Accuracy of stress myocardial perfusion imaging to diagnose coronary artery disease in end stage liver disease patients

Perioperative Cardiovascular Risk Assessment and Management in Liver Transplant Recipients: A Review of the Literature Merging Guidelines and Interventions

Liver transplantation (LT) is the second most performed solid organ transplant. Coronary artery disease (CAD) is a critical consideration for LT candidacy, particularly in patients with known CAD or risk factors, including metabolic dysfunction associated with steatotic liver disease. The presence of severe CAD may exclude patients from LT; therefore, precise preoperative evaluation and interventions are necessary to achieve transplant candidacy. Cardiovascular complications represent the earliest nongraft-related cause of death post-transplantation. Timely intervention to reduce cardiovascular events depends on adequate CAD screening. Coronary disease screening in end-stage liver disease is challenging because standard noninvasive CAD screening tests have low sensitivity due to hyperdynamic state and vasodilatation. As a result, there is overuse of invasive coronary angiography to exclude severe CAD. Coronary artery calcium scoring using a computed tomography scan is a tool for the prediction of cardiovascular events, and can be used to achieve risk stratification in LT candidates. Recent literature shows that qualitative assessment on both noncontrast- and contrast-enhanced chest computed tomography can be used instead of calcium score to assess the presence of coronary calcium. With increasing prevalence, protocols to address CAD in LT candidates must be reconsidered. Percutaneous coronary intervention could allow a shorter duration of dual-antiplatelet therapy in simple lesions, with safer perioperative outcomes. Hybrid coronary revascularization is an option for high-risk LT candidates with multivessel disease nonamenable to percutaneous coronary intervention. The objective of this review is to evaluate existing methods for preoperative cardiovascular risk stratification, and to describe interventions before surgery to optimize patient outcomes and reduce cardiovascular event risk.

Optimizing cardiac status in the preliver transplant candidate

PURPOSE OF REVIEW

Liver transplant is a widely accepted therapy for end-stage liver disease. With advances in our understanding of transplant, candidates are increasingly older with more cardiac comorbidities. Cardiovascular disease also represents a leading cause of morbidity and mortality posttransplant.

RECENT FINDINGS

Preoperative cardiac risk stratification and treatment may improve short-term and long-term outcomes after liver transplant. Importantly, the appropriate frequency of surveillance has not been defined. Optimal timing of cardiac intervention in end-stage liver disease is likewise uncertain.

SUMMARY

The approach to risk stratification of cardiovascular disease in end-stage liver disease is outlined, incorporating the AHA/ACC scientific statement on evaluation of cardiac disease in transplant candidates and more recent expert consensus documents. Further study is needed to clarify the ideal timing and approach for cardiovascular interventions.

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.

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.

Diagnostic accuracy of myocardial perfusion imaging in patients evaluated for kidney transplantation: A systematic review and meta-analysis

BACKGROUND

Cardiovascular disease is the most common cause of death after kidney transplantation. Coronary artery disease (CAD) assessment is therefore mandatory in patients evaluated for transplantation. We aimed to assess the diagnostic accuracy for CAD of single-photon emission computed tomography (SPECT) compared to the standards invasive coronary angiography (ICA) and coronary computed tomography angiography (CCTA) in patients evaluated for kidney transplantation.

METHODS

We performed a systematic literature search in PubMed, EMBASE, Web of Science, OvidSP (Medline), The Cochrane Library and Google Scholar. Studies investigating the diagnostic accuracy of myocardial perfusion imaging (MPI) SPECT in patients evaluated for kidney transplantation were retrieved. After a risk of bias assessment using QUADAS-2, a meta-analysis was conducted.

RESULTS

Out of 1459 records, 13 MPI SPECT studies were included in the meta-analysis with a total of 1245 MPI SPECT scans. There were no studies available with CCTA as reference. Pooled sensitivity of MPI SPECT for CAD was 0.66 (95% CI 0.53 to 0.77), pooled specificity was 0.75 (95% CI 0.63 to 0.84) and the area under the curve (AUC) was 0.76. Positive likelihood ratio was 2.50 (95% CI 1.78 to 3.51) and negative likelihood ratio was 0.41 (95% CI 0.28 to 0.61). Pooled positive predictive value was 64.9% and pooled negative predictive value was 74.1%. Significant heterogeneity existed across the included studies.

CONCLUSIONS

MPI SPECT had a moderate diagnostic accuracy in patients evaluated for kidney transplantation, with a high rate of false-negative findings. The use of an anatomical gold standard against a functional imaging test in the included studies is however suboptimal.

