Effect of liver transplantation on QT interval prolongation and autonomic dysfunction in end-stage liver disease

Liver cirrhosis and arterial hypertension

Characteristic findings in patients with cirrhosis are vasodilatation with low overall systemic vascular resistance, high arterial compliance, increased cardiac output, secondary activation of counter-regulatory systems (renin-angiotensin-aldosterone system, sympathetic nervous system, release of vasopressin), and resistance to vasopressors. The vasodilatory state is mediated through adrenomedullin, calcitonin gene-related peptide, nitric oxide, and other vasodilators, and is most pronounced in the splanchnic area. This constitutes an effective (although relative) counterbalance to increased arterial blood pressure. This review considers the alterations in systemic hemodynamics in patients with cirrhosis in relation to essential hypertension and arterial hypertension of the renal origin. Subjects with arterial hypertension (essential, secondary) may become normotensive during the development of cirrhosis, and arterial hypertension is rarely manifested in patients with cirrhosis, even in cases with renovascular disease and high circulating renin activity. There is much dispute as to the understanding of homoeostatic regulation in cirrhotic patients with manifest arterial hypertension. This most likely includes the combination of vasodilatation and vasoconstriction in parallel.

Cardiopulmonary complications in chronic liver disease

Patients with cirrhosis and portal hypertension exhibit characteristic cardiovascular and pulmonary hemodynamic changes. A vasodilatatory state and a hyperdynamic circulation affecting the cardiac and pulmonary functions dominate the circulation. The recently defined cirrhotic cardiomyopathy may affect systolic and diastolic functions, and imply electromechanical abnormalities. In addition, the baroreceptor function and regulation of the circulatory homoeostasis is impaired. Pulmonary dysfunction involves diffusing abnormalities with the development of the hepatopulmonary syndrome and portopulmonary hypertension in some patients. Recent research has focused on the assertion that the hemodynamic and neurohumoral dysregulation are of major importance for the development of the cardiovascular and pulmonary complications in cirrhosis. This aspect is important to take into account in the management of these patients.

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

BACKGROUND/AIMS

The Q-T(c) interval is prolonged in a substantial fraction of patients with cirrhosis, thus indicating delayed repolarisation. However, no information is available in mild portal hypertensive patients. We therefore determined the Q-T(c) interval in cirrhotic patients with hepatic venous pressure gradient (HVPG) < 12 mmHg.

METHODS

Forty-four patients with cirrhosis and HVPG < 12 mmHg underwent a haemodynamic study. They were compared with 36 cirrhotic patients with clinically significant portal hypertension (HVPG> or = 12 mmHg) and controls without liver disease.

RESULTS

The fraction with prolonged Q-T(c) interval (> 0.440 s(1/2)) was similar in the two cirrhotic groups (49 vs 50%, ns) and significantly above that of the controls (5%, P < 0.005). Q-T(c) was normal in patients with normal HVPG. Likewise, mean Q-T(c) was 0.449 and 0.447 s(1/2) in the two cirrhotic groups (ns), values which are significantly above that of the controls (0.410 s(1/2), P < 0.01). In the mild portal hypertensive group, the Q-T(c) interval was inversely related to indicators of liver function, such as indocyanine green clearance (r = -0.34, P < 0.02).

CONCLUSIONS

Delayed repolarisation of the myocardium already occurs in a substantial fraction of patients with cirrhosis with only a mild increase in portal pressure. The prolonged Q-T(c) interval may be related to liver dysfunction and to the presence of portal hypertension.

Cholestatic liver disease modulates susceptibility to ischemia/reperfusion-induced arrhythmia, but not necrosis and hemodynamic instability: the role of endogenous opioid peptides

BACKGROUND/AIMS

Acute cholestasis is associated with cardiovascular complications, which mainly manifest during stressful conditions. The goal of this study is to evaluate susceptibility of 7-day bile duct-ligated rats to ischemia/reperfusion-induced injury.

