Clinical characteristics, echocardiographic features and long-term outcomes of patients with ischaemic versus non-ischaemic left ventricular thrombus

Background

Left ventricular thrombus (LVT) may develop in patients following myocardial infarction (MI), as well as in ischaemic and non-ischaemic cardiomyopathies, and may result in acute ischaemic stroke. Smaller studies comparing LVT associated with ischaemic and non-ischaemic aetiologies only reported 1-year outcomes or focused on specific subpopulations. We aimed to compare the clinical and echocardiographic characteristics and longer-term outcomes in a large population of patients with ischaemic versus non-ischaemic LVT.

Methods

This was a retrospective study of 552 consecutive patients with echocardiographically-identified LVT from March 2011 to January 2021 at a tertiary centre. Ischaemic LVT included LVT associated with MI and ischaemic cardiomyopathy. Non-ischaemic LVT included cases without evidence of ischaemia. Echocardiographic images were interpreted by trained cardiologists. We studied thrombus resolution as well as 5-year rates of ischaemic stroke and all-cause mortality.

Results

Of the 552 patients, mean age was 59.9 years and 84.4% were male. 492 patients had ischaemic LVT and 60 patients had non-ischaemic LVT. Ischaemic LVT was associated with older age (60.4 versus 55.3 years), male sex (86.8% versus 65.0%), smoking (49.2% versus 25.0%) and hyperlipidaemia (54.3% versus 28.3%). Left ventricular ejection fraction (LVEF) was lower in non-ischaemic LVT (28.9% versus 31.9%). LVEF ≤35% was associated with increased mortality in ischaemic LVT (HR 2.11, 95% CI 1.32–3.38). Rates of thrombus resolution, stroke and all-cause mortality were similar in the 2 groups. Anticoagulation was associated with a lower risk of stroke in ischaemic LVT (HR 0.32, 95% CI 0.16–0.66) and lower mortality in both ischaemic (HR 0.44, 95% CI 0.26–0.72) and non-ischaemic LVT (HR 0.14, 95% CI 0.03–0.61).

Conclusion

Patients with ischaemic LVT were more often older, male, smokers and had cardiovascular co-morbidities compared to those with non-ischaemic LVT. Thrombus resolution, stroke and all-cause mortality rates were similar in both groups. Anticoagulation was associated with lower mortality but this needs to be investigated in future prospective studies.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): CHS was supported by the National University of Singapore Yong Loo Lin School of Medicine's Junior Academic Faculty Scheme

Simultaneous cardio-cerebral infarction: a meta-analysis

BACKGROUND/INTRODUCTION

Cardio-cerebral infarction (CCI), which involves the simultaneous occurrence of acute ischaemic stroke and acute myocardial infarction, has a reported incidence of 0.0009%. Treatment of CCI presents a dilemma to physicians as both conditions are time critical. Despite the need for standardized treatment protocols, published data are sparse.

AIM

We aimed to summarize the reported cardio-cerebral infarction cases in the literature.

DESIGN

Meta-analysis.

METHODS

Four databases, Pubmed, Embase, Scopus and Google Scholar were searched until 25 August 2020. A title and abstract sieve, full-text review and extraction of data were conducted independently by three authors.

RESULTS

A total of 44 cases of CCI were identified from 37 case reports and series; 15 patients (34.1%) were treated using percutaneous coronary intervention (PCI) with stent, 8 patients (18.2%) were treated with a PCI without stent, 10 patients (22.7%) were treated via a cerebral vessel thrombectomy and 8 patients (18.2%) were treated via a thrombectomy of a coronary vessel. For medications, 20 patients (45.5%) were treated with thrombolytics, 10 patients (22.7%) were treated with anticoagulants, 8 patients (18.2%) were treated with antiplatelets and 11 patients (25.0%) were treated with anticoagulants and antiplatelets. Of 44 patients, 10 patients died, and 9 of those were due to cardiac causes. Among the 44 patients, days to death was observed to be a median of 2.0 days (interquartile range (IQR): 1.5, 4.0). The modified Rankin Score was measured in nine patients, with a median score of 2.0 (IQR: 1.0, 2.5) being reported.

DISCUSSION/CONCLUSION

The condition of CCI has substantial morbidity and mortality, and further studies are needed to examine the optimal diagnostic and treatment strategies of these patients.

Small bowel capsule endoscopy in patients with cardiac pacemakers and implantable cardioverter defibrillators: Outcome analysis using telemetry review

AIM: To determine if there were any interactions between cardiac devices and small bowel capsules secondary to electromagnetic interference (EMI) in patients who have undergone small bowel capsule endoscopy (SBCE).

METHODS: Authors conducted a chart review of 20 patients with a cardiac pacemaker (CP) or implantable cardioverter defibrillator (ICD) who underwent continuous electrocardiographic monitoring during their SBCE from 2003-2008. authors searched for unexplained electrocardiogram (ECG) findings, changes in CP and ICD set parameters, any abnormality in transmitted capsule data, and adverse clinical events.

RESULTS: There were no adverse events or hemodynamically significant arrhythmias reported. CP and ICD set parameters were preserved. The majority of ECG abnormalities were also found in pre- or post- SBCE ECG tracings and the CP behavior during arrhythmias appeared appropriate. Two patients seemed to have episodes of undersensing by the CP. However, similar findings were documented in ECGs taken outside the time frame of the SBCE. One patient was observed to have a low signal encountered from the capsule resulting in lack of localization, but no images were lost.

CONCLUSION: Capsule-induced EMI remains a possibility but is unlikely to be clinically important. CP-induced interference of SBCE is also possible, but is infrequent and does not result in loss of images transmitted by the capsule.

Differentiation and tolerance of CD4+ T lymphocytes

The development of effector and memory populations of T lymphocytes is determined by antigen-induced growth and differentiation of naive T cells, and it is regulated by antigen-induced functional tolerance and cell death. CD4+ helper T lymphocytes that vary in their profiles of cytokine production and in effector functions also show distinct responses to antigens and co-stimulatory signals, and they differ in their sensitivity to tolerance induction. Thus, stimuli that trigger T cell growth and differentiation, as well as mechanisms that inhibit T cell expansion, determine both the magnitude and the nature of T cell-dependent immune responses to protein antigens.

