Artificial intelligence for gastroenterology: Singapore artificial intelligence for Gastroenterology Working Group Position Statement.

BACKGROUND: Successful implementation of artificial intelligence in gastroenterology and hepatology practice requires more than technology. There are ethical, legal, and social issues that need to be settled. AIM: A group consisting of AI developers (engineer), AI users (gastroenterologist, hepatologist, and surgeon) and AI regulators (ethicist and administrator) formed a Working Group to draft these Positions Statements with the objective of arousing public and professional interest and dialogue, to promote ethical considerations when implementing AI technology, to suggest to policy makers and health authorities relevant factors to take into account when approving and regulating the use of AI tools, and to engage the profession in preparing for change in clinical practice. STATEMENTS: These series of Position Statements point out the salient issues to maintain the trust between care provider and care receivers, and to legitimize the use of a non-human tool in healthcare delivery. It is based on fundamental principles such as respect, autonomy, privacy, responsibility, and justice. Enforcing the use of AI without considering these factor risk damaging the doctor-patient relationship.

Analysis of variables associated with surgery versus observation in patients with pancreatic cystic lesions referred for endoscopic ultrasound.

BACKGROUND AND STUDY AIM: Endoscopic ultrasound (EUS) with fine-needle aspiration (FNA) for cyst fluid analysis (CFA) is often requested for pancreatic cystic lesions, to determine whether to operate or to observe. If this decision is not influenced by the EUS findings, the procedure may be unjustifiable. We aimed to determine whether EUS-CFA results predict surgery or observation in patients with pancreatic cysts referred for EUS. PATIENTS AND METHODS: Consecutive patients referred to a quaternary pancreaticobiliary center for EUS evaluation of pancreatic cysts were eligible. Clinical data, computed tomography (CT) results, EUS findings, and CFA results were reviewed retrospectively. Statistical analysis was performed to determine variables associated with surgery versus observation. RESULTS: Over 33 months, data on 194 consecutive patients referred for EUS for evaluation of pancreatic cysts were analyzed. Of these, 136 (70 %) patients had EUS-FNA. After the initial workup (including EUS with/without CFA), 35 (18 %) underwent surgery. Predictors of surgery were: younger age (< 65 years) (P = 0.0027), malignant appearance at EUS (P = 0.02), and history of EUS-FNA (P = 0.012). Cyst fluid appearance, and carcinoembryonic antigen (CEA), carbohydrate antigen 19­9 (CA 19­9), and amylase levels were not significant determinants of surgery. In 14/50 (28 %) of cases where EUS-CFA clearly suggested benign serous lesions, surgery was still performed and in 9/11 (82 %) of cases with malignant EUS-CFA findings, surgery was not done. CONCLUSIONS: In patients with pancreatic cysts referred for EUS, age and EUS appearance independently predict surgery. The "perceived need for EUS-CFA" also predicts surgery, but not the EUS-CFA results. The clinical value of EUS-CFA requires further study.

Clinical features and outcome of emergency percutaneous intervention of left main coronary artery occlusion in acute myocardial infarction.

INTRODUCTION: Acute myocardial infarction (AMI) due to left main coronary artery (LMCA) occlusion carries a grave prognosis. Large series reporting on the outcome of emergency revascularisation (percutaneous or surgical) of acute LMCA occlusion have been scarce. We seek to identify, in our local population, the clinical presentation and outcome of this group of patients. METHODS: From January 2000 to December 2005, a total of 1,539 patients underwent primary percutaneous coronary angioplasty for AMI in our institution. 11 patients (0.8 percent) underwent percutaneous intervention to the LMCA. These patients became the subjects of our study. Data on demography, clinical features and outcome was collected from all in-hospital and clinical notes. One sub-investigator, who was blinded to the study outcome, assessed the angiographical features. RESULTS: The overall inpatient mortality was 82 percent (9 out of 11). Nine out of 11 patients presented with cardiogenic shock. All patients presented with shock died during the hospital stay. All patients required intra-aortic balloon counter pulsation insertion. Of the two patients who survived till discharge, one had angioplasty followed by bypass surgery. The remaining one had angioplasty and stenting to the left main artery. Both survivors have been doing well without further major adverse cardiac event after an average of 64 months of follow-up. CONCLUSION: Percutaneous revascularisation of acute LMCA occlusion is feasible and the best outcome is seen in stable patients. Prognosis is still poor in patients with unfavourable clinical features.