Emerging Evidence on Coronary Heart Disease Screening in Kidney and Liver Transplantation Candidates: A Scientific Statement From the American Heart Association: Endorsed by the American Society of Transplantation

Coronary heart disease is an important source of mortality and morbidity among kidney transplantation and liver transplantation candidates and recipients and is driven by traditional and nontraditional risk factors related to end-stage organ disease. In this scientific statement, we review evidence from the past decade related to coronary heart disease screening and management for kidney and liver transplantation candidates. Coronary heart disease screening in asymptomatic kidney and liver transplantation candidates has not been demonstrated to improve outcomes but is common in practice. Risk stratification algorithms based on the presence or absence of clinical risk factors and physical performance have been proposed, but a high proportion of candidates still meet criteria for screening tests. We suggest new approaches to pretransplantation evaluation grounded on the presence or absence of known coronary heart disease and cardiac symptoms and emphasize multidisciplinary engagement, including involvement of a dedicated cardiologist. Noninvasive functional screening methods such as stress echocardiography and myocardial perfusion scintigraphy have limited accuracy, and newer noninvasive modalities, especially cardiac computed tomography-based tests, are promising alternatives. Emerging evidence such as results of the 2020 International Study of Comparative Health Effectiveness With Medical and Invasive Approaches-Chronic Kidney Disease trial emphasizes the vital importance of guideline-directed medical therapy in managing diagnosed coronary heart disease and further questions the value of revascularization among asymptomatic kidney transplantation candidates. Optimizing strategies to disseminate and implement best practices for medical management in the broader end-stage organ disease population should be prioritized to improve cardiovascular outcomes in these populations.

Evaluation of liver transplant candidates with non-alcoholic steatohepatitis

Non-alcoholic steatohepatitis (NASH) is anticipated to become the leading indication for liver transplantation (LT) in the United States in the near future. LT is indicated in patients with NASH-related cirrhosis who have medically refractory hepatic decompensation, synthetic dysfunction, and hepatocellular carcinoma (HCC) meeting certain criteria. The objective of LT evaluation is to determine which patient will derive the most benefit from LT with the least risk, thus maximizing the societal benefits of a limited resource. LT evaluation is a multidisciplinary undertaking involving several specialists, assessment tools, and diagnostic testing. Although the steps involved in LT evaluation are relatively similar across different liver diseases, patients with NASH-related cirrhosis have unique demographic and clinical features that affect transplant outcomes and influence their LT evaluation. LT candidates with NASH should be assessed for metabolic syndrome and obesity, malnutrition and sarcopenia, frailty, and cardiovascular disease. Interventions that treat cardiometabolic co-morbidities and improve patients' nutrition and functionality should be considered in order to improve patient outcomes in the waitlist and after LT.

Cardiac risk stratification of the liver transplant candidate: A comprehensive review

Cardiovascular diseases (CVD) form a principal consideration in patients with end-stage liver disease (ESLD) undergoing evaluation for liver transplant (LT) with prognostic implications in the peri- and post-transplant periods. As the predominant etiology of ESLD continues to evolve, addressing CVD in these patients has become increasingly relevant. Likewise, as the number of LTs increase by the year, the proportion of older adults on the waiting list with competing comorbidities increase, and the demographics of LT candidates evolve with parallel increases in their CVD risk profiles. The primary goal of cardiac risk assessment is to preemptively reduce the risk of cardiovascular morbidity and mortality that may arise from hemodynamic stress in the peri- and post-transplant periods. The complex hemodynamics shared by ESLD patients in the pre-transplant period with adverse cardiovascular events occurring in only some of these recipients continue to challenge currently available guidelines and their uniform applicability. This review focusses on cardiac assessment of LT candidates in a stepwise manner with special emphasis on preoperative patient optimization. We hope that this will reinforce the importance of cardiovascular optimization prior to LT, prevent futile LT in those with advanced CVD beyond the stage of optimization, and thereby use the finite resources prudently.

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.

Diagnostic Yield of Coronary Angiography in Asymptomatic Orthotopic Liver Transplantation Candidates

BACKGROUND

The ideal cardiac risk stratification strategy for orthotopic liver transplantation (OLT) is unknown. Our institution performed coronary angiography for asymptomatic OLT candidates at high risk for CAD: ≥65 years of age, diabetic and ≥55 years of age or diagnosed ≥5 years, abnormal stress test, or at the discretion of the OLT committee.

METHODS

The analysis included 301 consecutive, asymptomatic OLT candidates who underwent coronary angiography. The primary outcome was the prevalence of obstructive CAD.