METHODS

Sham-operated and cholestatic rats, treated with daily normal saline, L-NAME (a non-selective NO synthase inhibitor) naltrexone, or both L-NAME and naltrexone were subjected to 30 min of ischemia followed by 2 h of reperfusion.

RESULTS

Cholestatic rats demonstrated significant bradycardia, hypotension (P < 0.01), and QT prolongation (P < 0.001). The incidence of premature ventricular contractions (P < 0.01), incidence and duration of ventricular tachycardia (P < 0.05), but not ventricular fibrillation, were significantly lower in cholestatic rats. There was no significant difference in hemodynamic instability and infarct size between the groups. L-NAME corrected QT prolongation in cholestatic rats (P < 0.05), with no effect on heart rate, blood pressure and arrhythmia. Naltrexone restored normal heart rate (P < 0.05), blood pressure (P < 0.05) and susceptibility to arrhythmia (P < 0.05) in cholestatic animals, with no significant effect on QT interval. L-NAME and naltrexone co-administration corrected bradycardia (P < 0.05), hypotension (P < 0.05), QT prolongation (P < 0.05) and abolished resistance of cholestatic rats against arrhythmia (P < 0.05).

CONCLUSIONS

This study suggests that short-term cholestasis is associated with resistance against ischemia/reperfusion-induced arrhythmia, which depends on availability of endogenous opioids.

Effect of cirrhosis and liver transplantation on the gender difference in QT interval

The effect of gender on the QT interval in patients with cirrhosis before and after liver transplantation and the relation between the QT interval and changes in gender hormones after liver transplantation were assessed. The study showed that (1) physiologic gender difference in the QTc interval is abolished in cirrhosis, and it is not restored after liver transplantation, and (2) gender hormone concentrations had no effect on the QTc interval.

Hypertension and liver disease

Arterial hypertension is a common disorder with a frequency of 10% to 15% in subjects in the 40- to 60-year age group. Yet most reports find the prevalence of arterial hypertension in patients with chronic liver disease (cirrhosis) much lower. In this review, we consider the alterations in systemic hemodynamics in cirrhosis. The most characteristic findings in cirrhotic patients are vasodilatation with low systemic vascular resistance, increased cardiac output, high arterial compliance, secondary activation of counterregulatory systems (sympathetic nervous system, renin-angiotensin-aldosterone system, neuropituitary release of vasopressin), and resistance to vasopressors. The vasodilatory state is mediated through nitric oxide, calcitonin gene-related peptide, adrenomedullin, and other vasodilators, and is most pronounced in the splanchnic area. This constitutes an effective (although relative) counterbalance to increased arterial blood pressure. Subjects with established arterial hypertension (essential, secondary) may become normotensive during the development of cirrhosis, and arterial hypertension is rarely manifested in patients with cirrhosis, even in cases with renovascular disease and high circulating renin activity. There is much dispute as to the understanding of homeostatic regulation in cirrhotic patients with manifest arterial hypertension. This is a topic for future research.

Effects of orthotopic liver transplantation on the corrected QT interval in patients with end-stage liver disease

Autonomic dysfunction is a recognized complication of end-stage liver disease (ESLD) associated with a poor prognosis. The corrected QT interval (QTc) on electrocardiogram is a marker of autonomic function. A few small studies have suggested that QTc may normalize with the return of liver function after orthotopic liver transplantation. We sought to determine how transplantation affects the QTc in patients with ESLD. The QTc from the pretransplantation evaluation of 46 patients with ESLD was compared with the QTc at 4-month posttransplantation follow-up. Other factors that can influence autonomic function also were evaluated. Most patients with ESLD (54%) showed a prolonged QTc (> or = 440 msec) at the pretransplantation evaluation (451 +/- 45 msec) that improved to within the normal range at posttransplantation follow-up (418 +/- 18 msec; P < 0.001). There was no relationship between QTc prolongation and Child-Turcotte-Pugh score, Model for End-Stage Liver Disease score, diabetes mellitus, age, or etiology of liver disease. Most patients with ESLD and a prolonged QTc will have a significant improvement in QTc after transplantation; however, 6.5% of patients in our study had a worsening of QTc after transplantation.

