Liver fibrosis as a predictor of liver failure and outcome following ALPPS among patients with primary liver cancer.

The influence of liver fibrosis on the rate of liver regeneration and complications following ALPPS has yet to be fully understood. This study aimed to scrutinize the effects of liver fibrosis on the postoperative complications, and prognosis subsequent to ALPPS. Clinical data were collected from patients with primary liver cancer who underwent ALPPS at Peking Union Medical College Hospital between May 2014 and October 2022. The degree of liver fibrosis was assessed using haematoxylin-eosin staining and Sirius red staining. This study encompassed thirty patients who underwent ALPPS for primary liver cancer, and there were 23 patients with hepatocellular carcinoma, 5 with cholangiocarcinoma, and 2 with combined hepatocellular-cholangiocarcinoma. The impact of severe liver fibrosis on the rate of liver regeneration was not statistically significant (P = 0.892). All patients with severe complications belonged to the severe liver fibrosis group. Severe liver fibrosis exhibited a significant association with 90 days mortality (P = 0.014) and overall survival (P = 0.012). Severe liver fibrosis emerges as a crucial risk factor for liver failure and perioperative mortality following the second step of ALPPS. Preoperative liver function impairment is an important predictive factor for postoperative liver failure.

Characterisation of LPS+ bacterial extracellular vesicles along the gut-hepatic portal vein-liver axis.

Gut microbiome dysbiosis is a major contributing factor to several pathological conditions. However, the mechanistic understanding of the communication between gut microbiota and extra-intestinal organs remains largely elusive. Extracellular vesicles (EVs), secreted by almost every form of life, including bacteria, could play a critical role in this inter-kingdom crosstalk and are the focus of present study. Here, we present a novel approach for isolating lipopolysaccharide (LPS)+ bacterial extracellular vesicles (bEVLPS) from complex biological samples, including faeces, plasma and the liver from lean and diet-induced obese (DIO) mice. bEVLPS were extensively characterised using nanoparticle tracking analyses, immunogold labelling coupled with transmission electron microscopy, flow cytometry, super-resolution microscopy and 16S sequencing. In liver tissues, the protein expressions of TLR4 and a few macrophage-specific biomarkers were assessed by immunohistochemistry, and the gene expressions of inflammation-related cytokines and their receptors (n = 89 genes) were measured using a PCR array. Faecal samples from DIO mice revealed a remarkably lower concentration of total EVs but a significantly higher percentage of LPS+ EVs. Interestingly, DIO faecal bEVLPS showed a higher abundance of Proteobacteria by 16S sequencing. Importantly, in DIO mice, a higher number of total EVs and bEVLPS consistently entered the hepatic portal vein and subsequently reached the liver, associated with increased expression of TLR4, macrophage markers (F4/80, CD86 and CD206), cytokines and receptors (Il1rn, Ccr1, Cxcl10, Il2rg and Ccr2). Furthermore, a portion of bEVLPS escaped liver and entered the peripheral circulation. In conclusion, bEV could be the key mediator orchestrating various well-established biological effects induced by gut bacteria on distant organs.

Clinical features and prediction of long-term survival after surgery for perihilar cholangiocarcinoma.

INTRODUCTION: The treatment of perihilar Cholangiocarcinoma (pCCA) poses specific challenges not only due to its high perioperative complication rates but also due its dismal long-term prognosis with only a few long-term survivors (LTS) among the patients. Therefore, in this analysis characteristics and predictors of LTS in pCCA patients are investigated. MATERIAL AND METHODS: In this single center analysis, patients undergoing curative-intent liver resection for pCCA between 2010 and 2022 were categorized into long-term and short-term survivors (STS) excluding perioperative mortality. Binary logistic regression was used to determine key differences between the groups and to develop a prognostic composite variable. This composite variable was subsequently tested in the whole cohort of surgically treated pCCA patients using Cox Regression analysis for cancer-specific survival (CSS). RESULTS: Within a cohort of 209 individuals, 27 patients were identified as LTS (median CSS = 125 months) and 55 patients as STS (median CSS = 16 months). Multivariable analysis identified preoperative portal vein infiltration (OR = 5.85, p = 0.018) and intraoperative packed red blood cell (PRBC) transfusions (OR = 10.29, p = 0.002) as key differences between the groups. A prognostic composite variable based on these two features was created and transferred into a Cox regression model of the whole cohort. Here, the composite variable (HR = 0.35, p<0.001), lymph node metastases (HR = 2.15, p = 0.001) and postoperative complications (HR = 3.06, p<0.001) were identified as independent predictors of CSS. CONCLUSION: Long-term survival after surgery for pCCA is possible and is strongly negatively associated with preoperative portal vein infiltration and intraoperative PRBC transfusion. As these variables are part of preoperative staging or can be modulated by intraoperative technique, the proposed prognostic composite variable can easily be transferred into clinical management to predict the oncological outcome of patients undergoing surgery for pCCA.

