Context-aware deep network for coronary artery stenosis classification in coronary CT angiography

Automatic coronary artery stenosis grading plays an important role in the diagnosis of coronary artery disease. Due to the difficulty of learning the informative features from varying grades of stenosis, it is still a challenging task to identify coronary artery stenosis from coronary CT angiography (CCTA). In this paper, we propose a context-aware deep network (CADN) for coronary artery stenosis classification. The proposed method integrates 3D CNN with Transformer to improve the feature representation of coronary artery stenosis in CCTA. We evaluate the proposed method on a multicenter dataset (APOLLO study with NCT05509010). Experimental results show that our proposed method can achieve the accuracy of 0.84, 0.83, and 0.86 for stenosis diagnosis on the lesion, artery, and patient levels, respectively.

Acute myocardial infarction and myocarditis following COVID-19 vaccination

Emerging reports raise concerns on the potential association between the COVID-19 vaccines and cardiac manifestations. We sought to evaluate cardiac complications associated with COVID-19 vaccination in a pooled analysis from our institution's cohort study and systematic review. Consecutive patients admitted to a tertiary hospital in Singapore between 1 January 2021 and 31 March 2021, with the onset of cardiac manifestations within 14 days following COVID-19 vaccination, were studied. Furthermore, a systematic review was performed, with PubMed, Embase, Research Square, MedRxiv and LitCovid databases accessed from inception up to 29 June 2021. Relevant manuscripts reporting individual patient data on cardiac complications following COVID-19 vaccination were included. Thirty patients were included in the study cohort, with 29 diagnosed with acute myocardial infarction (AMI) and 1 with myocarditis. Five patients developed heart failure, two had cardiogenic shock, three intubated, and one had cardiovascular-related mortality. In the systematic review, 16 studies were included with 41 myocarditis and 6 AMI cases. In the pooled analysis of the study cohort and the systematic review, 35 patients had AMI and 42 had myocarditis. Majority were men, and myocarditis patients were younger than AMI patients. Myocarditis patients tended to present 72 h postvaccination, while AMI patients were older and typically presented 24 h postvaccination. Majority with AMI or myocarditis developed symptoms after the first and second vaccination dose, respectively. This pooled analysis of patients presenting with cardiac manifestations following COVID-19 vaccination highlights the differences between myocarditis and AMI presentations in temporal association with the vaccination.

Abnormal left atrial strain is associated with eventual diagnosis of atrial fibrillation in patients with embolic stroke of undetermined source

Funding Acknowledgements

Type of funding sources: None.

Background

Patients with embolic stroke of undetermined source (ESUS) have no immediate attributable cause despite initial evaluation. Occult paroxysmal atrial fibrillation (pAF) diagnosed on prolonged electrocardiographic monitoring may be subsequently found in 20% of patients initially classified as ESUS [1]. Anatomic and functional alterations of left atrium (LA) are known to predict pAF in the general population [2]. Recent studies have suggested that LA dysfunction is linked to the risk of development of pAF in stroke patients and may precede LA enlargement [1]. LA strain analysis may be helpful to predict the development of pAF as it can detect subclinical functional impairment [2]. The aim of this study was to analyse whether LA strain can be a marker for the development of new-onset AF in patients with ESUS and sinus rhythm.

Methods

Our single-centre observational cohort study examined 157 patients hospitalised for ESUS in our tertiary hospital between October 2014 and October 2017 who underwent AF monitoring with an implantable loop recorder (ILR). These patients were followed up for occurrence of new-onset pAF and recurrence of ischaemic stroke. All patients underwent transthoracic echocardiography (TTE) during index hospitalisation as part of the workup for ESUS. Echocardiographic images were obtained and analysed post-hoc for two-dimensional (2D) speckle tracing deformation parameters. These LA strain parameters were analysed against the primary outcome of AF detection and secondary outcome of recurrent ischaemic stroke.

Results

A total of 157 ESUS patients, with a mean age of 61.0 (±11.6) years, were followed up for a median duration of 3.5 (interquartile range 3.29) years. ILR monitoring detected AF in 27 patients (17.2%). 27 patients developed recurrent ischaemic strokes. Of the 27 patients with newly diagnosed AF on ILR, 24 (88.9%) were commenced on oral anticoagulation; the remaining 3 patients were not on anticoagulation due to high bleeding risk and frailty.

Patients who had newly diagnosed AF had more impaired left atrial reservoir strain (LASr; 23.5% ± 10.3%, P = 0.042) and left atrial conduit strain (LAScd; -10.5% ± 5.3%, P = 0.003) compared with patients who remained in sinus rhythm. Multivariable logistic regression analysis adjusting for age, sex, hypertension, hyperlipidaemia, diabetes mellitus and left ventricular ejection fraction (LVEF) showed that LAScd was associated with occult AF (adjusted odds ratio [aOR] = 1.110, 95% CI, 1.019-1.209, P = 0.017) and the composite outcome of AF and recurrent ischaemic stroke (OR = 1.069, 95% CI, 1.014-1.138, P = 0.038). Abnormal LAScd was significantly associated with occult AF even when stratified by normal LA volume index (LAVI) (OR = 2.672, 95% CI, 1.035-8.548, P = 0.048) and high LAVI (OR = 1.713, 95% CI, 1.023-2.869, P = 0.041).

Conclusion

Impaired left atrial strain was associated with occult AF detection in patients with ESUS undergoing ILR monitoring.

Higher risk of adverse cardiovascular outcomes in women with type 2 diabetes mellitus: an umbrella review of systematic reviews

Funding Acknowledgements

Type of funding sources: None.

Background

Previous studies have shown that females with type 2 diabetes mellitus (T2DM) may have an excess mortality risk compared to males. Furthermore, other studies have reported sex differences in managing cardiovascular risk factors, such as controlling hypertension and hypercholesterolemia.

Purpose

With the growing evidence from systematic reviews examining the sex differences in cardiovascular outcomes for patients with T2DM, an umbrella review is an essential next step to synthesising and assessing the strength of the available evidence.

Methods

Medline and Embase were searched from inception till 7th August 2022 for systematic reviews and meta-analyses studying the effects of sex on cardiovascular outcomes in T2DM patients. Results from reviews were synthesised with a narrative synthesis, with a tabular presentation of findings and forest plots for reviews that performed a meta-analysis. AMSTAR 2 tool was used to assess the methodological quality of included reviews, while the GRADE assessment was used to assess the quality of evidence for outcomes.

Results

A total of 28 studies evaluating sex differences in cardiovascular outcomes were included. Females with T2DM had a higher risk of developing coronary heart disease (CHD; RRR 1.52, 95%CI 1.32–1.76, p<0.001), acute coronary syndrome (ACS; RRR 1.38, 95%CI 1.25–1.52, p<0.001), and heart failure (RRR 1.09, 95%CI 1.05–1.13, p<0.001) than males. In terms of mortality outcomes, females had a higher risk of all-cause mortality (RRR 1.13, 95%CI 1.07–1.19, p<0.001), cardiac mortality (RRR 1.49, 95%CI 1.11–2.00, p=0.009) and CHD mortality (RRR 1.44, 95%CI 1.20–1.73, p<0.001) as compared to males. In patients undergoing percutaneous coronary intervention, females reported higher odds of MACE (OR 1.49, 95%CI 1.07–2.07, p=0.020) and all-cause mortality (OR 1.71, 95%CI 1.46–2.00, p<0.001) compared to males. Females in Asia (RRR 1.12, 95%CI 1.03–1.21, p=0.006) and North America (RRR 1.10, 95%CI 1.08–1.12, p<0.001) were at increased risk of all-cause mortality while females in Western countries had an increased risk for cardiac death (RRR 1.84, 95%CI 1.45–2.32, p<0.001) compared to males. Six reviews were rated as high in quality; eight reviews were rated as moderate, and fourteen reviews were rated as low in quality. Regarding the quality of outcomes, all outcomes in non-interventional studies had a moderate quality of evidence, while all outcomes in interventional studies achieved a high quality of evidence.

Conclusions

This umbrella review evaluated the quality of meta-analyses and demonstrated that females with T2DM have a higher risk of cardiovascular outcomes than their male counterparts. Future studies examining the sex differences in outcomes should attempt to address the heterogeneity and epidemiological factors for a better quality of evidence. Policymakers should consider sex-specific differences in implementing effective tailored strategies to tackle T2DM.

Effects of epicardial adipose tissue volume and thickness assessed by computed tomography and echocardiography on cardiovascular and cerebrovascular outcomes: a systematic review and meta-analysis

Funding Acknowledgements

Type of funding sources: None.

Background

Epicardial adipose tissue (EAT) has garnered attention as a potential imaging biomarker for the risk stratification of cardiovascular diseases (CVD). However, the prognostic utility of EAT due to inter-ethnic differences and imaging modality (computed tomography (CT) or transthoracic echocardiography (TTE)) remains undetermined.

Purpose

To evaluate the effect of EAT volume and thickness on cardiovascular and cerebrovascular outcomes. We also aim to compare the prognostic utility between CT volumetric and TTE thickness quantification; and provide consolidated data on the heterogeneity in EAT measurements across different ethnic groups.

