Acute non-selective beta-adrenergic blockade reduces prolonged frequency-adjusted Q-T interval (QTc) in patients with cirrhosis

Therapies for Cirrhotic Cardiomyopathy: Current Perspectives and Future Possibilities

Cirrhotic cardiomyopathy (CCM) is defined as cardiac dysfunction associated with cirrhosis in the absence of pre-existing heart disease. CCM manifests as the enlargement of cardiac chambers, attenuated systolic and diastolic contractile responses to stress stimuli, and repolarization changes. CCM significantly contributes to mortality and morbidity in patients who undergo liver transplantation and contributes to the pathogenesis of hepatorenal syndrome/acute kidney injury. There is currently no specific treatment. The traditional management for non-cirrhotic cardiomyopathies, such as vasodilators or diuretics, is not applicable because an important feature of cirrhosis is decreased systemic vascular resistance; therefore, vasodilators further worsen the peripheral vasodilatation and hypotension. Long-term diuretic use may cause electrolyte imbalances and potentially renal injury. The heart of the cirrhotic patient is insensitive to cardiac glycosides. Therefore, these types of medications are not useful in patients with CCM. Exploring the therapeutic strategies of CCM is of the utmost importance. The present review summarizes the possible treatment of CCM. We detail the current status of non-selective beta-blockers (NSBBs) in the management of cirrhotic patients and discuss the controversies surrounding NSBBs in clinical practice. Other possible therapeutic agents include drugs with antioxidant, anti-inflammatory, and anti-apoptotic functions; such effects may have potential clinical application. These drugs currently are mainly based on animal studies and include statins, taurine, spermidine, galectin inhibitors, albumin, and direct antioxidants. We conclude with speculations on the future research directions in CCM treatment.

Cirrhotic cardiomyopathy: a subject that's always topical

Cirrhosis is the final stage in the development of hepatic fibrosis in chronic liver disease. It is associated with major hemodynamic disturbances defining the hyperdynamic circulation and may be complicated by specific cardiac involvement or cirrhotic cardiomyopathy which is a silent clinical condition that typically remains asymptomatic until the late stages of liver disease. Recently, new criteria defining CC, based on modern concepts and knowledge of heart failure, have been proposed. Despite knowledge of the main mechanisms behind this entity, there is no specific treatment available for cirrhotic cardiomyopathy. The management approach for symptomatic cardiomyopathy in cirrhotic patients is similar to that for left ventricular failure in non-cirrhotic individuals.

Corrected QT interval in cirrhosis: A systematic review and meta-analysis

BACKGROUND

Corrected QT (QTc) interval is prolonged in patients with liver cirrhosis and has been proposed to correlate with the severity of the disease. However, the effects of sex, age, severity, and etiology of cirrhosis on QTc have not been elucidated. At the same time, the role of treatment, acute illness, and liver transplantation (Tx) remains largely unknown.

AIM

To determine the mean QTc in patients with cirrhosis, assess whether QTc is prolonged in patients with cirrhosis, and investigate whether QTc is affected by factors such as sex, age, severity, etiology, treatment, acute illness, and liver Tx.

METHODS

In the present systematic review and meta-analysis, the searching protocol "{[QTc] OR [QT interval] OR [QT-interval] OR [Q-T syndrome]} AND {[cirrhosis] OR [Child-Pugh] OR [MELD]}" was applied in PubMed, EMBASE, and Google Scholar databases to identify studies that reported QTc in patients with cirrhosis and published after 1998. Seventy-three studies were considered eligible. Data concerning first author, year of publication, type of study, method used, sample size, mean age, female ratio, alcoholic etiology of cirrhosis ratio, Child-Pugh A/B/C ratio, mean model for end-stage liver disease (MELD) score, treatment with β-blockers, episode of acute gastrointestinal bleeding, formula for QT correction, mean pulse rate, QTc in patients with cirrhosis and controls, and QTc according to etiology of cirrhosis, sex, Child-Pugh stage, MELD score, and liver Tx status (pre-Tx/post-Tx) were retrieved. The Newcastle-Ottawa quality assessment scale appraised the quality of the eligible studies. Effect estimates, expressed as proportions or standardized mean differences, were combined using the random-effects, generic inverse variance method of DerSimonian and Laird. Subgroup, sensitivity analysis, and meta-regressions were applied to assess heterogeneity. The study has been registered in the PROSPERO database (CRD42023416595).

RESULTS

QTc combined mean in patients with cirrhosis was 444.8 ms [95% confidence interval (CI): 440.4-449.2; P < 0.001 when compared with the upper normal limit of 440 ms], presenting high heterogeneity (I2 = 97.5%; 95%CI: 97.2%-97.8%); both Egger's and Begg's tests showed non-significance. QTc was elongated in patients with cirrhosis compared with controls (P < 0.001). QTc was longer in patients with Child-Pugh C cirrhosis when compared with Child-Pugh B and A (P < 0.001); Child-Pugh B patients presented longer QTc when compared with Child-Pugh A patients (P = 0.003). The MELD score was higher in patients with cirrhosis with QTc > 440 ms when compared with QTc ≤ 440 ms (P < 0.001). No correlation of QTc with age (P = 0.693), sex (P = 0.753), or etiology (P = 0.418) was detected. β-blockers shortened QTc (P< 0.001). QTc was prolonged during acute gastrointestinal bleeding (P = 0.020). Tx tended to improve QTc (P < 0.001). No other sources of QTc heterogeneity were revealed.

CONCLUSION

QTc is prolonged in cirrhosis independently of sex, age, and etiology but is correlated with severity and affected by β-blockers and acute gastrointestinal bleeding. QTc is improved after liver Tx.

Diagnosis and Management of Cirrhotic Cardiomyopathy

BACKGROUND

Cirrhotic cardiomyopathy refers to the structural and functional changes in the heart leading to either impaired systolic, diastolic, electrocardiographic, and neurohormonal changes associated with cirrhosis and portal hypertension. Cirrhotic cardiomyopathy is present in 50% of patients with cirrhosis and is clinically seen as impaired contractility, diastolic dysfunction, hyperdynamic circulation, and electromechanical desynchrony such as QT prolongation. In this review, we will discuss the cardiac physiology principles underlying cirrhotic cardiomyopathy, imaging techniques such as cardiac magnetic resonance imaging and scintigraphy, cardiac biomarkers, and newer echocardiographic techniques such as tissue Doppler imaging and speckle tracking, and emerging treatments to improve outcomes.

METHODS

We reviewed available literature from MEDLINE for randomized controlled trials, cohort studies, cross-sectional studies, and real-world outcomes using the search terms "cirrhotic cardiomyopathy," "left ventricular diastolic dysfunction," "heart failure in cirrhosis," "liver transplantation," and "coronary artery disease".

RESULTS

Cirrhotic cardiomyopathy is associated with increased risk of complications such as hepatorenal syndrome, refractory ascites, impaired response to stressors including sepsis, bleeding or transplantation, poor health-related quality of life and increased morbidity and mortality. The evaluation of cirrhotic cardiomyopathy should also guide the feasibility of procedures such as transjugular intrahepatic portosystemic shunt, dose titration protocol of betablockers, and liver transplantation. The use of targeted heart rate reduction is of interest to improve cardiac filling and improve the cardiac output using repurposed heart failure drugs such as ivabradine. Liver transplantation may also reverse the cirrhotic cardiomyopathy; however, careful cardiac evaluation is necessary to rule out coronary artery disease and improve cardiac outcomes in the perioperative period.

CONCLUSION

More data are needed on the new diagnostic criteria, molecular and biochemical changes, and repurposed drugs in cirrhotic cardiomyopathy. The use of advanced imaging techniques should be incorporated in clinical practice.

Autonomic dysfunction is common in liver cirrhosis and is associated with cardiac dysfunction and mortality: prospective observational study

BACKGROUND

Although autonomic dysfunction has been shown to be associated with liver cirrhosis, the prevalence and prognostic implications are unclear. Abnormal heart rate variability (HRV), a measure of autonomic function, has not been well investigated in cirrhosis.

OBJECTIVE

To evaluate the prevalence of high-risk HRV parameters in a cohort of cirrhotic patients and their association with cardiac dysfunction and mortality.

