The predictors of post-transplant coronary events among liver transplant recipients. Hepatol Int. 2016;10:974-982. [PMID: 27311889 DOI: 10.1007/s12072-016-9742-5]

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.

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.

Diagnostic accuracy of cardiac testing for coronary artery disease in potential liver transplant recipients: A systematic review and meta-analysis

Background

The incidence of coronary artery disease (CAD) in Liver transplant (LT) patients is much higher than prior estimates and the morbidity and mortality are significant in this group of patients. Coronary angiography is the gold standard for detection of CAD, a non-invasive test that allows appropriate risk stratification would be preferred. In this systematic review and meta-analysis, we sought to assess the pooled diagnostic accuracy of various noninvasive cardiac imaging tests in detecting CAD in patients listed for LT.

Methods

We performed a systematic review and meta-analysis of studies comparing sensitivity and specificity of non-invasive tests to that of coronary angiography in diagnosing coronary artery disease in patients undergoing liver transplantation.

Results

Five studies (616 participants) evaluated myocardial perfusion imaging (MPI); five studies (1243 participants) dobutamine stress echocardiography (DSE); and three (87 participants), other tests. MPI had a pooled sensitivity of 0.62 (95% CI 0.37, 0.83), specificity of 0.60 (95% CI 0.39, 0.79), diagnostic odds ratio (DOR) of 2.5 (95% CI 1.7, 5.64) and Area under the curve (AUC) 0.649. DSE had a pooled sensitivity of 0.25 (95%CI 0.09, 0.51), specificity of 0.68 (95% CI 0.44, 0.84) and DOR of 0.7 (95% CI 0.12, 3.84).

Conclusions

Our results show that both MPI and DSE are not effective screening tools for detecting CAD in patients with end-stage liver disease (ESLD). Future studies are needed to evaluate the role of real-time myocardial contrast echocardiography (RTMCE) and coronary artery calcium score (CAC) with coronary CT angiography in patients with ESLD.

Pretransplant coronary artery disease is a predictor for myocardial infarction and cardiac death after liver transplantation

BACKGROUND

Cardiovascular disease is a serious problem of liver transplant (LT) recipients because of increased cardiovascular risk due to immunosuppressive therapy, higher age, intraoperative risk and comorbidities (such as diabetes and nicotine abuse). Reported frequency of cardiovascular events after LT shows a high variability between different LT cohorts. Our aim was to analyze a cohort of LT recipients from a single center in Germany to evaluate frequency of the cardiovascular endpoints (CVE) myocardial infarction and/or cardiac death after LT and to investigate correlations of CVE post LT with pretransplant patient characteristics.

PATIENTS

In total, data from 352 LT patients were analyzed. Patients were identified from an administrative transplant database, and all data were retrieved from patients' charts and reports.

RESULTS

During the median follow-up of 4.0 (0-13) years, 10 cases of CVE were documented (six myocardial infarctions and four coronary deaths). The frequency of CVE did not differ according to classic cardiovascular risk factors such as body mass index (p=0.071), total cholesterol (p=0.533), hypertension (p=0.747), smoking (p=1.000) and pretransplant diabetes mellitus (p=0.146). In patients with pretransplant coronary heart disease (n=24; 6.8%) CVE were found more frequently (p=0.024).

CONCLUSION

In summary, we found a rate of 2.8% CVE after LT in a German transplant cohort. Pretransplant CHD was the only risk factor for CVE, but showed no significant impact on overall survival.

Potentially inappropriate liver transplantation in the era of the "sickest first" policy - A search for the upper limits

Liver transplantation has emerged as a highly efficient treatment for a variety of acute and chronic liver diseases. However, organ shortage is becoming an increasing problem globally, limiting the applicability of liver transplantation. In addition, potential recipients are becoming sicker, thereby increasing the risk of losing the graft during transplantation or in the initial postoperative period after liver transplantation (three months). This trend is challenging the model for end-stage liver disease allocation system, where the sickest candidates are prioritised and no delisting criteria are given. The weighting of the deontological demand for "equity", trying to save every patient, regardless of the overall utility; and "efficiency", rooted in utilitarianism, trying to save as many patients as possible and increase the overall quality of life of patients facing the same problem, has to be reconsidered. In this article we are aiming to overcome the widespread concept of futility in liver transplantation, providing a definition of potentially inappropriate liver transplantation and giving guidance on situations where it is best not to proceed with liver transplantation, to decrease the mortality rate in the first three months after transplantation. We propose "absolute" and "relative" conditions, where early post-transplant mortality is highly probable, which are not usually captured in risk scores predicting post-transplant survival. Withholding liver transplantation for listed patients in cases where liver transplant is not deemed clearly futile, but is potentially inappropriate, is a far-reaching decision. Until now, this decision had to be discussed extensively on an individual basis, applying explicit communication and conflict resolution processes, since the model for end-stage liver disease score and most international allocation systems do not include explicit delisting criteria to support a fair delisting process. More work is needed to better identify cases where transplantation is potentially inappropriate and to integrate and discuss these delisting criteria in allocation systems, following a societal debate on what we owe to all liver transplant candidates.

Addictive behaviors in liver transplant recipients: The real problem?

Liver transplantation (LT) is the gold standard treatment for end-stage liver disease. Whatever the primary indication of LT, substance abuse after surgery may decrease survival rates and quality of life. Prevalence of severe alcohol relapse is between 11 and 26%, and reduces life expectancy regardless of the primary indication of LT. Many patients on waiting lists for LT are smokers and this is a major risk factor for both malignant tumors and cardiovascular events post-surgery. The aim of this review is to describe psychoactive substance consumption after LT, and to assess the impact on liver transplant recipients. This review describes data about alcohol and illicit drug use by transplant recipients and suggests guidelines for behavior management after surgery. The presence of an addiction specialist in a LT team seems to be very important.

Outcome of Liver Transplant Recipients With Revascularized Coronary Artery Disease: A Comparative Analysis With and Without Cardiovascular Risk Factors

BACKGROUND

Coronary artery disease (CAD) is a significant problem during evaluation for liver transplantation (LT). We aim to assess survival in LT recipients based on presence, severity, extent of CAD, and cardiac events within 90 days of LT.

METHODS

Eighty-seven LT recipients with history of pre-LT angiogram (December 2005 to December 2012) were compared with 2 control groups without prior angiogram, 72 LT recipients matched for cardiovascular risk factors (control group I), and 119 consecutive LT recipients without any CV risk factors (control group II). CAD was assessed by (1) vessel score (≥50% reduction in luminal diameter), and (2) Extent score (Reardon scoring system).

RESULTS

Of the 87 LT recipients (study group), 58 (66.7%) had none or less than 50% stenosis, 29 (33.3%) had obstructive CAD (≥50% stenosis), 7 (8%) with single-vessel disease, and 22 (25.3%) with multivessel disease. In the study group, irrespective of prerevascularization severity of CAD (P = 0.357), number of segments involved (0, 1-2, > 2 segments, P = 0.304) and extent of CAD based on Reardon score (0, 1-9, >10, P = 0.224), comparable posttransplant survival was noted. Overall, patient survival in the revascularized CAD group was comparable to angiogram group without obstructive CAD, and both control group I and control group II (P = 0.184, Log Rank). Postoperative cardiac events within 90 days of LT predicted poor survival in study group as well as control groups.

CONCLUSIONS

Severity or extent of CAD does not impact post-LT survival, if appropriately revascularized. Early postoperative cardiac events are associated with inferior survival in LT recipients, irrespective of underlying CAD.