Analysis of factors related to recanalization of portal vein thrombosis in liver cirrhosis: a retrospective cohort study.

BACKGROUND: Portal vein thrombosis (PVT) is a common complication of liver cirrhosis, yet there are fewer studies about predictors of PVT recanalization. We aimed to further explore the predictors of recanalization in cirrhotic PVT to facilitate accurate prediction of patients' clinical status and timely initiation of appropriate treatment and interventions. To further investigate the benefits and risks of anticoagulant therapy in cirrhotic PVT patients. METHODS: A retrospective cohort study of patients with cirrhotic PVT in our hospital between January 2016 and December 2022, The primary endpoint was to analyze predictors of PVT recanalization by COX regression. Others included bleeding rate, liver function, and mortality. RESULTS: This study included a total of 82 patients, with 30 in the recanalization group and 52 in the non-recanalization group. Anticoagulation therapy was the only independent protective factor for portal vein thrombosis recanalization and the independent risk factors included massive ascites, history of splenectomy, Child-Pugh B/C class, and main trunk width of the portal vein. Anticoagulation therapy was associated with a significantly higher rate of PVT recanalization (75.9% vs. 20%, log-rank P < 0.001) and a lower rate of PVT progression (6.9% vs. 54.7%, log-rank P = 0.002). There was no significant difference between different anticoagulation regimens for PVT recanalization. Anticoagulation therapy did not increase the incidence of bleeding complications(P = 0.407). At the end of the study follow-up, Child-Pugh classification, MELD score, and albumin level were better in the anticoagulation group than in the non-anticoagulation group. There was no significant difference in 2-year survival between the two groups. CONCLUSION: Anticoagulation, massive ascites, history of splenectomy, Child-Pugh B/C class, and main portal vein width were associated with portal vein thrombosis recanalization. Anticoagulation may increase the rate of PVT recanalization and decrease the rate of PVT progression without increasing the rate of bleeding. Anticoagulation may be beneficial in improving liver function in patients with PVT in cirrhosis.

Classification of variant portal vein anatomy based on three-dimensional CT: surgical implications.

PURPOSES: The purpose of this study was to develop a new and more comprehensive classification system for portal vein (PV) variations using three-dimensional visualization and evaluation (3DVE) and to discuss the prevalence rates and clinical implications of the variants. METHODS: The anatomies of PVs were tracked and analyzed by using three-dimensional visualization of CT images acquired between 2013 and 2022. Scans from 200 adults were evaluated and a total of 178 patients (N = 178) were included in the study. The new classification system, named BLB classification, was developed based on the level of the absent PV branch in each variant anatomy. RESULTS: Using the BLB classification system, PVs were divided into thirteen subtypes. Only 82.6-84.8% of the portal veins of the 178 patients were depicted in Atri's, Cheng's or Covey's classification, compared with 100% identified by the BLB classification. The BLB classification was validated against external data sets from previous studies, with 97.0-98.9% of patients classified by the BLB system. CONCLUSION: Variant PV anatomies are more commonly seen based on 3DVE than in previous reports. The BLB classification covers almost all portal vein variants and may be used for planning liver surgery.

Cell atlas of the regenerating human liver after portal vein embolization.

