Validation of cardiovascular risk scores in a liver transplant population

Evaluation of recipients with significant comorbidity - Patients with cardiovascular disease

Liver transplant(ation) (LT) is the most effective treatment for patients with decompensated liver disease. The increasing prevalence of obesity and type 2 diabetes and the growing number of patients with non-alcoholic fatty liver disease being evaluated for LT, have resulted in a greater proportion of LT candidates presenting with a higher risk of cardiovascular disease. As cardiovascular disease is a major cause of morbidity and mortality after LT, a thorough cardiovascular evaluation pre-LT is crucial. In this review, we discuss the latest evidence on the cardiovascular evaluation of LT candidates and we focus on the most prevalent conditions, namely ischaemic heart disease, atrial fibrillation and other arrhythmias, valvular heart disease, and cardiomyopathies. LT candidates undergo an electrocardiogram, a resting transthoracic echocardiography and an assessment of their cardiopulmonary functional ability as part of their standardised pre-LT work-up. Further diagnostic work-up is undertaken based on the results of the baseline evaluation and may include a coronary computed tomography angiography in patients with cardiovascular risk factors. The evaluation of potential LT candidates for cardiovascular disease requires a multidisciplinary approach, with input from anaesthetists, cardiologists, hepatologists and transplant surgeons.

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.

The Role of Arterial Stiffness in the Estimation of Cardiovascular Risk in Liver Transplant Recipients

Background

Long-term cardiovascular (CV) events are a frequent cause of death and disability after liver transplant (LT). Although a more in-depth, risk-adapted control of CV risk factors may result in improved post-LT CV outcomes, an accurate stratification of the CV risk of LT recipients to better implement preventive strategies is lacking. Aortic pulse wave velocity (aPWV) is a surrogate of arterial stiffness that has been suggested as a biomarker of CV risk; it has never been evaluated in adult LT recipients.

Methods

In a single-center prospective study, we included 122 LT recipients at 12 (n = 39), 60 (n = 45), or 120 (n = 38) mo after LT. aPWV estimation by oscillometry, clinical assessment of CV risk factors, and CV risk estimation by standard clinical scores (systematic coronary risk evaluation and pooled cohort equation) were performed. The incidence of CV events during prospective follow-up was registered.

Results

aPWV was independently associated with age and the grade of control of blood pressure. After a median follow-up of 35 mo, 15 patients (12%) presented a CV event. Higher aPWV, diabetes, past or present smoking habit, previous CV events, lower eGFR, being in systematic coronary risk evaluation or pooled cohort equation high-risk groups, and higher levels of total cholesterol, LDL-cholesterol, creatinine, and triglycerides were associated with the incidence of CV events at univariate analysis; aPWV, past or present smoking habit, and triglycerides were independent predictors of CV events.

Conclusions

According to our results, aPWV mirrors CV risk in LT recipients and thus may be a useful CV risk biomarker in this population. Considering these preliminary results, its accuracy in stratifying risk requires confirmation in further studies.

Prognostic value of coronary risk factors, exercise capacity and single photon emission computed tomography in liver transplantation candidates: A 5-year follow-up study

BACKGROUND

Although consensus-based guidelines support noninvasive stress testing prior to orthotopic liver transplantation (OLT), the optimal screening strategy for assessment of coronary artery disease in patients with end-stage liver disease (ESLD) is unclear. This study sought to determine the relative predictive value of coronary risk factors, functional capacity, and single photon emission computed tomography (SPECT) on major adverse cardiovascular events and all-cause mortality in liver transplantation candidates.

METHODS

Prior to listing for transplantation, 404 consecutive ESLD patients were referred to a University hospital for cardiovascular (CV) risk stratification. All subjects met at least one of the following criteria: inability to perform > 4 METs by history (62%), insulin-treated diabetes mellitus (53%), serum creatinine > 1.72 mg/dL (8%), history of MI, PCI or CABG (5%), stable angina (3%), cerebrovascular disease (1%), peripheral vascular disease (1%). Subjects underwent Technetium-99m SPECT with multislice coronary artery calcium scoring (CACS) using exercise treadmill or standard adenosine stress in those unable to achieve 85% maximal heart rate (Siemens Symbia T16). Abnormal perfusion was defined as a summed stress score (SSS) ≥ 4.

RESULTS

Of the 404 patients, 158 (age 59 ± 9 years; male 68%) subsequently underwent transplantation and were included in the primary analysis. Of those, 50 (32%) died after a mean duration follow-up of 5.4 years (maximal 10.9 years). Most deaths (78%) were attributed to noncardiovascular causes (malignancy, sepsis, renal failure). Of the 32 subjects with abnormal perfusion (20%), nine (6%) had a high-risk perfusion abnormality defined as a total perfusion defect size (PDS) ≥ 15% and/or an ischemic PDS ≥ 10%. Kaplan-Meier survival curves demonstrated abnormal perfusion was associated with increased CV mortality (generalized Wilcoxon, P = 0.014) but not all-cause death. Subjects with both abnormal perfusion and an inability to exercise > 4 METs had the lowest survival from all-cause death (P = 0.038). Abnormal perfusion was a strong independent predictor of CV death (adjusted HR 4.2; 95% CI 1.4 to 12.3; P = 0.019) and MACE (adjusted HR 7.7; 95% CI 1.4 to 42.4; P = 0.018) in a multivariate Cox regression model that included age, sex, diabetes, smoking and the ability to exercise > 4 METs. There was no association between CACS and the extent of perfusion abnormality, nor with outcomes.

CONCLUSIONS

Most deaths following OLT are noncardiovascular. Nonetheless, abnormal perfusion is prevalent in this high-risk population and a stronger predictor of cardiovascular morbidity and mortality than functional status. A combined assessment of functional status and myocardial perfusion identifies those at highest risk of all-cause death. (Exercise Capacity and Single Photon Emission Computed Tomography in Liver Transplantation Candidates [ExSPECT]; ClinicalTrials.gov Identifier: NCT03864497).

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.

Metabolic Disorders After Liver Transplantation

Early after surgery, liver transplant (LT) recipients often develop weight gain due to an increase of caloric intake and fat mass (without recovery of muscle frame). This modification of body composition together with a negative metabolic impact of immunosuppressive drugs leads to a high prevalence of all the main metabolic disorders. Indeed, as expected, transplanted patients show a higher cardiovascular risk in comparison with general population. Notably, seeing the increase of mean age of transplanted population, metabolic disorders represent the true challenge for the transplant community. Considering the lack of evidences or clear indications about prevention, early diagnosis and treatment of metabolic disorders after LT, it would be mandatory to develop targeted further studies on this matter.