High-resolution endoscopic imaging of the GI tract: a comparative study of optical coherence tomography versus high-frequency catheter probe EUS

BACKGROUND

Both optical coherence tomography (OCT) and catheter probe EUS (CPEUS) are candidates for high-resolution imaging of the GI wall, but their potential roles in this clinical context have not been investigated.

METHODS

OCT and CPEUS were used to image normal-appearing portions of the GI tract at the same sites. CPEUS was performed with a 20-MHz or a new 30-MHz catheter probe.

RESULTS

Forty-four histologically confirmed normal sites in 27 patients were evaluated. With OCT, mucosa and muscularis mucosa were clearly seen at all sites. Except for stomach, OCT demonstrated the submucosa in all sites. OCT penetration ranged from 0.7 to 0.9 mm. Microscopic structures such as esophageal glands, intestinal villi, colonic crypts, and blood vessels were easily identified. CPEUS penetration ranged from 10 mm to 20 mm, and 5 to 7 distinct layers were discernible. However, both mucosa and submucosa were seen as thin layers without microscopic detail.

CONCLUSION

OCT resolution is superior to high-frequency CPEUS, but depth of penetration is limited to mucosa and submucosa. OCT images the major structural components of the mucosa and submucosa whereas CPEUS does not. Potentially, OCT and high-frequency CPEUS may be complementary for clinical imaging.

Wire-guided intraductal US: an adjunct to ERCP in the management of bile duct stones

BACKGROUND

Endoscopic retrograde cholangiography (ERC) may misdiagnose bile duct stones if air bubbles are introduced during contrast injection, and it may also fail to diagnose stones in the presence of bile duct dilation.

METHODS

Our aim was to determine whether intraductal US (IDUS) improves the accuracy of cholangiography and whether it is a useful adjunct in the management of bile duct stones. IDUS with a wire-guided US probe was performed after initial ERC in patients in whom bile duct stones were suspected. The diagnostic accuracy of ERC alone was compared with that of ERC plus IDUS.

RESULTS

ERC with IDUS was performed in 62 patients who were suspected to have bile duct stones. Both IDUS and ERC were performed by the same endoscopist, and ERC was performed with a C-arm fluoroscope. The presence of bile duct stones and/or sludge were confirmed after sphincterotomy and extraction in 34 patients. Overall, the accuracy of ERC combined with IDUS in the diagnosis of bile duct stone and/or sludge was higher than that of ERC alone (97% vs. 87%, p < 0.05). With dilated bile ducts, the diagnostic accuracy of ERC combined with IDUS was also higher than that of ERC alone (95.5% vs. 72.7%, p < 0.05). Additional diagnostic information provided by IDUS included identification of cystic duct stones in 5 patients, characterization of bile duct strictures in 2 patients, and choledochal varices in 1 patient. Performance of wire-guided IDUS required 5% of the total procedure time.

CONCLUSIONS

IDUS improves diagnostic accuracy of ERC and is a useful adjunct to ERC when bile duct stones are suspected.

Effectiveness of endoscopy in patients admitted to the intensive care unit with upper GI hemorrhage

BACKGROUND

Esophagogastroduodenoscopy (EGD) is generally indicated for the management of patients admitted to intensive care units (ICUs) with upper gastrointestinal (GI) hemorrhage but its impact in community practice has not been measured. Thus, the effectiveness of 3 EGD factors, viz., accurate initial diagnosis, performance within 24 hours of admission (early EGD), and appropriate intervention, was examined.

METHODS

Records of 214 patients admitted to the ICU of 10 metropolitan hospitals with upper GI hemorrhage were reviewed. Unadjusted and severity-adjusted associations of the 3 EGD factors with length of hospital stay, length of ICU stay, readmission to ICU, recurrent bleeding, surgery, and death were evaluated.

RESULTS

Inaccurate diagnosis occurred in 10% of patients at initial EGD and was associated with significant increases in risk of recurrent bleeding (70% vs. 11%, p < 0.001), rate of surgery (20% vs. 4%, p < 0.05), length of hospital stay (median 7.5 vs. 5 days, p < 0.005), length of ICU stay (median 4 vs. 2 days, p < 0.005), and rate of readmission to ICU (20% vs. 0.6%, p < 0.001). These associations persisted after adjusting for severity of illness. Early EGD performed in 82% of patients was associated with significant severity-adjusted reductions in hospital (-33%: 95% CI [-45%, -18%]) and ICU (-20%: 95% CI [-24%, -3%]) stay. Appropriate intervention at initial EGD, performed in 84% of patients, was associated with reductions in severity-adjusted length of ICU stay (-18%: 95% CI [-32%, 0%]) and rate of recurrent bleeding (odds ratio = 0.37, 95% CI [0.13, 1.06]).

CONCLUSIONS

Early, accurate EGD with appropriate therapeutic intervention is effective as practiced in the community and is associated with improved outcomes for patients with upper GI hemorrhage admitted to the ICU. Inaccurate diagnosis at initial EGD is uncommon but has a significant adverse association with all outcome measures.

Role of Doppler US in acute peptic ulcer hemorrhage: can it predict failure of endoscopic therapy?

BACKGROUND

Recurrent bleeding after successful primary endoscopic hemostasis of acutely bleeding ulcers is a significant problem. This study evaluates endoscopic Doppler ultrasound (US) in assessing risk of recurrent bleeding in patients presenting with acute peptic ulcer hemorrhage.

METHODS

In this prospective, double-blind, nonrandomized trial, patients were enrolled from a single academic institution. Only patients with endoscopically confirmed gastric, duodenal, pyloric, or anastomotic ulcers were enrolled. The therapeutic endoscopist was blinded to the Doppler US signal from the ulcer and based treatment decisions on standard guidelines. A 16 MHz pulsed-wave, linear scanning, US probe was used through the accessory channel of an endoscope to assess for the presence of a Doppler signal.

RESULTS

Fifty-two of 139 screened patients entered the trial (55 Doppler sessions). Endoscopic therapy was performed in 42% (30-day recurrent bleeding rate of 17%). Ulcers that remained persistently Doppler positive immediately after endoscopic therapy had a significantly higher rate of recurrent bleeding than ulcers where the Doppler signal was abolished: 100% versus 11% (p = 0.003). There were no bleeding-related deaths.

CONCLUSIONS

A persistently positive Doppler US signal appears to be a marker of inadequate endoscopic therapy in patients with acutely bleeding peptic ulcers.

