Influence of CYP2D6 and β2-adrenergic receptor gene polymorphisms on the hemodynamic response to propranolol in Chinese Han patients with cirrhosis

Beta-blockers in patients with liver cirrhosis: Pragmatism or perfection?

With increasing decompensation, hyperdynamic circulatory disturbance occurs in liver cirrhosis despite activation of vasoconstrictors. Here, the concept of a therapy with non-selective beta-blockers was established decades ago. They lower elevated portal pressure, protect against variceal hemorrhage, and may also have pleiotropic immunomodulatory effects. Recently, the beneficial effect of carvedilol, which blocks alpha and beta receptors, has been highlighted. Carvedilol leads to "biased-signaling" via recruitment of beta-arrestin. This effect and its consequences have not been sufficiently investigated in patients with liver cirrhosis. Also, a number of questions remain open regarding the expression of beta-receptors and its intracellular signaling and the respective consequences in the intra- and extrahepatic tissue compartments. Despite the undisputed role of non-selective beta-blockers in the treatment of liver cirrhosis, we still can improve the knowledge as to when and how beta-blockers should be used in which patients.

CYP2D6 gene polymorphic markers role in determining the optimal treatment tactics for portal hypertension in patients with liver cirrhosis

Aim. To study the polymorphic markers CYP2D6*4 (G1846A, rs3892097), CYP2D6*6 (T1707del, rs5030655), CYP2D6*10 (C100T, rs1065852), CYP2D6*41 (G2988A, rs28371725) and CYP2D6*3 (A2549del, rs4986774) role in treatment optimization of portal hypertension with propranolol in patients with liver cirrhosis (LC). Materials and methods. The study included 60 patients with LC who received propranolol therapy at a daily dose of 30 mg for 14 days. The efficacy of treatment was assessed by ultrasonography measuring the linear blood flow velocity of portal vein. Genotyping of CYP2D6*4, CYP2D6*6, CYP2D6*10, CYP2D6*41 and CYP2D6*3 was carried out by real-time polymerase chain reaction. Evaluation of the CYP2D6 activity was carried out by determining the ratio of pinoline and its metabolite concentration in morning urine using high performance liquid chromatography with mass spectrometry. Results. Positive hemodynamics in the form of any increase in the mean linear blood flow velocity of the portal vein compared to baseline was observed in 41 patients. Portal vein mean linear blood flow rate increased from 10.43.9 to 14.74.3 cm/s (p0.001). Of these, 29 patients showed an increase in this indicator by 20% from the initial one with a dynamic of 5.5 cm/s (p0.001). The regression analysis constructed by us revealed the presence of a statistically significant effect of the CYP2D6 gene polymorphic marker G1846A carriage on the propranolol therapeutic effect (p0.05). There was no statistically significant effect of polymorphic markers T1707del, C100T, G2988A, and A2549del of the CYP2D6 gene (p0.05). No convincing reliable dependence of CYP2D6 activity on the severity of LC was revealed (p0.05). Conclusion. An association was found between CYP2D6 gene polymorphic marker G1846A carriage and the hemodynamic effect of propranolol in patients with LC of the Russian population. There is a more significant positive dynamics of manifestations of portal hypertension on the background of propranolol therapy in carriers of the homozygous GG CYP2D6*4 genotype, in contrast to patients with the heterozygous GA genotype. Based on the results of the study, an algorithm has been developed for personalizing the treatment of patients with LC with nonselective b-adrenergic blockers using the method of CYP2D6 genotyping. Carriage of polymorphic markers T1707del, C100T, G2988A and A2549del gene CYP2D6 does not affect the effectiveness of propranolol therapy in patients with LC.

Endoscopic therapy + β-blocker vs. covered transjugular intrahepatic portosystemic shunt for prevention of variceal rebleeding in cirrhotic patients with hepatic venous pressure gradient ≥16 mmHg

BACKGROUND AND OBJECTIVE

Currently, monitoring hepatic venous pressure gradient (HVPG) have been proved to be the best predictor for the risk of variceal bleeding. We performed the study to evaluate the effect of endoscopic therapy + β-blocker vs. covered transjugular intrahepatic portosystemic shunt (TIPS) for the prevention of variceal rebleeding in cirrhotic patients with HVPG ≥16 mmHg.

