort.

Cirrhotic Cardiomyopathy and Cardiac Failure after Liver Transplantation: A Case Series

Preoperative cardiac functional assessment has been a long-debated topic in liver transplantation. Debate continues to exist regarding the use of invasive cardiac studies, and the utility of each prior to transplant. Despite the debate, a 7% mortality can be attributed to significant cardiac events. We present a case series of 3 patients who underwent orthotopic liver transplantation and developed significant cardiac dysfunction postoperatively. All preoperative cardiac assessments in each patient were normal with no hemodynamically significant abnormalities. Interestingly enough, each patient developed cardiac failure due to completely different diagnoses.

Extracorporeal Membrane Oxygenation in Pediatric Liver Transplantation: A Multicenter Linked Database Analysis and Systematic Review of the Literature

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) can be used to maintain oxygen delivery and provide hemodynamic support in case of circulatory and respiratory failure. Although the role of ECMO has emerged in the setting of adult liver transplantation (LT), data in children are limited. We aimed to describe the characteristics and outcomes of children receiving ECMO support at the time of or following LT.

METHODS

All pediatric LT recipients (≤20 y) requiring ECMO support peri-/post-LT were identified from a linked Pediatric Health Information System/Scientific Registry of Transplant Recipients dataset (2002-2018). The Kaplan-Meier method and Cox regression analysis were used to assess post-ECMO survival. A systematic literature review was conducted in accordance with the PRISMA statement.

RESULTS

Thirty-four children required ECMO peri-/post-LT. The median time from LT to ECMO was 5 d (interquartile range, 0.0-12.3), and the median ECMO duration was 1 d (interquartile range, 1.0-6.3). Children started on ECMO within 1 d of LT exhibited superior survival compared with those started on ECMO later (P = 0.03). When adjusting for recipient weight, increasing time from LT to ECMO initiation was associated with increased risk of mortality (hazard ratio, 1.03; 95% confidence interval, 1.00-1.06; P = 0.049). Overall, 55.9% (n = 19 of 34) of the patients survived. Twenty-two children receiving ECMO in the peri-/post-LT period were systematically reviewed, and 15 of them survived (68.2%).

CONCLUSIONS

With an encouraging >55% patient survival at 6 mo, ECMO should be considered as a viable option in pediatric LT recipients with potentially reversible severe respiratory or cardiovascular failure refractory to conventional treatment.

Prognostic Value of Computed Tomographic Coronary Angiography for Long-Term Major Adverse Cardiac Events after Liver Transplantation

Computed tomographic coronary angiography (CTCA) has prognostic value for early major adverse cardiac events (MACEs) after liver transplantation. However, the association between CTCA and long-term MACEs in liver transplant (LT) recipients remains unknown. We evaluated the association between CTCA and long-term MACEs within 5 years after living donor liver transplantation (LDLT). A total of 628 LDLT recipients who underwent CTCA were analyzed between 2010 and 2012. MACEs were investigated within 5 years after LDLT. The factors associated with long-term MACEs in transplant recipients were evaluated. Only 48 (7.6%) patients developed MACEs. In the Fine and Gray competing risk regression, a coronary artery calcium score (CACS) of >400 combined with obstructive coronary artery disease (CAD) (subdistribution hazard ratio: 5.01, 95% confidence interval: 2.37–10.58, p < 0.001), age (1.05, 1.01–1.10, p = 0.018), diabetes mellitus (2.43, 1.37–4.29, p = 0.002), dyslipidemia (2.45, 1.23–4.70, p = 0.023), and creatinine (1.19, 1.08–1.30, p < 0.001) were independently associated with long-term MACEs. CACS (>400) combined with obstructive CAD may be associated with MACEs within 5 years after LDLT, suggesting the importance of preoperative noninvasive CTCA in LT recipients. The evaluation of coronary artery stenosis on CTCA combined with CACS may have a prognostic value for long-term MACEs in LT recipients.

Cardiovascular mortality following liver transplantation: predictors and temporal trends over 30 years

AIMS

There has been significant evolution in operative and post-transplant therapies following liver transplantation (LT). We sought to study their impact on cardiovascular (CV) mortality, particularly in the longer term.

METHODS AND RESULTS

A retrospective cohort study was conducted of all adult LTs in Australia and New Zealand across three 11-year eras from 1985 to assess prevalence, modes, and predictors of early (≤30 days) and late (>30 days) CV mortality. A total of 4265 patients were followed-up for 37 409 person-years. Overall, 1328 patients died, and CV mortality accounted for 228 (17.2%) deaths. Both early and late CV mortality fell significantly across the eras (P < 0.001). However, CV aetiologies were consistently the leading cause of early mortality and accounted for ∼40% of early deaths in the contemporary era. Cardiovascular deaths occurred significantly later than non-cardiac aetiologies (8.8 vs. 5.2 years, P < 0.001). On multivariable Cox regression, coronary artery disease [hazard ratio (HR) 4.6, 95% confidence interval (CI) 1.2-21.6; P = 0.04] and era of transplantation (HR 0.44; 95% CI 0.28-0.70; P = 0.01) were predictors of early CV mortality, while advancing age (HR 1.05, 95% CI 1.02-1.10; P = 0.005) was an independent predictors of late CV mortality. Most common modes of CV death were cardiac arrest, cerebrovascular events, and myocardial infarction.