Design and implementation of an inpatient disease management program

OBJECTIVE

To describe the development and implementation of an inpatient disease management program.

STUDY DESIGN

Prospective observational study.

PATIENTS AND METHODS

On the basis of opportunities for improving quality or efficiency of inpatient and emergency department care, 4 diagnoses, including congestive heart failure (CHF), gastrointestinal hemorrhage, community-acquired pneumonia and sickle-cell crisis were selected for implementation of a disease management program. For each diagnosis, a task force assembled a disease management team led by a "physician champion" and nurse care manager and identified opportunities for improvement through medical literature review and interviews with caregivers. A limited number of disease-specific guidelines and corresponding interventions were selected with consensus of the team and disseminated to caregivers. Physician and nurse team leaders were actively involved in patient care to facilitate adherence to guidelines.

RESULTS

For quarter 2 to 4 of 1997, there were improvements in angiotensin-converting enzyme inhibitor use, daily weight compliance, assessment of left ventricular function, hospital costs, and length of stay for care-managed patients with CHF. Differences in utilization-related outcomes persisted even after adjustment for severity of illness. For the other 3 diagnoses, the observational period was shorter (quarter 4 only), and hence preliminary data showed similar hospital costs and length of stay for care-managed and noncare-managed patients.

CONCLUSIONS

An interdisciplinary approach to inpatient disease management resulted in substantial improvements in both quality and efficiency of care for patients with CHF. Additional data are needed to determine the program's impact on outcomes of other targeted diagnoses.

Pancreatic duct stents for "obstructive type" pain in pancreatic malignancy

OBJECTIVE

Obstruction of the main pancreatic duct from malignancy with secondary ductal hypertension may be an important contributor to pain. The aim of our study was to determine the efficacy and safety of pancreatic stent placement for patients with "obstructive" pain due to pancreatic malignancy.

METHODS

Pancreatic duct stents were placed in 10 consecutive patients with malignant pancreatic duct obstruction and abdominal pain. Seven patients had "obstructive" type pain and three had chronic unremitting pain. Nine had primary pancreatic ductal adenocarcinoma and one had metastatic melanoma. There were eight women and two men. Mean age was 61 yr (range, 47-80 yr). All patients had dominant main pancreatic duct strictures with proximal dilation. Tumors were unresectable. All patients took potent analgesics before endoscopic stent therapy. Polyethylene pancreatic stents, 5- and 7-French, were successfully placed in seven patients, and self-expanding metallic stents were successfully placed in three patients.

RESULTS

There were no procedure-related complications. One patient required a single repeat examination to replace a migrated stent. Seven patients (75%) experienced a reduction in pain. Analgesia was no longer required in five (50%). Three patients who did not improve had chronic pain rather than "obstructive" pain.

CONCLUSIONS

Pancreatic stent placement for patients with "obstructive" pain secondary to a malignant pancreatic duct stricture appears to be safe and effective. It should be considered as a therapeutic option in these patients. It does not seem to be effective for chronic unremitting pain.

High-resolution endoscopic imaging of the GI tract using optical coherence tomography

BACKGROUND

Optical coherence tomography (OCT) has demonstrated the microscopic structure of the gastrointestinal (GI) tract mucosa and submucosa in vitro. We evaluated a prototype OCT system and assessed the feasibility of OCT in the human GI tract.

METHODS

The 2.4 mm diameter prototype OCT probe, inserted through an endoscope, provides a 360-degree radial scan. Images (6.7 frames/sec) are displayed on a television monitor. Tissue contact is not required. In patients undergoing elective endoscopy, OCT images were obtained of normal mucosa (confirmed by biopsy).

RESULTS

Seventy-two sites were imaged (38 patients): esophagus (21), stomach (12), duodenum (11), terminal ileum (4), colon (15), and rectum (9). Varying the distance between the probe and the mucosal surface produced images of the GI wall of varying depth. When held about 1 mm above the mucosal surface, the images consisted of mucosal structures such as colonic crypts, gastric pits, and duodenal villi. With the probe held against the wall, the OCT image comprised several layers interpreted as mucosa, muscularis mucosae, and submucosa. Structures including blood vessels were evident within the submucosa. A probe with a 0.5 mm working distance to the focal point provided the best images. Reducing the frame rate to 4.0 per second facilitated image interpretation.

CONCLUSIONS

OCT is feasible in the human GI tract and provides interpretable high-resolution images of mucosa and submucosa.

Prospective evaluation of an over-the-wire catheter US probe

BACKGROUND

Pancreaticobiliary strictures identified at endoscopic retrograde cholangiopancreatography (ERCP) can be evaluated by intraductal ultrasonography (US). Two major difficulties are that sphincterotomy may be required and the stricture may not be traversable. We prospectively evaluated the ease and success of intraductal US using a new over-the-wire catheter US probe.

METHODS

Biliary or pancreatic strictures discovered at ERCP were imaged with the new probe. Intraductal US performance times, image clarity, imaging depth and technical ease were measured.

RESULTS

Twenty-one patients with a variety of inflammatory and malignant pancreaticobiliary lesions were studied. Thirteen of the 16 (81%) masses imaged by intraductal US were 10 mm or less in diameter. Sphincterotomy was not required. All strictures traversed by a guidewire were imaged. The sphincter of Oddi was successfully imaged in all patients with intact normal sphincters. Performance of intraductal US was rated as technically easy in all cases and image clarity was rated as good or very good in 15 of 21 (71%) cases.

CONCLUSIONS

The new over-the-wire catheter US probe facilitates intraductal US. Sphincterotomy is avoided and strictures are successfully traversed. This probe makes it possible to image the sphincter of Oddi.

Real-time in vivo imaging of human gastrointestinal ultrastructure by use of endoscopic optical coherence tomography with a novel efficient interferometer design

We report on the design and initial clinical experience with a real-time endoscopic optical coherence tomography (EOCT) imaging system. The EOCT unit includes a high-speed optical coherence tomography interferometer, endoscope-compatible catheter probes, and real-time data capture and display hardware and software. Several technological innovations are introduced that improve EOCT efficiency and performance. In initial clinical studies using the EOCT system, the esophagus, stomach, duodenum, ileum, colon, and rectum of patients with normal endoscopic findings were examined. In these initial investigations, EOCT imaging clearly delineated the substructure of the mucosa and submucosa in several gastrointestinal organs; microscopic structures such as glands, blood vessels, pits, villi, and crypts were also observed.

