Dynamic Changes and Nomogram Prediction for Sinistral Portal Hypertension in Moderate and Severe Acute Pancreatitis

Left-sided portal hypertension: what an interventional radiologist can offer?

Left-sided portal hypertension (LPH) refers to increased splenic venous pressure caused by splenic vein stenosis or occlusion. Pancreatitis is the leading cause of LPH. Typically, LPH remains asymptomatic, but it can lead to life-threatening hemorrhage from ruptured fundal varices in about 10% of patients. Further, it may be complicated by hypersplenism. Interventional radiology plays an essential role in LPH patients with failed endoscopic treatment. Variceal embolization is an effective salvage measure in bleeding gastric varices, but it carries a risk of recurrence and worsening of hypersplenism. Considering the pathophysiology, splenic vein recanalization (SVR) appears to be the best treatment; nevertheless, its lower technical success rate limits its utility only to a subgroup of LPH patients. Partial splenic embolization (PSE), a non-surgical alternative to splenectomy, reduces the splenic volume and venous outflow, thereby lowering variceal pressure. PSE is technically easier, which may explain its widespread use. Nonetheless, PSE can be complicated by life-threatening sepsis and portal vein thrombosis. Despite all attempts, some LPH patients eventually require a splenectomy. Importantly, the choice of therapy requires multidisciplinary discussion and is often influenced by availability, expertise, and clinical context. This article discusses various interventional strategies for managing LPH with the available evidence. KEY POINTS: Question Pressure within the main portal vein is normal in left-sided portal hypertension; thus, transjugular intrahepatic portosystemic shunt is ineffective. Findings Splenic vein stent placement can restore hepatopetal splenic blood flow and decompress splenic venous pressure. Clinical relevance Partial splenic embolization (PSE) is the most widely used interventional approach to manage left-sided portal hypertension-related complications.

Analysis of risk factors and construction of a predictive model for severe acute pancreatitis complicated by sinistral portal hypertension

Objective

Sinistral portal hypertension (SPH) is a common complication of severe acute pancreatitis (SAP). Patients with SPH often present asymptomatic, but are at risk of gastrointestinal bleeding and abdominal bleeding due to the presence of varices of the corresponding vessels, which are often fatal. However, there is no prediction model for SAP combined with SPH. This study aimed to identify the risk factors of SAP combined with SPH and to construct a relevant predictive model using independent risk factors.

Materials and methods

The clinical data of 431 SAP patients were collected in this study. According to the presence or absence of SPH, the patients were divided into SPH group (n = 126) and non-SPH group (n = 305), and 431 patients were randomly assigned to the training set and validation set. Univariate logistics regression analysis was used to screen out the variables with significant differences, and then backward stepwise regression method was used for multivariate logistic regression analysis to determine the independent risk factors of SAP combined with SPH. Then a prediction model was constructed and represented by a nomogram, and the model was verified by internal validation. Receiver operating characteristic (ROC) curve and calibration curve were used to evaluate the predictive ability and accuracy of the model, and decision curve analysis (DCA) was used to evaluate the clinical value of the model.

Results

Multivariate logistic regression analysis showed that male, MCTSI score, white blood cell count (WBC), and portal venous system vascular lesions (PVPSL) were independent risk factors for SAP complicated with SPH. The area under the working curve (AUC) of the clinical nomogram in the training set was 0.95 (95% CI: 0.92-0.97),and the P value of the Hosmer-Lemeshow test of the calibration curve was 0.969. The AUC in the validation set was 0.98 (95%CI: 0.96-1.00), and the P value of the Hosmer-Lemeshow test of the calibration curve was 0.963. The DCA in the training set and the validation set showed good clinical applicability of the model.

Conclusion

Male, MCTSI score, WBC and PVPSL are independent risk factors for SAP complicated with SPH. The establishment of prediction model for SAP complicated with SPH is of great significance for the prevention and treatment of SPH in clinical practice.