Effect of left ventricular shape alteration on contractility and function.

We have investigated the effect of left ventricular (LV) shape on contractility and ejection function. In this study, a new contractility index is developed in terms of the wall stress (sigma*, normalized with respect to LV pressure) by means of an LV ellipsoidal model. Using cine-ventriculography data, the LV ellipsoidal model (LVEM) major (B) and minor axes (A) are derived for the entire cardiac cycle. Thereafter, a new contractility index (CONT1) is derived as dsigma*/dt, incorporating the LV ellipsoidal shape factor. Also, another contractility index (CONT2) was developed in terms of the generated sigma* at the start of ejection phase, and maximized with respect to B/Ashape parameter, to obtain the optimal value of B/Aover the physiological ranges of the ratio of myocardial volume and LV volume. The in vivovalue of B/Aat the start of ejection is compared with this optimal value, and the LV contractility is evaluated in terms of the proximity of the in vivo B/Ato the optimal B/A. The results indicate that a non-optimal less-ellipsoidal shape (or more spherical) is associated with decreased contractility (and poor systolic function) of the LV, associated with a failing heart.

Clinical usefulness of endoscopic ultrasonography-guided fine-needle aspiration in the diagnosis and staging of lung cancer.

Lung cancer is the most common cause of cancer-related mortality in Singapore, and accurate staging of lung cancer is therefore of paramount importance. Several non-invasive and invasive modalities can be used to stage lung cancer. Endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA) is a safe procedure that is performed under conscious sedation and has a sensitivity of up to 90-98 percent in expert hands. In addition, nodal groups that are inaccessible by cervical mediastinoscopy (such as the aortopulmonary window lymph nodes) can be sampled by EUS-FNA. We present three cases in which EUS-FNA was used successfully to diagnose and stage lung cancer, thus avoiding surgery.

Endoscopic ultrasound-guided fine needle aspiration in the evaluation of suspected lung cancer.

BACKGROUND AND AIM: The role of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) in the diagnosis and staging of lung cancer is still not fully explored. This prospective study aimed to define the effectiveness of EUS-FNA as an adjunct to computer tomography (CT) and bronchoscopy in the evaluation of suspected lung cancer in routine clinical practice. METHODS: Over a period of 20 weeks, the data of 16 consecutive patients suspected of lung cancer on account of respiratory symptoms, and/or the findings of either a mass or mediastinal lymph nodes on helical CT, who were referred for evaluation by EUS, were prospectively collected. Fourteen of these patients underwent sequential bronchoscopy followed by EUS-FNA in the same setting. RESULTS: Bronchoscopy was performed in 15 patients, while EUS was performed in all 16 patients. Bronchoscopy diagnosed 9 cases of non-small-cell lung cancer (NSCLC) but was falsely negative in 3 cases of malignancies, which were all established by EUS-FNA of mediastinal lymph nodes (2 cases of NSCLC and 1 case of esophageal squamous cell cancer). EUS-FNA also diagnosed advanced NSCLC in another patient who did not undergo bronchoscopy, such that eventually 13 patients were diagnosed to have malignancies. Distant metastases were diagnosed by EUS-FNA in 4 cases of NSCLC (2 cases of left adrenal gland and 2 cases of pancreatic metastases). Two patients were diagnosed to have sarcoidosis and 1 patient was diagnosed to have pneumoconiosis eventually. CONCLUSIONS: EUS-FNA is useful as an adjunct to CT and bronchoscopy in the evaluation of suspected lung cancer.

Rabeprazole vs esomeprazole in non-erosive gastro-esophageal reflux disease: a randomized, double-blind study in urban Asia.