METHODS

Consecutive cirrhotic patients with HVPG ≥16 mmHg treated with endoscopic therapy + β-blocker or covered TIPS for variceal bleeding were retrospectively gathered between April 2013 and December 2018. The variceal rebleeding rate, survival, and incidence of overt hepatic encephalopathy (OHE) were compared.

RESULTS

A total of 83 patients were analyzed, of which 46 received endoscopic therapy + β-blocker and 37 covered TIPS. During a median follow-up of 12.0 months, the rebleeding rate (32.6 vs. 10.8%, P = 0.017) and rate of OHE (2.2 vs. 27.0%, P = 0.001) showed significant differences between the two groups, while liver transplantation-free survival (93.5 vs. 94.6%, P = 0.801) was similar. Preoperative and postoperative Child-Turcotte-Pugh scores were similar in either group. In addition, no significant differences of rebleeding rate (25.0 vs. 21.3%, P = 0.484) and survival (97.2 vs. 91.5%, P = 0.282) were observed between patients with 16 mmHg ≤ HVPG < 20 mmHg and HVPG ≥ 20 mmHg.

CONCLUSION

Covered TIPS was more effective than endoscopic therapy + β-blocker in preventing rebleeding in patients with HVPG ≥16 mmHg but did not improve survival. TIPS also induce more OHE.

Increase in Free Hepatic Venous Pressure Response to Beta-Blockers Predicts Variceal Bleeding in Cirrhotic Patients

Background and Aims

Nonselective beta-blockers (NSBBs) are the main drug to prevent portal hypertension. It could alter free hepatic venous pressure (FHVP); however, the significance is unknown. This prospective study was to explore the change of FHVP after use of NSBBs and its predictive value for gastroesophageal varices (GOV) bleeding in cirrhotic patients. Patients and Methods. Cirrhotic patients with medium-large GOV between September 2014 and January 2019 were enrolled. After initial hepatic venous pressure gradient (HVPG) measurement, patients received oral NSBBs. Seven days later, the secondary HVPG was examined to evaluate the FHVP alteration and hemodynamic response. The variceal bleeding between patients with FHVP increased and decreased/unchanged was compared.

Results

A total of 74 patients were enrolled, and 62 patients completed the secondary HVPG measurement and was followed up. The cumulative bleeding rate was significantly higher in patients with FHVP increased ≥ 1.75 mmHg than those with FHVP decreased/unchanged (54.5% vs. 22.5%, p = 0.021), while there was no significant difference in bleeding between HVPG responders and nonresponders (32.6% vs. 37.5%, p = 0.520). For HVPG responders, variceal bleeding in patients with FHVP increased ≥ 1.75 mmHg was significantly more than that in patients with FHVP decreased/unchanged (57.9% vs. 28.6%, p = 0.041). Cox regression analysis showed that change of FHVP was an independent predictor of variceal bleeding.

Conclusion

Increase ≥ 1.75 mmHg in FHVP responding to beta-blockers in cirrhotic patients with GOV indicates high risk of variceal bleeding. Besides HVPG response, change of FHVP should also be valued in hemodynamic evaluation to beta-blockers. This trial is registered with Chinese Clinical Trial Registry ChiCTR-IPR-17012836.

EUS-guided portal pressure gradient measurement in patients with acute or subacute portal hypertension

BACKGROUND AND AIMS

EUS-guided portal pressure gradient (EUS-PPG) measurement is a novel method to evaluate portal hypertension severity. In this study, we determined the consistency between EUS-PPG and hepatic venous pressure gradient (HVPG) measurements in patients with acute or subacute portal hypertension.

METHODS

Twelve patients were prospectively enrolled. EUS-PPG measurements were performed using a 22-gauge FNA needle and a central venous pressure measurement monitor. The HVPG measurements were performed using the transjugular approach. If an HVPG measurement was not attainable and the patient underwent transjugular intrahepatic portosystemic shunt (TIPS) treatment, a PPG was recorded as a reference standard during the procedure. We assessed the feasibility and safety of EUS-PPG and calculated the correlation between the 2 measurements.