CONCLUSION

Despite reductions in CV mortality post-LT over 30 years, they still account for a substantial proportion of early and late deaths. The late occurrence of CV deaths highlights the importance of longitudinal follow-up to study the efficacy of targeted risk-reduction strategies in this unique patient population.

Coronary artery calcium on standard chest computed tomography predicts cardiovascular events after liver transplantation

AIMS

Cardiac complications are a leading cause of mortality after orthotopic liver transplantation (LT) and pre-operative risk stratification is challenging. We evaluated whether coronary artery calcium (CAC) score calculated on a standard (non-thin layer, non-ECG gated) chest computed tomography (CT) predicted cardiac outcome after LT.

METHODS

We included a consecutive series of LT recipients who underwent pre-operative cardiac evaluation including stress-testing or cardiac catheterization in high-risk patients. Patients with a history of coronary artery disease or coronary revascularization were excluded. The CAC score was calculated from the chest CT routinely performed before LT. CAC values were not available at the time of pre-transplant cardiac evaluation and did not affect LT eligibility. The primary end-point included peri-operative arrhythmic cardiac arrest and sustained ventricular arrhythmias; heart failure, myocardial infarction and cardiac death within 1-year after LT.

RESULTS

The study population consisted of 301 patients (median age 56 years, 76% males). At chest CT, 49% had CAC = 0; 27% had CAC = 1-99, 15% had CAC = 100-399 and 9% CAC > 400. The primary end-point incidence increased from 7% in patients with CAC = 0 to 27% in patients with CAC > 400 (p = 0.007). At multivariable analysis including traditional risk factors, CAC remained an independent predictor of cardiac events (p = 0.01).

CONCLUSIONS

CAC score calculated on a standard chest CT stratified the risk of cardiac events in patients who underwent LT after negative pre-transplant cardiac evaluation. These findings suggest that evaluation of CAC from a standard chest CT performed for other reasons can be used as an early cardiac risk stratification tool before LT.

Cardiac Risk Assessment in Liver Transplant Candidates: Current Controversies and Future Directions

In the changing landscape of liver transplantation (LT), we are now evaluating older and sicker patients with more cardiovascular comorbidities, and the spectrum of cardiovascular disease is uniquely physiologically impacted by end-stage liver disease. Cardiac complications are now the leading cause of morbidity and mortality in LT recipients, and the pretransplant risk is exacerbated immediately during the transplant operation and continues long term under the umbrella of immunosuppression. Accurate risk estimation of cardiac complications before LT is paramount to guide allocation of limited health care resources and to improve both short-term and long-term clinical outcomes for patients. Current screening and diagnostic testing are limited in their capacity to accurately identify early coronary disease and myocardial dysfunction in persons with end-stage liver disease physiology. Furthermore, a number of testing modalities have not been evaluated in patients with end-stage liver disease. As a result, there is wide variation in cardiac risk assessment practices across transplant centers. In this review, we propose a definition for defining cardiac events in LT, evaluate the current evidence for surgery-related, short-term and long-term cardiac risk assessment in LT candidates, propose an evidence-based testing algorithm, and highlight specific gaps in knowledge and current controversies, identifying areas for future research.

Transplant of Elderly Patients: Is There an Upper Age Cutoff?

Increased life expectancy and advances in the care of chronic liver disease has increased the number of elderly patients needing liver transplant. Organ donation policies prioritize transplant to the sickest. There is an ongoing debate with regard to balancing the principles of equity and utility. Several hospitals have adopted center-specific policies and there has been an increased trend of transplant in elderly patients since 2002. Appropriate patient selection and long-term outcomes in the setting of limited organ availability pose several challenges. This article reviews the data and discusses the pros and cons of transplants in the elderly.

Cardiac and Pulmonary Vascular Risk Stratification in Liver Transplantation

Cardiovascular disease complications are the leading cause of early (short-term) mortality among liver transplant recipients. The increasingly older candidate pool has multiple comorbidities necessitating cardiac and pulmonary vascular disease risk stratification of patients for optimal allocation of scarce donor livers. Arrhythmias, heart failure, stroke, and coronary artery disease are common pretransplant cardiovascular comorbidities and contribute to cardiovascular complications after liver transplant. Valvular heart disease and portopulmonary hypertension present intraoperative challenges during liver transplant surgery. The Cardiovascular Risk in Orthotopic Liver Transplantation score estimates the risk of cardiovascular complications in liver transplant candidates within the first year after transplant.