Incidence and Management of Splanchnic Vein Thrombosis in Pancreatic Diseases

Splanchnic vein thrombosis (SVT) in pancreatic disease has a 20%-30% incidence rate, leading to increased mortality and complication rates. Therefore, the aim of this review is to summarize recent evidence about the incidence, risk factors, and management of pancreatic cancer, pancreatic cystic neoplasm-, and pancreatitis-related SVT. Doppler ultrasound should be the first imaging choice, followed by contrast-enhanced computed tomography or magnetic resonance imaging. Data regarding SVT treatment in acute pancreatitis and pancreatic cancer are scarce; however, for venous thromboembolism treatment, direct oral anticoagulants and low molecular weight heparin have been effective. Further trials must investigate the length of anticoagulant treatment and the need for interventional radiological procedures.

Assessment of hemodynamic changes in gastric varices using CT findings before and after vascular plug-assisted retrograde transvenous obliteration (PARTO) and evaluation of treatment outcomes

PURPOSE

To assess the treatment outcomes of vascular plug-assisted retrograde transvenous obliteration (PARTO) for gastric varices based on hemodynamic changes observed in pre- and post-procedural CT scans.

METHODS

This single-center study included 43 patients with gastric varices who underwent PARTO between June 2017 and December 2023. Peri-procedural CT and endoscopic findings were retrospectively reviewed to analyze the afferent and draining veins of gastric varices, identify any residual varices or afferent veins after treatment, assess the technical and clinical successes, and determine statistically significant variables associated with clinical success.

RESULTS

In the pre-procedural CT, the most common dominant afferent vein was the posterior gastric vein (81.4%), followed by the short gastric vein (46.5%) and the left gastric vein (37.2%). Post-procedural CT scans were available for 34 patients (34/43), revealing residual varices and afferent veins in 10 patients (10/34). Seven patients had unknown clinical outcomes due to insufficient follow-up data. The technical and clinical success rates were 93.0% (40/43) and 77.8% (28/36), respectively. In the multivariable logistic regression model, the dominant left gastric vein observed in the pre-procedural CT was a significant negative predictor of clinical success (odds ratio, 0.007; P = 0.027). The sum of the diameters of all afferent veins was also a significant negative predictor (odds ratio, 0.708; P = 0.044).

CONCLUSION

A dominant left gastric vein and a larger sum of the diameters of all afferent veins observed in the pre-procedural CT may be associated with an increased risk of clinical failure of PARTO. Therefore, pretherapeutic CT evaluation of the hemodynamics of gastric varices, particularly the type, dominance, and diameter of the afferent veins, could be beneficial for achieving successful PARTO.

Development of a nomogram for predicting pancreatic portal hypertension in patients with acute pancreatitis: a retrospective study

INTRODUCTION

Pancreatic portal hypertension (PPH) is a rare complication of acute pancreatitis (AP) that can lead to severe gastrointestinal bleeding. The risk factors associated with PPH, as well as the overall prognosis, warrant further investigation. This study aims to develop and validate a nomogram to predict PPH in patients with AP.

METHODS

Consecutive patients with AP from 2015 to 2023 were retrospectively included in the study. Demographic data, clinical manifestations within the first week of AP onset, and initial contrast-enhanced CT findings were used to develop the predictive model. Univariate and multivariate Cox regression analyses were performed to identify risk factors for PPH. Based on the results of the multivariate analysis, a nomogram was developed. The patients were randomly divided into training and validation sets at a 7:3 ratio. The accuracy and discriminative power of the predictive model were assessed using the area under the curve (AUC) from the receiver operating characteristic curve and the calibration curve.

RESULTS

Of the 1473 patients with AP, 107 (7.3%) developed PPH within 6 months (range: 2-22 months) during follow-up. Multivariate regression analysis showed that body mass index (BMI) (HR, 1.10; 95% CI 1.04 to 1.16; p=0.001), moderately severe grade (HR, 9.36; 95% CI 4.58 to 19.13; p<0.001), severe grade (HR, 12.95; 95% CI 6.22 to 26.94; p<0.001), diabetes (HR, 2.26; 95% CI 1.47 to 3.47; p<0.001), acute fluid accumulation (HR, 2.13; 95% CI 1.31 to 3.47; p=0.002), and necrosis (HR, 3.64; 95% CI 2.30 to 5.78; p<0.001) were independent risk factors for PPH. A nomogram for predicting PPH was developed, with the predictive curves showing an AUC of 0.859 at 6 months and 0.846 at 9 months. In the validation set, the AUC at both time points was 0.812.