RESULTS

At 2-year follow-up, OLT was performed in 44.9%, and 42.2% died. The prevalence of obstructive CAD, involvement of the proximal or mid LAD, and 3-vessel CAD were 10.3%, 6.6%, and 0.7%, respectively. Percutaneous and surgical revascularization were performed in 7.0% and 1.3%, respectively. Stress test was performed in 54.8%. The sensitivity and specificity of stress testing were 0% and 87.1%, respectively. The negative and positive predictive values of stress testing were 91.4% and 0%, respectively. Chest computed tomography (CT) was performed in 83.1%. Moderate or severe coronary artery calcification (CAC) was present in 47.8%. The sensitivity and specificity of moderate or severe CAC were 88.9% and 57.3%, respectively. The negative and positive predictive values of moderate or severe CAC were 97.7% and 20.2%, respectively. Multivariate analysis demonstrated that CAC was an independent predictor of obstructive CAD (HR 10.7; 95% CI 3.2-37.9; p < 0.001).

CONCLUSIONS

The prevalence of obstructive CAD in asymptomatic OLT candidates at high risk was uncommon. Alternative diagnostic strategies may be preferred to coronary angiography.

Use of Computed Tomography Coronary Calcium Score for Coronary Artery Disease Risk Stratification During Liver Transplant Evaluation

Background

End-stage liver disease (ESLD) is not considered a risk factor for atherosclerotic cardiovascular disease (ASCVD). However, lifestyle characteristics commonly associated with increased ASCVD risk are highly prevalent in ESLD. Emerging literature shows a high burden of asymptomatic coronary artery disease (CAD) in patients with ESLD and a high ASCVD risk in liver transplantation (LT) recipients. Coronary artery calcium score (CAC) is a noninvasive test providing reliable CAD risk stratification. We implemented an LT evaluation protocol with CAC playing a central role in triaging and determining the need for further CAD assessment. Here, we inform our results from this early experience.

Methods

Patients with ESLD referred for LT evaluation were prospectively studied. We compared accuracy of CAC against that of CAD risk factors/scores, troponin I, dobutamine stress echocardiogram (DSE), and single-photon emission computed tomography (SPECT) to detect coronary stenosis ≥70 (CAD ≥ 70) per left heart catheterization (LHC). Thirty-day post-LT cardiac outcomes were also analyzed.

Results

One hundred twenty-four of 148 (84%) patients underwent CAC, 106 (72%) DSE/SPECT, and 50 (34%) LHC. CAC ≥ 400 was found in 35 (28%), 100 to 399 in 17 (14%), and <100 in 72 (58%). LHC identified CAD ≥ 70% in 8 of 29 (28%), 2 of 9 (22%), and 0 of 4, respectively. Two acute coronary syndromes occurred after LT in a patient with CAC 811 (CAD < 70%), and one with CAC 347 (CAD ≥ 70%). No patients with CAC < 100 presented with acute coronary syndrome after LT. When using CAD ≥ 70% as primary endpoint of LT evaluation, CAC ≥ 346 was the only test showing predictive usefulness (negative predictive value 100%).

Conclusions

CAC is a promising tool to guide CAD risk stratification and need for LHC during LT evaluation. Patients with a CAC < 100 can safely undergo LT without the need for LHC or cardiac stress testing, whereas a CAC < 346 accurately rules out significant CAD stenosis (≥70%) on LHC, outperforming other CAD risk-stratification strategies.

How will NAFLD change the liver transplant landscape in the 2020s?

Liver steatosis is the hepatic manifestation of the metabolic syndrome, and is now the leading cause of chronic liver disease worldwide. The treatment of metabolic cirrhosis with liver failure and/or hepatocellular carcinoma is liver transplantation (LT). During the past decade, metabolic cirrhosis represented an increasing cause for LT, especially in the United States. At listing, patients with metabolic cirrhosis are older, with numerous cardiovascular (CV) and renal comorbidities, and this requires multidisciplinary pre-transplant assessment. After LT, 5-year survival is similar to other indications. The leading causes of death are infectious, cancers and CV. The recurrence of the initial disease is very frequent, and a significant part of the patients progress towards graft cirrhosis. No specific immunosuppressive regimen is recommended, but the toxicity profiles must probably be taken into account. In these patients, the only etiological treatment is that of obesity, in the absence of specific therapy for non-alcoholic steatohepatitis. The place of bariatric surgery has to be defined, probably sleeve gastrectomy, in a stable patient, 6-12 months after LT.

The fundamental role of stress echo in evaluating coronary artery disease in specific patient populations

Stress echocardiography (SE) was initially used for assessing patients with known or suspected coronary heart disease by detecting and evaluating myocardial ischemia and viability. The implementation of SE has gradually been extended to several cardiovascular diseases beyond coronary artery disease, and SE protocols have been modified and adapted for the detection of coronary artery disease (CAD) or other cardiovascular diseases in specific patient populations. This review attempts to summarize current data concerning SE implementation and clinical value in these specific and diverse populations: patients with an intramural course of a coronary artery - known as a myocardial bridge, chronic severe or end-stage hepatic disease, chronic severe or end-stage kidney disease, cardiac allograft vasculopathy, patients scheduled for solid-organ transplantation and other intermediate and high-risk surgery and, finally, patients treated with anticancer drugs or radiotherapy.