Methods

Medline and Embase databases were searched from inception till 16 May 2022 for studies that measured EAT volume or thickness of adult patients at baseline and reported follow-up data on outcomes of interest. Outcomes included MACE, all-cause mortality, cardiac death, myocardial infarction (MI), coronary revascularisation, atrial fibrillation (AF), and stroke. Statistical analyses were conducted on Review Manager 5.4.1 to obtain unadjusted and adjusted hazard ratios (HR) and odds ratios (OR) with the results presented on forest plots.

Results

Twenty-nine studies comprising 19709 patients were included in our analysis. Increased EAT thickness and volume were associated with higher risks of MACE (adjusted HR [aHR] 1.46, 95%CI 1.25–1.71, p<0.001), cardiac death (OR 2.53, 95%CI 1.17–5.44, p=0.020), MI (OR 2.63, 95%CI 1.39–4.96, p=0.003), coronary revascularisation (OR 2.99, 95%CI 1.64–5.44, p<0.001), AF (aOR 4.04, 95%CI 3.06–5.32, p<0.001), and stroke (HR 1.02, 95%CI 1.01–1.03, p<0.001). CT-volumetric quantification of EAT conferred a larger MACE risk (aHR 1.79, 95%CI 1.47–2.17, p<0.001) compared to TTE thickness quantification (aHR 1.20, 95%CI 1.09–1.32, p<0.001). Studies originating from North America (HR 1.91, 95%CI 1.26–2.89, p=0.002) and Asia (HR 1.60, 95%CI 1.09–2.36, p=0.020) demonstrated a significantly higher risk of MACE with increased EAT thickness and volume. However, this significance was not seen in European studies (HR 1.48, 95%CI 0.99–2.20, p=0.060). Subgroup differences were also noted across the studies’ countries of origin when analysing the association of EAT and MI (p=0.020). European studies reported a higher magnitude of MI risk associated with higher EAT thickness and volume (OR 5.28, 95%CI 2.34–11.95, p<0.001) as compared to Asian studies (OR 1.75, 95%CI 1.05–2.92, p=0.030). No differences were noted across other outcomes in the subgroup comparisons by geographical region and between CT and TTE quantification of EAT.

Conclusion

The utility of EAT as an imaging biomarker for predicting and prognosticating CVD is promising. Future efforts to harmonise the EAT parameter thresholds, based on the type of imaging modality and the target population’s ethnic characteristics, will be the next important step before including EAT in CVD prediction models.

Metabolic associated fatty liver disease increases risk of adverse events after acute coronary syndrome

 

Metabolic Associated Fatty Liver Disease (MAFLD) was recently introduced as an alternative definition for fatty liver, that has been linked to an increased risk of systemic end-organ damage. However, current studies have not examined the impact of MAFLD on patients presenting with acute coronary syndrome (ACS). Here, we present a retrospective analysis on the short and long-term outcomes of ACS patients with MAFLD.

Methods

A retrospective analysis was conducted in a tertiary care centre. Hepatic steatosis and fibrosis was examined with hepatic steatosis index and fibrosis-4 (FIB-4) index. The primary and secondary outcomes of the analysis were long term all-cause mortality, and in-hospital all-cause mortality, stroke, heart failure and cardiogenic shock respectively. Adjusted analysis was conducted for primary and secondary outcomes with covariates including age, sex, race, type of ACS and previous myocardial infarction.

Results

A total of 5770 patients were included in the analysis, and 21% of ACS patients had concomitant MAFLD. MAFLD resulted in a 23% increase in long-term all-cause mortality compared to non-MAFLD (HR: 1.230, CI: 1.065 to 1.420, p=0.005). MAFLD increased the risk of in-hospital mortality, stroke, heart failure and cardiogenic shock compared to non-MAFLD. A sensitivity analysis conducted based on MAFLD with advance fibrosis, chronic kidney disease and diabetes also demonstrated significantly increased effect size magnitude of all-cause mortality, compared to non-MAFLD.

Conclusion

MAFLD represents an encapsulation of metabolism dysregulation and has been associated with increased risk of systematic disease. The present study shows that MAFLD is associated with significantly increased adverse prognostic outcomes after ACS compared to non-MAFLD. An increase in awareness of MAFLD is required beyond the field of hepatology for improvements in multidisciplinary care and management.

Funding Acknowledgement

Type of funding sources: None.

Reconstructed meta-analysis of percutaneous coronary intervention versus coronary artery bypass grafting for left main disease

Background

Randomized controlled trials (RCTs) comparing percutaneous coronary intervention (PCI) with drug-eluting stents and coronary artery bypass grafting (CABG) for patients with left main coronary artery disease (LMCAD) have reported conflicting results.

Objectives

We performed a systematic review from inception to 23 May 2021 and one-stage reconstructed individual-patient data meta-analysis (IPDMA) that included 10-year mortality outcomes.

Methods

The primary outcome was 10-year all-cause mortality. Secondary outcomes included myocardial infarction (MI), stroke and unplanned revascularization at 5 years. We did IPDMA using published Kaplan-Meier curves to provide individual data points in coordinates and numbers at risk were used to increase the calibration accuracy of the reconstructed data. Shared frailty model or, when proportionality assumptions were not met, a restricted mean survival time model were fitted to compare outcomes between treatment groups.

Results

Of 583 articles retrieved, 5 RCTs were included. A total of 4595 patients from these 5 RCTs were randomly assigned to PCI (N=2297) or CABG (N=2298). The cumulative 10-year all-cause mortality after PCI and CABG was 12.0% versus 10.6% respectively (HR 1.093, 95% CI: 0.925–1.292; p=0.296). PCI conferred similar time-to-MI (RMST ratio 1.006, 95% CI: 0.992–1.021, p=0.391) and stroke (RMST ratio 1.005, 95% CI: 0.998–1.013, p=0.133) at 5 years. Unplanned revascularization was more frequent following PCI compared with CABG (HR 1.807, 95% CI: 1.524–2.144, p<0.001) at 5 years.

Conclusion

This meta-analysis using reconstructed participant-level time-to-event data showed no statistically significant difference in cumulative 10-year all-cause mortality between PCI versus CABG in the treatment of LMCAD.

Funding Acknowledgement

Type of funding sources: None.

Coronary artery bypass grafting versus percutaneous coronary intervention with stenting for multivessel coronary artery disease without left main coronary disease:reconstructed individual patient data

Background and aims

Data are emerging on 10-year mortality comparing coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) with stenting for multivessel disease (MVD) without left main (LM) involvement. We conducted an updated two-stage meta-analysis using reconstructed individual patient data to compare long-term mortality between CABG and PCI for patients with MVD without significant LM coronary disease.

Methods

Medline and Embase databases were searched for articles comparing CABG with PCI for MVD. A two-stage meta-analysis was conducted using reconstructed patient level survival data for all-cause mortality with subgroups by SYNTAX score. The shared-frailty and stratified Cox models were fitted to compare survival endpoints.

Results

We screened 1496 studies and included six randomized controlled trials with 7181 patients. PCI was associated with greater 10-year all-cause mortality risk (HR: 1.282, CI: 1.118–1.469, p<0.001) compared with CABG. In patients with low SYNTAX score, 10-year all-cause mortality after PCI was comparable to CABG (HR: 1.102, 0.822–1.479, p=0.516). However, in patients with moderate to high SYNTAX score, 10-year all-cause mortality was significantly higher after PCI compared with CABG (HR: 1.444, 1.122–1.858, p<0.001; HR: 1.856, 1.380–2.497, p<0.001 respectively).

Conclusion

This updated reconstructed individual patient-data meta-analysis revealed a sustained lower cumulative all-cause mortality of CABG over PCI for multivessel disease without LM involvement.

Funding Acknowledgement

Type of funding sources: None.

Spatial-temporal lipidomics profile of acute myocardial injury

Background

Lipidome disturbance has long been recognized to occur after myocardial infarction (MI). Accumulation of excessive fatty acids induces production of reactive oxygen species and consequently deteriorates cardiac injury in MI. However, the spatial and temporal lipid profile in the heart following ischemic injury remains unknown.

Purpose

We aim to uncover the temporal-spatial lipidome profile of the heart following ischemia reperfusion (I/R) injury and identify circulating lipids released from injured myocardium that are potentially useful for diagnosis of ischemic heart disease.

Methods

C57/BL6 mice were subjected to 30 min myocardial ischemia followed by removal of the ligature to establish reperfusion injury. Porcine I/R injury was induced by 105 min myocardial ischemia followed by reperfusion. Human plasma was obtained from 143 post-MI patients. Myocardial lipid profiles were generated by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MALDI-MSI) in different regions (infarct, remote and peri-infarct) at different time points. Moreover, the lipids in the heart and plasma were analysed by LC-MS/MS.