CONCLUSION

In summary, we identified BMI, moderately severe or severe AP, diabetes, acute fluid accumulation, and necrosis as risk factors for AP-related PPH. Using the largest cohort of patients with AP to date, we developed a highly accurate nomogram with strong discriminative ability for predicting PPH. Future studies with larger sample sizes are necessary to confirm our findings and conduct external validation.

Development and validation of a nomogram based on Lasso-Logistic regression for predicting splenomegaly secondary to acute pancreatitis

PURPOSE

Investigate the clinical characteristics of splenomegaly secondary to acute pancreatitis (SSAP) and construct a nomogram prediction model based on Lasso-Logistic regression.

METHODS

A retrospective case-control study was conducted to analyze the laboratory parameters and computed tomography (CT) imaging of acute pancreatitis (AP) patients recruited at Xuanwu Hospital from December 2014 to December 2021. Lasso regression was used to identify risk factors, and a novel nomogram was developed. The performance of the nomogram in discrimination, calibration, and clinical usefulness was evaluated through internal validation.

RESULTS

The prevalence of SSAP was 9.2% (88/950), with the first detection occurring 65(30, 125) days after AP onset. Compared with the control group, the SSAP group exhibited a higher frequency of persistent respiratory failure, persistent renal failure, infected pancreatic necrosis, and severe AP, along with an increased need for surgery and longer hospital stay (P < 0.05 for all). There were 185 and 79 patients in the training and internal validation cohorts, respectively. Variables screened by Lasso regression, including platelet count, white blood cell (WBC) count, local complications, and modified CT severity index (mCTSI), were incorporated into the Logistic model. Multivariate analysis showed that WBC count ≦9.71 × 109/L, platelet count ≦140 × 109/L, mCTSI ≧8, and the presence of local complications were independently associated with the occurrence of SSAP. The area under the receiver operating characteristic curve was 0.790. The Hosmer-Lemeshow test showed that the model had good fitness (P = 0.954). Additionally, the nomogram performed well in the internal validation cohorts.

CONCLUSIONS

SSAP is relatively common, and patients with this condition often have a worse clinical prognosis. Patients with low WBC and platelet counts, high mCTSI, and local complications in the early stages of the illness are at a higher risk for SSAP. A simple nomogram tool can be helpful for early prediction of SSAP.

Clinical Analysis of Sinistral Portal Hypertension

Background

Sinistral portal hypertension (SPH) is the only type of portal hypertension that is entirely curable. However, it can easily cause varicose veins in the esophagus and/or stomach, as well as upper gastrointestinal hemorrhage. This study aimed to investigate the clinical characteristics and treatments of sinistral portal hypertension.

Methods

All patients with pancreatic disease were included in this retrospective cohort study at the Affiliated Hospital of Southwest Medical University (Luzhou, China) from September 2019 to September 2021. The required information including the patient's demographics, serum laboratory indicators, imaging and endoscopy examinations, and clinical features were gathered and evaluated. The results were expressed as numbers and percentages.

Results

Out of the 830 patients with pancreatic diseases, 61 (7.3%) developed SPH. The most common cause of SPH was acute pancreatitis (80.3%), followed by chronic pancreatitis (11.5%). The splenic vein was the most frequently affected vein in patients (45/61, 73.8%). The findings of the contrast-enhanced computed tomography (CECT) indicated that 51 cases (83.6%) had gastric fundal-body varices, and three cases had combined gastric and esophageal varices. In the perigastric collateral channel formation, gastroepiploic varices (43/61, 70.5%) most frequently occurred in patients with SPH. Splenomegaly was a prevalent manifestation in SPH patients (45.9%). Five cases had gastrointestinal variceal hemorrhage.

Conclusion

SPH was associated with the patency of the splenic vein and the formation of distinctive perigastric collateral veins. Surgery and/or endoscopic treatment were recommended, particularly for patients who have experienced a significant amount of gastrointestinal bleeding and have failed conservative treatment.