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).

Cardiovascular Evaluation of Liver Transplant Patients by Using Coronary Calcium Scoring in ECG-Synchronized Computed Tomographic Scans

Background: The goal of cardiac evaluation of patients awaiting orthotopic liver transplantation (OLT) is to identify the patients at risk for cardiovascular events (CVEs) in the peri- and postoperative periods by opportunistic evaluation of coronary artery calcium (CAC) in non-gated abdominal computed tomographs (CT). Methods: We hypothesized that in patients with OLT, a combination of Lee’s revised cardiac index (RCRI) and CAC scoring would improve diagnostic accuracy and prognostic impact compared to non-invasive cardiac testing. Therefore, we retrospectively evaluated 169 patients and compared prediction of CVEs by both methods. Results: Standard workup identified 22 patients with a high risk for CVEs during the transplant period, leading to coronary interventions. Eighteen patients had a CVE after transplant and a CAC score > 0. The combination of CAC and RCRI ≥ 2 had better negative (NPV) and positive predictive values (PPV) for CVEs (NPV 95.7%, PPV 81.6%) than standard non-invasive stress tests (NPV 92.0%, PPV 54.5%). Conclusion: The cutoff value of CAC > 0 by non-gated CTs combined with RCRI ≥ 2 is highly sensitive for identifying patients at risk for CVEs in the OLT population.

CAD-LT score effectively predicts risk of significant coronary artery disease in liver transplant candidates

BACKGROUND & AIMS

Patients with cirrhosis and significant coronary artery disease (CAD) are at risk of peri-liver transplantation (LT) cardiac events. The coronary artery disease in liver transplantation (CAD-LT) score and algorithm aim to predict the risk of significant CAD in LT candidates and guide pre-LT cardiac evaluation.

METHODS

Patients who underwent pre-LT evaluation at Indiana University (2010-2019) were studied retrospectively. Stress echocardiography (SE) and cardiac catheterization (CATH) reports were reviewed. CATH was performed for predefined CAD risk factors, irrespective of normal SE. Significant CAD was defined as CAD requiring percutaneous or surgical intervention. A multivariate regression model was constructed to assess risk factors. Receiver-operating curve analysis was used to compute a point-based risk score and a stratified testing algorithm.

RESULTS

A total of 1,771 pre-LT patients underwent cardiac evaluation, including results from 1,634 SE and 1,266 CATH assessments. Risk-adjusted predictors of significant CAD at CATH were older age (adjusted odds ratio 1.05; 95% CI 1.03-1.08), male sex (1.69; 1.16-2.50), diabetes (1.57; 1.12-2.22), hypertension (1.61; 1.14-2.28), tobacco use (pack years) (1.01; 1.00-1.02), family history of CAD (1.63; 1.16-2.28), and personal history of CAD (6.55; 4.33-9.90). The CAD-LT score stratified significant CAD risk as low (≤2%), intermediate (3% to 9%), and high (≥10%). Among patients who underwent CATH, a risk-based testing algorithm (low: no testing; intermediate: non-invasive testing vs. CATH; high: CATH) would have identified 97% of all significant CAD and potentially avoided unnecessary testing (669 SE [57%] and 561 CATH [44%]).

CONCLUSIONS

The CAD-LT score and algorithm (available at www.cad-lt.com) effectively stratify pre-LT risk for significant CAD. This may guide more targeted testing of candidates with fewer tests and faster time to waitlist.

LAY SUMMARY

The coronary artery disease in liver transplantation (CAD-LT) score and algorithm effectively stratify patients based on their risk of significant coronary artery disease. The CAD-LT algorithm can be used to guide a more targeted cardiac evaluation prior to liver transplantation.

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.

Cardiac evaluation of the kidney or liver transplant candidate

PURPOSE OF REVIEW

As the field of transplant has advanced, cardiac events have become the leading cause of morbidity and mortality after liver and kidney transplantation ahead of graft failure and infection. This trend has been bolstered by the transplantation of older and sicker patients who have a higher burden of cardiovascular risk factors, accentuating the need to determine which patients should undergo more extensive cardiac evaluation prior to transplantation.