DESIGN AND SETTING

Prospective observational study conducted in the Federal University of São Paulo.

METHOD

A cohort of 120 patients, comprising 17 healthy controls and 103 cirrhotic outpatients, was evaluated and followed for 10 months. HRV analysis was based on 24-hour Holter monitoring and defined using time-domain and frequency-domain parameters.

RESULTS

The HRV parameters were statistically lower in cirrhotic patients than in healthy subjects. High-risk HRV parameters were prevalent, such that 64% had at least one high-risk parameter. Time-domain parameters correlated with Child scores (P < 0.0001). In regression models, HRV parameters were independent predictors of diastolic dysfunction and mortality. During 10 months of follow-up, there were 11 deaths, all of patients with at least one high-risk HRV parameter. Kaplan-Meier analysis estimated low survival rates among patients with standard deviation of normal-to-normal RR intervals (SDNN) < 100.

CONCLUSION

Reduced HRV is prevalent in liver cirrhosis and is related to cardiac dysfunction, severity of liver disease and mortality. Abnormal high-risk HRV parameters are prevalent among cirrhotic patients and are also predictors of mortality. Our findings highlight the need for a more careful cardiac evaluation of cirrhotic patients.

β-blockers in advanced cirrhosis: More friend than enemy

Nonselective beta-adrenergic blocker (NSBB) therapy for the prevention of initial and recurrent gastrointestinal bleeding in cirrhotic patients with gastroesophageal varices has been used for the past four decades. NSBB therapy is considered the cornerstone of treatment for varices, and has become the standard of care. However, a 2010 study from the group that pioneered β-blocker therapy suggested a detrimental effect of NSBBs in decompensated cirrhosis, especially in patients with refractory ascites. Since then, numerous additional studies have incompletely resolved whether NSBBs are deleterious, although more recent evidence weighs against a harmful effect. The possibility of a "therapeutic window" has also been raised. We aimed to review the literature to analyze the pros and cons of using NSBBs in patients with cirrhosis, not only with respect to bleeding or mortality but also to other potential benefits and risks. β-blockers are highly effective in preventing first bleeding and recurrent bleeding. Furthermore, NSBBs improve congestion/ischemia of the gut mucosa, decrease intestinal permeability, and therefore indirectly alleviate systemic inflammation. β-blockers shorten the electrocardiographic prolonged QTc interval and may also decrease the incidence of hepatocellular carcinoma. On the other hand, the possibility of deleterious effects in cirrhosis has not been completely eliminated. NSBBs may be associated with an increased risk of portal vein thrombosis, although this could be correlational artifact. Overall, we conclude that β-blockers in cirrhosis are much more of a friend than enemy.

Cirrhotic Cardiomyopathy: The Interplay Between Liver and Cardiac Muscle. How Does the Cardiovascular System React When the Liver is Diseased?

It is widely known that liver cirrhosis, regardless of the etiologies is accompanied by severe hemodynamic changes. The principal pathophysiological mechanisms are the hyperdynamic circulation with increased cardiac output, heart rate along with reduced systemic vascular resistance. Thus, counteractive mechanisms may develop that eventually lead to systolic as well as diastolic dysfunction and rhythm disturbances, in order to keep a steady homeostasis in the human body.

Literally, blunted contractile responsiveness to physical or pharmacological stress, impaired diastolic relaxation and electrophysiological changes, primarily QT interval prolongation, do occur progressively in a cirrhotic patient with no known preexisting cardiac disease. This condition is identified as cirrhotic cardiomyopathy (CCM), an entity different from that seen in alcoholic cardiac muscle disease.

For the past decades, clinicians did study and attempt to understand the pathophysiology and clinical significance of this process. Indeed, various factors have been identified acting at the molecular and cellular level.

Electrocardiography, echocardiography and various serum biomarkers are the main tools that help healthcare practitioners to point to the correct diagnosis.

Noteworthy, the subjects that suffer from cirrhotic cardiomyopathy may progress to heart failure during invasive procedures such as surgery, insertion of a transjugular intrahepatic portosystemic shunting (TIPS) and liver transplantation. Besides, several studies have illustrated that CCM is a contributing factor, or even a precipitant, of hepatorenal syndrome (HRS), a conceivable reversible kidney failure in patients with liver cirrhosis and ascites.

The treatment is the same as it is in the patients with liver cirrhosis and heart failure and there is no particular treatment for cirrhotic cardiomyopathy. Hence, it is of utmost importance to clearly comprehend the pathophysiology of this disease in order to design more accurate diagnostic tools and definitive treatments in a way to prevent the complications of cirrhosis and overt heart failure.

The objective of this review is to describe in a comprehensive way the pathological alterations that occur in the cardiovascular system of cirrhotic patients. It will also point the limitations that remain in the diagnosis and treatment strategies and more importantly, this review will alert the clinicians in the modern era to further observe and record additional pathological changes in this subset of patients.

Effect of QT interval prolongation on cardiac arrest following liver transplantation and derivation of a risk index

Liver transplantation (LT) has a 4-fold higher risk of periprocedural cardiac arrest and ventricular arrhythmias (CA/VAs) compared with other noncardiac surgeries. Prolongation of the corrected QT interval (QTc) is common in patients with liver cirrhosis. Whether it is associated with an increased risk of CA/VAs following LT is unclear. Rates of 30-day CA/VAs post-LT were assessed in consecutive adults undergoing LT between 2010 and 2017. Pretransplant QTc was measured by a cardiologist blinded to clinical outcomes. Among 408 patients included, CA/VAs occurred in 26 patients (6.4%). QTc was significantly longer in CA/VA patients (475 ± 34 vs 450 ± 34 ms, P < .001). Optimal QTc cut-off for prediction of CA/VAs was ≥480 ms. After adjustment, QTc ≥480 ms remained the strongest predictor for the occurrence of CA/VAs (odds ratio [OR] 5.2, 95% confidence interval [CI] 2.2-12.6). A point-based cardiac arrest risk index (CARI) was derived with the bootstrap method for yielding optimism-corrected coefficients (2 points: QTc ≥480, 1 point: Model for End-Stage Liver Disease [MELD] ≥30, 1 point: age ≥65, and 1 point: male). CARI score ≥3 demonstrated moderate discrimination (c-statistic 0.79, optimism-corrected c-statistic 0.77) with appropriate calibration. QTc ≥480 ms was associated with a 5-fold increase in the risk of CA/VAs. The CARI score may identify patients at higher risk of these events. Whether heightened perioperative cardiac surveillance, avoidance of QT prolonging medications, or beta blockers could mitigate the risk of CA/VAs in this population merits further study.

QTc prolongation in patients of cirrhosis and its relation with disease severity: An observational study from a rural teaching hospital

Introduction:

Cirrhotic cardiomyopathy is characterised by increased baseline cardiac output, systolic and diastolic dysfunction, diminished cardiovascular response to stressful stimuli and electrophysiological abnormalities in patients of cirrhosis in the absence of any underlying cardiac disease. QTc prolongation has been described as a common electrocardiographic abnormality in cirrhosis patients.

Aims and Objectives:

This study was done to evaluate the prevalence of QTc changes in patients of cirrhosis coming to a rural tertiary care centre and to analyse its correlation with disease severity.

Materials and Methods:

The present study was conducted on 100 patients suffering from cirrhosis of liver presented to the department of medicine. Around 100 age and sex-matched individuals were recruited as controls. The Child-Pugh score was used to determine the disease severity in cirrhosis patients. Standard 12-lead ECG was recorded in all cases and controls.

Results:

Prolongation of QTc interval on ECG was observed in the majority (80%) of cirrhosis patients and it was significantly higher as compared to the healthy controls (P <0.01). The prolongation of QTc was significantly associated with the duration of disease (P <0.05) and disease severity as measured by the Child-Pugh score (P <0.01).

Conclusion:

QTc prolongation on ECG may be an early marker of cardiac involvement in patients of cirrhosis and is significantly associated with disease severity.