Coronary Computed Tomography Angiography Demonstrates a High Burden of Coronary Artery Disease Despite Low-Risk Nuclear Studies in Pre-Liver Transplant Evaluation

We investigated the presence and severity of coronary artery disease (CAD) in orthotopic liver transplantation (OLT) candidates using coronary artery calcium score (CACS) and coronary computed tomography angiography (CCTA) as compared with the prevalence of normal and abnormal single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI). A total of 140 prospective OLT candidates without known CAD underwent coronary artery calcium (CAC) scans with (n = 77) or without CCTA and coronary computed tomography angiography-derived fractional flow reserve (FFR_CT ; n = 57) using a dual-source computed tomography (CT) and were followed for 2.6 ± 1.4 years. Coronary plaque was quantified using the segment-involvement score (SIS) and segment stenosis score (SSS). The mean age was 59 ± 6 years, and 65.0% of patients were male. Mean Agatston CACS was 367 ± 653, and 15.0% of patients had CACSs of 0; 83.6% received a SPECT MPI, of which 95.7% were interpreted as normal/probably normal. By CCTA, 9.1% had obstructive CAD (≥70% stenosis), 67.5% had nonobstructive CAD, and 23.4% had no CAD. Nonobstructive CAD was diffuse with mean SIS 3.0 ± 2.9 and SSS 4.5 ± 5.4. Only 14 patients had high risk-findings (severe 3v CAD, n = 4, CACS >1000 n = 10) that prompted X-ray angiography in 3 patients who had undergone CCTA, resulting in revascularization of a high-risk obstruction in 1 patient who had a normal SPECT study. Patients with end-stage liver disease have a high prevalence of nonobstructive CAD by CCTA, which is undiagnosed by SPECT MPI, potentially underestimating cardiovascular risk. Deferring X-ray angiography unless high-risk CCTA findings are present is a potential strategy for avoiding unnecessary X-ray angiography.

Cardiovascular and metabolic disease in the liver transplant recipient

Liver transplantation has led to great improvements in long-term survival in patients with decompensated liver disease and hepatocellular carcinoma. Cardiovascular disease is the leading cause of non-graft-related deaths and has increased prevalence in liver allograft recipients. This is partly secondary to higher post-transplant rates of metabolic risk factors-notably obesity, hypertension, dyslipidemia, and diabetes mellitus, which comprise metabolic syndrome. Post-transplantation metabolic syndrome is expected to be a growing factor in morbidity and mortality as transplant candidates trend older, the rates of metabolic risk factors in the general population increase, non-alcoholic steatohepatitis grows disproportionally as an indication for transplantation, and post-transplantation survival lengthens. This review discusses the incidence and contributory factors for post-transplant increases in metabolic disease, as well as the burden of cardiovascular disease in the liver allograft recipient. Patients with pre-transplant diabetes or obesity are at particularly high risk for post-transplant metabolic syndrome, and would likely benefit from closer surveillance and more aggressive medical management of risk factors. In metabolic disease resistant to initial medical therapies, tailoring of immunosuppressive regimens may further assist in minimizing long-term cardiovascular disease, although this must be done with caution to avoid worsening the risk of graft failure.

Safety and Outcomes of Combined Liver Transplantation and Cardiac Surgery in Cirrhosis

BACKGROUND

Decompensation of liver function after cardiac surgery in patients with cirrhosis has resulted in high morbidity and mortality. A treatment strategy, for which there is a scarcity of data in the literature, encompasses combined liver transplantation and cardiac surgery.

METHODS

We performed a retrospective analysis of prospectively collected data on 15 patients who underwent combined liver transplantation and cardiac surgery between 2005 to 2017 at our institution.

RESULTS

Between 2005 and 2017, 15 patients with cirrhosis and coronary artery disease or valve disease were identified who underwent combined liver transplantation and cardiac surgery. The cardiac disease was considered severe enough to preclude liver transplantation alone. Likewise, the advanced cirrhosis precluded cardiac surgery alone. Eighty percent of the patients were male and average age was 60 years. Six patients had coronary artery disease, 2 patients had severe aortic stenosis and coronary artery disease, 1 patient had severe mitral regurgitation and coronary artery disease, 2 patients had severe aortic stenosis, 1 patient had mitral valve prolapse, and 3 patients had severe aortic insufficiency. The mean model for end-stage liver disease score was 24. Four subjects were Child-Pugh class B, and 11 were class C. One-year survival was 73.3%.

CONCLUSIONS

Combined liver transplant and cardiac surgery is feasible in this selected, otherwise inoperable, patient population with an acceptable early and midterm survival when performed in high volume centers with a cohesive multidisciplinary team.

SPECT myocardial perfusion imaging in liver transplantation candidates

BACKGROUND

The optimal cardiovascular evaluation prior to liver transplantation remains controversial and includes stress echocardiography, stress MPI, cardiac CTA, and coronary angiography. This study summarizes our experience of the past decade using SPECT MPI in patients with end-stage liver disease, including patient characteristics, stress testing protocols, test results, the need for repeat testing, and downstream testing.

METHODS

All patients who underwent a clinically indicated stress SPECT MPI study as part of their pre-liver transplant evaluation from 2004 to 2014 were reviewed from the Nuclear Cardiology database. Results of perfusion imaging, repeat testing, subsequent angiography, and need for revascularization were reviewed.

