The Study On Clinical Presentation Of Ischemic Bowel Disease And CT Imaging Of Intestinal Vascular Lesion

Background: The incidence of ischemic bowel disease (ICBD) is increasing alongwith growing aging population and frequently occurred atherosclerosis diseases. Themortality of acute mesenteric ischemia (AMI) is50-90%despite of recent advances indiagnosis and treatment. Frequent abdominal pain caused by chronic mesentericischemia (CMI) badgers the elder with sever atherosclerosis. While delayed treatment ofischemic colitis (IC, a condition most commonly caused by hypotension and instabilityof splanchnic circulation) is often dangerous and linked with bad prognosis. Therefore,deepening the understanding of ICBD pathogenesis and identifying the risk factorsassociated with death were important for effective secondary prevention, reducing theincidence, as well as improving prognosis of ICBD.Objectives:1. To investigate clinical characteristics, CT imaging and risk factorsrelated to death in ICBD,2. To elucidate vascular basis lesion of acute superiormesenteric artery thrombosis embolism (ASMATE) in CT imaging,3. To Providehelpful evidence for comprehensive profound understanding of ICBD.Methods:1. Patients with ICBD patients were enrolled in the retrospective analysis fromJanuary2000to December2013in the PLA General Hospital. Data on clinicalcharacteristic, laboratory parameters, complications, medications and outcomes werecollected.2. CT imaging data in ICBD patients who were admitted after2008and received CTscanning in the PLA General Hospital were reviewed, in order to find CT imagingfeatures in intestinal lesions associated with ICBD death. 3. We utilized The Agatston calcium scores to evaluate calcium scores of Superiormesenteric artery (SMA) and adjacent6cm abdomen aorta. and described intimatelyshapes and distribution characteristics of calcification plaque. The volume software wasused to calculate volume non-calcification plaque, and intestinal artery atherosclerosiscourse was understood through calcification plaque and non-calcification plaque.ResultsAll patients (mean age:61±17years) included223males (72.17%) and86females(27.83%). There were189patients with AMI,13patints with CMI, and107patientswith IC. The AMI patients included79patients with ASMATE,96patients with Acutesuperior mesenteric venous thrombosis (ASMVT)，14patients with nonocclusivemesenteric ischemia(NOMI).1. Clinical characteristics of189patients with AMI:(1) Clinical characteristics of79patients with ASMATE:The patients were classified into the survival group (n=50) and the death group(n=29) according to the prognosis. The average age was63years old and the ratio ofmale/female was2.04:1. Compared with the death group, the survival group had moreweight loss(P=0.034), lower incidence of peritoneal signs and hypotension(P=0.001，P=0.006), lower blood cell and neutrophilic leukocyte percentage (P=0.006，P=0.006),lower incidence of decreased haematoglobin (P=0.007).In the survival group, the elapsed time between the symptoms onset and treatmentwas shorter (P=0.003); the average length of intestinal resection was shorter (P=0.023);less patients received second bowel resection(P=0.007); lower incidence of ascites orbloody ascites, and less patients with ascites exceeding1000ml (P <0.05). In the deathgroup, more patients received laparotomy than interventional therapy(P=0.007). For the51patients underwent intestinal resection, patients who received intestine resection andcolectomy had higher WBC count (P=0.046) and higher mortility than those withintestinal resection only (P<0.001).The patients were classified into the thrombosis group (n=41) and the embolismgroup (n=38) according to the etiology. Compared with embolic occlusion patients group, the thrombotic occlusion group had more patients receiving intestine resectionand colectomy, higher incidence of peripheral artery atherosclerotic diseases(P=0.011,P=0.044), and less patients having atrial fibrillation and peripheral artery embolism (P<0.001, P=0.043).(2) Clinical characteristics of96patients with ASMVT:The patients were divided into the survival group (n=83) and the death group (n=13)according to the prognosis. The average age was46years old and the ratio ofmale/female was3:1.39Patients presented isolated mesenteric venous thrombus (MVT)and57patients presented combined MVT. The death group had higher incidence ofsevere acute pancreatitis and isolated MVT than the survival group(P <0.01, P=0.004).The shorter interval between symptoms onset and treatment, the higher incidence ofisolated MVT and higher mortality were found in the laparotomy group. There was nodeath in the conservative treated group.In comparison with the combined MVT group, the isolated MVT group had morepatients with peritoneal signs and those with history of splenectomy(P<0.001, P=0.002).Patients with laparotomy and bowel necrosis in the isolated MVT group were more thanthose in the combined MVT group(P=0.023, P=0.012).