Cirrhotic Cardiomyopathy

PURPOSE OF REVIEW

Cirrhotic cardiomyopathy is a syndrome of depressed cardiac function in patients with cirrhosis. We aimed to review the historical background, pathophysiology and pathogenesis, diagnostic definitions, clinical relevance, and management of this syndrome.

RECENT FINDINGS

An inflammatory phenotype underlies the pathogenesis: gut bacterial translocation with endotoxemia stimulates cytokines and cardiodepressant factors, such as nitric oxide and endocannabinoids. Cardiomyocyte plasma membrane biochemical and biophysical changes also play a pathogenic role. These factors lead to impaired beta-adrenergic function. Proposed new echocardiographic criteria for the diagnosis of cirrhotic cardiomyopathy include systolic global longitudinal strain and indices of diastolic dysfunction. Cardiac dysfunction participates in the pathogenesis of hepatorenal syndrome and increased morbidity/mortality of cirrhotic patients to hemorrhage, infection, and surgery, including liver transplantation. There is no specific treatment, although β-adrenergic blockade and supportive management have been proposed, but it needs further study. Cirrhotic cardiomyopathy is a clinically relevant syndrome afflicting patients with established cirrhosis. Optimum management remains unclear, and further study is needed in this area.

Prevalence of prolonged QT interval in patients with HCV-related chronic liver disease

Background

Hepatitis C virus (HCV) is a common disease in Egypt with a high socioeconomic burden and extra-hepatic manifestations as QT prolongation, but previous studies included mainly patients with advanced liver disease, so in this study, we aimed to delineate the prevalence of QT prolongation in early-stage HCV patients.

Results

The study included 874 HCV patients with early cirrhosis; in Child’s class A, 57 (6.5%) patients had prolonged QT interval corrected (QTc). There was significant higher proportion of cirrhotic patients in the prolonged QTc group (31.6%) vs. in the normal QTc group (11.5%). QTc was 424.39 ± 36.6 vs. 411.51 ± 32.89 ms in cirrhotic and non-cirrhotic patients, respectively (P, 0.001). There was significant higher proportion of Fibrosis 4 (FIB-4) ≥ 1.45 score in the prolonged QTc (77.2%) vs. in the normal QTc group (56.8%) (P, 0.003). QTc interval was 417.76 ± 34.12 ms in patients with FIB-4 score ≥ 1.45 vs. 406.78 ± 31.95 ms in those with FIB-4 < 1.45 (P, < 0.001). FIB-4 score value of 2.108 predicted prolonged QTc with a sensitivity of 63.2% and a specificity of 64.5% (P, < 0.001). Twenty-four patients of long QTc group sent ECGs after HCV eradication, and 19 patients (79%) showed QTc normalization.

Conclusions

HCV is associated with QTc prolongation even in patients with early chronic liver disease stages without significant fibrosis. Also, it is related to the degree of fibrosis and cirrhosis. At a cutoff value of 2.108, FIB-4 score can predict prolonged QTc. HCV eradication is associated with a high incidence of QTc normalization.

An update on cirrhotic cardiomyopathy

Cirrhosis with portal hypertension and related complications are associated with a high mortality. Excess of circulating vasodilators and cardiodepressive substances lead to a hyperdynamic circulation with changed myocardial structure and function. The entity cirrhotic cardiomyopathy seems to be involved in different aspects of hepatic decompensation, which focuses on new targets of treatment. Areas covered: This review deals with contemporary aspects of cirrhotic cardiomyopathy, and the literature search was undertaken by PubMed with 'cirrhotic' and 'cardiomyopathies' as MeSH Terms. Cirrhotic cardiomyopathy is defined as the presence of systolic and diastolic dysfunction and electrophysiological abnormalities. The diagnosis is based on contemporary Doppler/Echocardiography measurements or quantitative magnetic resonance imaging. Cirrhotic cardiomyopathy is independent of the etiology of the liver disease but related to severity and survival. Expert commentary: The outcome of invasive procedures and liver transplantation is influenced by the presence of cardiac dysfunction. Therefore, a cautious cardiac evaluation should be included in the patient evaluation prior to liver transplantation. Liver transplantation ameliorates most of the abnormalities seen in cirrhotic cardiomyopathy, but no specific treatment can yet be recommended.

Q-T Interval Prolongation in Patients with Liver Cirrhosis

Liver cirrhosis (LC) is the end stage of chronic liver disease characterized by the appearance of extensive fibrosis and regeneration nodes associated with hepatocyte necrosis in liver but also by the reshuffling of hepatic architecture. The triad consisting of hepatic parenchymal necrosis, regeneration and scarring is always present regardless of the type of clinical manifestation. The Child-Pugh-Turcotte classification dates back more than 30 years and has been widely used in diagnosing and assessing the severity of liver cirrhosis. This is preferred due to a low degree of complexity and a good predictive value. Prolongation of the QT interval on the electrocardiogram is common, with a prevalence exceeding 60% in patients with advanced stage of cirrhosis. In these cases, beta blockers and antiarrhythmics should be avoided or used with caution and with close QT interval monitoring. Changes in heart rate and Q-T interval are new entities in cirrhosis complications. A prolonged Q-T interval in chronic liver disease could lead to ventricular arrhythmias and sudden death. There is no report on heart rate and Q-T interval disorders in our area.

The pathophysiology of arterial vasodilatation and hyperdynamic circulation in cirrhosis

Patients with cirrhosis and portal hypertension often develop complications from a variety of organ systems leading to a multiple organ failure. The combination of liver failure and portal hypertension results in a hyperdynamic circulatory state partly owing to simultaneous splanchnic and peripheral arterial vasodilatation. Increases in circulatory vasodilators are believed to be due to portosystemic shunting and bacterial translocation leading to redistribution of the blood volume with central hypovolemia. Portal hypertension per se and increased splanchnic blood flow are mainly responsible for the development and perpetuation of the hyperdynamic circulation and the associated changes in cardiovascular function with development of cirrhotic cardiomyopathy, autonomic dysfunction and renal dysfunction as part of a cardiorenal syndrome. Several of the cardiovascular changes are reversible after liver transplantation and point to the pathophysiological significance of portal hypertension. In this paper, we aimed to review current knowledge on the pathophysiology of arterial vasodilatation and the hyperdynamic circulation in cirrhosis.

Modeling young and adult patients with cirrhosis through a three element windkessel (WK3e)

INTRODUCTION

Measurement of hemodynamic parameters constitutes an important tool in the management of patients with cirrhosis. In recent years, non-invasive measurements have gain attention, due to the potential complications associated to invasive procedures.

OBJECTIVE

To characterize the hemodynamic alterations of cirrhosis in young and adult subjects, through a three element windkessel (WK3e).

METHODS

Individuals were divided in three age groups: Young Healthy group (control, CG), Young Cirrhotic Group (YCG) and Adult Cirrhotic Group (ACG). A Finapres® Nova device was used to obtain cardiac output (CO), heart rate and arterial blood pressure. Systemic arterial compliance (C), peripheral resistance (R) and characteristic impedance (Zc) were also provided. Effective arterial elastance (Ea), left ventricular work (LVW), input impedance, efficiency and model cutoff frequency (WK_CF) were assessed based on the provided data.

RESULTS

CO resulted to be higher in ACG than in CG and YGC. LVW, C and WKcf showed an increase, while R and Ea showed a decrease. However, this behavior was not observed in YCG.

CONCLUSION

Cirrhosis was properly modeled in young and adult subjects in terms of non-invasive measurements and a WK3e.

QT prolongation is associated with increased mortality in end stage liver disease

AIM

To determine the prevalence of QT prolongation in a large series of end stage liver disease (ESLD) patients and its association to clinical variables and mortality.

METHODS

The QT interval was measured and corrected for heart rate for each patient, with a prolonged QT cutoff defined as QT > 450 ms for males and QT > 470 ms for females. Multiple clinical variables were evaluated including sex, age, serum sodium, international normalized ratio, creatinine, total bilirubin, beta-blocker use, Model for End-Stage Liver Disease (MELD), MELD-Na, and etiology of liver disease.