Results

We observed a drastic alteration in the lipidome with distinct spatial-temporal features in the injured heart by both MALDI-MSI and LC-MS/MS. In the infarct heart tissue, as revealed by LC-MS/MS, we observed an elevation of glycerolipids that peaked at 3 hours after I/R, and a sustained elevation of phospholipids and sphingolipids up to 3 days. Similar alternations in lipid profile was observed but much weaker in the remote and peri-infarct heart tissue compared to the infarct tissue. Among those lipids, PC 32:0 detected by MALDI-MSI highly overlapped CD68 staining at a single-cell level, showing a strong correlation of PC 32:0 with macrophage infiltration in mouse hearts (R2=0.93, p<0.0001). A similar increase of PC 32:0 in the infarct area was also observed in porcine hearts following I/R injury. Surprisingly, plasma levels of PC 32:0 in the mice decreased after I/R injury. In humans, plasma levels of PC 32:0 in post-MI patients were lower than that in healthy individuals (p=0.03). Further analysis demonstrated that plasma levels of PC 32:0 determined within 72 hours after percutaneous coronary intervention were negatively correlated with the 6-month post-MI cardiac ejection fraction in patients (R2=0.08, p<0.001).

Conclusions

A temporal-spatial lipidome profile was established in heart injury by synergizing LC-MS/MS and mass spectrometry imaging. PC 32:0 levels are positively correlated with myocardial macrophage infiltration but negatively correlated with cardiac function in cardiac I/R injury. Our findings indicate that PC 32:0 is a potential biomarker for cardiac injury and the inflammatory status in the injured heart.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Singapore Ministry of Health's National Medical Research Council

A 10-year cohort on prognostic outcomes in patients presenting with acute myocardial infarction complicated by cardiogenic shock and/or cardiac arrest

Background

Cardiogenic shock (CS) and cardiac arrest (CA) complicating acute myocardial infarction (AMI) portend unfavourable outcomes. This study examined the prognosis of patients presenting with AMI complicated by CS and/or CA.

Methods

Consecutive patients presented with AMI to a percutaneous coronary intervention-capable tertiary institution between 2011 and 2021 were studied. Patients were stratified based on the presence or absence of CS (CS+ or CS−) and CA (CA+ or CA−). The primary outcome was 30-day cardiovascular-related mortality. Subgroup analyses based on AMI-type and sex were conducted. Kaplan-Meier curves for cardiovascular-related mortality based on the AMI-type and sex were constructed.

Results

The study included 11,608 AMI patients, 283 of whom had CS+/CA+, 1,068 had CS+/CA−, 54 had CS−/CA+ and 10,203 had CS−/CA−. Cardiovascular-related mortality was significantly higher for CS+/CA+ (57.6%), followed by CS+/CA− (41.6%), CS−/CA+ (20.4%) and CS−/CA− (2.4%). Kaplan-Meier curves demonstrated CS+/CA+ group had the highest mortality (HR=36.26; 95% CI: 29.71–44.25, p<0.001), followed by CS+/CA− (HR=21.59; 95% CI: 18.47–25.24, p<0.001) and CS−/CA+ (HR=9.18; 95% CI: 5.02–16.80, p<0.001), with CS−/CA− as the reference. Those with NSTEMI had consistently higher cardiovascular-related mortality rates than their STEMI counterparts for all groups, apart from the CS+/CA+ group. The sex-specific analysis demonstrated that the survival curves for females with CS+/CA+, CS+/CA− and CS−/CA+ converged, whilst the survival curves for males diverged over time. The multivariable Cox regression revealed the presence of CS and CA are independent predictors of cardiovascular-related mortality, but not NSTEMI, when adjusted for age, gender, diabetes, left ventricular ejection fraction, chronic renal failure, and culprit vessel.

Conclusions

AMI associated with CA and CS portends the least favourable survival, followed by those with CS or CA alone. Excess mortality was observed in the traditionally perceived lower-risk groups, particularly in women. This calls for increased awareness amongst clinicians when managing this subset of high-risk patients.

Funding Acknowledgement

Type of funding sources: None.

Higher long-term mortality in patients with concomitant acute coronary syndrome and aortic stenosis

Background

Aortic stenosis (AS) and acute coronary syndrome (ACS) share similar cardiovascular risk factors, and their concomitant presentation is increasing in incidence with the aging population. Yet literature regarding the prognosis of patients with concomitant ACS and AS remains scarce.

Methods

This retrospective cohort study examined consecutive patients presenting with ACS (ST-segment elevation myocardial infarction [STEMI] and non-STEMI [NSTEMI]) and concomitant AS between 1 January 2011 and 31 March 2021 in a tertiary hospital. The cohort was divided into mild, moderate and severe AS based on index echocardiogram. The primary outcome was all-cause mortality. Kaplan-Meier curves were constructed to compare all-cause mortality among the three groups of patients, based on ACS type and left ventricular ejection fraction (LVEF). Multivariable Cox regression was performed to identify independent predictors of all-cause mortality.

Results

Of a total of 563 patients, 264 had mild (46.9%), 193 moderate (34.3%) and 106 severe AS (18.8%). The mean follow-up duration was 2.5 (± 2.4) years. Majority of patients (72.5%) presented with NSTEMI. Patients with moderate and severe AS had higher rates of all-cause mortality compared to those with mild AS (49.7% vs. 51.4% vs. 35.6% respectively, p=0.002). Concomitant moderate (HR 1.439, 95% CI 1.012–2.048, p=0.043) and severe AS (HR 1.844, 95% CI 1.159–2.933, p=0.010) were independent predictors of all-cause mortality after adjusting for age, gender, LVEF, ACS type, chronic kidney disease, diabetes, hypertension, coronary artery bypass grafting and aortic valve replacement as a time-dependent variable. The Kaplan-Meier curves demonstrated excess mortality in moderate and severe AS, compared to the mild AS group (p<0.001), with similar survival trends observed in the STEMI and the NSTEMI groups, as well as those with preserved LVEF.

Conclusion

Regardless of the ACS presentation type, long-term excess mortality in those with concomitant moderate or severe AS was observed. The adverse prognosis typically observed in patients with concomitant severe AS, in the setting of ACS, extends to patients with moderate AS.

Funding Acknowledgement

Type of funding sources: None.

Association of body mass index with long-term outcomes after elective and semi-urgent percutaneous coronary intervention

Background

While obesity is associated with cardiovascular mortality and morbidity, patients with higher body mass index (BMI) may have better outcomes post-percutaneous coronary intervention (PCI). This “obesity paradox” is controversial and needs clarification.

Purpose

We aimed to investigate the relationship between BMI and outcomes post-PCI in an Asian cohort.

Methods

A retrospective cohort study was performed on consecutive patients who underwent semi-urgent PCI for non-ST elevation myocardial infraction or unstable angina, and elective PCI for stable angina from January 2014 to December 2015 in a tertiary centre. Patients were underweight (BMI <18.5), normal weight (BMI 18.5–22.9), overweight (BMI 23–24.9), pre-obese (BMI 25–29.9) or obese (BMI ≥30), according to the WHO Asian classification. The primary endpoint was all-cause mortality. The secondary outcomes were subsequent events of stroke or transient ischemic attack, myocardial infarction (MI) and congestive cardiac failure (CCF).

Results

1,610 patients were followed up for 3.71 (±0.97) years, 19.7% were female and mean age was 62.1 years (Table 1). BMI showed a U-shaped relationship with the incidence of death (p<0.001), MI (p=0.005), and CCF (p<0.001) (Figure 1A), which was also shown on Kaplan Meier analysis (Figures 1B-E). With reference to normal weight patients on multivariable Cox analysis, overweight (adjusted HR 0.64, 95% CI 0.42–0.97) and pre-obese (adjusted HR 0.55, 95% CI 0.38–0.80) patients had lower mortality. Underweight patients had higher risk (adjusted HR 2.12, 95% CI 1.01–4.46), while pre-obese patients had lower risk of MI (adjusted HR 0.56, 95% CI 0.34–0.92) compared to normal weight patients. Underweight and obese patients had higher risk of CCF (underweight: adjusted HR 3.05, 95% CI 1.45–6.42; obese: adjusted HR 1.86, 95% CI 1.03–3.35) compared to normal weight patients.

Conclusion

Patients at the lower and upper extremes of BMI demonstrated higher risk of mortality, MI and CCF post-PCI.

Funding Acknowledgement

Type of funding sources: None.

The prognostic outcomes of acute myocardial infarction stratified according to metabolic health and obesity status

Background

There has been emerging evidence on the favourable cardiovascular disease incidence in non-obese subjects with healthy metabolism. However, little is known regarding the prognosis across the metabolic phenotypes once cardiovascular disease is established. This study examines the prognosis of patients with acute myocardial infarction (AMI) stratified according to metabolic health and obesity status.

Methods

A retrospective study conducted in a tertiary hospital between 2014–2021. Consecutive patients with AMI were allocated into 4 groups based on metabolic and obesity profile: metabolically healthy obesity (MHO), metabolically healthy non-obesity (MHNO), metabolically unhealthy obesity (MUO) and metabolically unhealthy non-obesity (MUNO). The primary outcome was all-cause mortality. Cox regression examined the independent association between mortality and metabolic phenotypes, adjusting for age, sex, AMI type and ejection fraction.