RECENT FINDINGS

Computed tomography coronary angiography with or without coronary artery calcium scoring is now preferred over stress imaging in most transplant candidates for assessment of coronary artery disease. Assessment of cardiac structure and function using transthoracic echocardiography with tissue doppler imaging and strain imaging is recommended, particularly in liver transplant candidates who are at high risk of cirrhotic cardiomyopathy, for which new diagnostic criteria were recently published in 2019.

SUMMARY

Cardiac evaluation of liver and kidney transplant candidates requires a global assessment for both short and long-term risk for cardiac events. Imaging of cardiac structure and function using transthoracic echocardiography with tissue doppler imaging and strain imaging is recommended. Risk stratification should consider both the anatomic and functional consequences of coronary artery disease in transplant candidates.

VIDEO ABSTRACT

http://links.lww.com/MOT/A27.

Preoperative Evaluation of Coronary Artery Disease in Liver Transplant Candidates: Many Unanswered Questions in Clinical Practice

Cardiovascular (CV) complications represent the first non-graft-related cause of death and the third overall cause of death among patients undergoing liver transplantation (LT). History of coronary artery disease is related to increased CV mortality following LT. Although it is of paramount importance to stratify CV risk in pre-LT patients, there is no consensus regarding the choice of the optimal non-invasive cardiac imaging test. Algorithms proposed by scientific associations include non-traditional risk factors, which are associated with increased cardiac risk profiles. Thus, an individualized pre-LT evaluation protocol should be followed. As the average age of patients undergoing LT and the number of candidates continue to rise, the “3 W” questions still remain unanswered, Who, Which and When? Who should be screened for coronary artery disease (CAD), which screening modality should be used and when should the asymptomatic waitlisted patients repeat cardiac evaluation? Prospective studies with large sample sizes are warranted to define an algorithm that can provide better risk stratification and more reliable survival prediction.

Quantitative blood flow evaluation of vasodilation-stress compared with dobutamine-stress in patients with end-stage liver disease using 82Rb PET/CT

BACKGROUND

Our aim was to determine if end-stage liver disease (ESLD) is associated with an attenuated response to vasodilator-stress or dobutamine-stress using 82Rb-PET MPI with blood flow quantification.

METHODS AND RESULTS

Pre-liver transplant patients who had a normal dipyridamole-stress (n = 27) or dobutamine-stress (n = 26) 82Rb PET/CT MPI study with no identifiable coronary artery calcium were identified retrospectively and compared to a prospectively identified low-risk of liver disease dipyridamole-stress control group (n = 20). The dipyridamole-stress liver disease group had a lower myocardial flow reserve (MFR) (1.89 ± 0.79) than the control group (2.79 ± 0.96, P < .05). The dobutamine-stress group had a higher MFR than both other groups (3.69 ± 1.49, P < .05). A moderate negative correlation between MELD score and MFR was demonstrated for the dipyridamole-stress liver disease group (r = - 0.473, P < .05). This correlation was not observed for the dobutamine-stress liver disease group (r = - 0.253, P = .21). The liver failure group as a whole (n = 53) had a higher resting myocardial blood flow (0.97 ± 0.33 mL/min/g) than the control group (0.82 ± 0.26, P < .05).

CONCLUSION

Dipyridamole demonstrates an attenuated vasodilatory response in ESLD patients compared to a non-ESLD control group related to higher resting blood flow and comparatively reduced stress blood flow. Dobutamine does not demonstrate this effect implying it may be the preferred pharmacologic MPI stress agent for ESLD patients.

Intraoperative Type I Acute Myocardial Infarction During Liver Transplant Requiring Intra-Aortic Balloon Pump: A Case Report

We describe a complex case of liver transplant in a 70-year-old male patient with no known history of coronary artery disease, normal preoperative left ventricular function, and negative preoperative cardiac workup who developed progressive intra-operative left ventricular myocardial dysfunction secondary to class I acute myocardial infarction, ultimately requiring intraoperative intra-aortic balloon pump insertion to optimize myocardial perfusion. Management of myocardial ischemia was complicated by bleeding in the setting of coagulopathy necessitating correction. Once hemostasis was achieved, the patient immediately underwent coronary angiography and bare metal stent placement in the mid-left anterior descending coronary artery for an acute plaque rupture.

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.

Clinical impact of low-radiation computed tomography coronary angiography diagnosis for coronary artery stenosis: Study Protocol

BACKGROUND

The objective of this study aims to assess the clinic impact of low-radiation computed tomography coronary angiography (LR-CTCA) diagnosis for coronary artery stenosis (CAS).