Use of open access in GI endoscopy at an academic medical center

BACKGROUND

Open access endoscopy systems (those in which endoscopy is performed without prior gastroenterology consultation) are becoming more common in the current cost-conscious environment. The aim of this study was to compare appropriateness and yield of endoscopy for patients referred for open access endoscopy with those for patients who had prior contact with a gastroenterologist. We also evaluated patients' preference for undergoing open access endoscopy as opposed to having prior consultation with a gastroenterologist and compared preparedness for endoscopic procedures between the two groups.

METHODS

The cases of all outpatients referred for upper endoscopy and colonoscopy were assessed prospectively over a 5-month period. American Society for Gastrointestinal Endoscopy (ASGE) guidelines for indications for gastrointestinal endoscopy were used to determine appropriateness of referrals. Significant pathologic findings were rated independently by two investigators using defined criteria. Patients' opinions regarding preparedness for endoscopy and referral preference were measured by means of questionnaires administered before endoscopy.

RESULTS

Eighty-six percent of endoscopies after consultation with gastroenterologists were performed for accepted indications compared with 65% of open access procedures (p < 0.01). Significant pathologic findings were present in 40% of the former group compared with 28% of those undergoing open access endoscopy (p < 0.01). Significant pathologic findings were found in 37% of endoscopies performed for indications listed in the ASGE guidelines compared with 20% for unlisted indications (p < 0.01). Forty percent of patients referred for open access endoscopy would have preferred prior consultation with a gastroenterologist.

CONCLUSION

Patients initially seen by a gastroenterologist are more likely to undergo endoscopy for accepted indications, and the yield of endoscopy is higher than among patients referred through an open access system. The system of open access endoscopy as currently practiced may have to be reassessed.

Toxic epidermal necrolysis in acquired immunodeficiency syndrome treated with intravenous gammaglobulin

A 31-year-old man with the acquired immunodeficiency syndrome who developed toxic epidermal necrolysis (TEN) was successfully treated with intravenous immunoglobulin. He presented with a widespread, blistering skin rash, extensive mucosal ulceration, high-grade fever and pancytopaenia. Nevirapine, a non-nucleoside reverse transcriptase inhibitor, was suspected as the culprit drug, although the patient had been taking this medication for 6 months. The patient also demonstrated an increased number of gamma/delta (gamma delta) T cells that decreased concomitantly with his clinical improvement. This correlation has not been described in TEN previously and may be of pathophysiological significance.

Prospective assessment of the utility of EUS in the evaluation of gallstone pancreatitis

BACKGROUND

The ability to identify common bile duct stones by noninvasive means in patients with acute biliary pancreatitis is limited. The aim of this study was to prospectively evaluate the ability of endosonography (EUS) to identify cholelithiasis and choledocholithiasis and predict disease severity in patients with nonalcoholic pancreatitis.

METHODS

EUS was performed immediately before endoscopic retrograde cholangiopancreatography (ERCP) by separate blinded examiners within 72 hours of admission. Gallbladder findings were compared between EUS and transabdominal ultrasonography (US). Using endoscopic extraction of a bile duct stone as the reference standard for choledocholithiasis, the diagnostic yield of EUS was compared with transabdominal US and ERCP. Features identified during endosonographic imaging of the pancreas were correlated with length of hospitalization.

RESULTS

Thirty-six patients were studied. EUS and transabdominal US were concordant in their interpretation of gallbladder findings in 92% of patients. The sensitivity of transabdominal US, EUS, and ERCP for identifying choledocholithiasis was 50%, 91%, and 92% and the accuracy was 83%, 97%, and 89%, respectively. Length of hospital stay was longer in patients with peripancreatic fluid (9.2 vs. 5.7 days, p < 0.1) and shorter in patients with coarse echo texture (2.6 vs. 7.2 days, p < 0.05) demonstrated on EUS.

CONCLUSIONS

EUS can reliably identify cholelithiasis and is more sensitive than transabdominal US in detecting choledocholithiasis in patients with biliary pancreatitis. EUS may be used early in the management of patients with acute pancreatitis to select those who would benefit from endoscopic stone extraction. The utility of EUS for predicting pancreatitis severity requires further investigation.

Diagnostic value of classical and atypical antineutrophil cytoplasmic antibody (ANCA) immunofluorescence patterns

BACKGROUND

The "classical" antineutrophil cytoplasmic antibody (C-ANCA) pattern seen on indirect immunofluorescence (IIF) is characterised by granular cytoplasmic staining showing central or interlobular accentuation, and is strongly associated with antiproteinase-3 antibodies (PR3-ANCA) and Wegener's granulomatosis. However, many laboratories report C-ANCA in the presence of any cytoplasmic IIF staining, regardless of pattern, which risks reducing the diagnostic value of this pattern.

AIMS

To classify different cytoplasmic ANCA patterns and thus determine whether stringent application of the classical criteria for C-ANCA would produce better correlation between C-ANCA and (1) PR3-ANCA enzyme linked immunosorbent assay (ELISA) results; (2) a diagnosis of systemic vasculitis (including Wegener's granulomatosis).

METHODS

72 sera with cytoplasmic IIF collected over a two year period were analysed by IIF and a commercial PR3-ANCA ELISA kit.

RESULTS

Three IIF patterns were defined: "classical/true" C-ANCA as described above (n = 27 (37.5%)); "flat" ANCA with homogeneous cytoplasmic staining (n = 21 (29%)); and "atypical" ANCA which included all other cytoplasmic patterns (n = 24 (33.5%)). Twenty five of the 27 true C-ANCA sera (92.5%) contained PR3-ANCA (p < 0.0001), but none of the 21 with flat ANCA and only one of the 24 with atypical ANCA. From clinical data on 23 of the 27 true C-ANCA positive patients, 20 (87%) had evidence of Wegener's granulomatosis or systemic vasculitis (p < 0.0001 v the other two patterns). However, none of 19 sera with flat ANCA and clinical data had evidence of systemic vasculitis.

CONCLUSIONS

Restricting the term "c-ANCA" to the "classical" description of central/interlobular accentuation on IIF, will improve its correlation with PR3-ANCA positivity and a diagnosis of systemic vasculitis.

