Prolonged Q-T(c) interval in mild portal hypertensive cirrhosis

How non-alcoholic fatty liver disease and cirrhosis affect the heart

Liver diseases affect the heart and the vascular system. Cardiovascular complications appear to be a leading cause of death in patients with non-alcoholic fatty liver disease (NAFLD) and cirrhosis. The predominant histological changes in the liver range from steatosis to fibrosis to cirrhosis, which can each affect the cardiovascular system differently. Patients with cirrhotic cardiomyopathy (CCM) and NAFLD are at increased risk of impaired systolic and diastolic dysfunction and for suffering major cardiovascular events. However, the pathophysiological mechanisms behind these risks differ depending on the nature of the liver disease. Accurate assessment of symptoms by contemporary diagnostic modalities is essential for identifying patients at risk, for evaluating candidates for treatment, and prior to any invasive procedures. This review explores current perspectives within this field.

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.

Prolonged QT Interval in Cirrhosis: Twisting Time?

Approximately 30% to 70% of patients with cirrhosis have QT interval prolongation. In patients without cirrhosis, QT prolongation is associated with an increased risk of ventricular arrhythmias, such as torsade de pointes (TdP). In cirrhotic patients, there is likely a significant association between the corrected QT (QTc) interval and the severity of liver disease, and possibly with increased mortality. We present a stepwise overview of the pathophysiology and management of acquired long QT syndrome in cirrhosis. The QT interval is mainly determined by ventricular repolarization. To compare the QT interval in time it should be corrected for heart rate (QTc), preferably by the Fridericia method. A QTc interval >450 ms in males and >470 ms in females is considered prolonged. The pathophysiological mechanism remains incompletely understood, but may include metabolic, autonomic or hormonal imbalances, cirrhotic heart failure and/or genetic predisposition. Additional external risk factors for QTc prolongation include medication (IKr blockade and altered cytochrome P450 activity), bradycardia, electrolyte abnormalities, underlying cardiomyopathy and acute illness. In patients with cirrhosis, multiple hits and cardiac-hepatic interactions are often required to sufficiently erode the repolarization reserve before long QT syndrome and TdP can occur. While some risk factors are unavoidable, overall risk can be mitigated by electrocardiogram monitoring and avoiding drug interactions and electrolyte and acidbase disturbances. In cirrhotic patients with prolonged QTc interval, a joint effort by cardiologists and hepatologists may be useful and significantly improve the clinical course and outcome.

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.

Prolonged QTc interval predicts long-term mortality in cirrhosis: a propensity score matching analysis

BACKGROUND

Prolonged corrected QT (QTc) interval is a hallmark of cirrhotic cardiomyopathy (CCM) and has been ascertained to predict mortality in cirrhosis. However, some critical issues remain to be addressed including unanimous cut-off, calculation approach and applicable population.

METHODS

A total of 274 patients with cirrhosis were included. The prolonged QTc interval over 440 ms according to adjusted Fridericia's formula was used to stratify enrolled subjects. Independent predictors of 3-year mortality were identified with Cox regression model. The Kaplan-Meier method was implemented to obtain survival curves. To reduce impact of selection bias and possible confounders, a propensity score matching (PSM) analysis was used.

RESULTS

QTc > 440 ms was an independent risk factor in the entire cohort and PSM subset (HR 2.532, 95% CI 1.431-4.480, p=.001; HR 2.802, 95% CI 1.171-6.701, p=.021, respectively). Subgroup analysis showed that QTc > 440 ms was an independent predictor in cirrhotics with age ≤60 years (HR = 1.02, p=.035) and in the presence of ascites (HR = 1.01, p=.008).

CONCLUSIONS

The prolonged QTc interval might help to identify patients with high-risk of all-cause mortality.

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.

QTc interval prolongation in liver cirrhosis with upper gastrointestinal bleeding

QTc interval prolongation is common in patients with liver cirrhosis. Cirrhotic patients suffering from complications could also prolong QT interval. We aimed to explore the role of QTc interval prolongation in cirrhotic patients with upper gastrointestinal bleeding (UGIB). Overall, 167 patients were analyzed. QTc interval prolongation presented in 111 patients (66.5%). One hundred and seven patients (64.1%) suffered from acute UGIB. Results showed that RBC, Hb, ALB and calcium (Ca) were significantly lower, and DBIL, GGT, APTT, Child-Pugh score, MELD score and ALBI score were significantly higher in the prolongation group than those without QTc prolongation. AUROC of QTc was .699 (95%CI: .623-.768). In the acute UGIB subgroup, AUROC of QTc was .478 (95%CI: .347-.611). In the HBV subgroup, AUROC of QTc was .722 (95%CI: .616-.812). QTc interval prolongation was prevalent in cirrhotic patients with UGIB and correlated with liver dysfunction. QTc might not be a valid predictor of in-hospital mortality.