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

BACKGROUND/AIMS

Earlier studies have shown a prolonged frequency-adjusted Q-T interval (QTc>0.440 s(1/2)) in a substantial fraction of patients with cirrhosis. The effect of beta-blockade on QTc is unknown, and its determination was the aim of the study.

METHODS

Seventeen patients with cirrhosis received 80 mg propranolol orally during a haemodynamic investigation with measurements at baseline and 90 min after propranolol ingestion.

RESULTS

Beta-blockade reduced cardiac output (-21%, P<0.001), heart rate (-20%, P<0.001), and the hepatic venous pressure gradient (HVPG, -17%, P<0.02). The mean QTc=0.460 s(1/2) was prolonged compared to 0.410 s(1/2) in age-matched controls (P<0.01). Whereas QTc decreased during beta-blockade in the cirrhotic patients (from 0.460 to 0.440 s(1/2), P<0.01), no effect was found in the subgroup with normal QTc (0.429 vs. 0.422 s(1/2), ns), and a reduction was seen in the patients with prolonged QTc (from 0.488 to 0.456 s(1/2), P<0.01). The percentage decrease in QTc was related to the reduction in HVPG (r=0.48, P=0.03) and cardiac output (r=0.56, P=0.02).

CONCLUSIONS

Acute non-selective beta-blockade reduces prolonged QTc towards normal values in patients with cirrhosis. The clinical significance of QTc reduction in arrhythmia is a topic for future research.

Autonomic and peripheral neuropathy in endstage liver disease and following liver transplantation

Severe chronic liver disease may be associated with a peripheral somatic and an autonomic neuropathy. There are only a limited number of reports on the incidence and features of these neuropathies. In addition the effects of liver transplantation on these neuropathies have not been well studied. We examined peripheral somatic and autonomic nerve function in 42 patients with endstage liver disease prior to transplantation and also examined the effect of liver transplantation on these neuropathies in 14 patients. Peripheral somatic neuropathy (93%) and autonomic neuropathy (50%) were common in patients with endstage liver disease and were more frequent than previously reported. Abnormalities improved in some patients after liver transplantation, particularly if there was return of normal hepatic function.

Prolongation of QTc interval: relationship with etiology and severity of liver disease, mortality and liver transplantation

BACKGROUND

A prolonged QTc interval has been reported in patients with liver disease. The objectives of our study were to determine whether a prolonged QTc interval was an independent predictor of mortality in patients with cirrhosis and to examine the effect of liver transplantation (LT) on QTc interval.

PATIENTS AND METHODS

We retrospectively studied two cohorts of patients - QTc interval was measured in 409 patients (pre-transplant group), and in 162 patients (transplant group) before and 6 months after LT. QT interval (mean) corrected (QTc) for ventricular rate was read from a 12-lead EKG. Patients with known cardiovascular disease or other risk factors that are known to cause a prolonged QTc interval were excluded.

RESULTS

Pre-transplant group. One hundred and sixty-two patients (40%) had a prolonged QTc interval (>440 ms). By binary logistic regression, age (P=0.005), alcoholic cirrhosis (P=0.007) and Child-Pugh scores (P=0.007) were independent predictors of prolonged QTc interval. Sixty-six patients died during a mean follow-up of 8.9 years. Although the Kaplan-Meier survival curve showed a lower survival in patients with a prolonged QTc interval (P=0.03 by log rank test), when survival was adjusted for the Child-Pugh score by Cox regression survival analysis, there were no survival differences in patients with and without prolonged QTc interval. Cox regression analysis showed that the Child-Pugh score (hazard ratio 1.5, CI 1.3-1.6, s<0.001) was the only independent predictor of survival. Transplant group. In this cohort, 91 patients (56%) had prolonged QTc (>440 ms) before LT. Mean QTc improved significantly after LT (429 +/- 29 ms vs. 450 +/- 39 ms P<0.002). Of the 91 patients with prolonged QTc, 50 (55%) normalized, three (3.3%) remained unchanged, 12 (13.3%) showed further prolongation, and 26 (28%) showed improvement but remained above normal limits. An additional nine patients who had normal QTc before LT developed prolonged QTc (>440 ms) after LT.