Results

A total of 9958 patients were studied with majority (68.5%) in the MUNO group, followed by MUO (25.1%), MHNO (5.6%), and MHO (0.8%). MHO patients had lowest mortality (7.4%), followed by MHNO (9.7%), MUO (19.2%) and MUNO (22.6%, p<0.001). Relative to MHNO, MUO (HR 1.610, 95% CI 1.198–2.163, p=0.002) and MUNO (HR 1.383, 95% CI 1.043–1.835, p=0.024) had significantly higher mortality risk, but not MHO (HR 1.514, 95% CI 0.649–3.534, p=0.337), after adjusting for confounders. Kaplan-Meier curves showed favourable survival in metabolically healthy groups with clear divergence from metabolically unhealthy groups (p<0.001). There were stepwise increments in mortality with increasing number of metabolic risk factors regardless of obesity status (p<0.001). Favourable survival was observed in overweight and obese versus normal weight patients regardless of metabolic health.

Conclusion

Metabolically healthy AMI patients had favourable prognosis compared to metabolically unhealthy patients. The obesity paradox was observed in the AMI cohort, but the beneficial effects of obesity appeared not as pronounced in magnitude as in metabolically healthy groups.

Funding Acknowledgement

Type of funding sources: None.

Medication chart review at end of life of paediatric palliative patients

AIM

This study aimed to review the use of medications in a paediatric palliative care (PPC) population during the last two weeks of life.

METHODS

This is a retrospective observational cohort study that included 50 consecutive patients who were referred to KK Hospital PPC service from 2011 to 2015. Those who died after two weeks from discharge date were excluded. Medication charts were reviewed and relevant data were extracted.

RESULTS

The study population included 42 patients and consists predominantly oncological and neurological diagnoses. The median number of medications used was 11.5. Ninety-five percent (40 out of 42) of study population required analgesia where 81% (34 out of 42) were opioid. There was prevalent use of antibiotics (86% of study population, 36 out of 42). Less frequently used medications included steroids, sedatives, laxatives and antiemetics (48%, 52%, 48% and 38% of study population respectively).

CONCLUSION

Significant number of medications was used in PPC during the last two weeks of life. Apart from significant use of analgesia, there is also notable use of antibiotics. Future directions in education such as prescription of laxatives with opioid are proposed.

Association of anesthetic and surgical risk factors with outcomes of initial diagnostic biopsies in a current cohort of children with anterior mediastinal masses

Background

Diagnostic biopsies of pediatric anterior mediastinal masses (AMMs) are high-risk procedures in which general anesthesia (GA) is traditionally avoided. However, awareness of historically recognized risk factors and corresponding perioperative management have improved over time and may now no longer strictly preclude the use of GA. Therefore, in this study, we examined the association of anesthetic and surgical risk factors and modalities with resulting procedural and survival outcomes in a current patient cohort.

Methods

We retrospectively reviewed charts of 35 children with AMMs who underwent initial diagnostic biopsies between January 2001 and August 2019, and determined tracheal compression and deviation from archival CT scans and procedural and disease outcomes.

Results

Twenty-three (65%) patients underwent GA while 12 (35%) received sedation. Among patients with available CT measurements, 13 of 25 (52%) had >50% anteroposterior tracheal diameter reduction. Patients with >50% anteroposterior tracheal compression received sedation more frequently (p=0.047) and were positioned upright (p=0.015) compared with patients with ≤50% compression, although 4 of 13 and 9 of 12, respectively, still received GA. Intraoperative adverse events (AEs) occurred in four (11.4%) patients: three received GA, and all were positioned supine or lateral. AEs were not associated with radiographic airway risk factors but were significantly associated with morphine and sevoflurane use (p<0.001) and with thoracoscopic biopsies (p=0.035). There were no on-table mortalities, but four delayed deaths occurred (three related to disease and one from late procedural complications).

Conclusions

In a current cohort of pediatric AMM biopsies, patients with >50% anteroposterior tracheal compression were more frequently managed with a conservative perioperative management strategy, though not completely excluding GA. The corresponding reduction in frequency of procedural AEs in this traditionally high-risk group suggests that increased awareness of procedural risk factors and appropriate risk-guided perioperative management choices may obviate the procedural mortality historically associated with pediatric AMM biopsies.

Tissue factor cytoplasmic domain exacerbates post-infarct left ventricular remodeling via orchestrating cardiac inflammation and angiogenesis

Introduction

The coagulation protein tissue factor (TF) regulates inflammation and angiogenesis via its cytoplasmic domain in infection, cancer and diabetes. While TF is highly abundant in the heart and implicated in cardiac injuries and dysfunction, the contribution of its cytoplasmic domain in cardiac pathology remains unclear.

Purpose

We aimed to investigate the contribution of the cytoplasmic domain of TF to post-infarct myocardial injury and adverse left ventricular (LV) remodeling.

Methods and results

Myocardial infarction was induced by permanent occlusion of the left anterior descending coronary artery. Male mice with C57BL/Jax background were used for the study. Compared with wild-type mice, mice lacking the TF cytoplasmic domain (TFΔCT) had a higher survival rate (90.5% versus 70%, p=0.0298) during a 28-day follow-up after myocardial infarction. Among surviving mice, TFΔCT mice had better cardiac function and less LV remodeling (ESV: 114.5±13.1mL for WT, 67.06±10.8mL for TFΔCT, p&lt;0.001; EDV: 146.6±12.4mL for WT, 99.97±11.71mL for TFΔCT, p&lt;0.001) than wild-type mice. Bone marrow chimerism indicated that deletion of the TF cytoplasmic domain in either bone marrow-derived cells or cardiac resident cells could alleviate post-infarct cardiac dysfunction. Speckle-tracking strain analysis revealed that the overall improvement of post-infarct cardiac performance in TFΔCT mice was attributed to reduced myocardial deformation in the peri-infarct region (strain-%: 11.14±0.97 for WT, 15.34±1.10 for TFΔCT, p=0.007; strain rate-/s: 3.89±0.26 for WT, 5.18±0.21 for TFΔCT, p=0.0005). Histological analysis demonstrated that TFΔCT hearts had in the infarct area greater proliferation of endothelial cells and myofibroblasts accompanied with better scar formation. Compared with wild-type hearts, infarcted TFΔCT hearts showed less infiltration of proinflammatory cells with concomitant lower expression of protease-activated receptor-1 (PAR1)-Rac1 axis. Furthermore, infarcted TFΔCT hearts presented markedly higher peri-infarct vessel density associated with enhanced endothelial cell proliferation and higher expression of PAR2 and PAR2-associated pro-angiogenic pathway factors.

Conclusions

Our findings demonstrate that the TF cytoplasmic domain exacerbates post-infarct cardiac injury and adverse LV remodeling via differential regulation of inflammation and angiogenesis. Targeted inhibition of the TF cytoplasmic domain-mediated intracellular signaling may ameliorate post-infarct LV remodeling without perturbing coagulation.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): National University Health System of Singapore

Non-immune hydrops fetalis secondary to congenital chylothorax with diffuse interstitial lung disease: a diagnostic conundrum

A Chinese male infant was born at 35 weeks weighing 2935 g to a mother with polyhydramnios and prenatal hydrops fetalis. He developed marked respiratory distress secondary to bilateral congenital chylothorax and required pleural drainage, high frequency oscillation and inhaled nitric oxide therapy. He was extubated to non-invasive ventilation by day 14. There was no bacterial or intrauterine infection, haematologic, chromosomal or cardiac disorder. He was exclusively fed medium-chain triglyceride formula. High-resolution CT showed diffuse interstitial lung disease. He received a dexamethasone course for chronic lung disease to facilitate supplemental oxygen weaning. A multidisciplinary team comprising neonatology, pulmonology, haematology, interventional radiology and thoracic surgery considered congenital pulmonary lymphangiectasia as the most likely diagnosis and advised open lung biopsy, lymphangiography or scintigraphy for diagnostic confirmation should symptoms of chylothorax recur. Fortunately, he was weaned off oxygen at 5 months of life, and tolerated human milk challenge at 6 months of life and grew well.

Implementation of a nutrition screening tool to improve nutritional status of children with cancer in Singapore's largest paediatric hospital

Poor nutritional status in children with cancer can impact treatment outcomes and mortality. Nutrition screening is a simple yet effective approach to identify malnutrition risk for early intervention. We aim to improve the identification of children with cancer at high risk of malnutrition, so that nutritional intervention and rehabilitation can commence early for these children. Our multidisciplinary team conducted a root cause analysis and concluded that the generic screening tool did not differentiate malnutrition risk for different cancer types, stage and intensity of treatment. Hence, a screening tool that considered the identified factors was tested for reliability and validity first. Subsequently, we used the Plan, Do, Study, Act model with two improvement cycles to put in place a systematic process to facilitate the implementation. The interventions included (1) instituting the tool in the electronic medical records and (2) direct referral to dietitian based on screening score.