Bariatric Surgery Outcomes in Patients with Previous Organ Transplant: Scoping Review and Analysis of the MBSAQIP

BACKGROUND

Obesity is a major risk factor for transplant. Laparoscopic bariatric surgery (LBS) offers transplant patient benefits including improved comorbidities, graft function, and longevity. We completed a scoping review and analyzed the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) to determine the risk-benefit profile of LBS after transplant. We also compared laparoscopic sleeve gastrectomy (LSG) to laparoscopic Roux-en-Y gastric bypass (LRYGB) following transplant.

METHODS

Univariate analysis determined between group differences with subgroup analysis comparing LSG versus LRYGB in transplant patients. Multivariable analysis assessed whether prior transplant was independently associated with major complications or mortality.

RESULTS

A total of 469 (0.1%) patients had previous transplant and had more comorbidities and more often underwent LSG. Operative time (93.9 min vs 83 min, p < 0.001) and length of stay were longer. Major complications were threefold higher in patients with a transplant history (9.6% vs 3.2%; p < 0.001. Previous transplant was the second greatest independent predictor for major complication (OR 2.14 [1.54-2.98], p = < 0.001) but was not predictive of death (OR 1.06 [0.14-8.13] p = 0.956). Amongst transplant patients, LRYGB demonstrated higher rates of leak (n = 1), VTE, AKI, unplanned intubation, and readmission.

CONCLUSIONS

The 30-day complication rate from LBS is three times higher amongst patients with a transplant. LSG is likely the best surgical approach. Despite risks, post-transplant patients incur important benefits from LBS. Surgeons must be aware of this risk-benefit profile when determining LBS candidacy.

Incidence, Predictors, and Impact on Survival of Long-term Cardiovascular Events After Liver Transplantation

BACKGROUND

Information on the risk factors, particularly kidney function, and impact of long-term cardiovascular events (CVE) after liver transplantation (LT) remains scarce.

METHODS

This is a retrospective, single-center study that included consecutive LT recipients between 2007 and 2017. The incidence of CVE, their risk factors, and their impact on patient survival were investigated.

RESULTS

We included 627 LT recipients. The incidence of CVE was 8% and 20% at 12 and 60 months after LT, respectively. The independent risk factors of long-term (beyond 12 mo) CVE were age at LT (hazard ratio [HR], 1.04; 95% confidence interval [CI], 1.01-1.07), male gender (HR, 2.48; 95% CI, 1.21-5.05), history of pre-LT cardiovascular disease (HR, 2.19; 95% CI, 1.2-3.98), and immunosuppression with cyclosporine A (HR, 1.93; 95% CI, 1.14-3.3). In patients with pre-LT cardiovascular disease, creatinine levels 12 months after LT significantly impacted the risk of long-term CVE. Long-term CVE (HR, 2.12; 95% CI, 1.24-3.61), hepatitis C as the etiology of liver disease (HR, 2.18; 95% CI, 1.29-3.67), cytomegalovirus infection (HR, 1.89; 95% CI, 1.08-3.3), and donor age (HR, 1.02; 95% CI, 1.01-1.04) were independent factors associated with post-LT patient death.

CONCLUSIONS

Age, male gender, cardiovascular disease before LT, and cyclosporine A were associated with the risk of long-term CVE. The impact of serum creatinine was restricted to patients with pre-LT cardiovascular disease. In these patients, preservation of kidney function early after LT may lessen the incidence of CVE, which are an independent predictor of post-LT death.

Pre-transplant diabetes predicts atherosclerotic vascular events and cardiovascular mortality in liver transplant recipients: a long-term follow-up study

Background Early after surgery, liver transplant (LT) recipients often develop weight gain. Metabolic disorders and cardiovascular disease represent main drivers of morbidity and mortality. Our aim was to identify predictors of atherosclerotic vascular events (AVE) and to assess the impact of AVE on the long-term outcome. Methods We retrospectively analyzed data from patients transplanted between 2000 and 2005 and followed-up in five Italian transplant clinics. Cox Regression analysis was performed to identify predictors of AVE, global mortality, and cardiovascular mortality. Survival analysis was performed using the Kaplan-Meier method. Results We analyzed data from 367 subjects during a median follow-up of 14 years. Thirty-seven post-LT AVE were registered. Patients with AVE more frequently showed pre-LT diabetes mellitus (DM) (48.6 vs 13.9%, p=0.000). In the post-LT period, patients with AVE satisfied criteria of metabolic syndrome in 83.8% vs. 36.7% of subjects without AVE (p=0.000). At multivariate analysis, pre-LT DM independently predicted AVE (HR 2.250, CI 4.848-10.440, p=0.038). Moreover, both pre-LT DM and AVE strongly predicted cardiovascular mortality (HR 5.418, CI 1.060-29.183, p=0.049, and HR 86.097, CI 9.510-779.480, p=0.000, respectively). Conclusions Pre-LT DM is the main risk factor for post-LT AVE. Pre-LT DM and post-LT AVE are strong, long-term predictors of cardiovascular mortality. Patients with pre-LT DM should obtain a personalized follow-up for prevention or early diagnosis of AVE.

Understanding and managing cardiovascular outcomes in liver transplant recipients

PURPOSE OF REVIEW

Cardiovascular disease (CVD) is a common cause of mortality after liver transplantation. The transplant community is focused on improving long-term survival. Understanding the prevalence of CVD in liver transplant recipients, precipitating factors as well as prevention and management strategies is essential to achieving this goal.

RECENT FINDINGS

CVD is the leading cause of death within the first year after transplant. Arrhythmia and heart failure are the most often cardiovascular morbidities in the first year after transplant which could be related to pretransplant diastolic dysfunction. Pretransplant diastolic dysfunction is reflective of presence of cirrhotic cardiomyopathy which is not as harmless as it was thought. Multiple cardiovascular risk prediction models have become available to aid management in liver transplant recipients.

SUMMARY

A comprehensive prevention and treatment strategy is critical to minimize cardiovascular morbidity and mortality after liver transplant. Weight management and metabolic syndrome control are cornerstones to any prevention and management strategy. Bariatric surgery is an underutilized tool in liver transplant recipients. Awareness of 'metabolic-friendly' immunosuppressive regimens should be sought. Strict adherence to the cardiology and endocrine society guidelines with regard to managing metabolic derangements post liver transplantation is instrumental for CVD prevention until transplant specific recommendations can be made.