RESULTS

A total of 2500 patients were referred for SPECT MPI, of those 111 had known CAD and 271 underwent more than one MPI study. Compared to other patients undergoing stress MPI, pre-liver transplant patients were younger, had fewer cardiac risk factors and lower prevalence of prior cardiac history, and used pharmacologic stress more often. During the study decade, patient age increased, prevalence of hypertension increased and smoking decreased, prevalence of known CAD increased, and the number of abnormal studies decreased. Abnormal perfusion results were present in 7.8% of pre-liver transplant patients compared to 34.3% of all other patients. In a multivariate model, age and lower ejection fraction were associated with an abnormal MPI result. Of the 64 patients who underwent subsequent invasive or non-invasive coronary angiography after an abnormal MPI, obstructive CAD was diagnosed in 25 patients (1.0%), non-obstructive CAD was diagnosed in 23 patients (0.9%), and normal coronaries found in 16 patients (0.6%); a total of 18 (0.7%) of these underwent coronary revascularization. The average time to repeat testing was 27.2 ± 17.9 months. In a multivariate model, younger age and exercise stress were associated with repeat testing. In only 17 patients out of 271 with a normal initial perfusion, the repeat study became abnormal. The use of stress-first imaging was successful in 80% of patients with a reduction in Tc-99m dose from 39.1 to 18.3 mCi.

CONCLUSION

Abnormal SPECT MPI results in candidates for liver transplantation are infrequent compared to non-liver transplant patients and the incidence of obstructive CAD on subsequent angiography even less. Repeat testing in those on the transplant waiting list after initial normal test results appears to be of limited value. Stress-first protocols may be considered for the majority of these patients to reduce testing time and radiation exposure.

Assessment of Malnutrition, Sarcopenia and Frailty in Patients with Cirrhosis: Which Tools Should We Use in Clinical Practice?

Malnutrition is a common comorbidity in patients with cirrhosis. Its prognostic value is indisputable as it greatly affects the evolution of liver diseases. It has a major impact on both morbi-mortality before and after liver transplantation. Being now integrated in the definition of malnutrition and recognized as a new entity in the international classification of diseases, physicians have taken great interest in sarcopenia. Its negative consequences on the fate of patients with cirrhosis are well-demonstrated. The concept of frailty has recently been enlarged to chronic liver diseases as symptoms of impaired global physical functioning. In this article, we will discuss the definitions of malnutrition and emphasize its links with sarcopenia and frailty. We will show the relevance of frailty and sarcopenia in the course of liver diseases. The emerging role of muscle depletion on the cardiorespiratory system will also be highlighted. The importance of body composition will be demonstrated and the main tools reviewed. Finally, we adapted the definition of malnutrition to patients with cirrhosis based on the assessment of sarcopenia together with reduced food intakes.

Sarcopenia in Cirrhosis: Looking Beyond the Skeletal Muscle Loss to See the Systemic Disease

Sarcopenia is a common complication of cirrhosis and is defined as a progressive and generalized loss of skeletal muscle mass, strength, and function. Sarcopenia is associated with poor prognosis and increased mortality. How sarcopenia and muscle wasting relate to such poor outcomes requires looking beyond the overt muscle loss and at this entity as a systemic disease that affects muscles of vital organs including cardiac and respiratory muscles. This review explores the pathophysiological pathways and mechanisms that culminate in poor outcomes associated with sarcopenia. This provides a launching pad to identify potential targets for therapeutic intervention and optimization to improve patient outcomes.

Cardiovascular and Metabolic Consequences of Liver Transplantation: A Review

Liver transplantation (LT) is considered the curative treatment option for selected patients who suffer from end-stage or acute liver disease or hepatic malignancy (primary). After LT, patients should be carefully monitored for complications that may appear, partially due to immunosuppressive therapy, but not entirely. Cardiovascular diseases are frequently encountered in patients with LT, being responsible for high morbidity and mortality. Patients with underlying cardiovascular and metabolic pathologies are prone to complications after the transplant, but these complications can also appear de novo, mostly associated with immunosuppressants. Metabolic syndrome, defined by obesity, hypertension, dyslipidemia, and hyperglycemia, is diagnosed among LT recipients and is aggravated after LT, influencing the long-term survival. In this review, our purpose was to summarize the current knowledge regarding cardiovascular (CV) diseases and the metabolic syndrome associated with LT and to assess their impact on short and long-term morbidity and mortality.

Long-term impact of dialysis-requiring AKI during the perioperative period of liver transplantation on postdischarge outcomes

BACKGROUND

Patients undergoing liver transplantation (LT) are prone to dialysis-requiring acute kidney injury (AKI-D). However, long-term prognoses among them need further investigation, as overall survival after LT is improving.

METHODS

A nationwide, population-based cohort study was conducted using the data of Korean National Health Insurance System between 2006 and 2015. The patients who received dialysis during the perioperative period of LT were in the AKI-D group, and the control group included those who did not undergo dialysis.