We compared pre- and post-implementation cohorts and demonstrated better identification of nutritionally at-risk patients (36.4%–85.7%, p<0.001) with the new tool as well as improved timeliness of nutritional intervention (3 days to 1 day from admission, p=0.010). A lower malnutrition rate (17.4%–6.5%, p<0.001) in the postimplementation cohort was also demonstrated. Nutritional intervention within 48 hours of admission led to an overall positive weight change at 3 months (+2.68%, IQR: −1.14 to 9.09 vs −0.43%, −6.60 to 2.29; p=0.036) in the malnourished patients from both cohorts. Further studies will be conducted to evaluate the scale of the effectiveness of early intervention and close nutritional monitoring, in improving the nutritional status of children with cancer. The collaborative partnership among the doctors, nurses and dietitians has helped to streamline and simplify nutrition screening, making it an efficient and sustainable system in our hospital.

Excellent Survival Outcomes of Pediatric Patients With Acute Myeloid Leukemia Treated With the MASPORE 2006 Protocol

PURPOSE

To determine the prognostic factors in pediatric patients with acute myeloid leukemia (AML) and to assess whether their outcomes have improved over time.

PATIENTS AND METHODS

Sixty-two patients with AML excluding acute promyelocytic leukemia were retrospectively analyzed. Patients in the earlier cohort (n = 36) were treated on the Medical Research Council (MRC) AML12 protocol, whereas those in the recent cohort (n = 26) were treated on the Malaysia-Singapore AML protocol (MASPORE 2006), which differed in terms of risk group stratification, cumulative anthracycline dose, and timing of hematopoietic stem-cell transplantation for high-risk patients.

RESULTS

Significant improvements in 10-year overall survival and event-free survival were observed in patients treated with the recent MASPORE 2006 protocol compared to the earlier MRC AML12 protocol (overall survival: 88.0% ± 6.5% vs 50.1% ± 8.6%, P = .002; event-free survival: 72.1% ± 9.0 vs 50.1% ± 8.6%, P = .045). In univariate analysis, patients in the recent cohort had significantly lower intensive care unit admission rate (11.5% vs 47.2%, P = .005) and numerically lower relapse rate (26.9% vs 50.0%, P = .068) compared to the earlier cohort. Multivariate analysis showed that treatment protocol was the only independent predictive factor for overall survival (hazard ratio = 0.21; 95% confidence interval, 0.06-0.73, P = .014).

CONCLUSION

Outcomes of pediatric AML patients have improved over time. The more recent MASPORE 2006 protocol led to significant improvement in long-term survival rates and reduction in intensive care unit admission rate.

Cardiotoxicity After Anthracycline Chemotherapy for Childhood Cancer in a Multiethnic Asian Population

Background: Anthracyclines are widely used to treat childhood cancers; however, they cause cardiotoxicity. To address the paucity of clinical data from Asian populations, this study investigated the epidemiology of pediatric anthracycline-induced cardiotoxicity, during and after chemotherapy, in a multiethnic Asian population. Procedure: This was a single-center, retrospective analysis of 458 anthracycline-treated pediatric oncology patients at KK Women's and Children's Hospital, a tertiary children's hospital in Singapore from 2005 through 2015. We investigated cardiotoxicity (defined as left ventricular fractional shortening <28% on echocardiography) and its risk factors using univariate logistic regression as well as survival estimates through the Kaplan-Meier method to compare survival distribution between patients with and without cardiotoxicity. Results: Over a follow-up period of almost 4 years, we found that 7% (32/458) of the cohort developed cardiotoxicity, with 37.5% (12/32) of these manifesting as clinical heart failure, whilst the rest were asymptomatic. The cardiotoxic cohort demonstrated a significantly higher mortality rate compared to the non-cardiotoxic group at 46.9 vs. 19.2% (p < 0.001), of whom 3 (9.4%) died from end-stage heart failure. We found that traditional predictors such as female sex, age at diagnosis, and cumulative doxorubicin equivalent dose were not predictors of cardiotoxicity. Conclusion: Our study reaffirms that freedom from symptoms does not ensure normal heart function and suggests that children with abnormal ventricular systolic function have higher mortality risk compared to those with normal systolic function. The findings contribute to improved understanding of the Asian burden to aid development of measures to prevent or reduce the risk of cardiotoxicity.

Neuroblastoma patient-derived cultures are enriched for a mesenchymal gene signature and reflect individual drug response

Ex vivo evaluation of personalized models can facilitate individualized treatment selection for patients, and advance the discovery of novel therapeutic options. However, for embryonal malignancies, representative primary cultures have been difficult to establish. We developed patient‐derived cell cultures (PDCs) from chemo‐naïve and post–treatment neuroblastoma tumors in a consistent and efficient manner, and characterized their in vitro growth dynamics, histomorphology, gene expression, and functional chemo‐response. From 34 neuroblastoma tumors, 22 engrafted in vitro to generate 31 individual PDC lines, with higher engraftment seen with metastatic tumors. PDCs displayed characteristic immunohistochemical staining patterns of PHOX2B, TH, and GD2 synthase. Concordance of MYCN amplification, 1p and 11q deletion between PDCs and patient tumors was 83.3%, 72.7%, and 80.0% respectively. PDCs displayed a predominantly mesenchymal‐type gene expression signature and showed upregulation of pro‐angiogenic factors that were similarly enriched in culture medium and paired patient serum samples. When tested with standard‐of‐care cytotoxics at human C_max‐equivalent concentrations, MYCN‐amplified and non‐MYCN‐amplified PDCs showed a differential response to cyclophosphamide and topotecan, which mirrored the corresponding patients’ responses, and correlated with gene signatures of chemosensitivity. In this translational proof‐of‐concept study, early‐phase neuroblastoma PDCs enriched for the mesenchymal cell subpopulation recapitulated the individual molecular and phenotypic profile of patient tumors, and highlighted their potential as a platform for individualized ex vivo drug‐response testing.

P5719Plasma proteomics identify plaque-related proteins that predict long-term recurrent coronary events in patients with acute coronary syndrome

Background

Coronary plaque burden and composition drive recurrent ischaemic events in coronary artery disease.

Purpose

We first investigated the association between plasma proteins and coronary plaque characteristics in a cohort of asymptomatic individuals with low-intermediate Framingham Risk Score. Plaque-related proteins were further evaluated in a second cohort of patients with acute coronary syndrome (ACS) to determine their prognostic value for predicting future myocardial infarction (MI).

Methods

We profiled 1305 plasma proteins using an aptamer-based array (SOMAscan) in asymptomatic individuals who had undergone 384-slice coronary computed tomography angiography. Plaques were categorized by composition as calcified or non-calcified. First, we identified proteins that were different (based on multiple testing adjusted p-values: q-value <0.05) between 250 ACS patients who suffered a recurrent MI event on follow-up compared with another 250 ACS patients who remained event-free using Mann-Whitney U test. Next, protein candidates that also correlated (Pearson's p<0.05) with specific categories of plaque composition were evaluated using a cox proportional hazards model to determine the risk of recurrent MI, adjusting for potential confounders in the second cohort.

Results

A total of 65 and 120 plasma proteins were significantly associated with calcified and non-calcified plaques respectively in the asymptomatic cohort (N=79). Of these 185 proteins, 23 proteins were differentially expressed (DE) between ACS patients with and without recurrent MI events (median follow-up 1811 days). The top three up-and down-regulated proteins in the recurrent MI group were macrophage-capping protein, trefoil factor 3 and cystatin-SN (median FC 1.22, 1.17 and 1.17; q-value 4.34x10–6, 2.18x10–4, 3.17x10–3 respectively) and fibroblast growth factor 20, lymphotoxin a2/b1 and vascular endothelial growth factor receptor 2 (median FC 0.92, 0.94 and −0.090; q-value 1.31x10–3, 9.45x10–3 and 3.90x10–3) respectively. The quartiles of these protein concentrations were also associated with risk of recurrent MI, (log-rank test p-value range from 2.71x10–7 to 0.04). Of the DE proteins, the adjusted hazards ratio (HR) of cystatin-SN in the highest quartile (Q4) was 1.44 times that of the first quartile (Q1) (adjusted HR: 1.44, 95% CI: 0.93–2.2) and higher plasma concentration of cystatin-SN was associated with increasing risk of recurrent MI events (Trend test p=0.004). On the other hand, the highest quartile of fibroblast growth factor 20 was associated with 44% reduction in risks of recurrent MI adjusted HR: 0.56, 95% CI of HR: 0.35–0.87), with significant trend test (p=0.0096).

Conclusions

Large-scale plasma proteomics identified novel plaque-related proteins predictive of recurrent coronary events in patients with ACS. Further studies may help unravel the biological underpinnings of these circulating proteins and their potential as novel prognostic biomarkers.

Acknowledgement/Funding

This work was supported by grant NMRC/CSA-INV/0001/2016 from the National Medical Research Council, Singapore.

P2582Signature of plasma extracellular vesicles associated proteins in acute myocardial infarction patients

Background

Prediction of left ventricular (LV) remodeling post-acute myocardial infarction (AMI) remains challenging. Several circulating biomarkers have been associated with post-AMI LV remodeling, however, there is no biomarker available to distinguish adverse versus reverse LV remodeling.