Nonalcoholic Fatty Liver Disease: Epidemiology, Liver Transplantation Trends and Outcomes, and Risk of Recurrent Disease in the Graft

In parallel with the rising prevalence of metabolic syndrome globally, nonalcoholic fatty liver (NAFL) disease is the most common chronic liver disease in Western countries and nonalcoholic steatohepatitis (NASH) has become increasingly associated with hepatocellular carcinoma. Recent studies have identified NASH as the most rapidly growing indication for liver transplantation (LT). As a hepatic manifestation of the metabolic syndrome, NAFL disease can be histologically divided into NAFL and NASH. NAFL is considered a benign condition, with histological changes of hepatocyte steatosis but without evidence of hepatocellular injury or fibrosis. This is distinct from NASH, which is characterized by hepatocyte ballooning and inflammation, and which can progress to fibrosis and cirrhosis, hepatocellular carcinoma, and liver failure. As for any other end-stage liver disease, LT is a curative option for NASH after the onset of decompensated cirrhosis or hepatocellular carcinoma. Although some studies have suggested increased rates of sepsis and cardiovascular complications in the immediate postoperative period, the long-term posttransplant survival of NASH cases is similar to other indications for LT. Recurrence of NAFL following LT is common and can be challenging, although recurrence rates of NASH are lower. The persistence or progression of metabolic syndrome components after LT are likely responsible for NASH recurrence in transplanted liver. Therefore, while maintaining access to LT is important, concerted effort to address the modifiable risk factors and develop effective screening strategies to identify early stages of disease are paramount to effectively tackle this growing epidemic.

A point-based prediction model for cardiovascular risk in orthotopic liver transplantation: The CAR-OLT score

Cardiovascular disease (CVD) complications are important causes of morbidity and mortality after orthotopic liver transplantation (OLT). There is currently no preoperative risk-assessment tool that allows physicians to estimate the risk for CVD events following OLT. We sought to develop a point-based prediction model (risk score) for CVD complications after OLT, the Cardiovascular Risk in Orthotopic Liver Transplantation risk score, among a cohort of 1,024 consecutive patients aged 18-75 years who underwent first OLT in a tertiary-care teaching hospital (2002-2011). The main outcome measures were major 1-year CVD complications, defined as death from a CVD cause or hospitalization for a major CVD event (myocardial infarction, revascularization, heart failure, atrial fibrillation, cardiac arrest, pulmonary embolism, and/or stroke). The bootstrap method yielded bias-corrected 95% confidence intervals for the regression coefficients of the final model. Among 1,024 first OLT recipients, major CVD complications occurred in 329 (32.1%). Variables selected for inclusion in the model (using model optimization strategies) included preoperative recipient age, sex, race, employment status, education status, history of hepatocellular carcinoma, diabetes, heart failure, atrial fibrillation, pulmonary or systemic hypertension, and respiratory failure. The discriminative performance of the point-based score (C statistic = 0.78, bias-corrected C statistic = 0.77) was superior to other published risk models for postoperative CVD morbidity and mortality, and it had appropriate calibration (Hosmer-Lemeshow P = 0.33).

CONCLUSION

The point-based risk score can identify patients at risk for CVD complications after OLT surgery (available at www.carolt.us); this score may be useful for identification of candidates for further risk stratification or other management strategies to improve CVD outcomes after OLT. (Hepatology 2017;66:1968-1979).

Incidence of and Risk Assessment for Adverse Cardiovascular Outcomes After Liver Transplantation: A Systematic Review

BACKGROUND

Cardiovascular events represent a major source of morbidity and mortality after liver transplantation and will likely increase given the aging population and nonalcoholic fatty liver disease as a leading indication for transplant. The optimal cardiovascular risk stratification approach in this evolving patient population remains unclear. The aims of this systematic review are to: (1) refine the definition, (2) characterize the incidence, and (3) identify risk factors for cardiovascular events post-liver transplantation. Additionally, we evaluated performance characteristics of different cardiac testing modalities.

METHODS

MEDLINE via PubMed, EMBASE, Web of Science, and Scopus were searched for studies published between 2002 and 2016 (model of end-stage liver disease era). Two authors independently reviewed articles to select eligible studies and performed data abstraction.

RESULTS

Twenty-nine studies representing 57 493 patients from 26 unique cohorts were included. Definitions of cardiovascular outcomes were highly inconsistent. Incidence rates were widely variable: 1% to 41% for outcomes of 6 months or shorter and 0% to 31% for outcomes longer than 6 months. Multivariate analyses demonstrated that older age and history of cardiac disease were the most consistent predictors of cardiovascular events posttransplant (significant in 8/23 and 7/22, studies, respectively). Predictive capacity of various cardiac imaging modalities was also discrepant.

CONCLUSIONS

The true incidence of cardiovascular outcomes post-liver transplant remains unknown in large part due to lack of consensus regarding outcome definition. Overall, poor data quality and gaps in knowledge limit the ability to clearly identify predictors of outcomes, but existing data support a more aggressive risk stratification protocol for patients of advanced age and/or with preexisting cardiac disease.

The post-transplant course of patients undergoing liver transplantation for nonalcoholic steatohepatitis versus cryptogenic cirrhosis: a retrospective case-control study

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) can be considered the hepatic manifestation of the metabolic syndrome with nonalcoholic steatohepatitis (NASH) as its progressive form. With increasing prevalence of the metabolic syndrome, NASH cirrhosis is becoming a leading cause for liver transplantation. Some cases of orthotopic liver transplantation (OLT) due to cryptogenic cirrhosis (CC) might show typical features of NASH cirrhosis. Therefore, our aim was to assess recurrence of liver fibrosis in patients transplanted for NASH versus CC after OLT.

PATIENTS AND METHODS

Patients transplanted for CC or NASH between 1 January 2004 and 30 September 2015 were included. The histological NAFLD activity score and the NAFLD fibrosis score (NFS) were assessed.

RESULTS

In total, 15 and 12 patients underwent OLT because of NASH and CC, respectively. The case load for OLT because of NASH was constantly increasing (n=2 in 2004-2007 vs. n=9 in 2012-2015) whereas decreasing for CC (n=6 in 2004-2007 vs. n=2 in 2012-2015). Patient characteristics at OLT were similar, except for an older age and a higher BMI in NASH patients (59.1±2.2 vs. 51.8±2.9 years, P=0.05; 27.7±1.2 vs. 24.3±0.8 kg/m, P=0.035). Although post-OLT plasma lipid levels and incidence of de-novo hypertension, diabetes, and hyperlipidemia were similar between groups, the post-transplant NFS re-increased in the NASH group (but not in the CC: -0.1317 vs. -1.3645 at 12 months post-OLT, P=0.0400). Post-transplant survival was similar in NASH and CC patients.

CONCLUSION

According to the NFS, some NASH patients show recurrence of fibrosis as early as 6-12 months after OLT.

Perioperative Cardiovascular Evaluation for Orthotopic Liver Transplantation

Patients with advanced liver disease have a high prevalence of cardiovascular risk factors, but many of them are asymptomatic. Cardiovascular risk stratification prior to liver transplant can be done by dobutamine stress echocardiography, stress myocardial perfusion imaging, cardiac computer tomography, and coronary angiography, but there are no clear recommendations regarding what method should be used and who should be screened. Because of this and because of inherent risk profile in this population, the variations in practice are significant. Careful screening and rigorous management of cardiovascular risk factors are important to ensure optimal cardiovascular outcomes in the immediate post-transplantation period and in the long term as well.