RESULTS

Among the 6879 patients who underwent LT, 968 were in the AKI-D group. All-cause mortality [adjusted hazard ratio (HR): 1.52 (1.26-1.83), P < 0.001], end-stage renal disease (ESRD) progression [adjusted HR: 2.93 (2.34-3.66), P < 0.001], and ICU readmission [adjusted HR: 1.70 (1.44-2.01), P < 0.001] within and after 90 days from discharge were increased in the AKI-D group. When analyzed among those who recovered from dialysis at discharge, overall outcomes were similar to those of the AKI-D group, except the long-term mortality.

CONCLUSIONS

AKI-D during the perioperative period of LT was associated with worse mortality, ESRD progression, and ICU readmission risk. The results of renal-recovered patients could indicate clinicians that achievement of dialysis independence is important to gain favorable long-term postdischarge survival.

Renaissance of Modified Charlson Comorbidity Index in Prediction of Short- and Long-Term Survival After Liver Transplantation?

Background

Orthotopic liver transplantation (OLT) is the standard of care for end-stage liver disease. The Charlson Comorbidity Index (CCI) was originally created to assess the survival rate of patients with chronic diseases, although it was modified and adopted in OLT recipients as CCI-OLT.

Material/Methods

In total of 248 consecutive liver transplant recipients with viral cirrhosis in 98 (39.5%) patients were included. CCI-OLT was calculated assigning a weight of 3 to chronic obstructive pulmonary disease; weight of 2 to coronary artery disease, connective tissue disease, and renal insufficiency; and a weight of 1 to diabetes mellitus.

Results

CCI-OLT was significantly correlated with recipient age (p<0.001; R=0.333) and was a significant risk factor for early post-transplant mortality (p=0.004). The presence of diabetes mellitus significantly increased the odds of early mortality (p=0.010). The optimal cut-off for CCI-OLT in prediction of mortality during the first 90 days after transplantation was ≥1, with an AUROC of 0.780 (95% CI: 0.670–0.891; p<0.001). Increasing CCI-OLT was a significant risk factor for worse 5-year post-transplant survival (p=0.001), along with coronary artery disease (p=0.008) and diabetes mellitus (p=0.021). The optimal cut-off for prediction of 5-year mortality for CCI-OLT was ≥1, with the AUROC of 0.638 (95% CI: 0.544–0.733; p=0.004).

Conclusions

CCI-OLT is a useful tool for measuring the effect of pretransplant comorbidities and to stratify the effect of risk on both short- and long-term outcomes after OLT. Recipient age and diabetes strongly affected short-term survival after OLT, and metabolic and vascular complications were the leading causes of death at 5 years after OLT.

An update on cirrhotic cardiomyopathy

Cirrhosis with portal hypertension and related complications are associated with a high mortality. Excess of circulating vasodilators and cardiodepressive substances lead to a hyperdynamic circulation with changed myocardial structure and function. The entity cirrhotic cardiomyopathy seems to be involved in different aspects of hepatic decompensation, which focuses on new targets of treatment. Areas covered: This review deals with contemporary aspects of cirrhotic cardiomyopathy, and the literature search was undertaken by PubMed with 'cirrhotic' and 'cardiomyopathies' as MeSH Terms. Cirrhotic cardiomyopathy is defined as the presence of systolic and diastolic dysfunction and electrophysiological abnormalities. The diagnosis is based on contemporary Doppler/Echocardiography measurements or quantitative magnetic resonance imaging. Cirrhotic cardiomyopathy is independent of the etiology of the liver disease but related to severity and survival. Expert commentary: The outcome of invasive procedures and liver transplantation is influenced by the presence of cardiac dysfunction. Therefore, a cautious cardiac evaluation should be included in the patient evaluation prior to liver transplantation. Liver transplantation ameliorates most of the abnormalities seen in cirrhotic cardiomyopathy, but no specific treatment can yet be recommended.

Prediction of all-cause mortality after liver transplantation using left ventricular systolic and diastolic function assessment

Although pretransplant cardiac dysfunction is considered a major predictor of poor outcomes after liver transplantation (LT), the ability of left ventricular (LV) systolic/diastolic function (LVSF/LVDF), together or individually, to predict mortality after LT is poorly characterized. We retrospectively evaluated pretransplant clinical and Doppler echocardiographic data of 839 consecutive LT recipients from 2009 to 2012 aged 18–60 years. The primary endpoint was all-cause mortality at 4 years. The overall survival rate was 91.2%. In multivariate Cox analysis, reduced LV ejection fraction (LVEF, P = 0.014) and decreased transmitral E/A ratio(P = 0.022) remained significant prognosticators. In LVSF analysis, patients with LVEF≤60% (quartile [Q]1) had higher mortality than those with LVEF>60% (hazard ratio = 1.90, 95% confidence interval = 1.15–3.15, P = 0.012). In LVDF analysis, patients with an E/A ratio<0.9(Q1) had a 2.19-fold higher risk of death (95% confidence interval = 1.11–4.32, P = 0.024) than those with an E/A ratio>1.4(Q4). In combined LVDF and LVSF analysis, patients with an E/A ratio<0.9 and LVEF≤60% had poorer survival outcomes than patients with an E/A ratio≥0.9 and LVEF>60% (79.5% versus 93.3%, P = 0.001). Patients with an early mitral inflow velocity/annular velocity (E/e’ ratio)>11.5(Q4) and LV stroke volume index (LVSVI)<33mL/m²(Q1) showed worse survival than those with an E/e’ ratio≤11.5 and LVSVI ≥33mL/m²(78.4% versus 92.2%, P = 0.003). A combination of LVSF and LVDF is a better predictor of survival than LVSF or LVDF alone.