AIM: Gastro-esophageal reflux disease (GERD) is becoming increasingly common in Asia. Data on the efficacy of proton pump inhibitors in patients with non-erosive GERD (NERD) in Asia is lacking. This double-blind study compared the efficacy and safety of rabeprazole with esomeprazole in relief of symptoms in patients with NERD. METHODS: One hundred and thirty-four patients with reflux symptoms of NERD and normal endoscopy were randomized to receive rabeprazole 10 mg or esomeprazole 20 mg once daily for 4 wk. Symptoms were recorded in a diary and changes in severity of symptoms noted. RESULTS: At 4 wk of treatment, rabeprazole 10 mg and esomeprazole 20 mg were comparable with regards to the primary endpoint of time to achieve 24-h symptom-free interval for heartburn 8.5 d vs 9 d and regurgitation 6 d vs 7.5 d. Rabeprazole and esomeprazole were also similarly efficacious in term of patient's global evaluation with 96% of patients on rabeprazole and 87.9% of patients on esomeprazole, reporting that symptoms improved (P = NS). Satisfactory relief of day- and night-time symptoms was achieved in 98% of patients receiving rabeprazole and 81.4% of patients receiving esomeprazole. Adverse events were comparable in both groups (P = NS). CONCLUSION: Rabeprazole 10 mg has a similar efficacy and safety profile in Asians with NERD as esomeprazole 20 mg. Further study is necessary to investigate whether the small differences between the two drugs seen in this study are related to the improved pharmacodynamic properties of rabeprazole. Both drugs were well tolerated.

Nuclear cardiology in Singapore: a review.

Since its introduction in Singapore more than 10 years ago, nuclear cardiology has now become an integral part of comprehensive cardiac workup of patients with a variety of cardiac diseases. We trace its local development from the 1980s to its present-day role in cardiac evaluation, and into the potential future of genetic and molecular cardiology.

Myocardial infarction in Singapore: a nationwide 10-year study of multiethnic differences in incidence and mortality.

INTRODUCTION AND METHODS: Cardiovascular diseases have progressively increased in importance as a major contributor of morbidity and mortality in Asia. However, many countries in Asia do not have nationwide systematically-collected and standardised data on myocardial infarction (MI). To accurately document the extent of atherosclerotic coronary heart disease in Singapore, a nationwide myocardial infarct registry was established in the mid-1986. Possible myocardial infarct events were identified through daily national lists of cardiac enzymes, hospital discharge codes, mortuary records and the national death registry. Data obtained from clinical history, cardiac enzymes and 12-lead electrocardiogram Minnesota codes were entered into an algorithm based on the WHO MONICA study. Cases identified as "definite" MI were included in the decade's review for this study. RESULTS: From 1988 to 1997, 13,048 myocardial infarct events were diagnosed with 3367 deaths. There was a 39.1% decline in mortality, with an average decline of 6.5% per year [95% confidence intervals (CI), -3.9% to -9.1%]. However, the decline in incidence was only 20.8% with an average decline of 2.4% per year (95% CI, -6.6% to -1.2%). The highest incidence and mortality rates for both genders were seen in the Indians, followed by the Malays and the Chinese. CONCLUSION: Over 10 years, from 1988 to 1997, we documented a significant fall in mortality from MI in Singapore. There was a smaller decline in the incidence of infarction. Singapore implemented a National Healthy Lifestyle Programme in 1992 as a 10-year effort. The disparity in the incidence and mortality may suggest that a more dramatic and immediate impact has taken place in mortality through therapeutic programmes; primary preventive programmes would be more difficult to evaluate and have a more gradual impact. Only with continual accurate data collection through the whole country, over a much longer period, can the relative value of preventive and therapeutic programmes in coronary heart disease be assessed.

An evaluation of point-of-care instrument for monitoring anticoagulation level in adult cardiac patients.

INTRODUCTION: Rapid point-of-care measurement of anticoagulation has become feasible with the advent of new portable devices and offers the potential for home monitoring. This study evaluates the accuracy and feasibility of such a point-of-care device, the ProTime analyser as compared with standard laboratory method (IL MCL2) for monitoring the International Normalised Ratio (INR) level in cardiac patients on oral anticoagulation therapy. MATERIALS AND METHODS: Fifty patients were studied. The majority were male (86% versus 14%). Chinese accounted for 37(74%) whereas Malay and Indian, constituted 9(18%) and 4(8%) respectively. The mean age was 55 +/- 12 years. Prosthetic heart valve replacement (46%) and atrial fibrillation (38%) were among the main indications for anticoagulation. The mean dosage of warfarin was 3.0 +/- 1.5 mg (range 1.0 to 6.5 mg) and the INR results ranged from 0.83 to 4.69 (based on the hospital laboratory method). Fingerstick and venous blood samples were collected from every patient and subjected to analysis by ProTime and IL MCL2 analysers. RESULTS: There was a good correlation of INRs between ProTime venous and IL MCL2 venous, ProTime fingerstick and IL MCL2 venous and ProTime venous and ProTime fingerstick samplings, with correlation coefficients (r) of 0.9248, 0.9403 and 0.9557, respectively. The Bland-Altman plot also showed a good correlation between the methods used without any systematic bias (limits of agreement ranged from -0.422 to +0.606 INR units on average). CONCLUSION: This rapid point-of-care device appears to have an acceptable level of accuracy for measuring INR values in the recommended target ranges in adult cardiac patients on oral anticoagulation therapy.