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.

Non-alcoholic fatty liver disease and liver transplantation

Cirrhosis secondary to non-alcoholic steatohepatitis (NASH) is a common indication for liver transplant. In comparison to other cirrhotic patients, patients with NASH cirrhosis are more likely to be older and have the metabolic syndrome. Pre-transplant, patients require careful evaluation of cardiovascular risk. As the incidence of non-alcoholic fatty liver disease (NAFLD) is rising, a greater proportion of donor grafts have steatosis greater than 30%, which is associated with poor outcomes. Grafts with steatosis greater than 60% are unsuitable for transplant. Overall, post-transplant survival outcomes for patients with NASH cirrhosis are similar to those with cirrhosis without NASH. However, NASH cirrhosis is associated with a higher 30-day mortality, predominantly from an increase in cardiovascular events and infections. Following liver transplant, there is a significant risk of NASH recurrence, although this seldom results in allograft loss. Furthermore, a significant number of patients who had a liver transplant for other reasons develop NASH de novo. When patients with NASH cirrhosis are considered for transplant, one of the major challenges lies in identifying which patients are too high risk for surgery. This review aims to provide information to aid this decision making process, and to provide guidance on the peri-operative care strategies that can modify risk.

Prevalence and factors associated with dyslipidemia after liver transplantation

OBJECTIVE

to determine the prevalence of abnormal total cholesterol (TC), low density lipoprotein (LDL), high density lipoprotein (HDL) and triglycerides in patients undergoing liver transplantation (LTx) and to identify predictors of these disorders.

METHODS

cross-sectional study to assess the prevalence of dyslipidemia in patients undergoing LTx. Demographic, socioeconomic, clinical, anthropometric and dietetic data were collected to determine the association with dyslipidemia using univariate and multivariate statistical analysis.

RESULTS

136 patients were evaluated, 68.1% of which had at least one type of dyslipidemia. The triglyceride level was high in 32.4% of cases, with low HDL in 49.3% of patients and high LDL levels in only 8.8%. High total cholesterol was observed in 16.2% of the study population and was associated with the recommendation for transplantation due to ethanolic cirrhosis (OR = 2.7) and a greater number of hours slept per night (OR = 1.5).

CONCLUSION

many patients presented dyslipidemia after transplantation, demonstrating the need for interventions in relation to modifiable factors associated with dyslipidemias that can mitigate or prevent these disorders.

Cardiovascular risk 10 years after liver transplant

OBJECTIVES

We sought to evaluate the frequency of cardiovascular risk factors in a cohort of patients 10 years after a liver transplant, and to assess their 10-year risk of fatal cardiovascular disease using Systematic COronary Risk Evaluation (SCORE) charts.

MATERIALS AND METHODS

Between January 1990 and June 1996, one hundred eighty-nine adults underwent a first liver transplant in our center. Fifty-nine patients (31%) died before reaching their tenth year, and 115 patients were available with complete clinical data at 10 years.

RESULTS

The main indications for liver transplant were alcoholic (38%) and viral cirrhosis (40%). The median age of patients was 56 (range, 29-73 y), 80% were men, 23% were obese, 16% were active smokers, 18% were diabetic, 40% had hypercholesterolemia, and 77% had hypertension. Before the tenth year after transplant, 6 deaths were because of cardiovascular diseases, which represents the third cause of late death (> 1 year after liver transplant). After liver transplant, 5% of the surviving patients underwent ischemic cardiovascular events during the first decade. At a 10-year assessment, the median estimated 10-year risk of fatal cardiovascular disease was 1% (range, 0%-9%) and 10% of the patients had a high risk (ie, SCORE ≥ 5%).

CONCLUSIONS

Our results suggest that the frequency of cardiovascular events is relatively low after a liver transplant, even if most of the patients had 1 or more cardiovascular risk factors. Nevertheless, clinicians should perform a similar evaluation 15 or 20 years after the liver transplant because cardiovascular risk exponentially increases with age.

mTOR inhibitors and dyslipidemia in transplant recipients: a cause for concern?

Post-transplant dyslipidemia is exacerbated by mammalian target of rapamycin (mTOR) inhibitors. Early clinical trials of mTOR inhibitors used fixed dosing with no concomitant reduction in calcineurin inhibitor (CNI) exposure, leading to concerns when consistent and marked dyslipidemia was observed. With use of modern concentration-controlled mTOR inhibitor regimens within CNI-free or reduced-exposure CNI regimens, however, the dyslipidemic effect persists but is less pronounced. Typically, total cholesterol levels are at the upper end of normal, or indicate borderline risk, in kidney and liver transplant recipients, and are lower in heart transplant patients under near-universal statin therapy. Of note, it is possible that mTOR inhibitors may offer a cardioprotective effect. Experimental evidence for delayed progression of atherosclerosis is consistent with evidence from heart transplantation that coronary artery intimal thickening and the incidence of cardiac allograft vasculopathy are reduced with everolimus versus cyclosporine therapy. Preliminary data also indicate that mTOR inhibitors may improve arterial stiffness, a predictor of cardiovascular events, and may reduce ventricular remodeling and decrease left ventricular mass through an anti-fibrotic effect. Post-transplant dyslipidemia under mTOR inhibitor therapy should be monitored and managed closely, but unless unresponsive to therapy should not be regarded as a barrier to its use.

Pre-and-post transplant considerations in patients with nonalcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is currently the third most common indication for liver transplantation in the United States. With the growing incidence of obesity, NAFLD is expected to become the most common indication for liver transplantation over the next few decades. As the number of patients who have undergone transplantation for NAFLD increases, unique challenges have emerged in the management and long-term outcomes in patients. Risk factors such as obesity, hypertension, diabetes, and hyperlipidemia continue to play an important role in the pathogenesis of the disease and its recurrence. Patients who undergo liver transplantation for NAFLD have similar long-term survival as patients who undergo liver transplantation for other indications. Research shows that post-transplantation recurrence of NAFLD is commonplace with some patients progressing to recurrent non-alcoholic steatohepatitis and cirrhosis. While treatment of comorbidities is important, there is no consensus on the management of modifiable risk factors or the role of pharmacotherapy and immunosuppression in patients who develop recurrent or de novo NAFLD post-transplant. This review provides an outline of NAFLD as indication for liver transplantation with a focus on the epidemiology, pathophysiology and risk factors associated with this disease. It also provides a brief review on the pre-transplant considerations and post-transplant factors including patient characteristics, role of obesity and metabolic syndrome, recurrence and de novo NAFLD, outcomes post-liver transplantation, choice of medications, and options for immunosuppression.