The liver has the remarkable capacity to regenerate. In the clinic, regeneration is induced by portal vein embolization, which redirects portal blood flow, resulting in liver hypertrophy in locations with increased blood supply, and atrophy of embolized segments. Here, we apply single-cell and single-nucleus transcriptomics on healthy, hypertrophied, and atrophied patient-derived liver samples to explore cell states in the regenerating liver. Our data unveils pervasive upregulation of genes associated with developmental processes, cellular adhesion, and inflammation in post-portal vein embolization liver, disrupted portal-central hepatocyte zonation, and altered cell subtype composition of endothelial and immune cells. Interlineage crosstalk analysis reveals mesenchymal cells as an interaction hub between immune and endothelial cells, and highlights the importance of extracellular matrix proteins in liver regeneration. Moreover, we establish tissue-scale iterative indirect immunofluorescence imaging for high-dimensional spatial analysis of perivascular microenvironments, uncovering changes to tissue architecture in regenerating liver lobules. Altogether, our data is a rich resource revealing cellular and histological changes in human liver regeneration.

Enhancement of endothelial function and attenuation of portal vein injury using mesenchymal stem cells carrying miRNA-25-3p.

The aims of this study were to determine whether human umbilical cord mesenchymal stem cells (hucMSCs) modified by miRNA-25-3p (miR-25-3p) overexpression could promote venous endothelial cell proliferation and attenuate portal endothelial cell injury. HucMSCs and human umbilical vein endothelial cells (HUVEC) were isolated and cultured from human umbilical cord and characterized. Lentiviral vectors expressing miRNA-25-3p were transfected into hucMSCs and confirmed by PCR. We verified the effect of miR-25-3p-modified hucMSCs on HUVEC by cell co-culture and cell supernatant experiments. Subsequently, exosomes of miR-25-3p-modified hucMSCs were isolated from cell culture supernatants and characterized by WB, NTA and TEM. We verified the effects of miR-25-3p-modified exosomes derived from hucMSCs on HUVEC proliferation, migration, and angiogenesis by in vitro cellular function experiments. Meanwhile, we further examined the downstream target genes and signaling pathways potentially affected by miR-25-3p-modified hucMSC-derived exosomes in HUVEC. Finally, we established a rat portal vein venous thrombosis model by injecting CM-DiR-labeled hucMSCs intravenously into rats and examining the homing of cells in the portal vein by fluorescence microscopy. Histological and immunohistochemical experiments were used to examine the effects of miRNA-25-3p-modified hucMSCs on the proliferation and damage of portal vein endothelial cells. Primary hucMSCs and HUVECs were successfully isolated, cultured and characterized. Primary hucMSCs were modified with a lentiviral vector carrying miR-25-3p at MOI 80. Co-culture and cell supernatant intervention experiments showed that overexpression of miRNA-25-3p in hucMSCs enhanced HUVEC proliferation, migration and tube formation in vitro. We successfully isolated and characterized exosomes of miR-25-3p-modified hucMSCs, and exosome intervention experiments demonstrated that miR-25-3p-modified exosomes derived from hucMSCs similarly enhanced the proliferation, migration, and angiogenesis of HUVECs. Subsequent PCR and WB analyses indicated PTEN/KLF4/AKT/ERK1/2 as potential pathways of action. Analysis in a rat portal vein thrombosis model showed that miR-25-3p-modified hucMSCs could homing to damaged portal veins. Subsequent histological and immunohistochemical examinations demonstrated that intervention with miR-25-3p overexpression-modified hucMSCs significantly reduced damage and attenuated thrombosis in rat portal veins. The above findings indicate suggest that hucMSCs based on miR-25-3p modification may be a promising therapeutic approach for use in venous thrombotic diseases.

Sequential Blood Collection from Inferior Vena Cava Followed by Portal Vein to Evaluate Gut Microbial Metabolites in Mice.

Gut microbial products are known to act both locally within the intestine and get absorbed into circulation, where their effects can extend to numerous distant organ systems. Short-chain fatty acids (SCFA) are one class of metabolites produced by gut microbes during the fermentation of indigestible dietary fiber. They are now recognized as important contributors to how the gut microbiome influences extra-intestinal organ systems via the gut-lung, gut-brain, and other gut-organ axes throughout the host. SCFAs are absorbed from the colon, through intestinal tissue, into the portal vein (PV). They then pass through the liver, and are consumed in various organs such as the brain, muscle, adipose tissue, and lungs. SCFAs are most easily measured in the expelled fecal material however, more accurate measurements have been obtained from intra-colonic fecal contents. Here we propose that sampling PV and systemic circulating plasma of a single subject may be preferable for studying the absorption, transport, and systemic levels of SCFAs in mice. We present a new technique for efficient blood sampling from the PV and inferior vena cava (IVC) that allows for the collection of relatively large volumes of blood from the portal and systemic circulations. This is accomplished by ligating the PV, thereby allowing for the dilation or enlargement of the PV as it backfills from the mesenteric veins that drain into it. Using this method, we were able to improve the rate of successful collection as well as the total amount of blood collected (up to 0.3 mL from IVC and 0.5 mL from PV).