RESULTS

EUS-PPG measurements were successful in 11 patients (91.7%). Subsequent HVPG measurements failed in 2 patients with Budd-Chiari syndrome (hepatic vein occlusion subtype), 1 of whom underwent TIPS treatment to obtain transjugular PPG data. A small shunt was found during 1 HVPG measurement that introduced inaccuracy. Nine patients were included in the statistical analysis. Mean EUS-PPG and HVPG/PPG (transjugular) were 18.07 ± 4.32 mm Hg and 18.82 ± 3.43 mm Hg, respectively. Pearson's correlation coefficient between the 2 methods was .923 (P < .001).

CONCLUSIONS

EUS-PPG measurement using a 22-gauge FNA needle was a safe and accurate method to evaluate portal hypertension and has the potential to supplement the measurement of HVPG in liver diseases. (Clinical trial registration number: ChiCTR1800017317.).

Dose-dependent effect of propranolol on the hemodynamic response in cirrhotic patients with gastroesophageal varices

OBJECTIVE

Propranolol is always titrated to the maximum tolerated dose to prevent gastroesophageal variceal bleeding. However, some patients do not achieve a hemodynamic response and experience more intolerance and discontinuation. This study evaluated the dose-dependent effect of propranolol on hemodynamic response and tolerance in cirrhotic patients.

PATIENTS AND METHODS

This retrospective study included 95 consecutive patients recruited from our prospective database. After hepatic venous pressure gradient measurement, patients received propranolol 10 mg, twice daily increased 10 mg daily until to 80 or 120 mg/day. Secondary hepatic venous pressure gradient was also measured. For nonresponders at 80 mg/day, propranolol was titrated to 120 mg/day.

RESULTS

For 58 patients, propranolol was titrated to 80 mg/day, whereas for 37 patients, it was titrated to 120 mg/day. Hemodynamic response was similar in both groups (50 vs. 54.1%, P=0.700). Eighteen of the 29 nonresponders at propranolol 80 mg/day received a dose of 120 mg/day. Two patients achieved a hemodynamic response, but two could not tolerate the dose. Nine (15.5%) patients achieved the target dose of propranolol at 80 mg/day, whereas 16 (43.2%) patients at 120 mg/day achieved this (P=0.003). The difference in patients achieving the target dose between responders and nonresponders was not significant (14 vs. 14, P=0.642). Reduction or discontinuation was required by two (6.9%) patients using 80 mg/day propranolol and six (30%) patients using 120 mg/day propranolol (P=0.032).

CONCLUSION

There is no dose-dependent effect of 80-120 mg/day of propranolol on the hemodynamic response in cirrhotic patients with gastroesophageal varices. This indicates that low-dose propranolol below the target dose might lead to a considerable hemodynamic response and is much safer and well tolerated.

Pharmacokinetic Parameters and Over-Responsiveness of Iranian Population to Propranolol

Purpose: Propranolol is the most widely used treatment for cardiovascular diseases. Dosage range in our patients is usually less than the amount mentioned in references. The aim of the present study was to clarify whether pharmacokinetic differences are able to justify the need for the fewer doses in our patients or not.

Methods: Twenty healthy volunteers (10 male) at heart center of Mazandaran University of Medical Sciences were studied. Samples of blood were collected before a single oral dose (40 mg) of Propranolol. Blood samples were taken up to 9 hours after dose. Total plasma concentration of Propranolol was measured by HPLC. Population Pharmacokinetic analysis was performed using population pharmacokinetics modeling software P-Pharm.

Results: The mean value for oral plasma clearance (CL/F) was 126.59 ml/hr. The corresponding values for apparent volume of distribution (V/F), t1/2 beta, maximum blood concentration (C max), and time to reach the maximum blood concentration (T max) were 334.12 Lit, 1.98 hr, 40.25 ng/ml, and 1.68 hr, respectively. The observed mean values of V/F of propranolol in the present study were comparable with those reported in the literature. However, the mean values of CL/F of propranolol in current study was significantly higher than those reported in other population (P-value<0.001).

Conclusion: This study has confirmed that the pharmacokinetic differences are not able to justify over-responsiveness of Iranian population to propranolol. Pharmacodynamic differences in responding to beta blocker drugs by Renin secretion or having a different sensibility to beta receptors might play a role in making our population have a different response to propranolol.