Heart Failure and Liver Disease: Cardiohepatic Interactions

Heart failure (HF) and liver disease often co-exist. This is because systemic disorders and diseases affect both organs (alcohol abuse, drugs, inflammation, autoimmunity, infections) and because of complex cardiohepatic interactions. The latter, which are the focus of this review, include the development of acute cardiogenic liver injury and congestive hepatopathy in HF as well as cardiac dysfunction and failure in the setting of liver cirrhosis, nonalcoholic fatty liver disease, and sequelae following liver transplantation. The emerging role of altered liver X receptor signaling in the pathogenesis of HF comorbidities as well as of the intestinal microbiome and its metabolites in HF and liver disease are fruitful areas for future research.

Evaluation of Liver Graft Recipient Workup in Predicting of Early Cardiovascular Events During Liver Transplantation: A Single-Center Experience

BACKGROUND

Cardiovascular events (CVE) contribute to serious complications and death after liver transplantation (LT). Troponin I (TnI) level >0.07 mg/L and prior cardiac disease are known to be the independent predictors for posttransplant CVE. We evaluated single-center cardiac workup to predict early cardiovascular morbidity and mortality after LT.

PATIENTS AND METHODS

We recruited 105 consecutive liver transplant recipients (male/female, 59/46; mean age, 51.66 ± 11.67 years). The cardiological assessment at evaluation for LT included medical history, electrocardiogram, echocardiography, Holter monitoring, and exercise test. We collected data regarding CVE including hypotonia with catecholamine usage, arrhythmia, sudden cardiac death, pulmonary edema, and myocardial infarction within 7 days after LT.

RESULTS

CVE during LT occurred in 42 recipients (40%) and after LT in 9 patients (8.57%). Proposed cutoff level of TnI >0.07 mg/L did not correlate with CVE during operation (P = .73) or after LT (P = .47). CVE during LT was associated with arterial hypertension in medical history (P <.001), right ventricular systolic pressure (P< .05), and clinical scores: Child-Pugh (P = .04), Model for End-Stage Liver Disease (MELD) (P = .04), MELD incorporating serum sodium (P<.03), and integrated MELD score (P = .01). CVE after LT correlated only with arrhythmia (P<.001) and catecholamine usage (P < .05) perioperatively. Of interest, catecholamine usage during LT was associated with prolonged stay at the intensive care unit (P < .05).

CONCLUSION

The single-center algorithm with noninvasive cardiac procedures without TnI assessment is optimal in evaluation before LT; however, medical history and severity of the liver disease are crucial for short-term cardiovascular morbidity after LT.

Cardiac Events Within the 30-Day Postoperative Period Is Associated With Increased 1-Year Mortality Among Deceased-Donor Liver Transplant Recipients

OBJECTIVES

Each year in the United States, approximately 40000 patients with a liver disorder will progress to end-stage liver disease and about 30000 of those patients will subsequently die from this condition. Liver transplant remains the definitive treatment option for end-stage liver disease, and understanding the causes of posttransplant mortality is an ongoing area of investigation.

MATERIALS AND METHODS

In this retrospective cohort study, patients who underwent orthotopic liver transplant between January 2012 and January 2015 at the Johns Hopkins Hospital Liver Transplant Program were reviewed by a single reviewer for cardiac events in the 30 days after transplant or during the index admission.

RESULTS

Of the 145 patients included, 30 (20.6%) were identified as having experienced a cardiac event during the defined postoperative period. Overall 1-year mortality for the cohort of 145 patients was 11.7%; however, 1-year mortality in those who had a cardiac event was 36.7% compared with 5.2% in the noncardiac event group (odds ratio = 18.17; P < .001). Although there was a statistically significant difference in age between the groups (58.6 vs 52.3 years old), once accounted for in multivariate analysis, a posttransplant cardiac event was still a statistically significant variable in 1-year mortality (odds ratio = 89.16; 95% confidence interval, 2.71-2933.95; P = .012). Similarly, hepatocellular carcinoma, sex, age, and presence of diabetes had little effect on 1-year mortality when we compared those patients who experienced a cardiac event in the first 30 days versus those who did not (odds ratio = 100.82; 95% confidence interval, 2.15-4726.12; P = .019).

CONCLUSIONS

Recipients who experience cardiac events within 30 days after transplant have increased 1-year posttransplant mortality. This highlights the importance of cardiac risk stratification before transplant.