CONCLUSION

A prolonged QTc interval was common in patients with cirrhosis, but its presence had no independent effect on mortality. Prolonged QTc returns to normal values in about half of the patients after LT, suggesting that liver disease plays a role, but may not be the only factor in the pathogenesis of prolonged QTc.

QT interval in patients with non-cirrhotic portal hypertension and in cirrhotic patients treated with transjugular intrahepatic porto-systemic shunt

BACKGROUND/AIMS

A prolonged QT interval is frequent in chronic liver disease and its aetiology remains unsettled. The study's aim was to assess the role of portal hypertension in the pathogenesis of QT prolongation.

METHODS

We measured the QT interval in: (1) 10 patients with non-cirrhotic portal hypertension (NCPH) and preserved liver function; (2) 19 cirrhotic patients before, 1-3 and 6-9 months after transjugular intrahepatic porto-systemic shunt (TIPS) insertion.

RESULTS

Baseline corrected maximum QT interval (QTcmax) was prolonged (>440 ms) in eight NCPH and 16 cirrhotic patients, and its value did not differ between the two groups (453+/-8 vs. 465+/-6 ms, P=NS). No patients showed an abnormal baseline QT dispersion. In cirrhotic individuals, QTcmax further increased 1-3 months after TIPS (P=0.042), thereafter remaining steadily elevated. QT dispersion only increased at the second post-TIPS determination (P=0.030). Such changes occurred despite no deterioration of liver function, plasma electrolytes and haemoglobin.

CONCLUSIONS

QT interval is frequently prolonged in patient with both non-cirrhotic and cirrhotic portal hypertension and portal decompression by TIPS worsens this abnormality. These results suggest that the porto-systemic shunting is responsible for the altered ventricular repolarisation possibly through a dumping into the systemic circulation of splanchnic-derived cardioactive substances.

Dyssynchronous electrical and mechanical systole in patients with cirrhosis

BACKGROUND/AIMS

Previous investigations have shown a prolonged QT interval in some patients with cirrhosis. The aim of this study was to investigate the relation between electrical and mechanical systole in patients with different degrees of severity of cirrhosis.

METHODS

Forty-eight patients with cirrhosis and portal hypertension, studied during a haemodynamic investigation, were compared to 17 controls.

RESULTS

A prolonged QTc (above 0.440 s(1/2)) was found in 37% of the cirrhotic patients vs. 5.9% in the controls (P=0.03), and there was a correlation to liver dysfunction (P<0.02). A direct relation between QT and time of mechanical systole (tS) was observed in controls (r=0.58, P<0.01), and cirrhotic patients (r=0.44, P<0.002). In patients with a prolonged QTc interval, the difference between electrical and mechanical systole time was substantially longer than in patients with a normal QTc interval (0.078 vs. 0.031 s, P<0.005). The QT values were related to markers of hyperdynamic circulation (r=-0.48 to 0.56, P<0.05-0.001). CONCLUSIONS; Prolonged repolarization, as evidenced by prolonged QTc, is related to both impaired liver function and systemic circulatory dysfunction. In addition these patients have alterations in the cardiac excitation-contraction relation with compromised association between electrical and mechanical function.

Prevalence of autonomic dysfunction in cirrhotic and noncirrhotic portal hypertension

OBJECTIVE

Autonomic dysfunction is common in patients with cirrhosis of the liver, but more so in patients with decompensated state, and is associated with increased mortality. We evaluated the presence and extent of autonomic dysfunction in patients with extrahepatic portal venous obstruction (EHPVO) and noncirrhotic portal fibrosis (NCPF), diseases with relatively preserved liver functions.