Management of occluded biliary Wallstents

BACKGROUND

Wallstents (Schneider Stent, Inc., USA) used for the palliation of malignant biliary strictures, although associated with prolonged patency, can occlude. There is no consensus regarding the optimal management of Wallstent occlusion.

AIMS

To evaluate the efficacy of different endoscopic methods for managing biliary Wallstent occlusion.

METHODS

A multicentre retrospective study of patients managed for a biliary Wallstent occlusion.

RESULTS

Data were available for 38 patients with 44 Wallstent occlusions, all of which had initial endoscopic management. Twenty four patients had died and 14 were alive after a median follow up of 231 (30-1095) days following Wallstent occlusion. Occlusions were managed by insertion of another Wallstent in 19, insertion of a plastic stent in 20, and mechanical cleaning in five. Endoscopic management was successful in 43 (98%). Following management of the occlusion, bilirubin decreased from 6.0 (0.5-34.3) to 2.1 (0.2-27.7) mg/100 ml (p < 0.05). No complications occurred. The median duration of second stent patency was 75 days (95% confidence interval 43 to 107) after insertion of another Wallstent, 90 days (71 to 109) after insertion of a plastic stent, and 34 days (30 to 38) after mechanical cleaning (NS). The respective median survivals were 70 days (22-118), 98 days (54-142), and 34 days (30-380) (NS). Incremental cost effective analysis showed that plastic stent insertion is the most cost effective option.

CONCLUSION

Although all three methods are equally effective in managing an occluded Wallstent, the most cost effective method appears to be plastic stent insertion.

Palliation of malignant gastric outlet obstruction using an endoscopically placed Wallstent

BACKGROUND

Treatment options for malignant gastric outlet obstruction are limited. Surgical gastrojejunostomy, commonly performed, has significant morbidity and mortality.

METHODS

Over 2 years, we prospectively studied the safety, feasibility, and outcomes for use of a newly designed expandable metal stent (Wallstent Enteral; Schneider, Minneapolis, Minn.) to treat malignant gastric outlet obstruction. Stents 16 to 22 mm in diameter and 60 to 90 mm in length were deployed directly through the endoscope.

RESULTS

Twelve patients (ten women, two men; mean age 59.7 years) underwent stenting. Thereafter, six patients were able to eat a regular diet; three could eat pureed food. In three patients, the procedure was unsuccessful because of multiple obstructions not recognized before stenting (one) and stents deployed too proximally (one) or too distally (one).

CONCLUSIONS

Placement of a newly designed stent through the endoscope is safe and effective palliation for various types of malignant gastric outlet obstruction and significantly improves many aspects of patient quality of life.

Role of endoscopic retrograde cholangiopancreatography for suspected choledocholithiasis in patients undergoing laparoscopic cholecystectomy

BACKGROUND

We report our experience of selective cholangiography in a series of laparoscopic cholecystectomies and evaluate the strategy of using "stricter criteria" to select preoperative endoscopic retrograde cholangiopancreatography (ERCPs).

METHODS

A total of 1847 consecutive laparoscopic cholecystectomies were analyzed for use of cholangiography. A high risk of common bile duct stones (bilirubin level more than 2 mg/dL, jaundice, alkaline phosphatase level more than 150 U/L, pancreatitis, or dilated bile duct and/or stone on ultrasound or CT) was an indication for preoperative ERCP. Selective intraoperative cholangiography was performed for intermediate risk of bile duct stones. The strategy of using "stricter criteria" (jaundice and/or demonstrated bile duct stones on ultrasound or CT) for selecting preoperative ERCP was evaluated retrospectively.

RESULTS

Preoperative ERCP was performed in 135 patients (7.3%) and demonstrated bile duct stones in 43 (32%). Of 36 patients with mild gallstone pancreatitis alone, stones were found only in 6 patients (17%). Selective intraoperative cholangiography was performed in 87 (5%), and stones were found in 2 (2%); 67 (3.6%) postoperative ERCPs were performed for suspected choledocholithiasis, and stones were found in 21 (32%). Applying "stricter criteria" to select preoperative ERCP would predict ductal stones in 56%, whereas 3% of patients with stones would be missed, resulting in a 50% reduction in preoperative ERCPs.

CONCLUSIONS

Even in selected patients considered likely to have choledocholithiasis, the diagnostic yield of preoperative ERCP is low. Using "stricter criteria" to select patients for preoperative ERCP can avoid unnecessary ERCPs.

Portal hypertensive stomapathy: a newly described entity and its successful treatment by placement of a transjugular intrahepatic portosystemic shunt

We report the case of a 68-yr-old woman who had previously undergone a total colectomy and ileostomy for Crohn's disease limited to the colon. She subsequently had recurrent episodes of severe stomal bleeding and was discovered to have micronodular cirrhosis. No definite stomal varices were seen by visual inspection, stomal endoscopy, stomal endosonography, or angiography. Nevertheless, multiple discrete, punctate bleeding pints were seen on the external mucosal surface of the stoma (not at the mucocutaneous junction). Despite undergoing numerous modes of treatment, the bleeding continued. The only successful and effective form of treatment was the placement of a transjugular intrahepatic portosystemic shunt.

Role of costimulators in T cell differentiation: studies using antigen-presenting cells lacking expression of CD80 or CD86

For T cells to be optimally activated, recognition of Ag/MHC complexes by the TCR must be accompanied by a second, costimulatory signal that can be provided efficiently by the related costimulatory molecules CD80 (B7-1) and CD86 (B7-2). Recently, CD80 and CD86 have been implicated as differential determinants of Th1- vs Th2-type cytokine profiles. However, this remains a controversial issue since conflicting results have been obtained in different experimental models both in vivo and in vitro. To investigate the role of CD80 and CD86 in Th subset differentiation, we have examined the cytokine profiles induced in TCR transgenic T cells stimulated by peptide in association with splenic APCs obtained from knockout mice that selectively lack expression of either the CD80 or the CD86 molecule. Our data suggest that CD86, and to a lesser extent CD80, can make significant contributions to the production of both IL-4 and IFN-gamma. However, neither molecule plays an obligatory role in priming for the production of either effector cytokine. Furthermore, CD80 and CD86 contribute to the magnitude of T cell activation, but do not appear to selectively regulate Th1 vs Th2 differentiation.