RESULTS

Among 406 ESLD patients analyzed, 207 (51.0%) had QT prolongation. The only clinical variable associated with QT prolongation was male gender (OR = 3.04, 95%CI: 2.01-4.60, P < 0.001). During the study period, 187 patients (46.1%) died. QT prolongation was a significant independent predictor of mortality (OR = 1.69, 95%CI: 1.03-2.77, P = 0.039). In addition, mortality was also associated with viral etiology of ESLD, elevated MELD score and its components (P < 0.05 for all). No significant reversibility in the QT interval was seen after liver transplantation.

CONCLUSION

QT prolongation was commonly encountered in an ESLD population, especially in males, and served as a strong independent marker for increased mortality in ESLD patients.

Cirrhotic Multiorgan Syndrome

Patients with cirrhosis and portal hypertension are at an increased risk of the development of circulatory dysfunction that may potentially result in multiple organ failure. Apart from the liver, this may involve the heart, lungs, kidneys, the immune system, the adrenal glands, and other organ systems. As the disease progresses, the circulation becomes hyperdynamic, and signs of cardiac, pulmonary, and renal dysfunction are observed, in addition to reduced survival. Infections and an altered cardiac function known as cirrhotic cardiomyopathy may be precipitators for the development of other complications such as hepatorenal syndrome. In patients with chronic organ dysfunction, various precipitating events may induce an acute-on-chronic renal failure and acute-on-chronic liver failure that negatively affect the prognosis. Future research on the pathophysiologic mechanisms of the complications and the precipitating factors is essential to understand the basics of the treatment of these challenging conditions. The aim of the present review is to focus on the development and precipitating factors of various organ failures in patients with decompensated cirrhosis.

Cirrhotic cardiomyopathy: review of pathophysiology and treatment

Cirrhotic cardiomyopathy is a cardiac condition observed in patients with cirrhotic regardless of the etiologies. It is characterized by the impaired systolic response to physical stress, diastolic dysfunction, and electrophysiological abnormalities, especially QT interval prolongation. Its pathophysiology and clinical significance has been a focus of various researchers for the past decades. The impairment of β-adrenergic receptor, the increase in endogenous cannabinoids, the presence of cardiosuppressants such as nitric oxide and inflammatory cytokines are the proposed mechanisms of systolic dysfunction. The activation of cardiac renin-angiotensin system and salt retention play the role in the development of cardiac hypertrophy and impaired diastolic function. QT interval prolongation, which is observed in 40-50 % of cirrhotic patients, occurs as a result of the derangement in membrane fluidity and ion channel defect. The increased recognition of this disease will prevent the complications of overt heart failure after procedures such as transjugular intrahepatic portosystemic shunt (TIPS) and liver transplantation. Better understandings of the pathogenesis and pathology of cirrhotic cardiomyopathy is crucial in developing more accurate diagnostic tools and specific treatments of this condition.

QT interval prolongation associated with low magnesium in chronic alcoholics

BACKGROUND

Alcoholism is a psychoactive drug-dependence with high prevalence throughout the world. Alcoholism has already been shown to be associated with electrical heart disorders, such as QT interval prolongation. Long QT, rare among healthy individuals (0.0017-0.31%), can trigger tachyarrhythmias and sudden death and might be caused by alcohol consumption itself and the resulting hypomagnesaemia.

METHODS

This case-control study assessed active alcoholics and alcoholics who have been abstinent for at least seven days to compare changes in electrocardiographic, clinical and laboratory analyses among groups.

RESULTS

A total of 166 alcoholics were evaluated, of which 62 were active and 104 abstinent alcoholics. Long QT was more prevalent among active alcoholics compared to abstinent alcoholics (16% vs. 2%, respectively, odds ratio (OR) 9.81, p=0.011), as was hypomagnesaemia (23% vs. 10%, OR 3.11, p=0.013). Serum magnesium levels were inversely proportional to the length of the corrected QT interval among active alcoholics (β=-35.1ms, p=0.005).

CONCLUSIONS

Active chronic alcoholics exhibited a higher association of long QT and hypomagnesaemia. Low serum magnesium levels were predictive of QT interval prolongation. Because the above changes potentially trigger fatal arrhythmias, it is of fundamental importance to consider the diagnostic possibility by routinely requesting electrocardiograms and serum magnesium level assessment during the treatment of chronic alcoholic patients.

Cirrhotic cardiomyopathy: review of pathophysiology and treatment

Cirrhotic cardiomyopathy is a cardiac condition observed in patients with cirrhotic regardless of the etiologies. It is characterized by the impaired systolic response to physical stress, diastolic dysfunction, and electrophysiological abnormalities, especially QT interval prolongation. Its pathophysiology and clinical significance has been a focus of various researchers for the past decades. The impairment of β-adrenergic receptor, the increase in endogenous cannabinoids, the presence of cardiosuppressants such as nitric oxide and inflammatory cytokines are the proposed mechanisms of systolic dysfunction. The activation of cardiac renin-angiotensin system and salt retention play the role in the development of cardiac hypertrophy and impaired diastolic function. QT interval prolongation, which is observed in 40-50 % of cirrhotic patients, occurs as a result of the derangement in membrane fluidity and ion channel defect. The increased recognition of this disease will prevent the complications of overt heart failure after procedures such as transjugular intrahepatic portosystemic shunt (TIPS) and liver transplantation. Better understandings of the pathogenesis and pathology of cirrhotic cardiomyopathy is crucial in developing more accurate diagnostic tools and specific treatments of this condition.

[Hepatocardiac disorders : Interactions between two organ systems]

Interactions between the hepatic portal and cardiovascular systems are frequently found in patients with liver disease. Cirrhotic cardiomyopathy (CCMP) is defined as reduced cardiac function in patients with liver cirrhosis in the absence of other known causes of cardiac disease. The typical hyperdynamic circulatory state by means of increased cardiac output and reduced systemic vascular resistance may mask left ventricular failure. Portopulmonary hypertension (POPH) is defined as increased pulmonary arterial pressure and the presence of portal hypertension, and is associated with increased mortality. Targeted medical therapies include vasodilators such as prostanoids, endothelin receptor antagonists and phosphodiesterase-5 inhibitors. Hypoxic or ischaemic hepatitis (HH) is defined by a sharp increase of serum aminotransferase levels due to liver cell necrosis as result of cardiac, circulatory or respiratory failure. An overview of these diseases is provided in this article.

Impact of cardiac dysfunction on health-related quality of life in cirrhotic liver transplant candidates

OBJECTIVE

Cardiac dysfunction, in particular left ventricular diastolic dysfunction, is common in cirrhosis. We aimed to investigate the impact of cardiac dysfunction on health-related quality of life (QoL) in liver cirrhosis.

MATERIALS AND METHODS

A total of 88 cirrhotic liver transplant candidates with an available echocardiogram and ECG completed the Short form-36 (SF-36) and Fatigue Impact Scale. In a subgroup of 61 patients, levels of cardiac biomarkers, in particular serum N-terminal pro-brain natriuretic peptide, adiponectin, and high-sensitive troponin T, were also measured.

RESULTS

Although left ventricular systolic diameter was related to a lower SF-36 physical component summary, neither left ventricular diastolic dysfunction nor any other echocardiographic feature was found to be associated with any other SF-36 or Fatigue Impact Scale domain (P>0.05 for all). On linear regression analysis after adjustment for confounders, a prolonged QTc interval was found to be related to a lower SF-36 mental component summary score (β=-9.7, P=0.009) and increased physical fatigue (β=10.5, P=0.004). Neither serum N-terminal pro-brain natriuretic peptide, high-sensitivity troponin T, nor adiponectin levels were found to be related to QoL (P>0.05 for all). Serum adiponectin levels did not differ among patients with versus those without echocardiographic cardiac alterations (P>0.05 for all).

CONCLUSION

A prolonged QTc interval, but not any echocardiographic abnormalities or cardiac biomarkers, seems to be predictive of QoL in cirrhosis.