METHODS

Heart rate variability in response to standing, deep breathing, and Valsalva maneuver and blood pressure response to sustained handgrip and standing were studied in 18 patients with EHPVO (13 mol/L, 5 F, mean age 15.2 +/- 6 yr), 12 patients with NCPF (5 mol/L, 7 F, mean age 26.4 +/- 8 yr), 15 patients with cirrhosis (7 mol/L, 8 F, mean age 12.6 +/- 6 yr), and 17 healthy controls (11 mol/L, 6 F, mean age 18.6 +/- 3 yr). Time-domain parameters of heart rate variability on 24-h ambulatory monitoring were assessed in all the patients.

RESULTS

Autonomic dysfunction was observed in 67% of EHPVO, 25% of NCPF, and 80% of cirrhotic subjects but none of the healthy controls (p < 0.05). Four of five time-domain heart rate variability indices showed significant abnormalities in patients with EHPVO (p < 0.05) and cirrhosis (p < 0.05), when compared with patients with NCPF and healthy controls.

CONCLUSIONS

Autonomic dysfunction is frequently encountered in patients with EHPVO and cirrhosis, and the presence of autonomic dysfunction in patients with noncirrhotic portal hypertension suggests a primary role of portal hypertension per se in the dysfunction.

Rapid improvement of autonomic and peripheral neuropathy after liver transplantation: a single case report

Peripheral and autonomic neuropathies are known but often unrecognized associations of cirrhosis from any cause. The pathogenesis of these effects are ill understood. Liver transplantation has been shown to reverse autonomic manifestations, but little evidence exists for an effect on peripheral neuropathy. This case report documents improvement in peripheral and autonomic neuropathy in a 40-year-old man with hepatitis B virus--related cirrhosis. A return to normal neurophysiological function was seen within 9 months of successful liver transplantation, suggesting a metabolic, rather than a structural, cause of such changes in the peripheral nervous system.

Cirrhotic cardiomyopathy: a pathophysiological review of circulatory dysfunction in liver disease

The systemic circulation in patients with cirrhosis is hyperdynamic with an increased cardiac output and heart rate and a reduced systemic vascular resistance as the most pronounced alterations. The concomitant cardiac dysfunction has recently been termed "cirrhotic cardiomyopathy", which is an entity different from that seen in alcoholic heart muscle disease. Clinically, these patients present with sodium fluid retention and strain often unmasks the presence of latent heart failure. No specific treatment can yet be recommended but caution should be used with respect to procedures that may stress the heart such as shunt implantation and liver transplantation.

Prolonged QTc interval and its relationship to autonomic cardiovascular reflexes in patients with cirrhosis

BACKGROUND/AIMS

We have previously shown that an abnormality in cardiac autonomic reflexes (AN) is an independent predictor of mortality in patients with chronic liver disease. Aim of this study was to determine whether there was an association between prolonged QTc interval and cardiac AN.

METHODS

Cardiac AN and QTc interval were determined in 130 patients (Child A 42, B 53, C 35) with alcoholic and non-alcoholic liver disease.

RESULTS

Prolonged QTc (>440ms) was seen in 58 (Child A 30%, B 46%, C 60%, P=0.04) patients. Autonomic tests were normal in 21%, borderline abnormal in 36% and definitely abnormal in 43%. QTc correlated with albumin (P<0.001), prothrombin time (P=0.003) and Child-Pugh score (P<0.001), but not with Valsalva ratio, heart rate variation with 6 breath/min breathing, tilt table or isometric exercise. By logistic regression analysis, QTc correlated only with Child-Pugh score (P<0.001). Mean QTc of 34 who died during the follow up was higher than survivors. Cox regression analysis showed that only Child-Pugh score and AN were independent predictors of mortality.

CONCLUSIONS

Prolonged QTc seen in liver disease is independent of their cardiac autonomic function, but is related to the severity of the liver disease.