Twenty-year longitudinal follow-up after orthotopic liver transplantation: a single-center experience of 313 consecutive cases

With excellent short-term survival in liver transplantation (LT), we now focus on long-term outcome and report the first European single-center 20-year survival data. Three hundred thirty-seven LT were performed in 313 patients (09/88-12/92). Impact on long-term outcome was studied and a comparison to life expectancy of matched normal population was performed. A detailed analysis of 20-years follow-up concerning overweight (HBMI), hypertension (HTN), diabetes (HGL), hyperlipidemia (HLIP) and moderately or severely impaired renal function (MIRF, SIRF) is presented. Patient and graft survival at 1, 10, 20 years were 88.4%, 72.7%, 52.5% and 83.7%, 64.7% and 46.6%, respectively. Excluding 1-year mortality, survival in the elderly LT recipients was similar to normal population. Primary indication (p < 0.001), age (p < 0.001), gender (p = 0.017), impaired renal function at 6 months (p < 0.001) and retransplantation (p = 0.034) had significant impact on patient survival. Recurrent disease (21.3%), infection (20.6%) and de novo malignancy (19.9%) were the most common causes of death. Prevalence of HTN (57.3-85.2%, p < 0.001), MIRF (41.8-55.2%, p = 0.01) and HBMI (33.2-45%, p = 0.014) increased throughout follow-up, while prevalence of HLIP (78.0-47.6%, p < 0.001) declined. LT has conquered many barriers to achieve these outstanding long-term results. However, much work is needed to combat recurrent disease and side effects of immunosuppression (IS).

Long-term outcome of 'long-term liver transplant survivors'

There are few studies focusing on long-term complications in liver transplant (LT) recipients. The aim of this study was to define the outcome of LT recipients having survived at least 10 years from LT. Of 323 adult LT done between 1991 and 1997, the 167(52%) alive >10 years post-LT (baseline time) formed the study population. Long-term outcome measures included the following: immunosuppression, metabolic complications [obesity, arterial hypertension (AH), diabetes, dislypidemia], cardiovascular events (CVE), chronic renal dysfunction-CRD, and de novo tumors. Median age at LT was 50 years. Most common indication was postnecrotic cirrhosis (89%), mostly because of HCV (46%). At study-baseline (10 years post-LT), 29% were obese and AH, diabetes, dislypidemia, and CRD were present in 75%, 30%, 42%, and 36%, respectively. In most cases, these complications were already present 1 year post-LT; less than one quarter developed them onward. The 6 year cumulative survival since baseline reached 84% (n = 24 deaths), with most deaths related to recurrent graft diseases (mostly HCV) followed by de novo tumors or CVE. 1, 3, 5 and 10 years cumulative rates of CVE and de novo tumors since baseline were 2%, 5%, 10% and 17%, and 1%, 3%, 6% and 13%, respectively. Chronic renal impairment was independently associated with survival and development of CVE since baseline. The medium-term survival of 'long-term survivors', i.e. patients alive 10 years after LT is good, but metabolic complications and CRD are common and continue to increase afterwards. Cardiovascular events and de novo tumors increase gradually over time and represent a major cause of late mortality.

Nonalcoholic fatty liver disease following liver transplantation

Post-transplant, nonalcoholic hepatic steatosis and steatohepatitis are increasingly recognized as a complication of liver transplantation, and the progression of the latter through fibrosis to cirrhosis has been clearly shown. Non-alcoholic steatohepatitis (NASH) is independently associated with an increased risk of death from cardiovascular and liver diseases. While optimal therapy is not yet available in the post-liver transplant setting, knowledge gained in the therapy of NASH in the non-transplant setting can be used to design therapeutic interventions. In addition, early recognition with protocol liver biopsies and an effective preventive strategy by modifying known risk factors implicated in the recurrence of NASH would be the most effective way to curtail the progression of NASH before an effective treatment can be found. Additional rigorous research aimed at elucidating the pathogenesis, natural history, and selection of immunosuppressants for NASH is clearly warranted.

Liver transplantation for nonalcoholic steatohepatitis: the new epidemic

OBJECTIVE

To analyze incidence, outcomes, and utilization of health care resources in liver transplantation (LT) for nonalcoholic steatohepatitis (NASH).

SUMMARY OF BACKGROUND DATA

With the epidemic of obesity and metabolic syndrome in nearly 33% of the US population, NASH is projected to become the leading indication for LT in the next several years. Data on predictors of outcome and utilization of health care resources after LT in NASH is limited.

METHODS

We conducted an analysis from our prospective database of 144 adult NASH patients who underwent LT between December 1993 and August 2011. Outcomes and resource utilization were compared with other common indications for LT. Independent predictors of graft and patient survival were identified.

RESULTS

The average Model for End-Stage Liver Disease score was 33. The frequency of NASH as the primary indication for LT increased from 3% in 2002 to 19% in 2011 to become the second most common indication for LT at our center behind hepatitis C. NASH patients had significantly longer operative times (402 vs 322 minutes; P < 0.001), operative blood loss (18 vs 14 packed red blood cell units; P = 0.001), and posttransplant length of stay (35 vs 29 days; P = 0.032), but 1-, 3-, and 5-year graft (81%, 71%, 63%) and patient (84%, 75%, 70%) survival were comparable with other diagnoses. Age greater than 55 years, pretransplant intubation, dialysis, hospitalization, presence of hepatocellular carcinoma on explant, donor age greater than 55 years, and cold ischemia time greater than 550 minutes were significant independent predictors of survival for all patients, whereas body mass index greater than 35 was a predictor in NASH patients only.

CONCLUSIONS

We report the largest single institution experience of LT for NASH. Over a 10-year period, the frequency of LT for NASH has increased 5-fold. Although outcomes are comparable with LT for other indications, health care resources are stressed significantly by this new and increasing group of transplant candidates.

Is liver transplantation a risk factor for cardiovascular disease? A meta-analysis of observational studies

Up to two-thirds of patients develop metabolic syndrome within the first 5 years after orthotopic liver transplantation (OLT). However, data on overall cardiovascular (CV) morbidity and mortality among OLT recipients and particularly those who develop metabolic syndrome remain elusive. A literature search using MEDLINE, the Cochrane Central Register of Controlled Trials, the Cochrane Database of Systematic Reviews, and meeting abstracts (along with their bibliographies) was performed to identify studies. Data on ischemic CV events were extracted from each study and were used for pooled analyses. Overall pooled estimates and 95% confidence intervals (CIs) for the incidence of CV events and deaths were obtained with a random effects model. Twelve observational studies reporting CV outcomes for 4792 post-OLT recipients who were followed for 28,783 person-years were included. Pooled estimates showed that the 10-year risk of developing CV events among the post-OLT recipients was 13.6% (95% CI = 9%-8.1%). Pooled estimates from case-control studies showed that the post-OLT group had an approximately 64% greater risk of experiencing CV events than controls (standardized incidence ratio = 1.64, 95% CI = 1.18-2.20). Among OLT recipients, those with metabolic syndrome were approximately 4 times more likely to have a CV event [odds ratio (OR) = 4.01, 95% CI = 1.94-8.32] without any significant increase in all-cause mortality (OR = 1.15, 95% CI = 0.63-2.10). In conclusion, this systematic review suggests that OLT recipients and particularly those with metabolic syndrome have a high risk for CV events. However, the literature is limited and lacks high-quality studies. Future prospective studies are warranted to confirm these findings and determine whether aggressive risk-reduction strategies can attenuate the increased CV risk seen in this population.