Multidisciplinary approach to cardiac and pulmonary vascular disease risk assessment in liver transplantation: An evaluation of the evidence and consensus recommendations

Liver transplant (LT) candidates today are older, have greater medical severity of illness, and have more cardiovascular comorbidities than ever before. In addition, there are specific cardiovascular responses in cirrhosis that can be detrimental to the LT candidate. Cirrhotic cardiomyopathy, a condition characterized by increased cardiac output and a reduced ventricular response to stress, is present in up to 30% of patients with cirrhosis, thus challenging perioperative management. Current noninvasive tests that assess for subclinical coronary and myocardial disease have low sensitivity, and altered hemodynamics during the LT surgery can unmask latent cardiovascular disease either intraoperatively or in the immediate postoperative period. Therefore, this review, assembled by a group of multidisciplinary experts in the field and endorsed by the American Society of Transplantation Liver and Intestine and Thoracic and Critical Care Communities of Practice, provides a critical assessment of the diagnosis of cardiac and pulmonary vascular disease and interventions aimed at managing these conditions in LT candidates. Key points and practice-based recommendations for the diagnosis and management of cardiac and pulmonary vascular disease in this population are provided to offer guidance for clinicians and identify gaps in knowledge for future investigations.

Living Donor Liver Transplantation for Patients Older Than Age 70 Years: A Single-Center Experience

Over the past two decades, the age of liver transplantation (LT) recipients has been increasing. We reviewed our experience with LT for patients aged ≥70 years (range: 70-78 years) and investigated the feasibility of performing LT, especially living donor LT (LDLT), for older patients. We retrospectively reviewed the medical records of 25 patients (15 LDLT recipients, 10 deceased donor LT recipients) aged ≥70 years who underwent LT from January 2000 to April 2016. Their perioperative morbidity rate was 28.0%, and the in-hospital mortality rate was 16.0%; these results were comparable to those of matched patients in their 60s (n = 73; morbidity, p = 0.726; mortality, p = 0.816). For patients in their 70s, the 1- and 5-year patient survival rates were 84.0% and 69.8%, and the 1- and 5-year graft survival rates were 83.5% and 75.1%, respectively. Comparisons of patient and graft survival rates between matched patients in their 60s and 70s showed no statistically significant differences (patient survival, p = 0.372; graft survival, p = 0.183). Our experience suggests that patients aged ≥70 years should not be excluded from LT, or even LDLT, based solely on age and implies that careful selection of recipients and donors as well as meticulous surgical technique are necessary for successful results.

The role of autonomic dysfunction in predicting 1-year mortality after liver transplantation

BACKGROUND & AIMS

Model for end-stage liver disease (MELD) score has been extensively used to prioritize patients for liver transplantation and determine their prognosis, but with limited predictive value. Autonomic dysfunction may correlate with increased mortality after liver transplant. In this study, two autonomic biomarkers, complexity and deceleration capacity, were added to the predicting model for 1-year mortality after liver transplantation.

METHODS

In all, 30 patients with end-stage liver diseases awaiting liver transplantation were included. Complexity and deceleration capacity were calculated by multi-scale entropy and phase-rectified signal averaging, respectively. Different combinations of autonomic factors and MELD score were used to predict mortality rate of liver transplant after 1-year follow-up. Receiver-operating characteristics curve analysis was performed to determine clinical predictability. Area under the receiver-operating characteristics curve represents the overall accuracy.

RESULTS

The 1-year mortality rate was 16.7% (5/30). The overall accuracy of MELD score used for predicting mortality after liver transplantation was 0.752. By adding complexity and deceleration capacity into the predicting model, the accuracy increased to 0.912. Notably, the accuracy of the prediction using complexity and deceleration capacity alone was 0.912.

CONCLUSION

Complexity and deceleration capacity, which represent different dynamical properties of a human autonomic system, are critical factors for predicting mortality rate of liver transplantation. We recommend that these pre-operative autonomic factors may be helpful as critical adjuncts to predicting model of mortality rate in prioritizing organ allocation.

Pulmonary hypertension and cardiac hypertrophy in children recipients of orthotopic living related liver transplantation

Surgical stress, liberation of cytokines associated with re-perfusion injury, and long standing use of immune suppressive medications in children recipients of orthotopic living related liver transplantation (OLRLT) pose cardiovascular risk. Reported cardiovascular adverse effects vary from left ventricular wall thickening, hypertrophic cardiomyopathy to resting ECG abnormalities, asymptomatic ST depression following increased heart rate and ventricular arrhythmias. Twenty-five consecutive children recipients of OLRLT were assessed by conventional 2-D, M-mode echocardiography and Doppler. The mean age ± SD at transplantation and at enrollment in study was 6.3 ± 4.5 and 13.5 ± 5.6 years respectively. All children were on immunosuppressive medications, with tacrolimus being constant among all. Long-term post-transplant echocardiography revealed statistically significant interventricular septal hypertrophy among all (mean thickness 0.89 ± 0.16 cm), (P = 0.0001) in comparison to reference range for age, 24 had pulmonary hypertension (mean mPAP 36.43 ± 5.60 mm Hg, P = 0.0001), and early diastolic dysfunction with a mean Tei index of 0.40 ± 0.10. However cardiac function was generally preserved. Children recipients of OLRLT have cardiac structural and functional abnormalities that can be asymptomatic. Pulmonary hypertension, increased cardiac mass, de novo aortic stenosis and diastolic heart failure were among abnormalities encountered in the studied population. Echocardiography is indispensible in follow-up of children recipients of OLRLT.