Portal vein thrombosis associated with acute cholecystitis.

ABSTRACT: Portal venous thrombosis (PVT) is an uncommon clinical problem and is rare following cholecystectomy. This article describes a patient who developed PVT after an initially uneventful laparoscopic cholecystectomy. The patient was successfully treated with IV antibiotics and anticoagulation.

[New targets for the prevention and treatment of cirrhotic portal vein thrombosis].

Portal vein thrombosis (PVT) is divided into cirrhotic and non-cirrhotic PVTs. The incidence rate of PVT varies greatly among different clinical stages of cirrhosis, with an overall incidence rate of about 13.92%, and the prevalence of cirrhotic PVT following splenectomy is as high as 60%. The pathogenesis of cirrhotic PVT is still unclear. However, the activation of Janus kinase/signal transduction and activator transcription signaling pathways, the rise in the expression of von Willebrand factor, and the gut microbiota along with its metabolite trimethylamine-N-oxide play an important role in the injury of vascular endothelial cells and the formation of PVT in cirrhosis. Therefore, these could be a new target for cirrhotic PVT prevention and treatment.

[Porto sinusoidal vascular disease: an unusual cause of digestive bleeding]. / Enfermedad vascular porto sinusoidal: una causa inusual de sangrado digestivo.

Portal hypertension (PHT) is defined as an increase in pressure at the level of the portal vein above 5 mmHg, the most common cause being liver cirrhosis. Among the presinusoidal intrahepatic causes of PHT with portal venular involvement, what was traditionally known as idiopathic non-cirrhotic portal hypertension (NCIH) is described, with the requirements of excluding those patients who did not present PHT, as well as those with the presence of liver cirrhosis and thrombosis. portal venous vein (PVT). Currently, the diagnostic criteria for this entity have been reconsidered, and its name, being known as porto-sinusoidal vascular disease (PSVD), also does not exclude patients with PHT or the presence of underlying liver disease. Liver biopsy continues to be the gold standard for diagnosis. The clinical manifestations are derived from PHT and the management is similar to the complications that occur in patients with liver cirrhosis. The case of a male patient is presented who presents with symptoms of digestive bleeding, with findings of esophageal varices in upper endoscopy in addition to a study of viral, autoimmune liver disease and negative deposits, with a conclusive liver biopsy of porto-sinusoidal vascular disease.

The Significance of Congenital Portosystemic Shunts in Congenital Heart Disease and the Bizarre Phenomenon of Alternating Portosystemic and Systemic-Portal Shunting.

Congenital portosystemic shunts (CPSSs) are rare vascular anomalies characterized by abnormal connections between the portal/splanchnic veins and the systemic veins. CPSSs often occur as an isolated congenital anomaly, but they can also coexist with congenital heart disease (CHD). Owing to their myriad consequences on multiple organ systems, familiarity with CPSS is of tremendous importance to the care of patients with CHD. The rationale and timing for interventions to embolize CPSS in this scenario are discussed. Specific shunt embolization techniques are beyond the scope of this article.

Hepatic Encephalopathy Secondary to Non-cirrhotic Portosystemic Shunt.

Hepatic encephalopathy is uncommon in the absence of cirrhosis. We report a 71-year-old woman who presented with altered mental status in the setting of hyperammonemia for the second time in 6 months. Magnetic resonance imaging of the abdomen revealed an uncommon portosystemic shunt involving an enlarged posterior branch of the right portal vein and an accessory right hepatic vein, with no features of cirrhosis. Appropriate management of these patients with ammonia-lowering therapy can reduce repeat episodes and improve quality of life. This case demonstrates the importance of diagnosing non-cirrhotic hepatic encephalopathy in patients with altered mental status.

Computed tomographic evaluation of portal vein indices in cats with the extrahepatic portosystemic shunts.