Role of costimulators in T cell differentiation: studies using antigen-presenting cells lacking expression of CD80 or CD86

For T cells to be optimally activated, recognition of Ag/MHC complexes by the TCR must be accompanied by a second, costimulatory signal that can be provided efficiently by the related costimulatory molecules CD80 (B7-1) and CD86 (B7-2). Recently, CD80 and CD86 have been implicated as differential determinants of Th1- vs Th2-type cytokine profiles. However, this remains a controversial issue since conflicting results have been obtained in different experimental models both in vivo and in vitro. To investigate the role of CD80 and CD86 in Th subset differentiation, we have examined the cytokine profiles induced in TCR transgenic T cells stimulated by peptide in association with splenic APCs obtained from knockout mice that selectively lack expression of either the CD80 or the CD86 molecule. Our data suggest that CD86, and to a lesser extent CD80, can make significant contributions to the production of both IL-4 and IFN-gamma. However, neither molecule plays an obligatory role in priming for the production of either effector cytokine. Furthermore, CD80 and CD86 contribute to the magnitude of T cell activation, but do not appear to selectively regulate Th1 vs Th2 differentiation.

Therapeutic ERCP in outpatients

BACKGROUND

We evaluated the safety of outpatient therapeutic ERCP since most complications are apparent within a few hours.

METHODS

We reviewed 190 patients undergoing planned outpatient therapeutic ERCP from a cohort of 409 consecutive therapeutic ERCP procedures. Patients were selected for outpatient therapeutic ERCP based on relative good health and overnight accommodation near our institution.

RESULTS

Outpatient therapeutic ERCPs included plastic biliary stent insertion (n = 71), biliary sphincterotomy (45), pancreatic stent insertion (28), Wallstent insertion (19), biliary balloon or catheter dilation (10), pancreatic balloon or catheter dilation (8), biliary stone extraction with prior sphincterotomy (7), pancreatic sphincterotomy (5), and duodenal ampullectomy (1). Admission was necessary in 31 (16%) because of complications in 22 (11.6%) and observation of post-ERCP symptoms in 9. Twenty-six (13%) of these patients were admitted directly from the endoscopy unit recovery room and 5 (3%) from home after a median interval of 24 hours following discharge (range 5 to 48 hours). Reasons for admission were pancreatitis in 17, hemorrhage in 3, cholangitis in 3, endoscopic but not clinical hemorrhage in 4, pain in 4, and vomiting in 1. Of the patients who were admitted from home, 3 had pancreatitis (following sphincterotomy in 1, pancreatic stenting in 1, pancreatic balloon dilation in 1) and 2 had hemorrhage (postsphincterotomy in 1 and ampullectomy in 1). In comparison, of the 219 consecutive inpatients undergoing therapeutic ERCP, 28 (13%) developed complications with 1 (0.4%) death.

CONCLUSIONS

A policy of selective outpatient therapeutic ERCP, with admission reserved for those with established or suspected complication, appears to be safe and reduces health care costs.

Toothpick ingestion as a cause of acute and chronic duodenal inflammation

Toothpicks are a common cause of foreign body ingestion. We present two patients with duodenal inflammation secondary to toothpick ingestion. In the first patient, there was acute onset of severe abdominal pain, with findings on computed tomography consistent with marked duodenal inflammation. Endoscopy revealed a toothpick embedded in the wall of the duodenum with associated ulceration. In the second patient, 4 months of chronic abdominal pain was evaluated by upper endoscopy which revealed a toothpick embedded in a 1-cm ulcer found in the third portion of the duodenum. Both patients denied memory of ingestion of the toothpicks. Endoscopic removal of the toothpicks resulted in rapid relief of symptoms.

Utility of parameters measured during pneumatic dilation as predictors of successful dilation

OBJECTIVES

The ability to immediately predict the long term outcome of a pneumatic dilation in achalasia has not been well studied. This study prospectively compared immediate postpneumatic dilation parameters with long term efficacy to determine if any factors predicted a favorable long term outcome.

METHODS

Twenty-nine previously undilated achalasia patients underwent graduated pneumatic dilation with Hurst-Tucker dilators (diameters 2.7, 3.3, 3.7, and 4.1 cm). Dilations began with the smallest dilator followed by an observation period of at least 6 wk to determine clinical response. If no clinical improvement was noted, the next size dilator was used. Immediate postdilation parameters studies included: 1) severity of pain during dilation, 2) amount of blood on the dilator, 3) insufflation pressures during dilation, 4) esophageal emptying of gastrograffin (30 ml), and 5) esophageal emptying of barium sulfate (90 ml).

RESULTS

None of the postdilation parameters studied predicted which patients would have good long term results. Pain during dilation increased with increasing dilator size.

CONCLUSIONS

The degree of pain associated with a pneumatic dilation, the amount of blood noted on the dilator, the difference in pressure required to inflate the dilator at the beginning versus the end of dilation, and the amount of esophageal emptying immediately postdilation did not predict long term outcome.

Feasibility and accuracy of a postcard diary system for tracking healthcare utilization of community-dwelling older persons

OBJECTIVE

To test the feasibility of and to validate a self-report weekly postcard diary of health care utilization.

DESIGN

Case-series and validation study.

SETTING

Community-based sample of fee-for-service and health maintenance organization (HMO) patients.

PARTICIPANTS

A convenience sample of 24 community-dwelling older persons who had failed a self-administered screen and were eligible for a study of outpatient comprehensive geriatric assessment consultation.

MEASUREMENTS

Subjects completed and mailed in a weekly postcard diary documenting medical, counseling, or rehabilitation therapy visits. If a subject did not respond within 10 days after the end of the week, a telephone call was placed to gather the information. For a subset of 10 subjects who were HMO enrollees, all records were reviewed to determine accuracy of the postcard diaries.

RESULTS

Of the 24 subjects enrolled, one HMO enrollee dropped out following hip surgery after 4 weeks of completing diaries. The remaining 23 subjects (96% of total entered) provided complete information for 12 weeks. Telephone follow-up to either obtain or clarify utilization information was required for 22% of subjects. For the subset of 10 HMO subjects, seven underreporting, two overreporting, and one incorrect day errors were detected-a total of 10 errors representing 9% of diaries and 1.3% of patient-days. Kappa as a measure of agreement between the two methods (self-report and chart review) was 0.82 (P < .0001). Compared with chart review, the diary report was 75.0% sensitive and 99.8% specific. Positive and negative predictive values were 91.3% and 99.2%, respectively.