Steroid elimination within 24 hours after orthotopic liver transplantation: effectiveness and tolerability

BACKGROUND

Steroids have been the mainstay of immunosuppressive regimen in liver transplantation. However, the use of steroids is associated with various post-transplant complications. This study evaluated the efficacy and safety of reduced immunosuppressive regimen with steroids (steroid elimination within 24 hours post-transplant) in a cohort of Chinese liver transplant recipients.

METHODS

Seventy-six patients in line with the selection criteria were enrolled in this prospective study. All patients received anti-IL-2 receptor antibody induction and tacrolimus-based maintenance therapy. The recipients were divided into two groups according to the duration of steroid use: 40 transplant in a 3-month withdrawal group and the remaining 36 in a 24-hour elimination group. Recipient survival, post-operative infections, biopsy-proven acute rejection and steroid-resistant acute rejection, non-healing wound, recurrence of hepatitis B virus (HBV) and hepatocellular carcinoma (HCC), de novo diabetes, hyperlipidemia and hypertension were assessed in the two groups.

RESULTS

There was no significant difference in patient survival, incidence of acute rejection episodes and hyperlipidemia, and recurrence of HBV and HCC between the two groups. However, the incidence rates of post-transplant infection, non-healing wound, de novo diabetes and hypertension were significantly lower in the 24-hour elimination group than in the 3-month withdrawal group (all P values <0.05).

CONCLUSION

Under anti-IL-2 receptor antibody induction and tacrolimus-based maintainance, steroid elimination within 24 hours post-transplant is associated with reduced steroid-related complications without increasing the risk of rejection.

Short-term cardiac and noncardiac mortality following liver transplantation

Objectives. To determine the importance of acute cardiac events as a cause of mortality compared to non-cardiac events in the four month period following liver transplantation (LT) using current preoperative cardiac screening strategies. Patients and Methods. We retrospectively reviewed timing, type, and outcome of adverse cardiac events, and all cause mortality in the 4 month postoperative period in 393 consecutive LT patients from October 1999 to February 2008. Results. Of 30 total deaths (7.6% overall mortality rate), 27 (90%) were due to surgical or medical complications and 3 (10%) were primary cardiac deaths (0.8% cardiac mortality rate). Acute cardiac events occurred in 26 patients (6.6%), including 13 arrhythmias (50%), 7 new onset heart failures (27%), and 6 myocardial infarctions (23%). Twelve of 13 intraoperative events were arrhythmias (92%) including two of three cardiac deaths. Conclusions. Using current preoperative screening recommendations, deaths from primary cardiac events within four months of LT are very uncommon (0.8%), especially compared with deaths related to medical and surgical complications (6.9%).

Coronary artery disease in orthotopic liver transplantation: pretransplant assessment and management

The prevalence of coronary artery disease in end-stage liver disease is only now being recognized. Liver transplant patients are a high risk subgroup for coronary artery disease, even if asymptomatic. Coronary artery disease is a predictor of poor outcomes; therefore, identification of those at risk must be a key clinical priority. However, risk assessment is particularly difficult as many of the available diagnostic tools have either proven to be unhelpful or remain to be validated. Risk factor profiling has been unable to identify those at risk and commonly underestimates risk. The high negative predictive value of Dobutamine stress echo, when target heart rates are achieved, allows it to be used to identify a low risk group. For all other patients, proceeding to invasive coronary angiography is often necessary, and the risks of the procedure can be reduced by a transradial approach. Pharmacological reduction of the consequences of coronary artery disease can be limited by the underlying liver disease. Revascularization pre-transplantation is recommended in international guidelines but has demonstrated little evidence of benefit. Surgical revascularization carries an increased risk in these patients and is commonly performed pre-transplantation, although combined liver and cardiac surgery has been described. Percutaneous coronary intervention is increasingly used with patients requiring anti-platelet medication for up to one year after intervention. We present a review of all these issues and the evidence for assessing and managing these high-risk patients.

Posttransplant metabolic syndrome: an epidemic waiting to happen

With increasing survival after orthotopic liver transplantation (OLT), metabolic syndrome and its individual components, including diabetes mellitus, hypertension, dyslipidemia, and obesity, are increasingly being identified and contributing to cardiovascular complications and late morbidity and mortality. The prevalence of posttransplant metabolic syndrome (PTMS) and its individual components has been found to be higher post-OLT versus a comparable population without OLT. The development of nonalcoholic fatty liver disease (NAFLD) after liver transplantation for non-NAFLD cirrhosis is also being increasingly recognized. A number of predictors have been identified as potential risk factors related to these complications. The pretransplant risk factors include immunosuppression, a higher age at transplant, male gender, a history of smoking, the pretransplant body mass index, pre-OLT diabetes, the etiology of the underlying liver disease that resulted in OLT (hepatitis C, cryptogenic cirrhosis, or alcohol), an increased donor body mass index, and marital status. Although there is an increased risk of cardiovascular events, rejection, and infection among patients with PTMS, the overall impact on long-term survival and mortality remains inconclusive. Strategies to reduce the development of metabolic syndrome after transplantation should include lifestyle modifications involving alterations in diet and increased physical activity. Additional measures that may be potentially beneficial include the use of lipid-lowering agents, the optimal control of blood glucose, and the use of tacrolimus instead of cyclosporine.

Long-term medical comorbidities and their management: hypertension/cardiovascular disease

1. There is a high prevalence of cardiovascular risk factors in liver transplant recipients. 2. There is a high incidence of premature onset of cardiovascular disease. 3. The choice of calcineurin inhibitor shows no long-term impact. 4. Established cardiovascular risk scores may determine an individual's risk for cardiovascular events. 5. Posttransplant arterial hypertension is a major burden. 6. Strict surveillance guidelines are needed. 7. Threshold levels for arterial blood pressure according to recommendations for high-risk individuals should be applied. 8. Therapeutic lifestyle changes should be encouraged. 9. Escalating pharmacological treatment with respect to renal function is recommended. 10. Alterations of immunosuppression should be considered.