Etiologies of Splenic Venous Hypertension: A Review

Splenic venous hypertension or left-sided portal hypertension is a rare condition caused by an obstruction of the splenic vein. Usually, it presents with upper gastrointestinal bleeding in the absence of liver disease. Etiologies can be classified based on the mechanism of development of splenic vein hypertension: compression, stenosis, inflammation, thrombosis, and surgically decreased splenic venous flow. Diagnosis is established by various imaging modalities and should be suspected in patients with gastric varices in the absence of esophageal varices, splenomegaly, or cirrhosis. The management and prognosis vary depending on the underlying etiology but generally involve reducing splenic venous pressure. The aim of this review was to summarize the etiologies of splenic venous hypertension according to the mechanism of development.

Analysis of risk factors for acute pancreatitis complicated with pancreatic sinistral portal hypertension and construction of predictive model

Objective: Pancreatic sinistral portal hypertension (PSPH) is a common complication of acute pancreatitis (AP) and can cause massive gastrointestinal bleeding, which is one of the causes of AP-related mortality. However, there is currently no predictive model for AP concurrent with PSPH. This study aimed to identify the risk factors for AP concurrent with PSPH and use these factors to build a related predictive model. Materials and methods: We collected clinical data from 282 patients with AP. 192 patients were used as a training group and 90 patients as a validation group. Univariate and multivariate analyses were used to identify independent risk factors for AP complicated with PSPH, and then a nomogram was established. The models are cross verification and Internal verification. The predictive ability and accuracy of the model were evaluated based on the working curve of the subjects and the calibration curve, respectively. The clinical value of the model was evaluated using decision curve analysis (DCA). Results: The univariate analysis revealed significant differences in the occurrence of PSPH with respect to sex, recurrent AP, history of hypertension, smoking history, patency of the splenic vein, pancreatic necrosis or pancreatic pseudocyst formation, the most significant site of pancreatic swelling, presence of a Dmure D polymer, MCTSI, and involvement of lipase and amylase. The logistic multivariate regression analysis showed that male sex, splenic-vein stenosis or occlusion and swelling were located in the body-tail, and MCTSI was an independent risk factor for PSPH. The nomogram and ROC curve were constructed. The area under the working curve of the subjects was 0.91, and the sensitivity and specificity were 82.5% and 89.1%, respectively. In the validation group, the C-index is 0.826. The nomogram was internally validated using 1,000 bootstrap samples, and the c-index was 0.898. The calibration curve demonstrated that the predicted probability was concordant with the observed probability, and the DCA confirmed that the model had robust clinical utility. Conclusion: Male sex, splenic-vein stenosis or occlusion, recurrent AP, and swelling are located in the body-tail, and MCTSI is an independent risk factor for the occurrence of PSPH. The predictive model developed for AP complicated with PSPH may serve toward developing preventive and therapeutic approaches for PSPH.

Sinistral Portal Hypertension Due to a Pancreatic Pseudocyst: A Rare Cause of Upper Gastrointestinal Bleeding

Sinistral portal hypertension (SPH), also known as segmental portal hypertension, is a complication of pancreatic disorders and an extremely rare cause of upper gastrointestinal (GI) bleeding. SPH is observed in patients without cirrhosis and arises from splenic vein thrombosis. Unmitigated backflow of blood may cause gastric venous congestion and ultimately GI hemorrhage. Herein, we report a rare case of massive hematemesis due to SPH in a male patient with a history of chronic pancreatitis and pancreatic pseudocyst. Our patient was successfully treated with endoscopic necrosectomy followed by open splenectomy, distal pancreatectomy, and partial gastric resection.

A narrative review of acute pancreatitis-induced splanchnic vein thrombosis: from pathogenesis to clinical management

Acute pancreatitis-induced splanchnic vein thrombosis (APISVT) is an important sequela complication of acute pancreatitis, which may cause poor prognosis, such as severe gastrointestinal hemorrhage, bowel ischemic necrosis and liver failure. However, its mechanism remains uncertain, and there is not a general consensus on the management. In this study, we reviewed the latest academic publications in APISVT, and discussed its pathogenesis, clinical presentation, adverse outcome and treatment, especially focused on the role of anticoagulant therapy. It was indicated that anticoagulation therapy can significantly elevate thrombus recanalization and reduce the incidence of complications and mortality with no increase of bleeding. Actually, as most of these studies were retrospective analyses and prospective studies included small samples, the conclusion remains controversial. Thus, well-designed randomized controlled trials are urged to verify the effectiveness and safety of anticoagulation therapy for APISVT.