(3) Clinical characteristics of14patients with NOMI:The patients were divided into the survival group (n=10) and the death group (n=4)according to the prognosis. The average age was66years old and the ratio ofmale/female was1.33:1. The average age of the survival group was younger than thedeath group(P=0.004). Less patients had taken NSAIDS in the survival group than inthe death group(P=0.011).Nine patients received surgical treatment and five patients conservative treatment.Eight patients underwent bowel resection surgery, including three patients withintestinal ischemia, four with extensive bowel ischemia, and one with colon ischemia.All patients with extensive bowel ischemic died(P=0.002).2. Clinical characteristics of13patients with CMI:The average age of this group was66years old and the ratio of male/female was 2.25:1. All patients had at least one atherosclerosis disease. There were11patientsundertaking endoscopy test. Of these, four patients with peptic ulcers were negative inHP C13-UBT, two of which were placed SMA and CA stents, and others were placedonly SMA stents.All patients had SMA lesions, and patients with moderate to sever stenosis in SMAwere more than those in CA and IMA. Of these, two patients had only SMA lesion, sixhad both CA and SMA lesions，and five had three branches lesions. No patients withisolated IMA stenosis or occlusion were found.3. Clinical characteristics of107patients with IC:The average age of this group was70years old and the ratio of male/female was3.12:1. Patients were classified into the ulcer group (n=51)and the non-ulcergroup(n=56). In comparison with the non-ulcer group, the ulcer group had higherincidence of chronic constipation, and COPD, and had more patients with enteric-coatedaspirin (P=0.024, P=0.020, P=0.030).There were69patients undertaking abdomen contrast-enhanced CT. Of these,51patients had atherosclerosis or calcification of SMA,CA and IMA.18had no vascularabnormality. In comparison with the non-ulcer group, the ulcer group had a higherincidence of vascular lesion, longer duration of hospitalization，higher WBC counts, andlower hemoglobin values (P=0.027, P<0.05, P=0.020, P=0.044).4. CT imaging characteristics associated with bowel ischemia:In CT imaging analysis,151patients (ASMATE:51，ASMVT:53，NOMI:8，CMI:10，IC:29) were divided into survival group (n=115) and death group (n=36). Incomparison with the survival group, the death group had higher incidence of abdomenfluids, portomesenteric vein gas, pneumatosis intestinalis and pneumoperitoneum(P<0.001, P <0.001, P <0.001, P=0.003).51ASMATE patients were subdivided into the survival group (n=30) and the deathgroup (n=21) and were examined by CT imaging analysis on splanchnic artery vascular.There were33patients with SMAT，and18patients with SMAE. The embolic occlusionwas located on various sites, including distant SMA, middle colon artery, right colon artery, ileocolic artery, jejunal arteries and ileal arteries.11patients(33.33%) withorifice thrombosis of SMA resulted from abdomen aorta lesions. There were26patientswith lumina stenosis associated artery atherosclerosis. Of these,10patients had luminastenosis resulted from abdomen artery calcification and non-calcification lesions.5. CT imaging characteristics of atherosclerosis:No difference was found in the total mean calcium score of examined abdomenartery between the ASMATE petients(n=40) and the non-ICBD controls(n=40)(749.91vs382.36, P=0.361). Predominant mass calcification and circle calcification were foundin ASMATE petients with severe calcification (P<0.001). Whereas dot calcification andstripe calcification were found in the non-ICBD controls. The ASMATE patients hadmore calcification plaque locating at proximal to SMA (P=0.046), larger non-calciumvolume of examined abdomen artery (P=0.031), and smaller orifice diameters of SMA(P<0.001).Conclusions1.(1) Prognostic factors including the peritoneal signs, hypotension, high WBC andneutrophilic leukocyte percentage, low hemoglobin, long duration between the onset ofsymptoms and treatment, mean intestinal resection length, intestine and colon resection,second bowel resection, high incidence of ascites, bloody ascites and ascites exceeding1000ml may all be regarded as predictive markers for ASMAT mortality. Weight lossoccurred more frequently in survival group than in death group, and logistic regressionanalysis showed weight loss was protective factor for ASMAE survival. ASMATpatients were often accompanied by atherosclerotic diseases and required intestine andcolectomy. Patients with atrial fibrillation and peripheral artery embolism were morelikely to have ASMAE.(2) Patients with isolated MVT were more likely to have peritoneal signs and bowelnecrosis and require surgery. Patients with combined MVT often had history ofsplenectomy. ASMVT patients with severe pancreatitis had higher mortality.(3) The intake of NSAIDS and extensive bowel ischemia were predictors of NOMImortality. 2. CMI often occurs in elder patients with atherosclerosis diseases, and single vesselabdominal occlusive disease can cause CGI. The negative result in HP, ulcernon-associated with NSAIDS and gastroenteritis in the older may serve as predictivemarkers for CMI. With the increasing aging and illness course, part of patients mayrecover spontaneously.3. Chronic constipation, history of COPD, enteric-coated aspirin intake and elevatedWBC and lower hemoglobin were independent risk factors for IC with ulcer. Patientswith artery basis lesions often occurred ulcerative lesions of IC. The duration ofhospitalization was significantly longer in ulcerative IC.4. The ascites, portomesenteric vein gas, pneumatosis intestinalis andpneumoperitoneum in bowel CT may serve as predictive markers for death ICBDpatients. Abdomen aorta diseases may be involved in the orifice of SMA and lead tostenosis and thrombus of SMA.5. Mass calcification, circle calcification of abdomen aorta, calcification plaquelocating at proximal to SMA, large non-calcium volume in a specific abdomen arteryand orifice stenosis of SMA caused by non-calcium lesions may be vascular risk factorsof ICBD.6. The ratio of various ICBD types and morbidity by sex in our study was notadequate to present the sex and incidence differences of ICBD in a larger and moregeneral population.