Effectively Screening for Coronary Artery Disease in Patients Undergoing Orthotopic Liver Transplant Evaluation

Cardiac evaluation of the liver transplant candidate

PURPOSE OF REVIEW

This review aims to summarize recent changes in the cardiac evaluation of adult liver transplant candidates. Over the last several years, there have been significant advances in the use of coronary computed tomography angiography (CCTA) with and without fractional flow reserve (FFR) and increasingly widespread availability of coronary calcium scoring for risk stratification for obstructive coronary artery disease. This has led to novel strategies for risk stratification in cirrhotic patients being considered for liver transplant and an updated American Heart Association (AHA) position paper on the evaluation of liver and kidney transplant candidates. The diagnosis of cirrhotic cardiomyopathy has been refined. These new diagnostic criteria require that specific echocardiographic parameters are evaluated in all patients. The definition of pulmonary hypertension on echocardiography has been altered and no longer utilizes right atrium (RA) pressure estimates based on inferior vena cava (IVC) size and collapse. This provides more volume neutral estimates of pulmonary pressure.

RECENT FINDINGS

Although CCTA has outstanding negative predictive value, false positive results are not uncommon and often lead to further testing. Revised diagnostic criteria for cirrhotic cardiomyopathy improve risk stratification for peri-operative volume overload and outcomes. Refined pulmonary hypertension criteria provide improved guidance for right heart catheterization (RHC) and referral to subspecialists. There are emerging data regarding the safety and efficacy of TAVR for severe aortic stenosis in cirrhotic patients.

SUMMARY

Increased utilization of noninvasive testing, including CCTA and/or coronary calcium scoring, can improve the negative predictive value of testing for obstructive coronary artery disease and potentially reduce reliance on coronary angiography. Application of the 2020 criteria for cirrhotic cardiomyopathy will improve systolic and diastolic function assessment and subsequent perioperative risk stratification. The use of global strain scores is emphasized, as it provides important information beyond ejection fraction and diastolic parameters. A standardized one-parameter echo cut-off for elevated pulmonary pressures simplifies both evaluation and follow-up. Innovative transcutaneous techniques for valvular stenosis and regurgitation offer new options for patients at prohibitive surgical risk.

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.

Coronary artery bypass graft combined with liver transplantation in patients with advanced alcoholic liver cirrhosis: A case report

Performing cardiothoracic surgery on patients with advanced liver failure and liver cirrhosis is high-risk for patients. Coronary artery bypass grafting is the most effective treatment for patients with liver failure that is complicated with severe coronary heart disease, and who cannot be treated using coronary stent intervention. In the current study, one case of coronary artery bypass grafting combined with liver transplantation was assessed, with the patient exhibiting advanced alcoholic liver cirrhosis. A coronary artery bypass graft was performed to relieve angina pectoris. Following surgery, wound exudation, secondary infection, liver failure, pleuroperitoneal fluid leakage, hypoproteinemia and other adverse treatment results occurred, and the chest wound did not heal. Allograft liver transplantation was subsequently performed and, following surgery, the chest wound healed gradually after debridement, and the patient recovered.

The Pre-Transplant Profile of Cardiovascular Risk Factors and Its Impact on Long-Term Mortality After Liver Transplantation

BACKGROUND Cardiovascular disease (CVD) is an important aggravating factor for orthotopic liver transplantation (OLT) outcomes. CVD still seems to be one of the most common cause of death in the long-term post-transplant period. Nevertheless, there are some limited data regarding the optimal strategy of risk assessment during OLT candidate evaluation. MATERIAL AND METHODS Routine pre-transplant cardiac workup in 360 patients with end stage liver disease (ESLD) included electrocardiogram, echocardiography, and exercise stress testing. The aim of this retrospective study was an analysis of the impact of cardiovascular risk profile on overall mortality in the 2-year follow-up of 160 patients who underwent liver transplantation. RESULTS Cardiovascular risk factors or a history of CVD were found in 23.1% of patients who received transplants. The cardiovascular risk factors most common in our group of transplant recipients with ESLD were: diabetes (26.3%), hypertension (25.6%), and hepatopulmonary syndrome (23.1%). Only 3.8% of patients had a positive exercise test. Coronary angiography revealed at least 50% stenosis in some epicardial arteries in 1.9% of patients. The risk of death in long-term follow-up of liver transplant recipients was most strongly associated with 3 cardiac variables: history of coronary artery disease (CAD), angiographically confirmed coronary stenosis, and reduced ejection fraction (EF). CONCLUSIONS Our study identified pre-transplant CAD with its consequences as a factor associated with increased risk of negative post-transplant outcomes.

Cardiac diseases among liver transplant candidates

Improvements in early survival after liver transplant (LT) have allowed for the selection of LT candidates with multiple comorbidities. Cardiovascular disease is a major contributor to post-LT complications. We performed a literature search to identify the causes of cardiac disease in the LT population and to describe techniques for diagnosis and perioperative management. As no definite guidelines for preoperative assessment (except for pulmonary heart disease) are currently available, we recommend an algorithm for preoperative cardiac work-up.

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.