Renal function and cardiovascular risk profile after conversion from ciclosporin to tacrolimus: prospective study in 80 liver transplant recipients

BACKGROUND

Increased risk of cardiovascular and cerebrovascular disease in liver transplant recipients results in particular from the side effects of calcineurin inhibitor-based immunosuppressive therapy. Several studies have demonstrated a more favourable outcome for patients receiving tacrolimus (TAC) as compared with ciclosporin (CS).

AIM

To investigate the effects of conversion from CS to TAC on cardiovascular risk factors and renal function in liver transplant recipients.

METHODS

In a prospective study, all except two patients had chronic kidney disease stages 2-4 (n = 80), according to estimated glomerular filtration rate using the abbreviated Modification of Diet in Renal Disease equation.

RESULTS

Conversion was accompanied with a mean decrease of total cholesterol from 194.6 +/- 54.0 mg/dL to 175.8 +/- 44.2 mg/dL (P < 0.001), low density lipoprotein cholesterol from 106.7 +/- 39.2 mg/dL to 90.9 +/- 28.6 mg/dL (P < 0.001) and mean arterial blood pressure values from 102.2 +/- 13.2 mm Hg to 95.9 +/- 11.7 mm Hg (P < 0.001). Renal function remained stable. No cases of de novo diabetes mellitus were identified. The Framingham risk score was significantly reduced from 5.2 +/- 4.4 at baseline to 4.4 +/- 5.3 after 12 months (P = 0.006).

CONCLUSIONS

Conversion from CS to TAC has been shown to improve the cardiovascular risk profile and may retard further decline of renal function after liver transplantation.

Trends in 10-year predicted risk of cardiovascular disease in the United States, 1976 to 2004

BACKGROUND

There have been significant bidirectional changes in the prevalence of cardiovascular (CV) risk factors over time in the United States, making the net trend in risk for incident CV disease unknown. We assessed these trends by applying the Framingham Heart Study prediction model to national data.

METHODS AND RESULTS

The National Health and Nutrition Examination Survey (NHANES) II (1976-1980), NHANES III (1988-1994), and NHANES 1999-2004 are cross-sectional representative samples of the noninstitutionalized population of the United States. We excluded people with a history of CV disease, pregnant women, participants with missing CV risk factors data, and individuals outside the Framingham age range of 30 to 74 years. The Framingham risk function was used to estimate the 10-year risk for incident symptomatic CV disease. We calculated the slope of change or rate of change per year between NHANES II and III, and between NHANES III and 1999-2004. The difference between slopes was calculated and compared to zero. The average age-adjusted 10-year CV risk between NHANES II and III decreased from 10.0% to 7.9% between NHANES II and III, with a statistically significant slope (P<0.001). However, the average age-adjusted CV risk decreased at a lesser magnitude between NHANES III and NHANES 1999-2004 from 7.9% to 7.4% (P<0.001). These slopes were significantly different (P<0.0001). In women and middle-aged participants, CV risk did not change between NHANES III and NHANES 1999-2004 (P=0.40).

CONCLUSIONS

The estimated net risk for CV disease in the US population decreased from 1976-1980 to 1988-1994 but has changed minimally from 1988-1994 to 1999-2004, particularly in women and middle-aged people.

Outcome after liver transplantation for NASH cirrhosis

Nonalcoholic steatohepatitis (NASH) associated cirrhosis is an increasing indication for liver transplant (LT). The aim of this study was to determine outcome and poor predictive factors after LT for NASH cirrhosis. We analyzed patients undergoing LT from 1997 to 2008 at a single center. NASH was diagnosed on histopathology. LT recipients with hepatitis C, alcoholic or cholestatic liver disease and cryptogenic cirrhosis acted as matched controls. Ninety-eight LT recipients were identified with NASH cirrhosis. Compared to controls, NASH patients had a higher BMI (mean 32.3 kg/m2), and were more likely to be diabetic and hypertensive. Mortality after transplant was similar between NASH patients and controls but there was a tendency for higher earlier mortality in NASH patients (30-day mortality 6.1%, 1-year mortality 21.4%). Sepsis accounted for half of all deaths in NASH patients, significantly higher than controls. NASH patients > or =60 years, BMI > or =30 kg/m2 with diabetes and hypertension (HTN) had a 50% 1-year mortality. In conclusion, patients undergoing LT for NASH cirrhosis have a similar outcome to patients undergoing LT for other indications. The combination of older age, higher BMI, diabetes and HTN are associated with poor outcome after LT. Careful consideration is warranted before offering LT to these high-risk patients.

Cardiovascular risk after bariatric surgery for obesity

Obese patients have an increased prevalence of cardiovascular (CV) risk factors, which improve with bariatric surgery, but whether bariatric surgery reduces long-term CV events remains ill defined. A systematic review of published research was conducted, and CV risk models were applied in a validation cohort previously published. A standardized MEDLINE search using terms associated with obesity, bariatric surgery, and CV risk factors identified 6 test studies. The validation cohort consisted of a population-based, historical cohort of 197 patients who underwent Roux-en-Y gastric bypass and 163 control patients, identified through the Rochester Epidemiology Project. Framingham and Prospective Cardiovascular Munster Heart Study (PROCAM) risk scores were applied to calculate 10-year CV risk. In the validation cohort, absolute 10-year Framingham risk score for CV events was lower at follow-up in the bariatric surgery group (7.0% to 3.5%, p <0.001) compared with controls (7.1% to 6.5%, p = 0.13), with an intergroup absolute difference in risk reduction of 3% (p <0.001). PROCAM risk in the bariatric surgery group decreased from 4.1% to 2.0% (p <0.001), whereas the control group exhibited only a modest decrease (4.4% to 3.8%, p = 0.08). Using mean data from the validation study, the trend and directionality in risk was similar in the Roux-en-Y group. The test studies confirmed the directionality of CV risk, with estimated relative risk reductions for bariatric surgery patients ranging from 18% to 79% using the Framingham risk score compared with 8% to 62% using the PROCAM risk score. In conclusion, bariatric surgery predicts long-term decreases in CV risk in obese patients.

