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

What Every Intensivist should Know about Impairment of Cardiac Function and Arrhythmias in Liver Disease Patients: A Review

Objectives

Impairment of cardiac function and arrhythmias often coexist in patients with liver diseases. Many studies have proved this coexistence and put forward various theories toward its pathophysiology. This narrative review tries to find the answers with supporting evidence on five main questions:

Materials and methods

Clinical evidence was obtained by using search engines, namely, Cochrane Library, PubMed, and Google Scholar. Studies published in journals in the English language, between January 1969 and December 2019, which mentioned the relationship between cardiac arrhythmia and liver disease, were included. We used the keywords: jaundice, bilirubin, arrhythmia, ECG, QTc interval, QT dispersion, liver, and cirrhosis. Relevant animal or human studies answering the five main questions were extracted and reviewed.

Conclusion

The evidence included in our review sheds light on the fact that approximately 50% of liver cirrhosis cases develop cirrhotic cardiomyopathy (CC) and there has been an association between liver abnormalities and cardiac pathology. The present review also supports that there exists a strong association between high levels of serum bilirubin levels and cardiac arrhythmias, QTc value can be relied upon as a risk factor for predicting imminent arrhythmias, and that it is associated with mortality. Its basic pathophysiology can be explained by the potential action of bile acids in prolonging the QT interval. It also causes cardiac hypertrophy and apoptosis of cardiomyocytes leading to cardiac dysfunction.

How to cite this article

Arya S, Kumar P, Tiwari B, Belwal S, Saxena S, Abbas H. What Every Intensivist should Know about Impairment of Cardiac Function and Arrhythmias in Liver Disease Patients: A Review. Indian J Crit Care Med 2020;24(12):1251–1255.

Cirrhotic Cardiomyopathy After Transplantation: Neither the Transient Nor Innocent Bystander

Cirrhotic cardiomyopathy in end-stage liver disease is currently characterized by blunted contractile systolic response to stress with or without diastolic dysfunction in the absence of known heart disease. Since the establishment of the diagnostic criteria of cirrhotic cardiomyopathy in 2005, there have been multiple studies regarding its pathophysiology and pretransplant clinical course. The data regarding the post-transplant course of this entity are sparse. This review addresses the course and prognosis of the elements of cirrhotic cardiomyopathy after liver transplantation (LT). To this end, there is limited compelling evidence demonstrating the reversibility of this entity post-LT. Cirrhotic cardiomyopathy may, in fact, increase the risk of post-transplant complications. This review reveals a need to refine the diagnostic criteria of cirrhotic cardiomyopathy in view of the remarkable progress in the sphere of echocardiographic evaluation of systolic and diastolic dysfunction. The post-transplant course and outcomes related to cirrhotic cardiomyopathy may be better evaluated in the setting of updated diagnostic criteria.

Q-T interval prolongation in cirrhosis: Relationship and severity

Background

Cirrhosis as the final stage of progressive fibrosis of liver can affect other organs such as lungs, kidneys and heart. "Cirrhotic cardiomyopathy" involves the electrophysiological abnormalities such as QT interval prolongation. We assessed correlation between corrected QT interval prolongation and severity of cirrhosis based on Child Classification in each ECG lead.

Methods

In this case-control study, the patients attending the outpatient clinic and inpatient department of internal medicine of Velayat Hospital in Qazvin were enrolled from September 2014 to July 2015. Total samples were 74 patients, half of which were used as controls. Cirrhosis severity was determined as per Child Classification. Both groups had Ca²⁺, Mg²⁺, K⁺ tested and 12- lead ECG was obtained. The QT interval was corrected by two different formulas: (1) QTc=QT/√RR (QTc₁); (2) QTc=QT+1.75 (heart rate-60) (QTc₂). To analyze the data, the software SPSS Version 16 and Mann-Whitney, Pearson's chisquare test-Kruskal-Wallis, and t-tests were used.

Results

The mean of QTc₁ and QTc₂ was longer in cirrhotics than the control group. There was a significant correlation between Child score and length of QTc₁ in leads: III (p=0.032), AVL (p=0.041), V2 (p=0.049), V6 (p=0.015). There were significant differences in length of QTc₁ in leads: V3 (p=0.031) and V6 (p=0.021); and QTc₂ in lead V3 (p=0.039) between Child Classification.

Conclusions

Cirrhosis can induce QTc interval prolongation. Lead V3 has statistically significant correlation with the severity of cirrhosis based on child classification. We propose that QT interval prolongation be added as a criterion for prioritizing liver transplantation.

Rare Incidence of Ventricular Tachycardia and Torsades de Pointes in Hospitalized Patients With Prolonged QT Who Later Received Levofloxacin: A Retrospective Study

OBJECTIVE

To determine the incidence of ventricular tachycardia and ventricular fibrillation in patients with prolonged corrected QT interval (QTc) who received levofloxacin through retrospective chart review at a tertiary care teaching hospital in the United States.

PATIENTS AND METHODS

We selected 1004 consecutive hospitalized patients with prolonged QTc (>450 ms) between October 9, 2009 and June 12, 2012 at our institution. Levofloxacin was administered orally and/or intravenously and adjusted to renal function in the inpatient setting. The primary outcome measure was sustained ventricular tachycardia recorded electrocardiographically.

RESULTS

With a median time from the start of levofloxacin use to hospital discharge (or death) of 4 days (range, 1-94 days), only 2 patients (0.2%; 95% CI, 0.0%-0.7%) experienced the primary outcome of sustained ventricular tachycardia after the initiation of levofloxacin use.

CONCLUSION

In this study, the short-term risk for sustained ventricular tachycardia in patients with a prolonged QTc who subsequently received levofloxacin was very rare. These results suggest that levofloxacin may be a safe option in patients with prolonged QTc; however, studies with longer follow-up are needed.