METHODS

This study will comprehensively search the following electronic databases from inception to the present: PUBMED, EMBASE, Cochrane Library, PsycINFO, Web of Science, Google, Allied and Complementary Medicine Database, Chinese Biomedical Literature Database, VIP database, WANGFANG, and China National Knowledge Infrastructure. All these electronic databases will be searched without language restrictions. All case-controlled studies on assessing the clinical impact of LR-CTCA diagnosis for patients with CAS will be included. Quality Assessment of Diagnostic Accuracy Studies tool will be utilized to evaluate the methodological quality for each qualified studies.

RESULTS

We will assess the clinic impact of LR-CTCA diagnosis for CAS by measuring sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio.

CONCLUSION

The results of this study will summarize the latest evidence of LR-CTCA diagnosis for CAS.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42019139336.

Significance of Coronary Artery Calcium Found on Non-Electrocardiogram-Gated Computed Tomography During Preoperative Evaluation for Liver Transplant

Guidelines to evaluate patients for coronary artery disease (CAD) during preoperative evaluation for orthotopic liver transplantation (OLT) are conflicting. Cardiac catheterization is not without risk in patients with end-stage liver disease. No study to date has looked at the utility of non-electrocardiogram-gated chest computed tomography (CT) in the preliver transplant population. Our hypothesis was that coronary artery calcium scores (CACSs) from chest CT scans ordered during the liver transplant workup can identify patients who would benefit from invasive angiography. Nine hundred and fifty-three patients who underwent coronary angiography as part of their OLT workup were considered. Charts were randomly selected and reviewed for the presence of a chest CT performed before coronary angiography during the OLT workup. Agatston and Weston scores were calculated. CACS results were compared with coronary angiography findings. Nine of 54 patients were found to have obstructive CAD by angiography. Receiver-operating characteristic analysis demonstrated that an Agatston score of 251 and a Weston score of 6 maximized sensitivity and specificity for detection of obstructive coronary disease. An Agatston score <4 or Weston score <2 excluded the presence of obstructive CAD; using these thresholds, 13 patients (24%) or 15 patients (28%), respectively, could have theoretically avoided catheterization without missing significant CAD. In conclusion, our data identify the strength of CACS in ruling out coronary disease in patients being evaluated for OLT. Calcium scoring from non-electrocardiogram-gated CT studies may be integrated into preoperative algorithms to rule out obstructive CAD and help avoid invasive angiography in this high-risk population.

The relationship between coronary artery disease and cardiovascular events early after liver transplantation

BACKGROUND & AIMS

Cardiovascular complications are major contributors to mortality at liver transplantation (LT). However, the impact of coronary artery disease (CAD) on these complications is not well-understood as the literature is limited by non-invasive assessment of CAD, which is suboptimal in patients with cirrhosis. Thus, the current study evaluated cardiovascular events at LT stratified according to the presence and severity of CAD quantified on coronary angiography.

METHODS

All patients who had LT from January 2010 to January 2017 were evaluated (N = 348), but analysis was restricted to patients who had coronary angiography prior to LT (N = 283). Protocol coronary angiography was performed in all patients' ages >50 years, history of CAD, abnormal cardiac stress test or risk factors for CAD. The primary outcome was a cardiovascular composite outcome including myocardial infraction (MI), cardiac arrest, stroke, cardiac death, heart failure or arrhythmia occurring within 4 weeks after LT.

RESULTS

CAD was present in 92(32.5%) patients and 32(11.3%) had obstructive CAD. During the study period, 72(25.4%) patients met the primary cardiovascular outcome, the most common being arrhythmia (N = 59 or 20.8%). Non-ST elevation MI occurred in 11(3.9%) of patients. A total of 10 deaths (3.5%) occurred, of which 6(2.1%) were attributable to cardiac death. There was no evidence of a relationship between the presence and severity of CAD and composite cardiovascular events. In multiple regression modelling, only diabetes [OR 2.62, 95%CI (1.49, 4.64), P < 0.001] was associated with the likelihood of having a cardiovascular event.

CONCLUSION

Cardiovascular disease mortality is the most important contributor of early mortality after LT but is not related to the severity of CAD.

International Liver Transplantation Consensus Statement on End-stage Liver Disease Due to Nonalcoholic Steatohepatitis and Liver Transplantation

