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.
These data provide evidence that aldosterone blockade by long-term K-Canrenoate administration improves hepatic hemodynamics by lowering HVPG and ameliorates cardiac structure and function by favoring a reduction in LVWT and LVEDV as well. They also show, however, that this therapeutic intervention neither improves left ventricular diastolic dysfunction nor exerts sympathoinhibitory effects.
Overactivity of the sympathetic nervous system and portal hypertension are key factors in the development of ascites in cirrhosis. The sympathoexcitation that characterizes the more advanced stages of liver diseases is less clearly defined in preascitic cirrhosis. We measured sympathetic nerve traffic to skeletal muscle (peroneal nerve) and to skin districts by microneurography in (1) 12 Child class A cirrhotic patients with clinically significant portal hypertension (portal pressure gradient > 10 mm Hg, 14.8 ؎ 1.2 mm Hg, mean ؎ SEM) but without actual or previous ascites, (2) 16 Child class C cirrhotic patients with tense ascites, and (3) 10 patients with mild congestive heart failure, a condition paradigmatic of a marked sympathetic activation. Muscle sympathetic nerve traffic was markedly increased in Child class C subjects as compared with controls (23.9 ؎ 1.6 bursts/min, P < .01) and superimposable to that recorded in heart failure patients (52.9 ؎ 4.7 vs. 60.3 ؎ 2 bursts/min, P ؍ not significant). Muscle sympathetic nerve traffic was also increased in Child class A subjects (41.6 ؎ 2 bursts/min, P < .01 vs. controls) although to a lesser extent (P < .05 vs. Child class C patients). Skin sympathetic nerve traffic was within the normal range in all patients. Neurohormones were all markedly increased in Child class C subjects. Only norepinephrine was increased in Child class A patients. Our data show that sympathetic nerve traffic activation (1) is already detectable in Child class A cirrhosis when clinically significant portal hypertension is present but ascites never developed and (2) Cirrhosis is accompanied by an increase in sympathetic activity 1 as shown by the observation that in this condition plasma norepinephrine, 2-5 norepinephrine spillover from neuroeffector junctions, 6 and muscle sympathetic nerve traffic as directly quantified by microneurography 7-9 are all increased. The sympathoactivation accompanying cirrhosis has not yet been thoroughly characterized, however. For example, it is not yet clear whether the sympathoactivation is a pathophysiologic feature of cirrhosis throughout its course or if it just appears when fluid retention, ascites, or the hepatorenal syndrome dramatically alter circulating blood volume. 10 It is also not clear whether the sympathoactivation is generalized to the entire cardiovascular system or if it involves some vascular beds but not others.The aim of the present study has been to provide information on these two issues; that is, whether sympathetic activity is increased in earlier stages of cirrhosis in which portal pressure is increased but ascites has never developed and whether in either preascitic and more advanced cirrhosis the sympathetic activation has a generalized or more regional distribution.
PATIENTS AND METHODSStudy Population. This study was performed on a total of 48 subjects. Twenty-eight patients had cirrhosis and portal hypertension with different degrees of liver impairment as assessed by the ChildPugh classification. Twelve patients were Ch...
In patients with chronic HCV hepatitis, fibrosis was associated with hyperadiponectinemia. Chronic HCV-infected hepatocytes showed reduced ADIPOR1 expression, suggesting a pattern of adiponectin resistance.
Cirrhotic cardiomyopathy is a recently identified pathological condition defined as "a chronic cardiac dysfunction in patients with cirrhosis characterized by blunted contractile responsiveness to stress and/or altered diastolic relaxation with electrophysiological abnormalities, in the absence of known cardiac disease". Overall there seems to be a link between the progression of liver function impairment, the development of portal hypertension and the degree of hyperdynamic circulation, the hallmark of the deranged cardiovascular function in advanced liver diseases. Although mechanical factors contribute to much of the increased resistance within the liver in portal hypertension, there is clearly a vasculogenic component to the development, perpetuation and progression of this syndrome as well. The vascular component of portal hypertension includes an increase in splanchnic blood flow, as well as an increase in intrahepatic vascular resistance. Dysregulation of the nitric oxide system appears to play a key role in both these processes with a paradoxical reduction of intrahepatic availability despite increased disposal in the splanchnic and other vascular districts with adverse effects on cardiac function and structure. Nevertheless, other putative mediators of cardiac damage in cirrhosis have been proposed and their role in the pathogenesis of cirrhotic cardiomyopathy investigated. This review involves a discussion of data achieved on pathogenesis and clinical features of cirrhotic cardiomyopathy but mainly focuses on considerations on potential therapeutic targets, in the light of the evidence that this mainly subclinical condition merges to clinical relevance when challenged with those therapeutic interventions and procedures currently employed to treat the major complications of cirrhosis that might produce a negative impact on the cardiovascular system.
Preliminary results suggest that in patients with cirrhosis and early HCC, perfusion CT is a feasible technique for noninvasive assessment of tumor vascularity.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.