Impact of Cirrhotic Cardiomyopathy Diagnosed According to Different Criteria on Patients with Cirrhosis Awaiting Liver Transplantation: A Retrospective Cohort Study

Cardiomyopathy in cirrhosis: From pathophysiology to clinical care

Cirrhotic cardiomyopathy (CCM) is defined as systolic or diastolic dysfunction in the absence of prior heart disease or another identifiable cause in patients with cirrhosis, in whom it is an important determinant of outcome. Its underlying pathogenic/pathophysiological mechanisms are rooted in two distinct pathways: 1) factors associated with portal hypertension, hyperdynamic circulation, gut bacterial/endotoxin translocation and the resultant inflammatory phenotype; 2) hepatocellular insufficiency with altered synthesis or metabolism of substances such as proteins, lipids, carbohydrates, bile acids and hormones. Different criteria have been proposed to diagnose CCM; the first in 2005 by the World Congress of Gastroenterology, and more recently in 2019 by the Cirrhotic Cardiomyopathy Consortium. These criteria mainly utilised echocardiographic evaluation, with the latter refining the evaluation of diastolic function and integrating global longitudinal strain into the evaluation of systolic function, an important addition since the haemodynamic changes that occur in advanced cirrhosis may lead to overestimation of systolic function by left ventricular ejection fraction. Advances in cardiac imaging, such as cardiac magnetic resonance imaging and the incorporation of an exercise challenge, may help further refine the diagnosis of CCM. Over recent years, CCM has been shown to contribute to increased mortality and morbidity after major interventions, such as liver transplantation and transjugular intrahepatic portosystemic shunt insertion, and to play a pathophysiologic role in the genesis of hepatorenal syndrome. In this review, we discuss the pathogenesis/pathophysiology of CCM, its clinical implications, and the role of cardiac imaging modalities including MRI. We also compare diagnostic criteria and review the potential diagnostic role of electrocardiographic QT prolongation. At present, no definitive medical therapy exists, but some promising potential treatment strategies for CCM are reviewed.

Left atrial strain and ventricular global longitudinal strain in cirrhotic patients using the new criteria of Cirrhotic Cardiomyopathy Consortium

BACKGROUND

The new criteria of Cirrhotic Cardiomyopathy Consortium (CCC) propose the use of left ventricular global longitudinal strain (LV-GLS) for evaluation of systolic function in patients with cirrhosis. The aim of this study was to evaluate LV-GLS and left atrial (LA) strain in association with the severity of liver disease and to assess the characteristics of cirrhotic cardiomyopathy (CCM).

METHODS

One hundred and thirty-five cirrhotic patients were included. Standard echocardiography and speckle tracking echocardiography (2D-STE) were performed, and dual X-ray absorptiometry was used to quantify the total and regional fat mass. CCM was defined, based on the criteria of CCC, as having advanced diastolic dysfunction, left ventricular ejection fraction ≤50% and/or a GLS <18%.

RESULTS

LV-GLS lower or higher than the absolute mean value (22.7%) was not associated with mortality (logrank, p = 0.96). LV-GLS was higher in patients with Model for end stage liver disease (MELD) score ≥15 compared to MELD score <15 (p = 0.004). MELD score was the only factor independently associated with systolic function (LV-GLS <22.7% vs. ≥22.7%) (Odds Ratio:1.141, p = 0.032). Patients with CCM (n = 11) had higher values of estimated volume of visceral adipose tissue compared with patients without CCM (median: 735 vs. 641 cm3 , p = 0.039). On multivariable Cox regression analysis, MELD score [Hazard Ratio (HR):1.26, p < 0.001] and LA reservoir strain (HR:0.96, p = 0.017) were the only factors independently associated with the outcome.

CONCLUSION

In our study, absolute LV-GLS was higher in more severe liver disease, and LA reservoir strain was significantly associated with the outcome in patients with end-stage liver disease.

Dysregulated Calcium Handling in Cirrhotic Cardiomyopathy

Cirrhotic cardiomyopathy is a syndrome of blunted cardiac systolic and diastolic function in patients with cirrhosis. However, the mechanisms remain incompletely known. Since contractility and relaxation depend on cardiomyocyte calcium transients, any factors that impact cardiac contractile and relaxation functions act eventually through calcium transients. In addition, calcium transients play an important role in cardiac arrhythmias. The present review summarizes the calcium handling system and its role in cardiac function in cirrhotic cardiomyopathy and its mechanisms. The calcium handling system includes calcium channels on the sarcolemmal plasma membrane of cardiomyocytes, the intracellular calcium-regulatory apparatus, and pertinent proteins in the cytosol. L-type calcium channels, the main calcium channel in the plasma membrane of cardiomyocytes, are decreased in the cirrhotic heart, and the calcium current is decreased during the action potential both at baseline and under stimulation of beta-adrenergic receptors, which reduces the signal to calcium-induced calcium release. The study of sarcomere length fluctuations and calcium transients demonstrated that calcium leakage exists in cirrhotic cardiomyocytes, which decreases the amount of calcium storage in the sarcoplasmic reticulum (SR). The decreased storage of calcium in the SR underlies the reduced calcium released from the SR, which results in decreased cardiac contractility. Based on studies of heart failure with non-cirrhotic cardiomyopathy, it is believed that the calcium leakage is due to the destabilization of interdomain interactions (dispersion) of ryanodine receptors (RyRs). A similar dispersion of RyRs may also play an important role in reduced contractility. Multiple defects in calcium handling thus contribute to the pathogenesis of cirrhotic cardiomyopathy.

Impact of cardiac dysfunction on morbidity and mortality in liver transplant candidates

The prognostic role of cardiac dysfunction in cirrhotic patients is increasingly recognised. We studied its impact on morbidity and mortality before and after liver transplantation (LT) including development of post-transplant cardiovascular disease (CVD). In this retrospective study, cirrhotic patients who underwent LT assessment from January 2010 to December 2020 were reviewed. Demographics, cardiac investigations and clinical course were analysed to identify prevalence of cardiac dysfunction and its role in LT outcomes. Survival analysis was performed using Cox proportional hazard regression modelling, with LT as a time-varying covariate and as an interaction variable with cardiac dysfunction. 308 patients (70% male) were studied. The median (interquartile range) age at LT assessment was 56 (12) years. Cardiac dysfunction was found in 178 (58%) patients (diastolic, 169; systolic, 26; both, 17) and was significantly associated with hepatorenal syndrome/acute kidney injury and peri- and post-transplant morbidity (adjusted odds ratio [aOR] 1.94, 95%CI 1.06-3.52, p < 0.001; aOR 2.01, 95%CI 1.06-3.82, p = 0.033; aOR 1.9, 95%CI 1.01-3.65, p = 0.023, respectively). Cardiac dysfunction was not associated with mortality before (adjusted hazard ratio [aHR] 1.01, 95% CI 0.99-1.01) or after LT (aHR 0.74, 95% CI 0.4-1.05. Post-transplant CVD (61% cardiac failure) occurred in 36 patients and there was no significant association with cardiac dysfunction (p = 0.11). Cardiac dysfunction was common in LT candidates and was significantly associated with morbidity before and after LT. Studies on the role of advanced echocardiographic parameters to improve diagnosis of cardiac dysfunction and optimise LT outcomes are needed. This article is protected by copyright. All rights reserved.