Recent advances in the diagnosis and management of cirrhosis-associated cardiomyopathy in liver transplant candidates: advanced echo imaging, cardiac biomarkers, and advanced heart failure therapies

Patients with end-stage liver disease in need of liver transplantation increasingly are older with a greater burden of cardiac disease and other co-morbidities, which may increase perioperative risk and adversely affect long-term prognosis. Cirrhosis of any etiology manifests hemodynamically as a state of low systemic vascular resistance, with high peripheral, but low central blood volume, leading to a state of neurohormonal activation and high cardiac output, which may adversely affect cardiac reserve under extreme perioperative stress, aptly termed cirrhosis-associated or cirrhotic cardiomyopathy. Evidence of asymptomatic cirrhotic cardiomyopathy may be found in subtle electrocardiographic and echocardiographic changes, but may progress to severe heart failure under the demands of bleeding and transfusions, vasopressors, rebounding peripheral vascular resistance, withdrawal of cardioprotective beta-blockers and mineralocorticoid antagonists, exacerbated by sepsis or systemic inflammatory response syndrome. This review will add to the current body of literature on cirrhotic cardiomyopathy by focusing on the role of advanced echocardiographic imaging techniques, cardiac biomarkers, and advanced heart failure therapies available to manage patients with cirrhotic cardiomyopathy while waiting for liver transplant and during the perioperative period.

Appraising cardiac dysfunction in liver transplantation: an ongoing challenge

End-stage liver disease (ESLD) is a multisystemic disease that adversely and mutually aggravates other organs such as the heart. Cardiac dysfunction in ESLD encompasses a spectrum of disease that could be aggravated, precipitated or be occurring hand-in-hand with coexisting aetiological factors precipitating cirrhosis. Additionally and more complexly, liver transplantation, the curative modality of ESLD, is responsible for additional intra- and postoperative short- and long-term cardiac morbidity. The phenotypic distinction of the different forms of cardiac dysfunction in ESLD albeit important prognostically and therapeutically is not allowed by the current societal recommendations, due to conceptual, and methodological limitations in the appraisal of cardiac function and structure in ESLD and in designing studies that are based on this appraisal. This review comprehensively discusses the spectrum of cardiac dysfunction in ESLD, discusses the limitations of the current appraisal of cardiac dysfunction in ESLD, and proposes a hypothetical approach for studying cardiac dysfunction in liver transplant candidates.

QT interval prolongation in end-stage liver disease cannot be explained by nonhepatic factors

INTRODUCTION

QT interval prolongation in patients with end-stage liver disease (ESLD) is common. However, electrolyte abnormalities, renal insufficiency, treatment with QT-prolonging drugs, and other factors known to prolong QT interval independently of liver disease occur frequently in ESLD. Moreover, elevated heart rate may be present in ESLD and result in spurious QTc prolongation if the Bazett formula is used for rate correction. It thus remains unclear whether QT prolongation in ESLD is directly caused by liver failure, or indirectly by these confounding factors.

METHODS

Medical records of all patients (n = 437) who received orthotopic liver transplantation (OLTx) at our institution between 2008 and 2011 were reviewed. Data from 51 patients with available pre-OLTx dobutamine stress echo (DSE), post-OLTx ECG and without nonhepatic factors affecting QT interval duration were analyzed. For each patient, QT versus RR regression line was calculated from ECG tracings obtained during DSE. The QT interval on post-OLTx ECG was compared with the pre-OLTx QT predicted by the regression line for the same RR interval.

RESULTS

QT interval shortened significantly post-OLTx (from 394 ± 47 to 364 ± 45 ms at RR interval 750 ± 144 ms; P < 0.002) when compared using the regression method. Corrected QT intervals calculated by Bazett and Fridericia formulas also shortened. Patients with prolonged QT pre-OLTx had significantly higher INR and lower serum albumin.

CONCLUSION

ESLD impairs ventricular repolarization even in the absence of other known factors affecting repolarization. QT prolongation in ESLD is associated with impaired synthetic liver function.

Prevalence of pre-transplant electrocardiographic abnormalities and post-transplant cardiac events in patients with liver cirrhosis

Background

Although cardiovascular disease is thouht to be common in cirrhosis, there are no systematic investigations on the prevalence of electrocardiographic (ECG) abnormalities in these patients and data on the occurrence of post-transplant cardiac events in comparison with the general population are lacking. We aimed to study the prevalence and predictors of ECG abnormalities in patients with cirrhosis undergoing liver transplantation and to define the risk of cardiac events post-transplant compared to the general population.

Methods

Cirrhotic patients undergoing first-time liver transplantation between 1999–2007 were retrospectively enrolled. ECGs at pre-transplant evaluation were reviewed using the Minnesota classification and compared to healthy controls. Standardized incidence ratios for post-transplant cardiac events were calculated.

Results

234 patients with cirrhosis were included, 186 with an available ECG (36% with alcoholic and 24% with viral cirrhosis; mean follow-up 4 years). Cirrhotics had a prolonged QTc interval, a Q wave, abnormal QRS axis deviation, ST segment depression and a pathologic T wave more frequently compared to controls (p < 0.05 for all). Arterial hypertension, older age, cirrhosis severity and etiology were related to ECG abnormalities. Compared to the general Swedish population, patients were 14 times more likely to suffer a cardiac event post-transplant (p < 0.001). A prolonged QTc interval and Q wave were related to post-transplant cardiac events (p < 0.05 for all).

Conclusions

Pre-transplant ECG abnormalities are common in cirrhosis and are associated with cardiovascular risk factors and cirrhosis severity and etiology. Post-transplant cardiac events are more common than in the general population.

Effects of carvedilol and propranolol on circulatory regulation and oxygenation in cirrhosis: a randomised study

BACKGROUND AND AIMS

Newer studies suggest that carvedilol, a beta-blocker with a moderate anti-alpha-1 activity, is superior to propranolol in reducing the portal pressure and risk of variceal bleeding. The effect on arterial blood pressure is a matter of concern especially in decompensated patients.

AIMS

to assess potential differential effects of beta-blockers and beta-blockers with moderate anti-alpha-1 activity on selected haemodynamic, humoral, and respiratory characteristics in cirrhosis.

METHODS

Patients with cirrhosis and portal hypertension were randomised to receive carvedilol (n=16) or propranolol (n=13). Cardiac, systemic and splanchnic parameters along with oxygen saturation and plasma renin were measured at inclusion and after 3 months.

RESULTS

Arterial blood pressure, heart rate, and cardiac output decreased equally, central circulation time and systemic vascular resistance increased significantly but similarly. Central blood volume, plasma volume and arterial compliance were unaltered. The QTc interval and renin levels decreased in the carvedilol group, however not significantly different from the propranolol group. Arterial oxygen saturation and alveolar arterial oxygen gradient remained constant in both groups. Hepatic venous pressure gradient decreased equally in the carvedilol and propranolol groups (-17% and -20%, non significant).

CONCLUSIONS

Systemic haemodynamics and pulmonary effects of carvedilol and propranolol are modest and this study could not demonstrate any significant difference between the two treatments.

Cirrhotic cardiomyopathy: pathogenesis and clinical relevance

Cirrhosis is known to cause alterations in the systemic haemodynamic system. Cirrhotic cardiomyopathy designates a cardiac dysfunction that includes impaired cardiac contractility with systolic and diastolic dysfunction, as well as electromechanical abnormalities in the absence of other known causes of cardiac disease. This condition is primarily revealed by inducing physical or pharmacological stress, but echocardiography is excellent at revealing diastolic dysfunction and might also be used to detect systolic dysfunction at rest. Furthermore, measurement of circulating levels of cardiac biomarkers could improve the diagnostic assessm+ent. Cirrhotic cardiomyopathy contributes to various complications in cirrhosis, especially as an important factor in the development of hepatic nephropathy. Additionally, cirrhotic cardiomyopathy seems to be associated with the development of heart failure in relation to invasive procedures such as shunt insertion and liver transplantation. Current pharmacological treatment is nonspecific and directed towards left ventricular failure, and liver transplantation is currently the only proven treatment with specific effect on cirrhotic cardiomyopathy.