IMPORTANCE: The portal vein to aorta (PV/Ao) ratio is used to assess the clinical significance of extrahepatic portosystemic shunt (EHPSS). Previous studies using computed tomography (CT) were conducted in dogs but not in cats. OBJECTIVE: This study aimed to establish normal reference values for PV indices (PV/Ao ratio and PV diameter) in cats and determine the usefulness of these for predicting symptomatic EHPSS. METHODS: This study included 95 dogs and 114 cats that underwent abdominal CT. The canine normal (CN) group included dogs without EHPSS. The cats were classified into feline normal (FN, 88/114), feline asymptomatic (FA, 16/114), and feline symptomatic (FS, 10/114) groups. The PV and Ao diameters were measured in axial cross-sections. RESULTS: The group FN had a higher PV/Ao ratio than the group CN (p < 0.001). Within the feline groups, the PV indices were in the order FN > FA > FS (both p < 0.001). The mean PV diameter and PV/Ao ratio for group FN were 5.23 ± 0.77 mm and 1.46 ± 0.19, respectively. The cutoff values between groups FN and FS were 4.115 mm for PV diameter (sensitivity, 100%; specificity, 97.7%) and 1.170 for PV/Ao ratio (90%, 92.1%). The cutoff values between group FA and FS were 3.835 mm (90%, 93.8%) and 1.010 (70%, 100%), respectively. CONCLUSIONS AND RELEVANCE: The results demonstrated significant differences in PV indices between dogs and cats. In cats, the PV/Ao ratio demonstrated high diagnostic performance for symptomatic EHPSS. The PV diameter also performed well, in contrast to dogs.

Living donor liver transplantation for patients with portal vein thrombosis: high-volume single center experience.

OBJECTIVE: End-stage liver disease is commonly associated with portal vein thrombosis (PVT). Lastly, PVT is no longer an absolute contraindication for liver transplantation, and many centers adopt portal vein thrombectomy. PVT imposes special technical difficulties during living donor liver transplantation (LDLT). In this research, the experience with PVT cases during LDLT in a high-volume center is introduced. PATIENTS AND METHODS: Between January 2018 and July 2023, 312 patients underwent LDLT. After 88 cases were excluded, 224 cases were included, and their incidence of pre-transplant PVT was 16.5% (37/224). Demographic and clinical features, perioperative variables, and post-transplant outcomes of patients with PVT (PVT group, n=37) were compared to patients who had no PVT (non-PVT group, n=187). RESULTS: According to Yerdel classification, 16, 16, 2, and 3 patients had PVT grade I, II, III, and IV, respectively. Complete venous thrombectomy was accomplished in 34 patients, while for three patients, thrombectomy was not feasible, and graft inflow was established by interposition vascular graft. For portal flow modulation, splenectomy and splenic artery ligation were performed in 7 and 4 patients, respectively, while two patients underwent post-transplant splenic artery embolization. The PVT group had longer operation time (p<0.001), longer warm ischemia time (p=0.031), longer anhepatic phase (p<0.001), and intraoperatively required more than 3 packed RBCs units (p=0.029) and ≥1 platelet unit transfusion (p=0.021) than the non-PVT group. No statistically significant difference was found between groups in terms of re-exploration (p=0.954), post-transplant PVT (p=0.375), biliary (p=0.253) and arterial complications (p=0.593), ICU stay (p=0.633), hospital stay (p=896), and 30-day mortality (p=1.000). Survival analysis showed no statistically significant difference regarding 1-year survival (p=0.176) between both groups. CONCLUSIONS: This study showed that patients with different stages of PVT can successfully undergo LDLT in experienced centers and that they do not differ from patients without PVT in terms of post-transplant complications.

Portal Vein Doppler Is a Sensitive Marker for Evaluating Venous Congestion in End-Stage Kidney Disease.