Report of a life-threatening arrhythmia after hospital discharge in a liver transplant recipient with previously unknown congenital long QT syndrome

The long QT syndrome affects heart rhythm by prolonging ventricular repolarisation; it is potentially life-threatening since it can evolve into torsades de pointes (a polymorphic ventricular tachycardia) and/or ventricular fibrillation. The case is presented of a 55-year-old liver transplant recipient with a genetically determined long QT syndrome not detected by the standard preoperative cardiological evaluation. It was mild in the immediate post-operative period but developed into torsades de pointes after discharge, probably as a result of therapy. This case was particularly challenging because the first arrhythmic episodes were short and electocardiographically silent, and thus the related faints were thought to have a neurological basis. When the true cause emerged during a monitored episode of torsades de pointes, electric defibrillation was used to restore sinus rhythm and isoproterenol administered to increase heart rate and thus shorten the prolonged QT interval Long-term control was obtained by means of an implantable intracardiac defibrillator. In orthotopic liver transplant recipients with long QT syndrome, particular attention should be given to post-operative therapy as some routinely used drugs can trigger life-threatening ventricular arrhythmias.

Autonomic dysfunction and hyperdynamic circulation in cirrhosis with ascites

Patients with advanced cirrhosis frequently show hemodynamic abnormalities. Autonomic dysfunction (AD) is also common and, owing to the importance of autonomic function in cardiovascular homeostasis, it may be involved in the pathogenesis of the hyperdynamic circulation. We, therefore, evaluated the hemodynamic status and autonomic function in 30 patients with cirrhosis, most of them with an advanced stage of the disease. Autonomic function was assessed with 7 cardiovascular tests exploring the vagal or sympathetic function. Each test was scored from 1 to 3 (normal, borderline, altered). Cardiac index (CI) was measured by an echocardiogram. Twenty-four (80%) patients showed an AD, this being definite in 14 (47%) patients. A vagal dysfunction (VD) was found in 19 patients (63%), this being definite in 11 patients (37%), and a sympathetic dysfunction (SD) in 7 patients (definite in 3 [10%] patients). The patients with AD showed a faster heart rate (P =.021), lower indicized peripheral vascular resistance (P =.013), and increased CI (P =.004) than patients without AD whereas mean arterial pressure did not differ. Similar results were seen by grouping patients according to the VD. AD score was directly correlated with heart rate (r = 0.53; P =.002) and CI (r = 0.45; P =. 016), and inversely correlated with peripheral vascular resistance (r = 0.46; P =.013). Even closer correlations were found with vagal score. AD (mainly VD) may be involved in the pathogenesis of the hyperdynamic circulatory syndrome of patients with advanced cirrhosis.

Abnormalities of the QT interval in primary disorders of autonomic failure

BACKGROUND

Experimental evidence shows that activation of the autonomic nervous system influences ventricular repolarization and, therefore, the QT interval on the ECG. To test the hypothesis that the QT interval is abnormal in autonomic dysfunction, we examined ECGs in patients with severe primary autonomic failure and in patients with congenital dopamine beta-hydroxylase (DbetaH) deficiency who are unable to synthesize norepinephrine and epinephrine.

SUBJECTS AND METHODS

Maximal QT and rate-corrected QT (QTc) intervals and adjusted QTc dispersion [(maximal QTc - minimum QTc on 12 lead ECG)/square root of the number of leads measured] were determined in blinded fashion from ECGs of 67 patients with primary autonomic failure (36 patients with multiple system atrophy [MSA], and 31 patients with pure autonomic failure [PAF]) and 17 age- and sex-matched healthy controls. ECGs of 5 patients with congenital DbetaH deficiency and 6 age- and sex-matched controls were also analyzed.

RESULTS

Patients with MSA and PAF had significantly prolonged maximum QTc intervals (492+/-58 ms(1/2) and 502+/-61 ms(1/2) [mean +/- SD]), respectively, compared with controls (450+/-18 ms(1/2), P < .05 and P < .01, respectively). A similar but not significant trend was observed for QT. QTc dispersion was also increased in MSA (40+/-20 ms(1/2), P < .05 vs controls) and PAF patients (32+/-19 ms(1/2), NS) compared with controls (21+/-5 ms(1/2)). In contrast, patients with congenital DbetaH deficiency did not have significantly different RR, QT, QTc intervals, or QTc dispersion when compared with controls.