Electrocardiographic Changes in Liver Cirrhosis-Clues for Cirrhotic Cardiomyopathy

Background and Objectives: Cirrhotic cardiomyopathy is a chronic cardiac dysfunction associated with liver cirrhosis, in patients without previous heart disease, irrespective of the etiology of cirrhosis. Electrocardiography (ECG) is an important way to evaluate patients with cirrhosis and may reveal significant changes associated with liver disease. Our study aimed to evaluate ECG changes in patients with diagnosed liver cirrhosis and compare them to patients with chronic hepatitis. Materials and Methods: We evaluated laboratory findings and ECG tracings in 63 patients with cirrhosis and 54 patients with chronic hepatitis of viral etiology. The end points of the study were prolonged QT interval, QRS hypovoltage and T-peak-to-T-end decrease. We confirmed the diagnosis of cirrhotic cardiomyopathy using echocardiography data. Results: Advanced liver disease was associated with prolonged QT intervals. Also, QRS amplitude was lower in patients with decompensated cirrhosis than in patients with compensated liver disease. We found an accentuated deceleration of the T wave in patients with cirrhosis. These findings correlated to serum levels of albumin, cholesterol and ammonia. Conclusions: ECG changes in liver cirrhosis are frequently encountered and are important noninvasive markers for the presence of cirrhotic cardiomyopathy.

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.

Cirrhotic cardiomyopathy: the liver affects the heart

Cirrhotic cardiomyopathy historically has been confused as alcoholic cardiomyopathy. The key points for diagnosis of cirrhotic cardiomyopathy have been well explained, however this entity was neglected for a long time. Nowadays the diagnosis of this entity has become important because it is a factor that contributes significantly to morbidity-mortality in cirrhotic patients. Characteristics of cirrhotic cardiomyopathy are a hyperdynamic circulatory state, altered diastolic relaxation, impaired contractility, and electrophysiological abnormalities, particularity QT interval prolongation. The pathogenesis includes impaired function of beta-receptors, altered transmembrane currents and overproduction of cardiodepressant factors, such as nitric oxide, cytokines and endogenous cannabinoids. In addition to physical signs of hyperdynamic state and heart failure under stress conditions, the diagnosis can be done with dosage of serum markers, electrocardiography, echocardiography and magnetic resonance. The treatment is mainly supportive, but orthotopic liver transplantation appears to improve this condition although the prognosis of liver transplantation in patients with cirrhotic cardiomyopathy is uncertain.

Liver Fibrosis Is Associated With Corrected QT Prolongation During Ledipasvir/Sofosbuvir Treatment for Patients With Chronic Hepatitis C

Combination treatment of ledipasvir and sofosbuvir (LDV/SOF) is first-line treatment for patients with chronic hepatitis C genotype 1 in the United States, Europe, and Japan. However, the influence of LDV/SOF on the cardiovascular system is poorly characterized. A total of 470 chronic hepatitis C patients who started LDV/SOF treatment between September 2015 and February 2016 at nine hospitals in Japan were prospectively enrolled in this study. Corrected QT (QTc) prolongation was defined as a QTc interval ≥450 milliseconds. The sustained virologic response rate was 96.0% (451/470), and the discontinuance rate due to adverse effects was 0.9% (4/470). Among 395 patients whose electrocardiogram was evaluated over time and compared with baseline, the QTc interval was significantly prolonged during treatment and returned to baseline levels 12 weeks after the end of treatment. Twenty-four of 376 patients with baseline QTc intervals <450 milliseconds experienced on-treatment QTc prolongation. Higher aspartate aminotransferase-to-platelet ratio index scores (≥0.76; odds ratio, 4.375; P = 0.005) and longer QTc intervals (≥416 milliseconds; odds ratio, 4.823; P = 0.003) at baseline were significantly associated with on-treatment QTc prolongation on multivariate analysis. Patients with cirrhosis showed significantly longer QTc intervals than those without cirrhosis during treatment but not at baseline, and they developed on-treatment QTc prolongation at a higher rate than patients without cirrhosis. No cardiovascular events occurred, except for 1 patient who developed paroxysmal supraventricular tachycardia. Conclusion: Newly developed QTc prolongation was observed in 6.4% of Japanese patients during treatment and was associated with more advanced fibrosis. (Hepatology Communications 2018; 00:000-000).