Interactions of the heart and the liver

There is a mutual interaction between the function of the heart and the liver and a broad spectrum of acute and chronic entities that affect both the heart and the liver. These can be classified into heart diseases affecting the liver, liver diseases affecting the heart, and conditions affecting the heart and the liver at the same time. In chronic and acute cardiac hepatopathy, owing to cardiac failure, a combination of reduced arterial perfusion and passive congestion leads to cardiac cirrhosis and cardiogenic hypoxic hepatitis. These conditions may impair the liver function and treatment should be directed towards the primary heart disease and seek to secure perfusion of vital organs. In patients with advanced cirrhosis, physical and/or pharmacological stress may reveal a reduced cardiac performance with systolic and diastolic dysfunction and electrophysical abnormalities termed cirrhotic cardiomyopathy. Electrophysiological abnormalities include prolonged QT interval, chronotropic incompetance, and electromechanical uncoupling. No specific therapy can be recommended, but it should be supportive and directed against the heart failure. Numerous conditions affect both the heart and the liver such as infections, inflammatory and systemic diseases, and chronic alcoholism. The risk and prevalence of coronary artery disease are increasing in cirrhotic patients and since the perioperative mortality is high, a careful cardiac evaluation of such patients is required prior to orthotopic liver transplantation.

Clinical predictors of post-liver transplant new-onset heart failure

Objectives of this study were (1) to evaluate preoperative predictors of systolic and diastolic heart failure in patients undergoing liver transplantation (LT) and (2) to describe the prognostic implications of systolic and diastolic heart failure in these patients. The onset of heart failure after orthotopic LT remains poorly understood. Data were obtained for all LT recipients between January 2000 and December 2010. The primary outcome was post-LT heart failure: systolic (ejection fraction ≤ 50%), diastolic, or mixed heart failure. Patients underwent echocardiographic evaluation before and after LT. Pretransplant variables were evaluated as predictors of heart failure with Cox proportional hazards model. 970 LT recipients were followed for 5.3 ± 3.4 years. Ninety-eight patients (10.1%) developed heart failure in the posttransplant period. There were 67 systolic (6.9%), 24 diastolic (2.5%), and 7 mixed systolic/diastolic (0.7%) heart failures. Etiology was ischemic in 18 (18.4%), tachycardia-induced in 8 (8.2%), valvular in 7 (7.1%), alcohol-related in 4 (4.1%), hypertensive heart disease in 3 (3.1%), and nonischemic in majority of patients (59.2%). Pretransplant grade 3 diastolic dysfunction, diabetes, hypertension, mean arterial pressure ≤ 65 mm Hg, mean pulmonary artery pressure ≥ 30 mm Hg, mean pulmonary capillary wedge pressure ≥ 15 mm Hg, hemodialysis, brain natriuretic peptide level and QT interval > 450 ms were found to be predictive for the development of new-onset systolic heart failure. However beta-blocker use before LT and tacrolimus after LT were associated with reduced development of new-onset systolic heart failure. In conclusion, pretransplant risk factors, hemodynamic variables, and echocardiographic variables are important predictors of post-LT heart failure. In patients undergoing LT, postoperative onset of systolic or diastolic heart failure was found to be an independent predictor of mortality.

Cardiac and renal effects of a transjugular intrahepatic portosystemic shunt in cirrhosis

Refractory ascites and recurrent variceal bleeding are among the serious complications of portal hypertension and cirrhosis for which a transjugular intrahepatic portosystemic shunt (TIPS) can be used. Cirrhotic patients have varying degrees of haemodynamic derangement, mainly characterized by peripheral arterial vasodilatation, central underfilling and activation of several vasoactive systems. These changes affect the heart, the lungs and the kidneys in particular. The cardiac effects of TIPS are immediate and are related to the redirection of blood from the splanchnic circulation into the systemic circulation, resulting in worsening of the hyperdynamic circulation with increasing cardiac output and decreasing systemic vascular resistance; further, TIPS may unmask a latent diastolic dysfunction of the heart. However, the renal effects of TIPS seem to be beneficial as renal function tends to improve in patients with the hepatorenal syndrome. The clinical and haemodynamic effects of TIPS have been studied intensively and will be reviewed in the present paper. Considerable knowledge on the effects of TIPS on the pathophysiology of cirrhosis has been gained, but studies on the central haemodynamic effects are warranted to refine the already applied treatments and develop new treatment modalities.

Diastolic dysfunction in patients with end-stage liver disease is associated with development of heart failure early after liver transplantation

BACKGROUND

Liver transplantation (LTx) is a life-saving treatment of end-stage liver disease. Cardiac complications including heart failure (HF) are among the leading causes of death after LTx.

THE AIM

The aim is to identify clinical and echocardiographic predictors of developing HF after LTx.

METHODS

Patients who underwent LTx at the University of Nebraska Medical Center (UNMC) between January 2001 and January 2009 and had echocardiographic study before and within 6 months after transplantation were identified. Patients with coronary artery disease (>70% lesion) were excluded. HF after LTx was defined by clinical signs, symptoms, radiographic evidence of pulmonary congestion, and echocardiographic evidence of left ventricular dysfunction (left ventricle ejection fraction <50%).

RESULTS

Among 107 patients (presented as mean age [SD], 55 [10] years; male, 70%) who met the inclusion criteria, 26 (24%) patients developed HF after LTx. The pre-LTx left ventricle ejection fraction did not differ between the HF (69 [7]) and the control groups (69 [7] vs. 67 [6], P=0.30). However, pre-LTx elevation of early mitral inflow velocity/mitral annular velocity (P=0.02), increased left atrial volume index (P=0.05), and lower mean arterial pressure (P=0.03) were predictors of HF after LTx in multivariate analysis. Early mitral inflow velocity/mitral annular velocity greater than 10 and left atrial volume index 40 mL/m2 or more were associated with a 3.4-fold (confidence interval, 1.2-9.4; P=0.017) and 2.9-fold (confidence interval, 1.1-7.5; P=0.03) increase in risk of development of HF after LTx, respectively.

CONCLUSIONS

This study suggests that elevated markers of diastolic dysfunction during pre-LTx echocardiographic evaluation are associated with an excess risk of HF and may predict post-LTx survival.

QT interval prolongation by acute gastrointestinal bleeding in patients with cirrhosis

BACKGROUND & AIMS

QT interval prolongation is frequent in cirrhosis, and stressful conditions could further prolong QT. We aimed to test this hypothesis and, if it proved correct, to assess its prognostic meaning.

METHODS

We reviewed the clinical records of 70 consecutive cirrhotic and 40 non-cirrhotic patients with acute gastrointestinal bleeding. All patients had been evaluated before bleeding (T0) and were re-evaluated at the time of bleeding (T1) and 6 weeks afterwards (T2).

RESULTS

QT corrected by heart rate (QTc) lengthened at T1, returning towards baseline values at T2 (mean ± SEM; from 415.9 ± 4.3 to 453.4 ± 4.3 to 422.2 ± 5.7 ms, P < 0.001) in cirrhotics; contrariwise, QTc did not change in non-cirrhotic patients. The 6-week mortality was 29.6% among cirrhotic patients, while no control patient died. At T1, patients who died had longer QTc (P = 0.001) and higher model of end-stage liver disease (MELD) score (P < 0.001) than survivors. MELD and QTc independently predicted survival. Their areas under the ROC curve were 0.88 (CI 95% 0.78-0.95) and 0.75 (CI 95% 0.63-0.85) respectively; the best cut-off values were MELD ≥20 and QTc ≥ 460 ms. Based on these factors, the 6-week mortality was: 0% for patients without risk factors, 32.1% for those with one risk factor and 70.6% for those with both (P < 0.001).

CONCLUSIONS

Acute gastrointestinal bleeding further prolongs QTc in cirrhosis. This abnormality independently predicts bleeding-induced mortality. The combined measurement of QTc interval and MELD can clearly identify three patient strata at increasing risk of bleeding-related mortality, thus improving the decision-making for these patients.

QT interval prolongation in liver cirrhosis: innocent bystander or serious threat?