The Circulatory System in Liver Disease

In the cirrhotic liver, distortion of the normal liver architecture is caused by structural and vascular changes. Portal hypertension is often associated with a hyperdynamic circulatory syndrome in which cardiac output and heart rate are increased and systemic vascular resistance is decreased. The release of several vasoactive substances is the primary factor involved in the reduction of mesenteric arterial resistance, resulting in sodium and water retention with eventual formation of ascites. Management of these patients with acute cardiac dysfunction often requires invasive hemodynamic monitoring in an intensive care unit setting to tailor decisions regarding use of fluids and vasopressors.

Coronary Computed Tomography Angiography in Combination with Coronary Artery Calcium Scoring for the Preoperative Cardiac Evaluation of Liver Transplant Recipients

Liver transplantation is the best treatment option for early-stage hepatocellular carcinoma, liver cirrhosis, fulminant liver failure, and end-stage liver diseases. Even though advances in surgical techniques and perioperative care have improved postoperative outcomes, perioperative cardiovascular complications are a leading cause of postoperative morbidity and mortality following liver transplantation. Ischemic coronary artery disease (CAD) and cardiomyopathy are the most common cardiovascular diseases and could be negative predictors of postoperative outcomes in liver transplant recipients. Therefore, comprehensive cardiovascular evaluations are required to assess perioperative risks and prevent concomitant cardiovascular complications that would preclude good outcomes in liver transplant recipients. The two major types of cardiac computed tomography are the coronary artery calcium score (CACS) and coronary computed tomography angiography (CCTA). CCTA in combination with the CACS is a validated noninvasive alternative to coronary angiography for diagnosing and grading the severity of CAD. A CACS > 400 is associated with significant CAD and a known important predictor of posttransplant cardiovascular complications in liver transplant recipients. In this review article, we discuss the usefulness, advantages, and disadvantages of CCTA combined with CACS as a noninvasive diagnostic tool for preoperative cardiac evaluation and for maximizing the perioperative outcomes of liver transplant recipients.

Impact of Cardiovascular Risk Factors on Long-Term Mortality After Liver Transplantation

Immunosuppression with calcineurin inhibitors has contributed to an increased prevalence of hypertension, diabetes, and hypercholesterolemia in patients receiving liver transplantation. This study evaluated the prevalence of cardiovascular risk factors, their management, and long-term mortality after liver transplantation. Medical records were reviewed in 333 adult patients who underwent orthotopic liver transplantation. Data were collected on medical diagnoses before and after transplantation, medication use, and on long-term mortality. The 333 patients in the study included 223 men and 110 women, mean age 59 ± 10 years. The mean follow-up was 50 ± 28 months. After transplantation, there was a high prevalence of hypertension (67%), hypercholesterolemia (46%), diabetes mellitus (42%), and chronic kidney disease (45%). Out of 333 patients in the study, 96 patients (29%) died during follow-up. Stepwise logistic regression was performed to identify the risk factors that might influence long-term mortality outcomes. Based on pretransplant characteristics, positive independent risk factors that increased mortality were age at transplant and hepatitis C. After transplantation, positive predictive factors were diabetes mellitus and cancer. A negative predictive risk factor for mortality was hypercholesterolemia. Analysis of medication after transplantation showed that positive predictive factors were the use of insulin, steroids, and antibiotics. Negative predictors for mortality were tacrolimus and mycophenolate. Our data suggest that diabetes mellitus and hepatitis C play an important role in worsening posttransplant mortality.

Myocardial injury in patients with hemodynamic derangements during and/or after liver transplantation

Myocardial injury, defined as an elevation of cardiac troponin (cTn) resulting from ischemia, is associated with substantial mortality in surgical patients, and its incidence, risk factors, and impact on patients undergoing liver transplantation (LT) are poorly understood. In this study, adult patients who experienced perioperative hemodynamic derangements and had cTn measurements within 30 days after LT between 2006 and 2013 were studied. Of 502 patients, 203 (40.4%) met the diagnostic criteria (cTn I ≥0.1 ng/mL) of myocardial injury. The majority of myocardial injury occurred within the first three postoperative days and presented without clinical signs or symptoms of myocardial infarction. Thirty-day mortality in patients with myocardial injury was 11.4%, significantly higher compared with that in patients without myocardial injury (3.4%, P<.01). Cox analysis indicated the peak cTn was significantly associated with 30-day mortality. Multivariable logistic analysis identified three independent risk factors: requirement of ventilation before transplant (odds ratios (OR) 1.6, P=.006), RBC≥15 units (OR 1.7, P=.006), and the presence of PRS (OR 2.0, P=.028). We concluded that post-LT myocardial injury in this high-risk population was common and associated with mortality. Our findings may be used in pretransplant stratification. Further studies to investigate this postoperative cardiac complication in all LT patients are warranted.