The Impact of Cirrhosis and Prescription Medications on QTc Interval Before and After Liver Transplantation

BACKGROUND:

Higher rates of corrected QT (QTc) prolongation have been reported in patients with cirrhosis. The impact of liver transplantation and prescription medications on the natural history of QTc prolongation has yet to be well characterized.

METHODS:

This was a single-center review of patients receiving (group 1) or listed for (group 2) a liver transplant during 2014. Patients in group 1 were followed prospectively from the date of transplantation to assess rates of QTc normalization posttransplant. In group 2, patients were evaluated from the date of listing up until December 2015 to assess the prevalence of QTc prolongation among liver transplant candidates.

RESULTS:

In group 1, 22 (75.9%) patients with QTc intervals >460 milliseconds at the time of transplant established normal baseline QTc intervals following transplantation. The median time to this QTc normalization was 17 days. In group 2, 30 (16.9%) patients had at least 1 documented QTc interval >500 milliseconds with prevalence rates of 42.9%, 19.0%, and 10.2% in patients with natural model of end-stage liver disease scores of >30, 16 to 30, and <16, respectively ( P < .01). Overall, 49.4% of patients in group 1 and 47.5% of patients in group 2 were prescribed QTc prolonging medications.

CONCLUSION:

QTc prolongation will resolve following transplantation in the majority of patients and generally occurs within the first several weeks. Among the listed liver transplant candidates, higher rates of clinically significant QTc prolongation may be observed in patients with more severe underlying cirrhosis. QTc prolonging medications are commonly prescribed in this population and warrant monitoring following initiation.

Cirrhotic cardiomyopathy: Implications for liver transplantation

The majority of patients on a waiting list for liver transplantation have end-stage liver disease. Because of the marked peripheral vasodilatation of end-stage cirrhosis that masks a latent myocardial dysfunction, cardiac abnormalities in the resting state are usually subclinical and escape the attention of physicians. However, when challenged, the systolic and diastolic contractile responses are attenuated. In addition to these contractile abnormalities, morphological changes, such as enlargement or hypertrophy of cardiac chambers, and electrophysiological repolarization changes, including a prolonged QT interval, can be observed. The constellation of these cardiac abnormalities is termed cirrhotic cardiomyopathy. Liver transplantation induces significant cardiovascular stress. Clamping of the inferior vena cava and portal vein, hemorrhage and blood/volume infusion, and ischemia/reperfusion all cause hemodynamic fluctuation. The changing cardiac preload and afterload status increases the cardiac workload, and thus, the previously subclinical ventricular dysfunction may manifest as overt heart failure during the operative and perioperative periods. Cardiac dysfunction contributes to morbidity and mortality associated with liver transplantation. Cardiovascular events are the third leading cause of death in liver recipients. However, because liver transplantation is the only definitive treatment for end-stage liver failure and also appears to reverse cardiac abnormalities, it is important to understand the challenges of the heart in liver transplantation. This review focuses on cardiac status before, during, and after liver transplantation. Liver Transplantation 23 826-835 2017 AASLD.

Prevalence, Risk Factors and In-hospital Outcomes of QTc Interval Prolongation in Liver Cirrhosis

BACKGROUND

QTc interval prolongation is an electrocardiographic abnormality in liver cirrhosis. The objective of this study was to evaluate the prevalence, risk factors and in-hospital outcomes of QTc interval prolongation in Chinese patients with liver cirrhosis.

METHODS

This was a retrospective analysis of a total of 1,268 patients with liver cirrhosis who were consecutively admitted to our hospital between January 2011 and June 2014. QTc interval data were collected from the medical records. QTc interval prolongation was defined as QTc interval > 440 milliseconds.