The ECG QT interval measures the length of ventricular systole. Its prolongation is essentially caused by a delayed repolarization phase, and is associated with an increased risk of ventricular arrhythmias and sudden death in several congenital and acquired conditions. Abnormalities in cardiac electrophysiology are well documented in patients with liver cirrhosis, and the prolonged QT interval has emerged as the electrophysiological hallmark of cirrhotic cardiomyopathy. This article will focus on: first, the epidemiology of QT interval prolongation in cirrhosis; second, the potential molecular mechanisms responsible for the pathogenesis of this electrophysiological abnormality and the putative role of circulating cardiotoxins; third, its prognostic meaning; and fourth, its clinical relevance, in terms of the association between the presence of a long QT interval and the occurrence of ventricular arrhythmias in cirrhotic patients treated with drugs known to increase the QT length or exposed to stressful conditions, such as liver transplantation, gastrointestinal bleeding and shock.

Effect of propranolol on the relationship between QT interval and vagal modulation of heart rate variability in cirrhotic patients awaiting liver transplantation

BACKGROUND

Prolonged corrected QT (QT(c)) interval and vagal dysfunction are common occurrences in liver cirrhosis and are determinants of mortality in patients with chronic liver disease. We evaluated whether propranolol can affect the relationship between QT(c) interval and cardiac vagal control of heart rate variability (HRV) in cirrhotic patients awaiting liver transplantation.

METHODS

We compared 50 cirrhotic patients (M/F = 43/7, 52.6 ± 8.4 years, Child-Pugh class A/B/C: 9/24/17) receiving propranolol with a sex-, age-, and liver disease severity-matched control group of 50 patients (M/F = 43/7, 52.0 ± 8.3 year, Child-Pugh class A/B/C: 9/24/17) not receiving propranolol. Among the parameters evaluated were QT(c) interval and cardiac vagal indices of HRV, including the root mean square of successive differences in R-R intervals (RMSSD); spectral power in the high-frequency range (HF); standard deviation (SD)1 in Poincare plot; and sample entropy. Correlations between QT(c) interval and vagal indices of HRV were analyzed.

RESULTS

The mean duration of preoperative propranolol treatment in the propranolol group was 19.4 ± 24.7 months. QT(c) interval was significantly lower, whereas RMSSD, HF, SD1, and sample entropy were significantly higher in the propranolol group than in the control group. Correlation coefficients between QT(c) interval and RMSSD, HF, SD1, and sample entropy were higher in the propranolol group than in the control group.

CONCLUSIONS

The prolonged QT(c) interval observed in cirrhotic patients may be reduced by propranolol administration, an effect attributable to improved vagal cardiac modulation. These findings suggest that propranolol may have a beneficial effect on perioperative mortality in cirrhotic patients awaiting liver transplantation.

The heart in liver transplantation

The heart and liver are organs that are closely related in both health and disease. Patients who undergo liver transplantation may suffer from heart disease that is: (a) related to the original cause of the liver disease such as hemochromatosis, (b) related to the liver disease itself, or (c) related to other associated conditions. Furthermore, liver transplantation is one of the most cardiovascular stressful events that a patient with cirrhosis may undergo. After liver transplantation, the progression of pre-existing or the development of new-onset cardiac disease may occur. This article reviews the relationship between the heart and liver transplantation in the pre-transplant, intra-operative, and post-transplant periods.

Perspectives on fibrosis progression in hepatitis C: an à la carte approach to risk factors and staging of fibrosis

The morbidity and mortality of chronic hepatitis C is related to progressive fibrosis and the development of cirrhosis. The development of fibrosis in patients with HCV is highly influenced by immune status, host response to the virus and associated factors, such as, age, sex, alcohol intake, diabetes, obesity and coinfection with other viruses. The rate of fibrosis progression differs depending on several factors, including the stage of fibrosis and the time since infection. Routine assessment of fibrosis through biopsy every 3-5 years has poor patient acceptance and reliability, and might result in missed opportunities to improve or modify treatment priorities. Enhanced understanding of the pathophysiology of liver fibrosis in HCV infection has led to the development of a number of non-invasive assessment modalities. The ideal test would discriminate fibrosis in the categories none/early (stages 0/1), intermediate (stage 2) and advanced fibrosis/cirrhosis (stages 3/4) and be readily available, inexpensive and accurate. Biomarker tests utilize individual or combined serum markers to determine the degree of fibrosis. Other strategies combine biomarkers with clinical variables, such as patient age or utilize liver imaging or functional assessments. Incorporation of appropriately validated non-invasive assessments of liver fibrosis will likely improve the clinical care of patients with HCV infection.

Reduced baroreflex sensitivity and pulmonary dysfunction in alcoholic cirrhosis: effect of hyperoxia

Patients with cirrhosis exhibit impaired regulation of the arterial blood pressure, reduced baroreflex sensitivity (BRS), and prolonged QT interval. In addition, a considerable number of patients have a pulmonary dysfunction with hypoxemia, impaired lung diffusing capacity (Dl(CO)), and presence of hepatopulmonary syndrome (HPS). BRS is reduced at exposure to chronic hypoxia such as during sojourn in high altitudes. In this study, we assessed the relation of BRS to pulmonary dysfunction and cardiovascular characteristics and the effects of hyperoxia. Forty-three patients with cirrhosis and 12 healthy matched controls underwent hemodynamic and pulmonary investigations. BRS was assessed by cross-spectral analysis of variabilities between blood pressure and heart rate time series. A 100% oxygen test was performed with the assessment of arterial oxygen tensions (Pa(O(2))) and alveolar-arterial oxygen gradient. Baseline BRS was significantly reduced in the cirrhotic patients compared with the controls (4.7 +/- 0.8 vs. 10.3 +/- 2.0 ms/mmHg; P < 0.001). The frequency-corrected QT interval was significantly prolonged in the cirrhotic patients (P < 0.05). There was no significant difference in BRS according to presence of HPS, Pa(O(2)), Dl(CO), or Child-Turcotte score, but BRS correlated with metabolic and hemodynamic characteristics. After 100% oxygen inhalation, BRS and the QT interval remained unchanged in the cirrhotic patients. In conclusion, BRS is significantly reduced in patients with cirrhosis compared with controls, but it is unrelated to the degree of pulmonary dysfunction and portal hypertension. Acute hyperoxia does not significantly revert the low BRS or the prolonged QT interval in cirrhosis.

Cirrhotic cardiomyopathy

Increased cardiac output was first described in patients with cirrhosis more than fifty years ago. Later, various observations have indicated the presence of a latent cardiac dysfunction, which includes a combination of reduced cardiac contractility with systolic and diastolic dysfunction and electrophysiological abnormalities. This syndrome is termed cirrhotic cardiomyopathy. Results of experimental studies indicate the involvement of several mechanisms in the pathophysiology, such as reduced beta-adrenergic receptor signal transduction, altered transmembrane currents and electromechanical coupling, nitric oxide overproduction, and cannabinoid receptor activation. Systolic incompetence in patients can be revealed by pharmacological or physical strain and during stressful procedures, such as transjugular intrahepatic portosystemic shunt insertion and liver transplantation. Systolic dysfunction has recently been implicated in development of renal failure in advanced disease. Diastolic dysfunction reflects delayed left ventricular filling and is partly attributed to ventricular hypertrophy, subendocardial oedema, and altered collagen structure. The QT interval is prolonged in about half of the cirrhotic patients and it may be normalised by beta-blockers. No specific therapy for cirrhotic cardiomyopathy can be recommended, but treatment should be supportive and directed against the cardiac dysfunction. Future research should better describe the prevalence, impact on morbidity and survival, and look for potential treatments.

Prolongation of QT interval induced by electroconvulsive therapy is attenuated by landiolol

OBJECTIVE

The objective of this study was to determine if landiolol, ultra short-acting beta adrenoceptor antagonist, attenuates the prolongation of QT interval caused by electroconvulsive therapy (ECT).

METHODS

Fifteen patients, scheduled to undergo ECT for the treatment of major depression disorder, were studied. In each patient, 2 sessions of ECT were picked up and randomly assigned to be administered with (treatment L) or without continuous infusion of landiolol (treatment C). Electroconvulsive therapy was administered under general anesthesia with propofol and suxamethonium. Raw electrocardiogram waves were obtained from anesthesia monitor and stored on a personal computer. Automated electrocardiogram analyzing software was used for the determination of QT interval.