Nonalcoholic steatohepatitis (NASH)-related cirrhosis has become one of the most common indications for liver transplantation (LT), particularly in candidates older than 65 years. Typically, NASH candidates have concurrent obesity, metabolic, and cardiovascular risks, which directly impact patient evaluation and selection, waitlist morbidity and mortality, and eventually posttransplant outcomes. The purpose of these guidelines is to highlight specific features commonly observed in NASH candidates and strategies to optimize pretransplant evaluation and waitlist survival. More specifically, the working group addressed the following clinically relevant questions providing recommendations based on the Grading of Recommendation, Assessment, Development and Evaluation (GRADE) system supported by rigorous systematic reviews and consensus: (1) Is the outcome after LT similar to that of other etiologies of liver disease? (2) Is the natural history of NASH-related cirrhosis different from other etiologies of end-stage liver disease? (3) How should cardiovascular risk be assessed in the candidate for LT? Should the assessment differ from that done in other etiologies? (4) How should comorbidities (hypertension, diabetes, dyslipidemia, obesity, renal dysfunction, etc.) be treated in the candidate for LT? Should treatment and monitoring of these comorbidities differ from that applied in other etiologies? (5) What are the therapeutic strategies recommended to improve the cardiovascular and nutritional status of a NASH patient in the waiting list for LT? (6) Is there any circumstance where obesity should contraindicate LT? (7) What is the optimal time for bariatric surgery: before, during, or after LT? (8) How relevant is donor steatosis for LT in NASH patients?

Screening of Cardiovascular Disease in Nonalcoholic Fatty Liver Disease: Whom and How?

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide. Patients with NAFLD are at a higher risk of developing cardiovascular disease (CVD). In fact, CVD-related mortality is more common in patients with NAFLD in comparison to liver-related mortality. This association is related to the common metabolic risk factors such as obesity, dyslipidemia, diabetes, and hypertension shared by both NAFLD and CVD, and also there is independent association of NAFLD with CVD because of risk factors such as insulin resistance, systemic inflammation, and atherogenic dyslipidemia. While there is abundant literature on association of NAFLD with CVD, there is sparse literature regarding the screening for CVD in patients with NAFLD. In the current review article, we discuss as to which patients with NAFLD to screen and how to screen for CVD.

Cardiac stress testing and coronary artery disease in liver transplantation candidates: Meta-analysis

AIM

To evaluate the diagnostic value of dobutamine stress echocardiography (DSE) and myocardial perfusion scintigraphy (MPS) in predicting coronary artery disease (CAD) in cirrhotic patients listed for liver transplantation (LT), using invasive coronary angiography (ICA) as gold-standard.

METHODS

Retrieval of studies was based on Medical Subject Headings and Health Sciences Descriptors, which were combined using Boolean operators. Searches were run on the electronic databases Scopus, Web of Science, EMBASE, MEDLINE (PubMed), BIREME (Biblioteca Regional de Medicina), LILACS (Latin American and Caribbean Health Sciences Literature), Cochrane Library for Systematic Reviews and Opengray.eu. There was no language or date of publication restrictions. The reference lists of the studies retrieved were searched manually.

RESULTS

The search strategy retrieved 322 references for DSE and 90 for MPS. In the final analysis, 10 references for DSE and 10 for MPS were included. Pooled sensitivity was 28% and 61% for DSE and MPS and specificity was 82% and 74%, for diagnosis of CAD using ICA as gold-standard, respectively.

CONCLUSION

DSE and MPS do not have adequate sensitivity for determination of whether CAD is present, despite having significant specificity.

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.

Liver Transplantation in Patients With Cardiac Disease

Liver transplantation (LT) is a unique surgical procedure that has major hemodynamic and cardiovascular implications. Recently, there has been significant interest focused on cardiovascular issues that affect LT patients in all phases of the perioperative period. The preoperative cardiac evaluation is a major step in the selection of LT candidates. LT candidates are aging in concordance with the general population; cardiovascular disease and their risk factors are highly associated with older age. Underlying cardiovascular disease has the potential to affect outcomes in LT patients and has a major impact on candidate selection. The prolonged hemodynamic and metabolic instability during LT may contribute to adverse outcomes, especially in patients with underlying cardiovascular disease. Cardiovascular events are not unusual during LT; transplant anesthesiologists must be prepared for these events. Advanced cardiovascular monitoring techniques and treatment modalities are now routinely used during LT. Postoperative cardiovascular complications are common in both the early and late posttransplant periods. The impact of cardiac complications on posttransplant mortality is well recognized. Emerging knowledge regarding cardiovascular disease in LT patients and its impact on posttransplant outcomes will have an important role in guiding the future perioperative management of LT patients.

Evaluation of coronary artery disease in potential liver transplant recipients

Improvements in the management of patients undergoing liver transplantation (LT) have resulted in a significant increase in survival in recent years. Cardiac disease is now the leading cause of early mortality, and the stress of major surgery, hemodynamic shifts, and the possibilities of hemorrhage or reperfusion syndrome require the recipient to have good baseline cardiac function. The prevalence of coronary artery disease (CAD) is increasing in LT candidates, especially in those with nonalcoholic fatty liver disease. In assessing LT recipients, we suggest a management paradigm of "quadruple assessment" to include (1) history, examination, and electrocardiogram; (2) transthoracic echocardiogram; (3) functional testing; and (4) where appropriate, direct assessment of CAD. The added value of functional testing, such as cardiopulmonary exercise testing, has been shown to be able to predict posttransplant complications independently of the presence of CV disease. This approach gives the assessment team the greatest chance of detecting and preventing complications related to CAD. Liver Transplantation 23 386-395 2017 AASLD.