RESULTS

The prevalence of QTc interval prolongation was 38.2% (485 of 1268). In the entire cohort, the risk factors for QTc interval prolongation included an older age, a higher proportion of alcohol abuse and ascites, higher bilirubin, blood urea nitrogen, creatinine, prothrombin time, international normalized ratio, Child-Pugh score and model for end-stage liver diseases score, and lower red blood cell (RBC), hemoglobin (Hb), albumin (ALB), alanine aminotransferase and calcium. The in-hospital mortality was not significantly different between patients with and without QTc interval prolongation (2.1% versus 1.3%, P = 0.276). In the subgroup analyses of patients with hepatitis B virus or alcohol alone-related liver cirrhosis, the risk factors included higher bilirubin, creatinine, prothrombin time, international normalized ratio, Child-Pugh score and model for end-stage liver diseases score, and lower RBC, Hb and ALB. In the subgroups analyses of patients with acute upper gastrointestinal bleeding or ascites, the risk factors included lower RBC, Hb and ALB.

CONCLUSIONS

QTc interval prolongation was frequent in liver cirrhosis. Although QTc interval prolongation was positively associated with alcohol-related liver cirrhosis and more severe liver dysfunction, it did not significantly influence the in-hospital mortality.

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.

Recent advances in cirrhotic cardiomyopathy

Cirrhotic cardiomyopathy, a cardiac dysfunction presented in patients with cirrhosis, represents a recently recognized clinical entity. It is characterized by altered diastolic relaxation, impaired contractility, and electrophysiological abnormalities, in particular prolongation of the QT interval. Several mechanisms seem to be involved in the pathogenesis of cirrhotic cardiomyopathy, including impaired function of beta-receptors, altered transmembrane currents, and overproduction of cardiodepressant factors, like nitric oxide, tumor necrosis factor α, and endogenous cannabinoids. Diastolic dysfunction is the first manifestation of cirrhotic cardiomyopathy and reflects the increased stiffness of the cardiac mass, which leads to delayed left ventricular filling. On the other hand, systolic incompetence is presented later, is usually unmasked during pharmacological or physical stress, and predisposes to the development of hepatorenal syndrome. The prolongation of QT is found in about 50 % of cirrhotic patients, but rarely leads to fatal arrhythmias. Cirrhotics with blunted cardiac function seem to have poorer survival rates compared to those without, and the risk is particularly increased during the insertion of transjugular intrahepatic portosystemic shunt or liver transplantation. Till now, there is no specific treatment for the management of cirrhotic cardiomyopathy. New agents, targeting to its pathogenetical mechanisms, may play some role as future therapeutic options.

Arrhythmia risk in liver cirrhosis

Interactions between the functioning of the heart and the liver have been described, with heart diseases affecting the liver, liver diseases affecting the heart, and conditions that simultaneously affect both. The heart is one of the most adversely affected organs in patients with liver cirrhosis. For example, arrhythmias and electrocardiographic changes are observed in patients with liver cirrhosis. The risk for arrhythmia is influenced by factors such as cirrhotic cardiomyopathy, cardiac ion channel remodeling, electrolyte imbalances, impaired autonomic function, hepatorenal syndrome, metabolic abnormalities, advanced age, inflammatory syndrome, stressful events, impaired drug metabolism and comorbidities. Close monitoring of cirrhotic patients is needed for arrhythmias, particularly when QT interval-prolonging drugs are given, or if electrolyte imbalances or hepatorenal syndrome appear. Arrhythmia risk may persist after liver transplantation due to possible QT interval prolongation, persistence of the parasympathetic impairment, post-transplant reperfusion and chronic immunosuppression, as well as consideration of the fact that the transplant itself is a stressful event for the cardiovascular system. The aims of the present article were to provide a review of the most important data regarding the epidemiology, pathophysiology, and biomarkers of arrhythmia risk in patients with liver cirrhosis, to elucidate the association with long-term outcome, and to propose future research directions.

Establishment and validation of ALPH-Q score to predict mortality risk in patients with acute-on-chronic hepatitis B liver failure: a prospective cohort study