INTRODUCTION: Determining ultrafiltration volume in patients undergoing intermittent hemodialysis (IHD) is an essential component in the assessment and management of volume status. Venous excess ultrasound (VExUS) is a novel tool used to quantify the severity of venous congestion at the bedside. Given the high prevalence of pulmonary hypertension in patients with end-stage kidney disease (ESKD), venous Doppler could represent a useful tool to monitor decongestion in these patients. METHODS: This is a prospective observational study conducted in ESKD patients who were admitted to the hospital requiring IHD and ultrafiltration. Inferior vena cava maximum diameter (IVCd), portal vein Doppler (PVD), and hepatic vein Doppler (HVD) were performed in all patients before and after a single IHD session. RESULTS: Forty-one patients were included. The prevalence of venous congestion was 88% based on IVCd and 63% based on portal vein pulsatility fraction (PVPF). Both mean IVCd and PVPF displayed a significant improvement after ultrafiltration. The percent decrease in PVPF was significantly larger than the percent decrease in IVCd. HVD alterations did not significantly improve after ultrafiltration. CONCLUSIONS: Our study revealed a high prevalence of venous congestion in hospitalized ESKD patients undergoing hemodialysis. After a single IHD session, there was a significant improvement in both IVCd and PVPF. HVD showed no significant improvement with one IHD session. PVPF changes were more sensitive than IVCd changes during volume removal. This study suggests that, due to its rapid response to volume removal, PVD, among the various components of the VExUS grading system, could be more effective in monitoring real-time decongestion in patients undergoing IHD.

Microarray analysis demonstrates up-regulation of the endothelin-1 gene with compensatory down-regulation of the ETA receptor gene in human portal vein.

High blood pressure in the portal vein, portal hypertension (PH), is the final common pathway in liver cirrhosis regardless of aetiology. Complications from PH are the major cause of morbidity and mortality in these patients. Current drug therapy to reduce portal pressure is mainly limited to ß-adrenergic receptor blockade but approximately 40% of patients do not respond. Our aim was to use microarray to measure the expression of ∼20,800 genes in portal vein from patients with PH undergoing transplantation for liver cirrhosis (PH, n=12) versus healthy vessels (control, n=9) to identify potential drug targets to improve therapy. Expression of 9,964 genes above background was detected in portal vein samples. Comparing PH veins versus control (adjusted P-value < 0.05, fold change > 1.5) identified 548 up-regulated genes and 1,996 down-regulated genes. The 2,544 differentially expressed genes were subjected to pathway analysis. We identified 49 significantly enriched pathways. The endothelin pathway was ranked the tenth most significant, the only vasoconstrictive pathway to be identified. ET-1 gene (EDN1) was significantly up-regulated, consistent with elevated levels of ET-1 peptide previously measured in PH and cirrhosis. ETA receptor gene (EDNRA) was significantly down-regulated, consistent with an adaptive response to increased peptide levels in the portal vein but there was no change in the ETB gene (EDNRB). The results provide further support for evaluating the efficacy of ETA receptor antagonists as a potential therapy in addition to ß-blockers in patients with PH and cirrhosis.

Similar Efficacy Between Atezolizumab Plus Bevacizumab Versus Hepatic Arterial Infusion Chemotherapy For Unresectable Hepatocellular Carcinoma With Portal Vein Tumor Thrombus: A Retrospective Cohort Study.

BACKGROUND/AIM: The landscape of treatments for hepatocellular carcinoma (HCC), including immune checkpoint inhibitors, has expanded significantly. However, unresectable HCC patients with portal vein tumor thrombus (PVTT) continue to face a poor prognosis. This investigation examined the survival outcomes and determinants influencing survival rates in advanced HCC patients with PVTT undergoing treatment with atezolizumab plus bevacizumab (ATZ+BEV) or hepatic arterial infusion chemotherapy (HAIC). PATIENTS AND METHODS: Between December 2003 and June 2023, 48 advanced HCC with PVTT underwent treatment with either ATZ+BEV (16 patients) or HAIC (32 patients). RESULTS: The analysis revealed no significant disparities in overall survival (OS) or treatment efficacy between the ATZ+BEV and HAIC groups (ATZ+BEV: 10.0 months, HAIC: 15.3 months). Treatment with either ATZ+BEV or HAIC resulted in minimal alterations in the ALBI score and preserved hepatic function. Independent prognostic factors for OS, identified via multivariate logistic regression, included serum α-fetoprotein levels >400 ng/ml [hazard ratio (HR)=1.94; p=0.001], the existence of more than five tumors (HR=1.55; p=0.043), and the Child-Pugh score (HR=2.53; p=0.002). CONCLUSION: This investigation revealed no significant variance in OS and response rates between patients receiving ATZ+BEV and those treated with HAIC. The survival of advanced HCC patients with PVTT is intricately linked to the preservation of liver function, emphasizing the necessity for additional research to enhance treatment approaches for this patient population.