Purpose

In this study, we aimed to assess the association of extracellular vesicles (EVs) associated proteins with LV remodeling post-AMI.

Methods

Plasma EVs were isolated via precipitation with dextran sulphate as we previously reported. The protein levels of EV associated von Willebrand factor (VWF), SerpinC1 (antithrombin-III), plasminogen and SerpinF2 (alpha 2-antiplasmin) were determined in the citrate-anticoagulated plasma from 57 healthy subjects and 200 patients recruited in the Post-AMI Left Ventricular Remodeling Biomarker Analysis (PAMILA) study. Patients were categorized into two groups: adverse LV remodeling (n=100) characterized by an increase or reverse LV remodeling (n=100) characterized by a decrease, in LV end systolic volume by ≥15% over 6 months. Patients' plasma was collected at baseline (within 3 days after percutaneous coronary intervention), 1 month and 6 months post-AMI. Log transformation of EV protein levels was performed for assessment in a multiple multi-level longitudinal data analysis with structural equation model (with level of significance fixed at 0.05).

Results

Compared to healthy subjects, baseline protein levels of EV associated VWF and SerpinF2 were significantly higher in post-AMI patients, whereas no difference was observed in SerpinC1 and plasminogen. Among the patients, those on statins (196 out of 200 patients) showed lower protein levels of EV associated VWF (p<0.001) and plasminogen (p=0.003), whereas patients treated with P2Y12 platelet inhibitors (195 out of 200 patients) showed higher protein levels of EV associated VWF (p=0.003) and plasminogen (p=0.035). Multiple multi-level longitudinal data analysis with structural equation model showed that protein levels of EV associated VWF (p<0.001) and SerpinC1 (p=0.021) were lower in patients with adverse LV remodeling than that in patients with reverse LV remodeling during the 6-month follow-up post-AMI. In contrast, protein levels of EV associated plasminogen (p=0.002) and SerpinF2 (p=0.002) were higher in patients with adverse LV remodeling. The differences in the four EV associated proteins between patients with adverse versus reverse LV remodeling remain significant after adjusting for age, gender, ethnicity, medications, lipid profile and risk factors (diabetes, hypertension, dyslipidemia and smoking).

Conclusions

Lower levels of EV associated coagulation proteins (VWF and SerpinC1) and higher levels of EV associated fibrinolytic proteins (plasminogen and SerpinF2) were presented in patients with adverse LV remodeling compared to those with reverse LV remodeling post-AMI.

Acknowledgement/Funding

National University Health System Singapore (NUHS O-CRG 2016 Oct-23) to JW Wang

2110. Taurolidine-Citrate Lock Solution for the Prevention of Central-Line-associated Bloodstream Infection (CLABSI) in Pediatric Hematology-Oncology and Gastrointestinal Failure Patients with High Baseline CLABSI Rates

Background

Methods

Results

Conclusion

Disclosures

Clinical relevance of screening checklists for detecting cancer predisposition syndromes in Asian childhood tumours

Assessment of cancer predisposition syndromes (CPS) in childhood tumours is challenging to paediatric oncologists due to inconsistent recognizable clinical phenotypes and family histories, especially in cohorts with unknown prevalence of germline mutations. Screening checklists were developed to facilitate CPS detection in paediatric patients; however, their clinical value have yet been validated. Our study aims to assess the utility of clinical screening checklists validated by genetic sequencing in an Asian cohort of childhood tumours. We evaluated 102 patients under age 18 years recruited over a period of 31 months. Patient records were reviewed against two published checklists and germline mutations in 100 cancer-associated genes were profiled through a combination of whole-exome sequencing and multiplex ligation-dependent probe amplification on blood-derived genomic DNA. Pathogenic germline mutations were identified in ten (10%) patients across six known cancer predisposition genes: TP53, DICER1, NF1, FH, SDHD and VHL. Fifty-four (53%) patients screened positive on both checklists, including all ten pathogenic germline carriers. TP53 was most frequently mutated, affecting five children with adrenocortical carcinoma, sarcomas and diffuse astrocytoma. Disparity in prevalence of germline mutations across tumour types suggested variable genetic susceptibility and implied potential contribution of novel susceptibility genes. Only five (50%) children with pathogenic germline mutations had a family history of cancer. We conclude that CPS screening checklists are adequately sensitive to detect at-risk children and are relevant for clinical application. In addition, our study showed that 10% of Asian paediatric solid tumours have a heritable component, consistent with other populations.

Can Bedside Ultrasonography of Internal Jugular Vein Replace Ultrasonography of Inferior Vena Cava for Volume Status Estimation?

Introduction

Estimation of haemodynamic status of acute and critically ill patients at Accident & Emergency (A&E) Departments is important. Measurement of inferior vena cava (IVC) diameter and collapsibility index by bedside ultrasound (USG) was known to correlate well with volume status of these patients. However, the value of similar estimation based on USG measurement of internal jugular vein (IJV) diameter was seldom studied. Whether USG measurement of IJV diameter can replace that of IVC diameter was unknown.

Methods

This was a cross-sectional study using a convenience sample of healthy volunteers among staff of a local A&E. The diameter of IJV and IVC (IJVD and IVCD) of the 51 participants were measured by bedside USG. The corresponding collapsibility index (CI) of IJV and IVC were then calculated. The correlation between IJVD and IVCD was assessed by the use of Bland-Altman plot.

Results

Median value of IVC-CI and of IJV-CI was 29.41% and 17.12% respectively. The mean of the difference of measurement of IJV-CI and IVC-CI was −11.10% (95% Confidence Interval: −15.27 to −6.92). The limits of agreement of the above difference were −40.77% and 18.58%. The range of these limits was too wide.

Conclusion

Because the range of limits of agreement between IJV-CI and IVC-CI were too wide, IJV-CI may not be used as an alternative to IVC-CI for the estimation of the volume status of normal adults.

Health claims on food products in Southeast Asia: regulatory frameworks, barriers, and opportunities

The Association of Southeast Asian Nations aims to act as a single market and allow free movement of goods, services, and manpower. The purpose of this article is to present an overview of the current regulatory framework for health claims in Southeast Asia and to highlight the current barriers and opportunities in the regulatory frameworks in the Association of Southeast Asian Nations. To date, 5 countries in Southeast Asia, i.e., Indonesia, Malaysia, the Philippines, Singapore, and Thailand, have regulations and guidelines to permit the use of health claims on food products. There are inconsistencies in the regulations and the types of evidence required for health claim applications in these countries. A clear understanding of the regulatory frameworks in these countries may help to increase trade in this fast-growing region and to provide direction for the food industry and the regulatory community to develop and market food products with better nutritional quality tailored to the needs of Southeast Asian consumers.

Second neoplasms in survivors of childhood acute lymphoblastic leukemia treated with both chemotherapy and radiotherapy

e293

Background: Second malignant neoplasms (SMNs) are a concern in survivors of childhood cancer. Chemotherapy forms the mainstay of treatment for acute lymphoblastic leukaemia, but radiotherapy is used in certain situations. As both chemotherapy and radiotherapy can be carcinogenic, patients treated with both modalities may be at a higher risk of SMNs. This study aims to investigate the incidence of SMNs in patients treated with both chemotherapy and radiotherapy. Methods: Children aged 16 years and below diagnosed with acute lymphoblastic leukaemia from 1993 to 2014 were identified in the Childhood Cancer Registry. Manual and electronic medical records were reviewed for information on demographics, management and SMNs. Results: A total of 64 patients treated with both chemotherapy and radiotherapy were identified. Seventeen (26.6%) were female and 47 (73.4%) were male. The median follow-up was 9.2 years (range, 1.1-22.0 years). The median age at diagnosis was 5.3 years, (range, 0.3-14.6 years). The median age at which radiotherapy was given was 6.6 years (range, 2.9-15.4 years). SMNs were noted in 3 of 64 (4.7%) patients. Two of 3 patients had a SMN within the radiation field (both cranial). The histological diagnoses were basal cell carcinoma and cerebral PNET. The remaining patient had an ovarian immature teratoma outside the radiation field. The latency period ranged from 8.3 years to 13.3 years (median 9.4 years) from date of diagnosis to development of SMN. The estimated 10-year cumulative incidence was 4.3%, 95% CI [0.01, 0.13] using a competing risks analysis. Radiotherapy data was available in 63 patients. Fifty-one of 63 (81.0%) received cranial irradiation, of which 3 (5.9%) also received spinal irradiation. Total body irradiation was performed in 20 of 63 (31.7%), and testicular irradiation in 17 of 63 (27.0%) patients. The orbit was targeted in 3 of 63 (4.8%) patients. Conclusions: Long term survivors of acute lymphoblastic leukaemia treated with both chemotherapy and radiotherapy may have a significant risk of second malignant neoplasms, which may occur years after the initial diagnosis.