Validation of 13C-urea breathtest for the diagnosis of Helicobacter pylori infection in the Singapore population.

INTRODUCTION: Several tests are available for determining the presence of Helicobacter pylori (H. pylori) infection. These may be invasive or non-invasive. The carbon urea breath test (C-UBT) is generally considered to be a simple, non-invasive and accurate test for the detection of H. pylori infection both before and after treatment. Commercially available 13C-UBT kits are generally validated in their country of manufacture and the stated accuracy of their tests may not be applicable to our local population. AIM: The aim of our study was to determine the accuracy of a commercial 13C-urea breath test kit, Hp-Plus (Utandningstester i Sverige AB, Sweden), in the Singapore population. PATIENTS AND METHODS: One hundred patients for oesophago-gastro-duodenoscopy (OGD) were recruited into this prospective study. Gastric biopsies were obtained for the biopsy urease test and histological examination. Blood samples were obtained for H. pylori serology. Breath samples were then obtained at baseline and after consumption of 100 mg of labelled 13C-urea. The presence of H. pylori infection was defined by a positive result on any two of the three tests (biopsy urease test, histology, serology) performed for the detection of H. pylori. Using this "gold standard", the sensitivity, specificity, and positive and negative predictive values of the 13C-UBT were calculated. RESULTS: In the Singapore population, the 13C-UBT (Hp plus) has a sensitivity and specificity of 94.2% and 100% respectively for the detection of H. pylori infection. The positive predictive value and negative predictive value of the 13C-UBT is 100% and 88.6% respectively. CONCLUSION: The 13C-UBT is a simple, safe, and accurate non-invasive test for the detection of H. pylori infection, making it a valuable tool in local clinical practice.

Technetium-99m sestamibi for the assessment of myocardial salvage following reperfusion therapy in acute myocardial infarction.

INTRODUCTION: Reperfusion therapy with either thrombolysis or angioplasty has been shown to be beneficial in acute myocardial infarction. Tc-99m sestamibi is a myocardial tracer that can be used to assess myocardial salvage because of its property of very limited redistribution. MATERIALS AND METHODS: To assess the feasibility of this technique locally, Tc-99m sestamibi was injected before and after reperfusion therapy with angioplasty (n = 11) or streptokinase (n = 18) in 29 patients with acute myocardial infarction (anterior = 25, inferior = 4). Single-photon emission computed tomography (SPECT) was performed within 4 hours of reperfusion and repeated 5 to 7 days later. RESULTS: Initial perfusion defect size ranged from 6% to 78% (mean 36.3 +/- 18.7%), and final defect size from 0% to 50% of the left ventricle (mean 23.7 +/- 14.8%, P < 0.001). Patients with proximal left anterior descending artery (LAD) lesions had larger defects compared to those with mid LAD lesions (mean defect size 52% for pLAD versus 28% for mLAD, P < 0.013). However, there were wide variations in initial defect size (myocardium at risk) for a given infarct-related artery location. The mean decrease in defect size was 12% in the 28 patients with patent arteries compared to only 2% in the patient with an occluded artery (47% to 45%). There was no significant difference in amount of salvage between patients who had thrombolysis (mean 13%, P = 0.0003) and patients who had percutaneous transluminal coronary angioplasty (PTCA) (mean 12%, P = 0.005). CONCLUSIONS: Assessment of myocardial salvage is feasible using Tc-99m sestamibi SPECT imaging. It allows for quantitation of myocardium at risk and the amount of myocardial salvage, which is not possible by angiography alone.

The neurological manifestations of Nipah virus encephalitis, a novel paramyxovirus.

A novel Hendra-like paramyxovirus named Nipah virus (NiV) was the cause of an outbreak among workers from one abattoir who had contact with pigs. Two patients had only respiratory symptoms, while 9 patients had encephalitis, 7 of whom are described in this report. Neurological involvement was diverse and multifocal, including aseptic meningitis, diffuse encephalitis, and focal brainstem involvement. Cerebellar signs were relatively common. Magnetic resonance imaging scans of the brain showed scattered lesions. IgM antibodies against Hendra virus (HeV) were present in the serum of all patients. Two patients recovered completely. Five had residual deficits 8 weeks later.