Currently, there are no robust models for predicting the outcome of acute-on-chronic hepatitis B liver failure (ACHBLF). We aimed to establish and validate a new prognostic scoring system, named ALPH-Q, that integrates electrocardiography parameters that may be used to predict short-term mortality of patients with ACHBLF. Two hundred fourteen patients were included in this study. The APLH-Q score was constructed by Cox proportional hazard regression analysis and was validated in an independent patient cohort. The area under the receiver-operating characteristic curve was used to compare the performance of different models, including APLH-Q, Child-Pugh score (CPS), model of end-stage liver disease (MELD), and a previously reported logistic regression model (LRM). The APLH-Q score was constructed with 5 independent risk factors, including age (HR = 1.034, 95% CI: 1.007-1.061), liver cirrhosis (HR = 2.753, 95% CI: 1.366-5.548), prothrombin time (HR = 1.031, 95% CI: 1.002-1.062), hepatic encephalopathy (HR = 2.703, 95% CI: 1.630-4.480), and QTc (HR = 1.008, 95% CI: 1.001-1.016). The performance of the ALPH-Q score was significantly better than that of MELD and CPS in both the training (0.896 vs 0.712, 0.896 vs 0.738, respectively, both P < 0.05) and validation cohorts (0.837 vs 0.689, 0.837 vs 0.585, respectively, both P < 0.05). Compared with LRM, APLH-Q also showed a better performance (0.896 vs 0.825, 0.837 vs 0.818, respectively).We have developed a novel APLH-Q score with greater performance than CPS, MELD, and LRM for predicting short-term mortality of patients with ACHBLF.

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.

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.

Drug-induced QT prolongation in cirrhotic patients with transjugular intrahepatic portosystemic shunt

GOALS AND BACKGROUND

Nearly 40% of cytochrome P450 3A (CYP3A) activity is located in the small intestine. An earlier study has shown that cirrhotics with transjugular intrahepatic portosystemic shunts (TIPS) have diminished intestinal CYP3A activity. We hypothesized that oral CYP3A substrates known to prolong QT interval may cause further prolongation of the QT interval in cirrhotic patients with TIPS.

STUDY

A total of 23 patients (9 healthy controls, 6 cirrhotics without and 8 cirrhotics with TIPS) participated in a study that tested this hypothesis using erythromycin as the probe drug. Participants with cirrhosis with and without TIPS were matched for age, sex, race, BMI and etiology of liver disease. Serial electrocardiograms were obtained at baseline, after single dose of erythromycin 500 milligrams, and after 7 days of erythromycin (500 milligrams orally twice daily). QT intervals were measured in 3 consecutive beats in 3 leads and corrected QT intervals (QTc) were obtained using various correction formulae. The maximal QTc change (ΔQTc Max) after single and multiple dose administration was the primary outcome.

RESULTS

At baseline, the QTc intervals (mean±S.E) in cirrhotics with TIPS (418±6 msec) and cirrhosis (431±6 msec) were significantly higher compared with controls (388±9 msec, P=0.021). After a single dose of erythromycin, there was no significant difference among the 3 groups in ΔQTc Max (P=0.7). However, after a 7 day course, cirrhotics with TIPS developed significantly greater ΔQTc Max (179.5±67.8 msec) compared with cirrhotics (31.2±9.5 msec) and healthy controls (38.3±3.3 msec) (P=0.03).

CONCLUSION

This study suggests that patients with TIPS are potentially at increased risk for abnormal QT prolongation when exposed to oral CYP 3A substrates with QT prolonging effect.

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.

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.

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.

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.

Effect of chronic beta-blockade on QT interval in patients with liver cirrhosis

BACKGROUND/AIMS

QT interval prolongation is frequent in cirrhosis, predicts a poor prognosis and may trigger severe ventricular arrhythmias. Our aim was to evaluate the effect of chronic beta-blockade on QT prolongation.

METHODS

Clinical and laboratory evaluation, ECG and hepatic vein pressure gradient (HVPG) measurement were performed in 30 cirrhotic patients before and 1-3 months after prophylactic nadolol. QT was corrected for heart rate by the cirrhosis-specific formula and other formulas.

RESULTS

QT(cirrhosis) was prolonged in 10 patients (33%); HVPG was increased in all cases. QT(cirrhosis) was correlated with the Child-Pugh score (r=0.40; p=0.027). Nadolol shortened QT interval only with the Bazett formula (p=0.01), remaining unchanged with the other formulas. The QT interval shortened only if prolonged at baseline (from 473.3+/-5.5 to 458.4+/-6.5 ms; p=0.007), while it lengthened when normal (from 429.8+/-3.1 to 439.3+/-2.9 ms; p=0.01). QTc changes were directly related to the baseline value (p<0.001). HVPG decreased from 19.4+/-0.8 to 15.6+/-1.3 mmHg (p=0.004). The HVPG changes did not correlate with QTc changes.

CONCLUSIONS

Chronic beta-blockade shortens the QT interval only in patients with prolonged baseline values, and this is likely due to a direct cardiac effect.