Acute carbon monoxide poisoning in a regional hospital in Hong Kong: historical cohort study

OBJECTIVES

This study aimed to describe the clinical profiles of all patients with carbon monoxide poisoning admitted to a regional hospital in order to enhance the vigilance of health care professionals for delayed neurological sequelae associated with carbon monoxide poisoning and to identify the prognostic factors associated with their development. This study also aimed to assess the impact of hyperbaric oxygen therapy on the development of delayed neurological sequelae in these patients.

METHODS

This was a historical cohort study in which all patients with a diagnosis of carbon monoxide poisoning managed in a regional hospital in Hong Kong from 12 February 2003 to 8 November 2013 were recruited. Main outcome measures included delayed neurological sequelae.

RESULTS

Of the clinical profiles of 93 patients analysed, 24 patients received hyperbaric oxygen therapy and did not develop delayed neurological sequelae. Seven patients who did not receive hyperbaric oxygen therapy developed delayed neurological sequelae. Comparison of groups with and without delayed neurological sequelae (excluding hyperbaric oxygen therapy-treated patients) revealed that loss of consciousness (P=0.038), Glasgow Coma Scale score of 3 (P=0.012), elevated troponin level (P<0.001), higher creatine kinase level (P=0.008), and intubation requirement (P=0.007) were possible prognostic factors for the development of delayed neurological sequelae.

CONCLUSION

Although not statistically significant, this study showed a 100% protective effect of hyperbaric oxygen therapy against development of severe delayed neurological sequelae in patients with severe carbon monoxide poisoning. Further study with better study design is warranted. Loss of consciousness, low Glasgow Coma Scale score, intubation requirement, elevated troponin and higher creatine kinase levels were possible prognostic factors for development of delayed neurological sequelae in patients with severe carbon monoxide poisoning. A well-defined treatment protocol, appropriate follow-up duration and neuropsychiatric tests together with a hospital-based hyperbaric chamber are recommended for management of patients with severe carbon monoxide poisoning.

Causative Pathogens of Febrile Neutropaenia in Children Treated for Acute Lymphoblastic Leukaemia

INTRODUCTION

Treatment of acute lymphoblastic leukaemia (ALL) using intensive chemotherapy has resulted in high cure rates but also substantial morbidity. Infective complications represent a significant proportion of treatment-related toxicity. The objective of this study was to describe the microbiological aetiology and clinical outcome of episodes of chemotherapy-induced febrile neutropaenia in a cohort of children treated for ALL at our institution.

MATERIALS AND METHODS

Patients with ALL were treated with either the HKSGALL93 or the Malaysia-Singapore (Ma-Spore) 2003 chemotherapy protocols. The records of 197 patients who completed the intensive phase of treatment, defined as the period of treatment from induction, central nervous system (CNS)-directed therapy to reinduction from June 2000 to January 2010 were retrospectively reviewed.

RESULTS

There were a total of 587 episodes of febrile neutropaenia in 197 patients, translating to an overall rate of 2.98 episodes per patient. A causative pathogen was isolated in 22.7% of episodes. An equal proportion of Gram-positive bacteria (36.4%) and Gram-negative bacteria (36.4%) were most frequently isolated followed by viral pathogens (17.4%), fungal pathogens (8.4%) and other bacteria (1.2%). Fungal organisms accounted for a higher proportion of clinically severe episodes of febrile neutropaenia requiring admission to the high-dependency or intensive care unit (23.1%). The overall mortality rate from all episodes was 1.5%.

CONCLUSION

Febrile neutropaenia continues to be of concern in ALL patients undergoing intensive chemotherapy. The majority of episodes will not have an identifiable causative organism. Gram-positive bacteria and Gram-negative bacteria were the most common causative pathogens identified. With appropriate antimicrobial therapy and supportive management, the overall risk of mortality from febrile neutropaenia is extremely low.

Neuroblastoma in Children Under 12 Months in Singapore--15-Year Experience and Outcomes From KKH

BACKGROUND

Expectant observation of small adrenal lesions has shown promising results in recent studies. We present our 15 years outcome of managing infant neuroblastoma.

METHODS

All patients with neuroblastoma below the age of 1 year treated at the largest pediatric hospital in Singapore between 1998 and 2012 were identified.

RESULTS

Twenty-two patients were included in our study. Six were antenatally diagnosed. Nineteen (86%) patients had surgical resection of the tumor. Eight (36%) patients received chemotherapy as part of their treatment. Six patients were observed three of which had large adrenal tumors. Median follow-up in our series was 2.6 years. The 5 year overall survival was 90%. There were no recurrences and there were 2 deaths in our series.

CONCLUSION

Our series shows excellent outcomes of infant neuroblastoma at our center. Careful observation of large tumors may be an option to avoid the morbidity of surgery.

Fasxiator, a novel factor XIa inhibitor from snake venom, and its site-specific mutagenesis to improve potency and selectivity

BACKGROUND

Bleeding remains a major limitation of standard anticoagulant drugs that target the extrinsic and common coagulation pathways. Recently, intrinsic coagulation factors are increasingly being investigated as alternative targets for developing anticoagulant drugs with lower bleeding risk.

OBJECTIVES

Goals were to (i) identify novel anticoagulants selectively targeting intrinsic coagulation pathway and (ii) characterize and further improve the properties of the identified anticoagulants.

METHODS AND RESULTS

We have isolated and sequenced a specific factor XIa (FXIa) inhibitor, henceforth named Fasxiator, from the venom of the banded krait snake, Bungarus fasciatus. It is a Kunitz-type protease inhibitor that prolonged activated partial thromboplastin time without significant effects on prothrombin time. Fasxiator was recombinantly expressed (rFasxiator), purified, and characterized to be a slow-type inhibitor of FXIa that exerts its anticoagulant activities (doubled activated partial thromboplastin time at ~ 3 μmol L(-1) ) by selectively inhibiting human FXIa in in vitro assays. A series of mutants were subsequently generated to improve the potency and selectivity of recombinant rFasxiator. rFasxiatorN17R,L19E showed the best balance between potency (IC50 ~ 1 nmol L(-1) ) and selectivity (> 100 times). rFasxiatorN17R,L19E is a competitive slow-type inhibitor of FXIa (Ki  = 0.86 nmol L(-1) ), possesses anticoagulant activity that is ~ 10 times stronger in human plasma than in murine plasma, and prolonged the occlusion time of mice carotid artery in FeCl3 -induced thrombosis models.

CONCLUSION

We have isolated an exogenous FXIa specific inhibitor, engineered it to improve its potency by ~ 1000 times and demonstrated its in vitro and in vivo efficacy. These proof-of-principle data supported the further development of Fasxiator as a novel anticoagulant candidate.

Quantitative ultrasound and fracture risk prediction in non-osteoporotic men and women as defined by WHO criteria

This study sought to determine the association between calcaneal quantitative ultrasound (QUS) and fracture risk in individuals without osteoporosis according to the World Health Organization criteria (i.e., BMD T-score > -2.5). We found that calcaneal QUS is an independent predictor of fracture risk in women with non-osteoporotic bone mineral density (BMD).

INTRODUCTION

More than 50 % of women and 70 % of men who sustain a fragility fracture have BMD above the osteoporotic threshold (T-score > -2.5). Calcaneal QUS is associated with fracture risk. This study aimed to test the hypothesis that low calcaneal QUS is associated with increased fracture risk in individuals with non-osteoporotic BMD.

METHODS

We included 312 women and 390 men aged 62-90 years with BMD T-score > -2.5 at femoral neck. QUS was measured in broadband ultrasound attenuation (BUA) at the calcaneus using a CUBA sonometer. BMD was measured at the femoral neck (FNBMD) by dual energy X-ray absorptiometry using GE Lunar DPX-L densitometer. The incidences of any fragility fracture were ascertained by X-ray reports during the follow-up period from 1994 to 2011.

RESULTS

Of the 702 participants, 26 % of women (n = 80/312) and 14 % of men (n = 53/390) experienced at least one fragility fracture during the follow-up period. In women, after adjusting for covariates, increased risk of any fracture was significantly associated with decreased BUA (HR = 1.50; 95 % CI, 1.13-1.99). Compared with that of FNBMD, the models with BUA, in women, had greater AUC (0.71, 0.85, 0.71 for any, hip and vertebral fracture, respectively), and yielded a net reclassification improvement of 16.4 % (P = 0.009) when combined with FNBMD. In men, BUA was not significantly associated with fracture risk before and after adjustment.

CONCLUSION

These results suggest that calcaneal BUA is an independent predictor of fracture risk in women with non-osteoporotic BMD.

Hemophagocytic lymphohistiocytosis with isolated central nervous system reactivation and optic nerve involvement

Hemophagocytic lymphohistiocytosis is a rare childhood disorder characterized by uncontrolled proliferation of benign lymphocytes and histiocytes in multiple organs. Neurological presentations of central nervous system involvement are highly variable. The authors present a case of familial hemophagocytic lymphohistiocytosis in an 8-month-old girl with isolated central nervous system reactivation and optic nerve involvement. She presented with fever and hepatosplenomegaly at 2 months of age. Genetic studies confirmed familial hemophagocytic lymphohistiocytosis. There were no clinical features of central nervous system involvement at presentation. While on maintenance chemotherapy awaiting bone marrow transplant, she presented with new-onset seizures. Magnetic resonance imaging of the brain revealed extensive areas of abnormal signal and a thickened and enhancing left optic nerve. Ocular manifestations of hemophagocytic lymphohistiocytosis have rarely been described. To the authors' knowledge, this is the first case report of magnetic resonance imaging findings of optic nerve involvement in a child with hemophagocytic lymphohistiocytosis.