CONCLUSIONS

Patients with primary autonomic failure who have combined parasympathetic and sympathetic failure have abnormally prolonged QT interval and increased QT dispersion. However, QT interval in patients with congenital DbetaH deficiency was not significantly different from controls. It is possible, therefore, that QT abnormalities in patients with primary autonomic failure are not solely caused by lesions of the sympathetic nervous system, and that the parasympathetic nervous system is likely to have a modulatory role in ventricular repolarization.

Neurohumoral fluid regulation in chronic liver disease

Impaired homeostasis of the blood volume, with increased fluid and sodium retention, is a prevailing element in the deranged systemic and splanchnic haemodynamics in patients with liver disease. In this review, some basic elements of the circulatory changes that take place and of neurohumoral fluid regulation are outlined in order to provide an update of recent investigations on the neuroendocrine compensation of circulatory and volume dysfunction in chronic liver disease. The underlying pathophysiology is a systemic vasodilatation in which newly described potent vasoactive substances such as nitric oxide and vasodilating peptides seem to play an important role. The development of central hypovolaemia and activation of potent vasoconstricting systems such as the renin-angiotensin-aldosterone system and the sympathetic nervous system lead to a hyperdynamic circulation with increased heart rate and cardiac output. Moreover, patients exhibit an autonomic dys- and hyperfunction with vascular hyporeactivity to pressor stimuli. The circulatory dysfunction may be part of a multiorgan failure with disturbed haemodynamics of various vascular beds, including those of the splanchnic system, kidneys, brain and lungs. It is still an enigma why patients with chronic liver disease are at the same time overloaded and functional hypovolaemic with a hyperdynamic, hyporeactive circulation. Further research is needed to find the solution to this apparent haemodynamic conflict concerning the abnormal neurohumoral fluid regulation in chronic liver disease.

Q-T interval prolongation in cirrhosis: prevalence, relationship with severity, and etiology of the disease and possible pathogenetic factors

Prolonged Q-T interval predicts severe arrhythmias and sudden death, and has been shown to occur in alcoholic liver disease and cirrhotic patients who are candidates for liver transplantation. This study first evaluated the prevalence of prolonged Q-T interval in a large population of unselected patients with cirrhosis, and assessed the relationship between abnormal Q-T, etiology, and severity of liver disease and mortality of patients. Possible causes of Q-T abnormality were also explored. Ninety-four patients with cirrhosis without overt heart disease and 37 control subjects with mild chronic active hepatitis were enrolled. Rate-corrected Q-T interval (Q-Tc) was assessed along with routine liver tests, Child-Pugh score, serum bile salts, electrolytes and creatinine, plasma renin activity, aldosterone, norepinephrine, atrial natriuretic factor and, gonadal hormones. Q-Tc was longer in patients with cirrhosis than in controls (440.3 +/- 3.2 vs. 393.6 +/- 3.7 ms; P < .001) and prolonged (> 440 ms) in 44 patients (46.8%) and 2 controls (5.4%; P < .001). Q-Tc length was not influenced by the etiology of cirrhosis and correlated with Child-Pugh score (r = .53; P < .001), liver tests such as prothrombin activity, and serum concentrations of albumin and bilirubin, plasma bile salts, and plasma norepinephrine. Multivariate analysis showed that only Child-Pugh score and plasma norepinephrine were independently correlated with Q-Tc duration. Over a median follow-up period of 19 months (range, 2-33 months), patients with Q-Tc longer than 440 ms had a significantly lower survival rate than those with normal Q-Tc. Q-T interval is frequently prolonged in patients with cirrhosis, regardless the etiology of the disease, worsens in parallel with the severity of the disease, and may have an important prognostic meaning. In addition to other undefined factors related to the severity of cirrhosis, sympathoadrenergic hyperactivity may play a pathogenetic role.