Preoperative dobutamine stress echocardiographic findings and subsequent short-term adverse cardiac events after orthotopic liver transplantation

Cardiovascular (CV) complications are the leading cause of non-graft-related death in orthotopic liver transplant (OLT) patients. Pretransplant cardiac evaluation using dobutamine stress echocardiography (DSE) is commonly utilized for risk stratification of OLT candidates. To determine if clinical and echocardiographic variables identify patients with increased CV risk, we performed a retrospective chart review of all 284 patients that underwent OLT at our institution between June 1999 and August 2005. Of these patients, 157 had a DSE prior to their OLT. Serious adverse CV events occurring during surgery and up to 4 months post-transplantation were defined as cardiac-related death, myocardial infarction (MI), new heart failure, or asystole or unstable ventricular arrhythmia requiring acute treatment. Sixteen of 157 patients (10%) had an adverse CV event with 2 deaths. These included ventricular tachycardia (n = 8), asystole (n = 2), MI (n = 5), and new heart failure (n = 1). Nine of the 16 CV events occurred at the time of surgery (including both deaths), 5 occurred postoperatively, and 3 occurred after hospital discharge. Variables that correlated with increased CV events were inability during DSE to achieve >82% of the maximum predicted heart rate (22% versus 6%, P = 0.01), a peak rate pressure product during DSE of <16,333 (17% versus 5%, P = 0.02), and a Model for End-Stage Liver Disease (MELD) score of >24 at the time of OLT. A multivariate model calculated from the DSE maximum achieved heart rate (MAHR) and MELD score (result = 3.78 + 0.07 MELD - 0.05 MAHR) identified a 47% risk for a value > 0 versus a 6% risk for a value < 0 (P < 0.001). In conclusion, the maximum heart rate achieved during DSE together with the MELD score may be a predictor of adverse CV events up to 4 months post-OLT. A large prospective study is needed to more decisively support this conclusion.

Hemodynamic evaluation before liver transplantation: insights into the portal hypertensive syndrome

The cardiac hemodynamics of patients awaiting liver transplantation is complex. Coronary atherosclerosis, a hyperdynamic circulatory state and cirrhotic cardiomyopathy are present to a variable degree in this population. In this contribution to the Symposium on Portal Hypertension, we expand on our published experience with coronary angiography and cardiac hemodynamics at the time of evaluation of candidacy for liver transplantation in a cohort of 161 patients. Although we confirmed the relation of systemic hemodynamics with the degree of liver failure, we noted a higher prevalence of high output heart failure, defined as an increased left ventricular end-diastolic pressure in the setting of an elevated cardiac output, most notably in patients classified as Child C. Most patients with high pulmonary artery pressure also exhibited evidence of elevated left ventricle filling pressures. A low systemic vascular resistance, a marker of arterial vasodilatation, was similar in the presence of atherosclerosis, a condition where impaired vasorelaxation occurs as a result of endothelial dysfunction. The high prevalence of coronary artery disease in this series supports the observations that atherosclerosis is a major issue in the current population with cirrhosis awaiting liver transplantation. A lower sensitivity of noninvasive screening tools for the detection of coronary atherosclerosis is likely the result of the interaction of the hyperdynamic circulation with the performance of these tests.

Vascular events after liver transplantation: a long-term follow-up study

Long-term follow-up studies on the impact of vascular events (VE) and risk factors of liver transplant recipients are scarce. In this study, 311 recipients of a first isolated liver transplant who survived at least 1 year were followed up from 1979 to 2002. The median follow-up duration was 6.2 (range1-22.7) years. Overall median survival was 18.7 [95% confidence interval (CI): 15.5-20.1] years and this was significantly lower compared with age- and sex-matched controls. Eleven (21%) of the patients had a vascular cause of death and VE were the third cause of death. VE occurred later compared with other causes of death (mean 10.3 years vs. 4.5 years, P < 0.0001, 95% CI: 2.7-8.9). Systolic hypertension, systolic blood pressure, smoking, renal failure, age, hypertriglyceridemia, serum total cholesterol levels and hypercholesterolemia at the 1-year follow-up visit were associated with the occurrence of VE, but renal failure and age at 1 year after transplantation were the only independent risk factors for vascular death (hazard ratio 0.06, 95% CI: 0.01-0.41 and hazard ratio 1.17, 95% CI: 1.02-1.34, respectively). Finally, it was shown that the adequate treatment of hypertension was associated with a significant reduced risk of vascular death. Therefore, vascular risk factors should be treated aggressively to prevent VE in the long term.

Tacrolimus monotherapy without steroids after liver transplantation--a prospective randomized double-blinded placebo-controlled trial

Early steroid withdrawal after liver transplantation (LT) is desirable in order to reduce steroid side effects. Between February 2000 and August 2004, 110 patients after LT were included in this prospective, randomized, double-blind, placebo-controlled trial. Randomization was performed before LT. In all patients, tacrolimus was used without induction therapy. All patients received methylprednisolon for 14 days, thereafter a double-blinded medication containing either placebo (n = 56) or methylprednisolon (n = 54) for 6 months, which was completely stopped thereafter. End points were patient and graft survival, acute and chronic rejection, and incidence of steroid side effects during the first year after LT. One-year patient survival was 85.7% (placebo) and 88.8% (steroid) (p = 0.572). Twenty-seven (48.2%) and 19 (35.2%) patients experienced acute rejection (placebo versus steroid, respectively; p = 0.116). Two patients in the placebo group but none in the steroid group experienced chronic rejection (p = 0.257). The rates of side effects were (placebo versus steroid, respectively): CMV infection 25% versus 33% (p = 0.336), post-transplant diabetes 30% versus 53% (p = 0.024), hypertension 39% versus 52% (p = 0.248), hypercholesterolemia 10% versus 41% (p = 0.002) and hypertriglyceridemia 32% versus 54% (p = 0.046). In conclusion, early steroid withdrawal after LT is feasible under tacrolimus monotherapy without increased rejection rates and with a lower rate of side effects.

Review article: medical management of the liver transplant recipient - a primer for non-transplant doctors

BACKGROUND

Survival 10 years after orthotopic liver transplantation now approaches 65%. Consequently, community doctors must manage the metabolic and neoplastic complications of orthotopic liver transplantation in an ageing population.

AIMS

To review common sources of morbidity and mortality in long-term orthotopic liver transplantation recipients, and to make evidence-based recommendations regarding their management.

METHODS

Pertinent studies and reviews were identified by literature search through PubMed. Where evidence-based recommendations could not be gleaned from the literature, expert opinion was obtained from syllabi of national meetings.

RESULTS

The two most common causes of morbidity and mortality in orthotopic liver transplantation recipients are atherosclerotic vascular disease and de novo malignancy. The pathogenesis of many complications begins before orthotopic liver transplantation, and many are potentially modifiable. Most complications, however, can be directly ascribed to immunosuppressive agents. Despite improvements in our understanding of the pathogenesis and epidemiology of the metabolic and neoplastic complications of orthotopic liver transplantation, remarkably few randomized-controlled studies exist to define their optimal management.

CONCLUSIONS

Orthotopic liver transplantation recipients experience and succumb to the same afflictions of old age as non-transplant patients, but with greater frequency and at an earlier age. Most recommendations regarding surveillance for, and treatment of, medical complications of orthotopic liver transplantation remain based upon expert opinion rather than evidence-based medicine.