Random blinded rechecking of sputum acid-fast bacilli smear using fluorescence microscopy: 8 years' experience

BACKGROUND

The Hong Kong TB Reference Laboratory is a high volume laboratory examining around 400 sputum acid-fast bacilli smears daily using fluorescence microscopy (FM).

OBJECTIVE

To assess the effectiveness of blinded rechecking applied to FM in a high-throughput laboratory.

METHOD

From 2003, 2.5% (5% in 2003 and 2004) of all smears were randomly selected, relabelled and assigned to each technician (rechecker) in turn. These smears were restained and re-examined. Discordance between initial screener and rechecker was resolved by a controller.

RESULTS

From 2003 to 2010, low false-negative (LFN) errors (0.10-0.27%) were within the critical values, at 85% (1 year) and 90% (7 years) sensitivity. However, LFN error (0.28-0.62%) among recheckers was prominent. There were also low false-positive (LFP) cases (0.13-0.75%), but subsequent cultures showed these to be mycobacteria culture-positive. This relatively poor performance among the recheckers might be due to background fluorescence increase after restaining and/or inefficiency of the rechecking procedure.

CONCLUSION

In a high-throughput laboratory, blind rechecking is a good means of quality assurance. To minimise false LFP, problems due to restaining should be resolved before blinded rechecking can be generally applied in the field for FM where mycobacterial cultures are not routinely performed.

Minimal Residual Disease–Guided Treatment Deintensification for Children With Acute Lymphoblastic Leukemia: Results From the Malaysia-Singapore Acute Lymphoblastic Leukemia 2003 Study

Purpose

To improve treatment outcome for childhood acute lymphoblastic leukemia (ALL), we designed the Malaysia-Singapore ALL 2003 study with treatment stratification based on presenting clinical and genetic features and minimal residual disease (MRD) levels measured by polymerase chain reaction targeting a single antigen-receptor gene rearrangement.

Patients and Methods

Five hundred fifty-six patients received risk-adapted therapy with a modified Berlin-Frankfurt-Münster–ALL treatment. High-risk ALL was defined by MRD ≥ 1 × 10−3 at week 12 and/or poor prednisolone response, BCR-ABL1, MLL gene rearrangements, hypodiploid less than 45 chromosomes, or induction failure; standard-risk ALL was defined by MRD ≤ 1 × 10−4 at weeks 5 and 12 and no extramedullary involvement or high-risk features. Intermediate-risk ALL included all remaining patients.

Results

Patients who lacked high-risk presenting features (85.7%) received remission induction therapy with dexamethasone, vincristine, and asparaginase, without anthracyclines. Six-year event-free survival (EFS) was 80.6% ± 3.5%; overall survival was 88.4% ± 3.1%. Standard-risk patients (n = 172; 31%) received significantly deintensified subsequent therapy without compromising EFS (93.2% ± 4.1%). High-risk patients (n = 101; 18%) had the worst EFS (51.8% ± 10%); EFS was 83.6% ± 4.9% in intermediate-risk patients (n = 283; 51%).

Conclusion

Our results demonstrate significant progress over previous trials in the region. Three-drug remission-induction therapy combined with MRD-based risk stratification to identify poor responders is an effective strategy for childhood ALL.

The Hidden Impact of Childhood Cancer on the Family: A Multi-Institutional Study from Singapore

Introduction: The care of children with cancer creates emotional and financial hardships for their families. There is a lack of information on the impact of childhood cancer on the family as a whole in Singapore. Thus, we set out to assess the financial impact as well as its psychosocial impact in our local context. Materials and Methods: All patients diagnosed and treated for cancer at the Departments of Paediatrics, KK Women’s and Children’s Hospital and National University Hospital, Singapore were eligible for this study. Families of these patients completed 2 self-administered questionnaires: (i) About-you and your-family and (ii) the Impact-On-Family scale. For the latter, the total score was obtained by the summation of all scores, where high scores correlated to high impact. Results: Seventy-nine parents were enrolled during the study period from October 2008 to February 2009. Being of Malay/Indian origin was associated with a high overall family burden. On the other hand, being of Malay/Indian origin was also associated with most successful at mastery when a child was diagnosed with cancer (P = 0.001). In addition, when compared to caregivers who remained employed, those who were asked to quit their job, experienced a higher Financial Burden (P = 0.03), a high Familial/Social Burden (P = 0.05) and a high Personal Strain (P = 0.03). Conclusion: Childhood cancer impacted family life in Singapore at many levels. In particular, the factors involved are various cultural discourses; employment status of caregivers; and those whose leave/pay are affected. Key words: Burden, Cancer, Psychosocial

The hidden impact of childhood cancer on the family: a multi-institutional study from Singapore

INTRODUCTION

The care of children with cancer creates emotional and financial hardships for their families. There is a lack of information on the impact of childhood cancer on the family as a whole in Singapore. Thus, we set out to assess the financial impact as well as its psychosocial impact in our local context.

MATERIALS AND METHODS

All patients diagnosed and treated for cancer at the Departments of Paediatrics, KK Women's and Children's Hospital and National University Hospital, Singapore were eligible for this study. Families of these patients completed 2 self-administered questionnaires: (i) About-you and your-family and (ii) the Impact-On-Family scale. For the latter, the total score was obtained by the summation of all scores, where high scores correlated to high impact.

RESULTS

Seventy-nine parents were enrolled during the study period from October 2008 to February 2009. Being of Malay/Indian origin was associated with a high overall family burden. On the other hand, being of Malay/Indian origin was also associated with most successful at mastery when a child was diagnosed with cancer (P = 0.001). In addition, when compared to caregivers who remained employed, those who were asked to quit their job, experienced a higher Financial Burden (P = 0.03), a high Familial/Social Burden (P = 0.05) and a high Personal Strain (P = 0.03).

CONCLUSION

Childhood cancer impacted family life in Singapore at many levels. In particular, the factors involved are various cultural discourses; employment status of caregivers; and those whose leave/pay are affected.

Do children die? A retrospective review of deaths in a children's hospital

INTRODUCTION

We present a profile of deaths over two years in the medical departments of a children's hospital. The findings would help us better understand the individual dying experience of these patients. Service gaps and ways to optimise provision of supportive care were identified in the process.

METHODS

The inpatient notes of all children who died in the medical wards, including intensive care unit, were traced and reviewed by the investigators. Demographic data, diagnoses, length of stay and the care received were recorded.

RESULTS

A total of 68 children died in the two years. They were representative of all deaths nationally in terms of diagnoses. Two-thirds of the children died in the intensive care unit after having stayed there for an average of five days. All but one patient had invasive ventilation till they died. Eight out of every ten cases were assessed to be actively dying while being cared for. Most had 'Do-Not-Resuscitate' status in place, but few had been offered the option to choose the place of care or death when it became clear that they would not survive.

CONCLUSION

More efforts could be made to improve the care of dying children and their families. The Paediatric Palliative Service could assist in advance care planning at the end of life.

Use of deferiprone for iron chelation in patients with transfusion-dependent thalassaemia

AIM

To conduct a retrospective case analysis of the clinical efficacy and adverse effects of deferiprone in our population.

METHODS

All patients with transfusion-dependent thalassaemia at KK Hospital who have been on deferiprone were included in the study. Outcomes measured include the change in ferritin levels and cardiac T2* values during deferiprone therapy, and incidence of side effects.

RESULTS

Thirty-three (47.1%) of the total cohort of 70 patients have been on deferiprone, out of which 26 were on combination therapy with desferrioxamine. Majority of the patients (76%) had stable cardiac iron load during deferiprone therapy, and four patients with moderate to severe cardiac iron load showed improvement. Ten patients (30.3%) had improvement in their ferritin levels. Three patients (9.1%) developed mild neutropenia at 3, 18 and 26 months, respectively, and two patients (6.1%) had agranulocytosis at 4 and 10 months, respectively. Their neutrophil counts improved spontaneously after cessation of deferiprone. Thrombocytopenia developed in 27.3% of the patients and was transient in majority (77.8%) of the patients. Five patients (15.2%) developed arthritis that improved after cessation of deferiprone therapy, and one patient had transient arthralgia that resolved spontaneously. Three patients (9.1%) had nausea and abdominal pain.

CONCLUSION

Deferiprone effectively reduced or stabilised cardiac iron load in our patients. Thrombocytopenia, arthropathy, neutropenia and agranulocytosis are the most important side effects. It is recommended that patients on deferiprone have their full blood counts monitored weekly for the first year of therapy and subsequently fortnightly as long as they are on deferiprone.