CONCLUSION

These findings suggest that a postcard diary system with telephone follow-up is both a feasible and reasonably accurate method of tracking health care utilization by community-dwelling older persons, although a small percentage will be unable to adhere to this method.

Intrauterine infarction of a pulmonary segment in a full-term newborn. A case report

Intrauterine pulmonary infarction is extremely rare. In a series of 775 stillborn and newborn infants, only a few cases of acute pulmonary infarction were reported. The authors present the findings from a full-term infant who died at 9 hours of age of a chronic pulmonary infarction. Several pathogenic mechanisms, including the entry of placental thromboplastin into the fetal circulation, are discussed.

Endoscopic band ligation of esophageal varices

Endoscopic sclerotherapy of esophageal varices rapidly became the standard initial nonsurgical method for control of hemorrhage. Although in widespread use around the world, the technique is associated with a significant complication rate that excludes it as a potential method for primary prophylaxis. The sclerotherapy technique has been difficult to standardize between different endoscopists and centers, with consequent incongruities in trial results and morbidity. The introduction of endoscopic band ligation heralds the possibility of a simple, reproducible method for acute and chronic treatment of varices and the hope that prophylactic eradication, before the first life-threatening hemorrhage, can be achieved safely and effectively.

NonEBV-related B-cell lymphoma in a renal transplant patient responding to acyclovir and reduction in immunosuppression

A case of polyclonal B-cell pharyngeal lymphoma in a renal transplant patient is reported. No evidence of Epstein-Barr virus involvement was detected, but the lymphoma underwent complete remission with acyclovir and reduction in immunosuppression.

Signal transduction via leukocyte antigen CD43 (sialophorin). Feedback regulation by protein kinase C

CD43 is a constitutively phosphorylated 115-kDa sialoglycoprotein expressed on a variety of blood cells including lymphocytes and monocytes. L10, a mAb directed against CD43, triggers T cell activation and enhances hydrogen peroxide production in monocytes. Activation of mononuclear cells by L10 initiates phosphoinositides hydrolysis, C2+ mobilization, and protein kinase C (PKC) activation. In turn, activated PKC hyperphosphorylates CD43, suggesting a potential role for PKC in the regulation of signaling via CD43. To address this issue, we have analyzed the effect of PKC activation by the tumor promoter PMA on L10-triggered rise in intracellular free Ca2+ concentrations ([Ca2+]i). Treatment of mononuclear cells with PMA profoundly inhibited the increase in [Ca2+]i induced by L10. The inhibition of CD43-mediated signaling by PMA was due, in part, to uncoupling of CD43 from the signal-transducing G protein. This was evidenced by the comparatively modest inhibition by PMA of the increase in [Ca2+]i induced by the direct G protein activator AlF4-. PMA treatment did not affect the surface expression of CD43. However, it induced the hyperphosphorylation of CD43, the extent of which correlated with the inhibition of CD43-mediated increase in [Ca2+]i. Staurosporine, a potent inhibitor of PKC, abrogated the hyperphosphorylation of CD43 and normalized CD43-mediated signaling in PMA-treated cells. Significantly, in the absence of PMA, staurosporine enhanced the rise in [Ca2+]i triggered by L10, suggesting that engagement of CD43 by activating ligands results in feedback inhibition by PKC. It is concluded that activation of PKC inhibits signaling via CD43 by mechanisms involving phosphorylation and uncoupling of CD43 from the signal-transducing apparatus and by distal, post-receptor events.

Signal transduction via leukocyte antigen CD43 (sialophorin). Feedback regulation by protein kinase C

CD43 is a constitutively phosphorylated 115-kDa sialoglycoprotein expressed on a variety of blood cells including lymphocytes and monocytes. L10, a mAb directed against CD43, triggers T cell activation and enhances hydrogen peroxide production in monocytes. Activation of mononuclear cells by L10 initiates phosphoinositides hydrolysis, C2+ mobilization, and protein kinase C (PKC) activation. In turn, activated PKC hyperphosphorylates CD43, suggesting a potential role for PKC in the regulation of signaling via CD43. To address this issue, we have analyzed the effect of PKC activation by the tumor promoter PMA on L10-triggered rise in intracellular free Ca2+ concentrations ([Ca2+]i). Treatment of mononuclear cells with PMA profoundly inhibited the increase in [Ca2+]i induced by L10. The inhibition of CD43-mediated signaling by PMA was due, in part, to uncoupling of CD43 from the signal-transducing G protein. This was evidenced by the comparatively modest inhibition by PMA of the increase in [Ca2+]i induced by the direct G protein activator AlF4-. PMA treatment did not affect the surface expression of CD43. However, it induced the hyperphosphorylation of CD43, the extent of which correlated with the inhibition of CD43-mediated increase in [Ca2+]i. Staurosporine, a potent inhibitor of PKC, abrogated the hyperphosphorylation of CD43 and normalized CD43-mediated signaling in PMA-treated cells. Significantly, in the absence of PMA, staurosporine enhanced the rise in [Ca2+]i triggered by L10, suggesting that engagement of CD43 by activating ligands results in feedback inhibition by PKC. It is concluded that activation of PKC inhibits signaling via CD43 by mechanisms involving phosphorylation and uncoupling of CD43 from the signal-transducing apparatus and by distal, post-receptor events.

T-cell antigen receptor (TCR)-alpha/beta heterodimer formation is a prerequisite for association of CD3-zeta 2 into functionally competent TCR.CD3 complexes

In order to study the relationship between assembly, surface expression, and signal transduction of the alpha/beta T-cell antigen receptor-CD3 complex (TCR.CD3), a series of T-cell mutants with a partial block in assembly of the complex was generated. By chemical mutagenesis, we produced somatic cell variants of the human T-leukemia cell line, HPB-ALL, which expressed low amounts of TCR.CD3 complexes on their surface. RNA and protein analyses demonstrated that most variants synthesized normal amounts of the individual members of the complex, i.e. TCR-alpha, TCR-beta, CD3-gamma, -delta, -epsilon, and -zeta. In these variants, less than 10% of the TCR.CD3 complexes inside the cell contained the CD3-zeta 2 homodimer due to an intrinsic deficiency in the formation of the TCR-alpha/beta heterodimer. The low level of assembly of CD3-zeta 2 into the TCR.CD3 complex and an additional decrease in the rate of export of the TCR.CD3 complex from the endoplasmic reticulum explained the low level of expression of alpha/beta receptors on the surface of these mutants. Only cells with the complete set of subunits of the TCR.CD3 complex on their surface were capable of transducing CD3-mediated signals. The results presented in this paper indicate that TCR-alpha/beta heterodimer formation is an obligatory requirement for assemblage of CD3-zeta 2 into a functionally competent TCR.CD3 complex.