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.

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

Coronary artery disease (CAD) is prevalent in patients with end-stage liver disease and associated with poor outcomes when undergoing orthotopic liver transplantation (OLT); however, noninvasive screening for CAD in this population is less sensitive. In an attempt to identify redundancy, we reviewed our experience among patients undergoing CAD screening as part of their OLT evaluation between May 2009 and February 2014. Demographic, clinical, and procedural characteristics were analyzed. Of the total number of screened patients (n = 132), initial screening was more common via stress testing (n = 100; 75.8%) than coronary angiography (n = 32; 24.2%). Most with initial stress testing underwent angiography (n = 52; 39.4%). Among those undergoing angiography, CAD was common (n = 31; 23.5%). Across the entire cohort the number of traditional risk factors was linearly associated with CAD, and those with two or more risk factors were found to have CAD by angiography 50% of the time (OR 1.92; CI 1.07–3.44, p = 0.026). Our data supports that CAD is prevalent among pre-OLT patients, especially among those with 2 or more risk factors. Moreover, we identified a lack of uniformity in practice and the need for evidence-based and standardized screening protocols.

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

Cardiac risk assessment prior to kidney and liver transplantation is controversial. Given the paucity of available organs, selecting appropriate recipients with favorable short- and long-term cardiovascular risk profile is crucial. Using noninvasive cardiac imaging tools to guide cardiovascular risk assessment and management can also be challenging and controversial. In this article, we address the burden of coronary artery disease among kidney and liver transplant candidates and review the literature pertaining to the diagnostic accuracy and the prognostic value of noninvasive cardiac imaging techniques in this population.

Myocardial perfusion imaging is an effective screening test for coronary artery disease in liver transplant candidates

A reliable screening test for coronary artery disease (CAD) in liver transplant (LT) candidates with end-stage liver disease is essential because a high percentage of perioperative mortality and morbidity is CAD-related. In this study, the effectiveness of myocardial perfusion imaging (MPI) for identification of significant CAD in LT candidates was evaluated. Records of 244 patients meeting criteria for MPI were evaluated: 74 met inclusion criteria; 40 had a positive MPI and cardiology follow-up; 27 had a negative MPI and underwent LT; and seven had a negative MPI and then had coronary angiography or a significant cardiac event. A selective MPI interpretation strategy was established where MPI-positive patients were divided into high, intermediate, and low CAD risk groups. The overall incidence of CAD in this study population was 5.1% and our strategy resulted in PPV 20%, NPV 94%, sensitivity 80%, and specificity 50% for categorizing CAD risk. When applied only to the subset of patients categorized as high CAD risk, the strategy was more effective, with PPV 67%, NPV 97%, sensitivity 80%, and specificity 94%. We determined that renal dysfunction was an independent predictive factor for CAD (p < 0.0001, odds ratio = 8.1), and grades of coronary occlusion correlated significantly with chronic renal dysfunction (p = 0.0079).

Transradial cardiac catheterization in liver transplant candidates

Transradial (TR) cardiac catheterization is effective and offers lower rates of vascular complications and bleeding compared with transfemoral cardiac catheterization. We sought to describe the safety and feasibility of TR cardiac catheterization in liver transplant candidates (LTCs). We retrospectively reviewed 1,071 consecutive cases of TR cardiac catheterization in 1,045 patients from May 2008 to December 2011 at a single institution. The primary end point was radial approach failure. Ten percent of TR cases (n = 107) were performed in LTCs and 90% (n = 964) were performed in non-LTCs. The LTC group had lower rates of cardiovascular diseases and cardiovascular risk factors. The LTC group had a significantly lower platelet count (75,000 vs 237,000/mm(3), p <0.01), higher international normalized ratio (1.7 vs 1.1, p <0.01), and lower mean arterial pressure (78 vs 89 mm Hg, p <0.01). The mean Model for End-Stage Liver Disease score was 21 in LTCs. Percutaneous coronary interventions were performed in 4% of LTCs and 15% of non-LTCs (p <0.01). The radial approach failure rate was 10% in LTCs and 7% in non-LTCs (p = 0.15). In conclusion, radial approach failure was similar between the LTC and non-LTC groups. Despite significant differences in platelet count and international normalized ratio, there was no difference in the incidence of adverse events between the groups, suggesting that TR cardiac catheterization is safe and effective in LTCs.