Q-T interval (QT(C)) in patients with cirrhosis: relation to vasoactive peptides and heart rate

OBJECTIVE

Prolonged Q-T interval (QT) has been reported in patients with cirrhosis who also exhibit profound abnormalities in vasoactive peptides and often present with elevated heart rate (HR). The aim of this study was to relate QT to the circulating level of endothelins (ET-1 and ET-3) and calcitonin gene-related peptide (CGRP) in patients with cirrhosis. In addition, we studied problems with HR correction of QT.

MATERIAL AND METHODS

Forty-eight patients with cirrhosis and portal hypertension were studied during a haemodynamic investigation. Circulating levels of ETs and CGRP were determined by radioimmunoassays. Correction of QT for HR above 60 beats per min was performed using the methods described by Bazett (QT(C)) and Fridericia (QT(F)).

RESULTS

Prolonged QT(C) (above 440 ms), found in 56% of the patients, was related to the presence of significant portal hypertension and liver dysfunction (p < 0.05 to 0.001), but not to elevated ET-1, ET-3 or CGRP. When corrected according to Bazett, QT(C) showed no significant relation to differences in HR between patients (r = 0.07, ns). QTF showed some undercorrection of HR (r = -0.36; p < 0.02). During HR variation in the individual patient, QT(C) revealed a small but significant overcorrection (2.6 ms per heartbeat per min; p < 0.001). This value was significantly (p < 0.02) smaller with QTF (1.2 ms per heartbeat per min).

CONCLUSIONS

The prolonged QT(C) in cirrhosis is related to liver dysfunction and the presence of portal hypertension, but not to the elevated powerful vasoconstrictor (ET-1) or vasodilator (CGRP, ET-3) peptides. The problems with correction of the QT for elevated HR in cirrhosis are complex, and the lowest HR should be applied for determination of the QT.

Incidence of severe ventricular arrhythmias during pulmonary artery catheterization in liver allograft recipients

Liver allograft recipients may develop a hyperdynamic circulation and cardiac electrophysiologic abnormalities. The incidence of severe ventricular arrhythmias in liver allograft recipients during pulmonary artery (PA) catheterization was determined. One hundred five liver allograft recipients were studied prospectively; 5 of the patients with preexisting valvular heart disease, ischemic heart disease, or arrhythmias were excluded. Severe ventricular arrhythmia, defined as 3 or more consecutive ventricular premature beats occurring at a rate of >100 per minute, was observed in 37.0% of the patients during insertion of the catheter and in 25.0% of the patients during removal of the catheter. Two patients developed ventricular tachycardia, and 2 developed ventricular fibrillation; the arrhythmias in these 4 patients did not respond to appropriate pharmacological treatment but resolved promptly after removal of the PA catheter. The catheter transit time from the right ventricle to the pulmonary capillary wedge position was longer in patients with severe ventricular arrhythmia than in those without this arrhythmia (91.6+/-103.6 s versus 53.3+/-18.4 s, P<0.05). In conclusion, patients undergoing liver transplantation have a high risk of developing a ventricular arrhythmia during PA catheterization.

Diurnal variation and dispersion in QT interval in cirrhosis: relation to haemodynamic changes

BACKGROUND/AIMS

A long QT(C) interval has been described in a substantial fraction of patients with cirrhosis, but information on QT variation and dispersion is sparse. The aim was to determine QT variation with time and QT dispersion (QT(disp)).

METHODS

The study population comprised 23 patients with cirrhosis, undergoing a haemodynamic investigation. 24-h 12 lead Holter monitoring provided information on QT and heart rate variability.

RESULTS

Mean QT(C) was above upper normal limit (440 ms(1/2)) in eleven patients (47%) and significantly higher than in controls (441 vs 400 ms(1/2), p<0.01). The minimum value of QT(C) (but not the maximum value) showed a significant diurnal variation both in cirrhosis and controls. QT(disp) in cirrhosis and controls was similar (33 vs 36 ms, ns), but related to indicators of liver dysfunction, central circulation time, and arterial blood pressure (r=0.44-0.58, p=0.03-0.001). No diurnal variation of QT(disp) was found in cirrhosis. Heart rate variability was reduced with a significant relation to central hypovolaemia (r=0.55, p=0.01).

CONCLUSIONS

Twenty-four hours QT(C) is prolonged in a substantial fraction of patients with cirrhosis, but with normal diurnal variation. The combination of long QT(C) and normal QT(disp) suggests delayed myocyte repolarisation on the cellular level, rather than temporal and spatial heterogeneity in the myocardial wall.