Mechanism of mononuclear cell activation by an anti-CD43 (sialophorin) agonistic antibody

CD43 (sialophorin, gpL115) is a sialoglycoprotein expressed on a wide variety of blood cells including lymphocytes, monocytes, neutrophils, and platelets. L10, an anti-CD43 mAb, has been shown to induce monocyte-dependent activation and proliferation of human T lymphocytes. We have studied the signaling mechanism involved in this activation process. Treatment of PBMC and purified populations of T cells and monocytes with L10 induced the hydrolysis of phosphoinositides with the resultant generation of the phosphoinositide-derived second messengers diacylglycerol and inositol phosphates. This was associated with the translocation of protein kinase C from cytosol to membrane fractions and an increase in free intracellular Ca2+ in treated cells. In human leukemic T cell lines, the magnitude of signaling via CD43 did not correlate with the density of the TCR/CD3 surface expression nor with the intensity of signaling via the TCR/CD3. Moreover, a mutant derived from the leukemic T cell line HPB-ALL that was severely defective in TCR/CD3 surface expression and signaling nevertheless had normal CD43 surface expression and signaling compared with the parent cell line. It is concluded that CD43 is functionally coupled to the phospholipase C/phosphoinositides signaling pathway. In human T cells, signaling via CD43 proceeds independently of TCR/CD3. The widespread expression of CD43 suggests a potentially important role for this molecule in orchestrating the activation of multiple cell types.

Mechanism of mononuclear cell activation by an anti-CD43 (sialophorin) agonistic antibody

CD43 (sialophorin, gpL115) is a sialoglycoprotein expressed on a wide variety of blood cells including lymphocytes, monocytes, neutrophils, and platelets. L10, an anti-CD43 mAb, has been shown to induce monocyte-dependent activation and proliferation of human T lymphocytes. We have studied the signaling mechanism involved in this activation process. Treatment of PBMC and purified populations of T cells and monocytes with L10 induced the hydrolysis of phosphoinositides with the resultant generation of the phosphoinositide-derived second messengers diacylglycerol and inositol phosphates. This was associated with the translocation of protein kinase C from cytosol to membrane fractions and an increase in free intracellular Ca2+ in treated cells. In human leukemic T cell lines, the magnitude of signaling via CD43 did not correlate with the density of the TCR/CD3 surface expression nor with the intensity of signaling via the TCR/CD3. Moreover, a mutant derived from the leukemic T cell line HPB-ALL that was severely defective in TCR/CD3 surface expression and signaling nevertheless had normal CD43 surface expression and signaling compared with the parent cell line. It is concluded that CD43 is functionally coupled to the phospholipase C/phosphoinositides signaling pathway. In human T cells, signaling via CD43 proceeds independently of TCR/CD3. The widespread expression of CD43 suggests a potentially important role for this molecule in orchestrating the activation of multiple cell types.

Proliferation of highly purified T cells in response to signaling via surface receptors requires cell-cell contact

Lymphocyte proliferation is associated with cell-cell aggregation. In order to assess the importance of cell-cell contact in T-cell proliferation we examined the effect of disruption of cellular aggregation by anti LFA-1(4) mAb on T-cell proliferation. Monocyte-dependent T-cell proliferation induced by anti-CD3 mAb, pairs of anti-CD2 mAbs, or PHA was inhibited by anti-LFA-1 mAb. Monocyte-independent proliferation of highly purified T cells to anti-CD3 mAb plus PMA or plus IL-2 and to PHA plus IL-2 was, surprisingly, also inhibited by anti-LFA-1 mAb. Anti-LFA-1 mAb caused the partial inhibition of both low-affinity and high-affinity IL-2 receptor and the complete inhibition of IL-2 synthesis. In contrast to the above, the proliferation of highly purified T cells to PMA plus ionomycin was not inhibited by anti-LFA-1 mAb. These results suggest that optimal activation of highly purified T cells via cell surface receptors requires LFA-1-dependent cell-to-cell contact between proliferating T cells as well as between T cells and accessory cells. Such contact appears to be crucial for initiating IL-2 production and for optimal action of IL-2 through its receptor.

Cardiopulmonary effects of high frequency positive-pressure ventilation versus jet ventilation in respiratory failure

Conventional ventilators are frequently used at high rates in the intensive care nursery to achieve adequate oxygenation and ventilation with reduced peak inspiratory pressure. The efficacy and limitations of high frequency positive-pressure ventilation (HFPPV) using a conventional ventilator were studied by comparing the cardiopulmonary effects of HFPPV with those of high frequency jet ventilation (HFJV) in an animal model of respiratory failure. Sixteen saline-lavaged rabbits were ventilated with either HFPPV or HFJV for 2 h using rates of 200 breaths/min, inspiratory to expiratory ratio of 1:2, and FIO2 of 1.0. As controls an additional eight lavaged rabbits were ventilated at conventional rates (40 to 60 breaths/min). Proximal peak inspiratory pressure as indicated on the ventilator manometer or drive pressure was adjusted to maintain acceptable blood gases. Cardiac output (CO) was measured by thermodilution. Although there was a significant decrease in cardiac function over time, there were no significant differences between the groups in CO or stroke volume. Satisfactory oxygenation and ventilation were maintained in all groups. Static respiratory system compliance and mean airway pressure were similar among the groups. Histologic examination of the lungs revealed no differences between the three ventilator groups. The results of this study indicate that both HFPPV and HFJV are effective in short-term maintenance of normal blood gases in respiratory failure without any discernable differences in their effects on cardiovascular function. At very high rates, however, increases in VT are not possible with HFPPV, which limits its usefulness and flexibility in respiratory failure.