Lipid screening in a volunteer population in Singapore.

Coronary risk profile screening was performed in 1065 volunteers during the National Heart Week 1988 as part of the National Heart Association's campaign against the increasing incidence of ischaemic heart disease. Of particular importance was the use of a desktop analyser for lipid screening of total cholesterol and high density lipoprotein (HDL) cholesterol. It was found that the mean serum cholesterol was 211 +/- 39.5 mg/dl, with 62% of the participants having a total cholesterol greater than 200 mg/dl and 23.1% having a total cholesterol greater than 240 mg/dl. For HDL cholesterol, the mean was 48.4 +/- 17 mg/dl, with 18.7% of the participants having a low HDL cholesterol of less than 35 mg/dl. The male Indians had a significantly lower HDL cholesterol compared to male Malays. Three or more risk factors for coronary artery disease was present in 21.7% of Chinese, 41.2% of Malays and 50% of Indians. We conclude therefore that a proportion of this volunteer population, the majority of which have no overt heart disease, is at risk from coronary artery disease from an elevated cholesterol or low HDL cholesterol level. A follow-up of 90 participants who were initially detected to have an elevated cholesterol in 1986, however, showed that only 54.4% still had an elevated cholesterol of greater than 240 mg/dl, thus suggesting that early detection may help to reduce this risk.

Mortality trends in the coronary care unit.

To evaluate the clinical features, complication rates, and mortality from infarction in the coronary care unit, we analysed all cases of acute myocardial infarction admitted to the Coronary Care Unit of the Singapore General Hospital over a 4 month period in 1988. There were 184 cases of acute infarction with a male:female ratio of 3.4:1. Fifty-five percent of patients were aged 60 years or above. Complications included congestive cardiac failure in 40%, sustained ventricular tachycardia in 9%, cardiogenic shock in 18% and complete heart block in 8%. The overall in-hospital mortality was 20.6%. Multiple logistic regression analysis of clinical variables showed that of the clinical variables, age (elderly patients) and the diabetes were independently associated with a higher mortality as well as development of cardiogenic shock and sustained ventricular tachycardia. Comparing our results with previous smaller studies of CCU outcome in 1975 and 1967, there was a marked increase in the proportion of elderly patients in 1988 but despite this the overall mortality rate was not significantly different. Age is the most important clinical variable predicting outcome from infarction.

Anti-arrhythmic surgery for atrioventricular junctional and atrioventricular re-entrant tachycardia--a report of six cases.

Since 15th March 1989, six patients with recurrent supraventricular tachycardia (SVT) had antiarrhythmic surgery performed. There were 4 males and 2 females, ages ranged from 23 to 62 years (mean 41 years). Two of these patients with the Wolff Parkinson White (WPW) syndrome also had syncope. Five of these patients had atrioventricular re-entrant tachycardia (AVRT) involving the bypass tracts. Two patients with the WPW syndrome had persistent antegrade conduction, two had intermittent conduction and the last patient had no antegrade conduction via the bypass tract. The bypass tracts were localised at the left free wall in all the five patients. Only one patient had atrioventricular junctional re-entrant tachycardia (AVJRT) of the slow-fast type. The indications for surgery for these patients include failed medical therapy, "dangerous" arrhythmias and patient's preference. All the patients had surgery performed using the endocardial dissection technique on the cardioplegic heart. There were no perioperative mortality and morbidity. All the patients were discharged within 2 weeks. To date, none of the patients had clinical recurrence of SVT and only one patient remained in atrial fibrillation and is on digoxin. In conclusion, antiarrhythmic surgery should be considered for patients with "symptomatic" palpitations as it is curative with a resumption to normal life.

Chromosomal abnormalities in couples with recurrent abortions.

Out of 126 couples seeking genetic advice for abortions, 95 couples have experienced 2 or more spontaneous abortions. Of these, chromosome banding studies were carried out in one or both partners (92 women and 85 men). Abnormal karyotypes were found in 2 males. Both abnormalities were balanced translocations: 46 XY t(5q+ 11q-) and 45 XY t(13/14). This represents an overall frequency of 1.1% which is comparable to the reported incidence in the literature.