RESULTS

The increase in corrected QT caused by suxamethonium was significantly smaller in treatment L (36.8 +/- 14.5 ms for treatment C vs 17.9 +/- 6.5 ms for treatment L; P < 0.001). The increase in corrected QT caused by ECT was also smaller in treatment L (72.3 +/- 23.1 ms for treatment C vs 54.6 +/- 17.9 ms for treatment L; P = 0.02).

CONCLUSIONS

The prolongation of QT interval caused by SUX and ECT was partially attenuated by landiolol.

Pegylated IFN-alpha2a and ribavirin in the treatment of hepatitis C

Chronic hepatitis C is a major worldwide health problem with an estimated prevalence of 1.6-2%. The prognosis of chronic hepatitis C depends on the rate of fibrosis progression which, over a 20-30-year time span, may determine the risk of developing cirrhosis and its complications, namely hepatocellular carcinoma, liver decompensation, hepatic encefalopathy and espohageal variceal bleeding. The only therapeutic measure able to halt this progressive process is HCV eradication by interferon (IFN)-based therapies. HCV clearance benefits patients with chronic hepatitis C, by preventing the progression to cirrhosis, as well as those with established cirrhosis, by effectively reducing the risk of liver-related complications. The latest innovation in anti-HCV treatment has been the pegylation of the IFN molecule through the attachment of one or more polyethylene glycols to the IFN molecule, drastically modifying the immunological, pharmacokinetic and pharmacodynamic properties of the drug. Following the demonstration of a more potent antiviral effect in terms of sustained virological response rates in Phase III randomized trials, pegylated IFN coupled with ribavirin has become the standard of care for chronic hepatitis C. Currently, two forms of pegylated IFN exist (alpha2a and alpha2b), which differ significantly in terms of pharmacokinetics and dynamics, is whether these peculiarities translate into different efficacy rates being still being debated.

Cardiac and systemic haemodynamic complications of liver cirrhosis

Cardiovascular complications of liver cirrhosis include cardiac dysfunction and abnormalities in the central-, splanchnic,- and peripheral circulation. Vasodilatation prevails, but vascular beds with various degrees of reduced and increased haemodynamic resistance are the results of massive activation of powerful homeostatic, regulatory systems. Cirrhotic cardiomyopathy implies systolic and diastolic dysfunction and electrophysiological abnormalities, an entity that is different from alcoholic heart muscle disease. Being often clinical latent, cirrhotic cardiomyopathy can be unmasked by physical and pharmacological strain. Cardiac failure is an important cause of mortality after liver transplantation and stressful procedures as insertions of transjugular intrahepatic portal systemic shunt (TIPS), peritoneal venous shunting, and other types of surgery. Improvement of liver function has been shown to reverse the cardiovascular complications. The clinical significance is an important topic for future research. At present, no specific treatment can be recommended, and the cardiac failure in cirrhosis should be treated as in non-cirrhotic patients with sodium restriction, diuretics, and beta-adrenergic blocking agents. Special care should be taken with the use of ACE-inhibitors and angiotensin antagonist in these patients.

"Torsade de pointes" during amiodarone infusion in a cirrhotic woman with a prolonged QT interval

We describe an interesting case of a woman with decompensated cirrhosis, ischaemic heart disease and prolonged QT interval, who developed a new-onset atrial fibrillation. During amiodarone infusion a torsade de pointes occurred, which was immediately converted to sinus rhythm by synchronized cardioversion. A new episode of atrial fibrillation was treated with infusion of a beta-blocker (metoprolol) that restored sinus rhythm and normalized the QT interval. Delayed repolarization, frequently observed in ischaemic heart disease, cirrhosis and pro-arrhythmic drugs administration, represents the background for the development of torsade de pointes. Our report underlines that the potential harmfulness of a prolonged QT interval in cirrhotic patients is currently not perceived in its entirety, so that various categories of drugs affecting ventricular repolarization are rather thoughtlessly used in clinical practice without monitoring the QT interval. Thus, amiodarone should be avoided, if possible, or used with extreme care in arrhythmic patients with advanced liver disease. Moreover, beta-blockers may be considered the first-line treatment for rate-control during supraventricular tachyarrhythmias in cirrhotic patients with delayed repolarization.

QT interval prolongation and decreased heart rate variability in cirrhotic patients: relevance of hepatic venous pressure gradient and serum calcium

A prolongation of QT interval has been shown in patients with cirrhosis and it is considered as part of the definition of the so-called 'cirrhotic cardiomyopathy'. The aim of the present study was to assess the determinants of QT interval prolongation in cirrhotic patients. Forty-eight male patients with different stages of liver disease were divided into three subgroups according to the Child-Pugh classification. All patients underwent a 24-h ECG Holter recording. The 24-h mean of QT intervals corrected for heart rate (termed QTc) and the slope of the regression line QT/RR were calculated. HRV (heart rate variability), plasma calcium and potassium concentration and HVPG (hepatic venous pressure gradient) were measured. QTc was progressively prolonged from Child A to Child C patients (P=0.001). A significant correlation between QTc and HVPG was found (P=0.003). Patients with alcohol-related cirrhosis presented QTc prolongation more frequently than patients with post-viral cirrhosis (P<0.001). The QT/RR slope was steeper in subjects with alcoholic aetiology as compared with viral aetiology (P=0.02), suggesting that these patients have a further QTc prolongation when heart rate decreases. The plasma calcium concentration was inversely correlated with QTc (P<0.001). The presence of severe portal hypertension was associated with decreased HRV (P<0.001). Cirrhotic patients with a more severe disease, especially of alcoholic aetiology, who have greater HVPG and lower calcium plasma levels, have an altered ventricular repolarization and a reduced vagal activity to the heart, which may predispose to life-threatening arrhythmias.

Impact of liver transplantation on rate-corrected QT interval and myocardial function in children with chronic liver disease*

Prolonged QTc interval (>440 ms) is a common abnormality in adult patients with CLD and has been reported to predict patient survival. In this study, 88 children who underwent evaluation for LT, including a 12-lead electrocardiogram and echocardiogram included to determine the frequency of QTc prolongation and related factors in children with CLD and the effect of LT on these factors. Sixty-nine healthy, age- and sex-matched children served as controls. QTc interval was prolonged in 40 CLD patients (45.4%). It was found to be related to PELD score and presence of portal hypertension. Mean QTc was higher in patients who died prior to LT than in the survivors without LT. Mortality risk was increased 3.66-fold in patients with prolonged QTc (p = 0.001, 95% CI: 2-7.2). Cox regression analysis showed that only PELD score was an independent predictor of survival (p = 0.001, beta = -0.41, 95% CI: 5.58-1.82). Five of 48 transplanted children died within three months post-transplant; QTc was not related to post-transplant survival (p = 0.27). QTc normalized in 63.8% patients after LT. After LT, LAD, LVEF, and LVPWT decreased. In conclusion, QTc prolongation is common in children with CLD and associated with high mortality. It may be useful for assessment of the severity of CLD and for the timing for transplantation.

The heart and the liver

Cardiac failure affects the liver and liver dysfunction affects the heart. Chronic and acute heart failure can lead to cardiac cirrhosis and cardiogenic ischemic hepatitis. These conditions may impair liver function and treatment should be directed towards the primary heart disease and seek to secure perfusion of vital organs. In patients with advanced cirrhosis, physical and/or pharmacological stress may reveal a reduced cardiac performance with systolic and diastolic dysfunction and electrophysical abnormalities, termed cirrhotic cardiomyopathy. Pathophysiological mechanisms include reduced beta-adrenergic receptor signal transduction and defective cardiac electromechanical coupling. However, the QT interval is prolonged in approximately half of patients with cirrhosis and it may be improved by beta-blockers. No specific therapy can be recommended but it should be supportive and directed against the heart failure. Transjugular intrahepatic portosystemic shunt insertion and liver transplantation affect cardiac function in portal hypertensive patients and cause stress to the cirrhotic heart, with a risk of perioperative heart failure. The risk and prevalence of coronary artery disease are increasing in cirrhotic patients and since perioperative mortality is high, careful evaluation of such patients with dobutamine stress echocardiography, coronary angiography and myocardial perfusion imaging is required prior to liver transplantation. Future research should focus on beneficial effects of treatment on cardiac function and mortality.