Point-of-care high-sensitivity cardiac troponin in suspected acute myocardial infarction assessed at baseline and 2 h

BACKGROUND AND AIMS

Strategies to assess patients with suspected acute myocardial infarction (AMI) using a point-of-care (POC) high-sensitivity cardiac troponin I (hs-cTnI) assay may expedite emergency care. A 2-h POC hs-cTnI strategy for emergency patients with suspected AMI was derived and validated.

METHODS

In two international, multi-centre, prospective, observational studies of adult emergency patients (1486 derivation cohort and 1796 validation cohort) with suspected AMI, hs-cTnI (Siemens Atellica® VTLi) was measured at admission and 2 h later. Adjudicated final diagnoses utilized the hs-cTn assay in clinical use. A risk stratification algorithm was derived and validated. The primary diagnostic outcome was index AMI (Types 1 and 2). The primary safety outcome was 30-day major adverse cardiac events incorporating AMI and cardiac death.

RESULTS

Overall, 81 (5.5%) and 88 (4.9%) patients in the derivation and validation cohorts, respectively, had AMI. The 2-h algorithm defined 66.1% as low risk with a sensitivity of 98.8% [95% confidence interval (CI) 89.3%-99.9%] and a negative predictive value of 99.9 (95% CI 99.2%-100%) for index AMI in the derivation cohort. In the validation cohort, 53.3% were low risk with a sensitivity of 98.9% (95% CI 92.4%-99.8%) and a negative predictive value of 99.9% (95% CI 99.3%-100%) for index AMI. The high-risk metrics identified 5.4% of patients with a specificity of 98.5% (95% CI 96.6%-99.4%) and a positive predictive value of 74.5% (95% CI 62.7%-83.6%) for index AMI.

CONCLUSIONS

A 2-h algorithm using a POC hs-cTnI concentration enables safe and efficient risk assessment of patients with suspected AMI. The short turnaround time of POC testing may support significant efficiencies in the management of the large proportion of emergency patients with suspected AMI.

The Impact of an Accelerated Diagnostic Protocol Using Conventional Troponin I for Patients With Cardiac Chest Pain in the Emergency Department

Background

This study strove to assess the impact of the implementation of an accelerated diagnostic protocol (ADP), using shortened serial-testing intervals and a conventional troponin I (c-TnI) test, on emergency department (ED) length of stay (LOS).

Methods

This retrospective cohort study included adults (aged ≥ 18 years) presenting to a Canadian ED with a primary complaint of cardiac chest pain between January 14, 2017 and January 15, 2019. For non-high-risk patients, the troponin delta timing decreased from 6 hours to 3 hours, and a different conventional troponin I level cut-point was implemented on January 15, 2018. The primary outcome was ED LOS. Secondary outcomes included disposition status, consultation proportions, and major adverse cardiac events within 30 days.

Results

A total of 3133 patient interactions were included. Although the overall decrease in median ED LOS was not significant (P = 0.074), a significant reduction occurred in ED LOS (-33 minutes; 95% confidence interval: -53.6 to -12.4 minutes) among patients who were discharged in the post-ADP group. Consultations were unchanged between groups (36.1% before vs 33.8% after; P = 0.17). The major adverse cardiac events outcomes were unchanged across cohorts (15.9% vs 15.3%; P = 0.62).

Conclusions

The implementation of an ADP, with a conventional troponin I test, for cardiac chest pain in a Canadian ED was not associated with a significant reduction of LOS for all patients; however, a significant reduction occurred for patients who were discharged, and the strategy appears safe.

A streamlined Emergency Department approach to moderate risk chest pain in patients with no pre-existing coronary artery disease: A pilot study

OBJECTIVE

Moderate risk patients with chest pain and no previously diagnosed coronary artery disease (CAD) who present to ED require further risk stratification. We hypothesise that management of these patients by ED physicians can decrease length of stay (LOS), without increasing patient harm.

METHODS

A prospective pilot study with comparison to a pre-intervention control group was performed on patients presenting with chest pain to an ED in Perth, Australia between May and October 2021, following the introduction of a streamlined guideline consisting of ED led decision making and early follow up. Patients had no documented CAD and were at moderate risk of major adverse cardiac events (MACE). Electronic data was used for comparison. Primary outcomes were total LOS and LOS following troponin.

RESULTS

One hundred eighty-six patients were included. Median total LOS was reduced by 62 min, but this change was not statistically significant (482 [360-795] vs 420 [360-525] min, P = 0.06). However, a significant 60 min decrease in LOS was found following the final troponin (240 (120-571) vs 180 (135-270) min, P = 0.02). There was no difference in the rate of MACE (0% vs 2%, P = 0.50), with no myocardial infarction or death.

CONCLUSIONS

Our study suggests that patients with no pre-existing CAD can be safely managed by emergency physicians streamlining their ED management and decreasing LOS. This pathway could be used in other centres following confirmation of the results by a larger study.

A Single High-Sensitivity Cardiac Troponin T Strategy for Ruling Out Myocardial Infarction

Background

Ruling out acute myocardial infarction (AMI) in the emergency department (ED) is challenging. Studies have shown that a high-sensitivity cardiac troponin T (hs-cTnT) <5 ng/L or <6 ng/L at presentation (0 h) can be used to rule out AMI. The objective of this study was to identify whether an even higher hs-cTnT threshold can be used for a safe rule out of AMI in the ED.

Methods

The derivation cohort consisted of 24,973 ED patients with a primary complaint of chest pain. In this cohort, we identified the highest concentration of 0 h hs-cTnT that corresponded to a negative predictive value (NPV) of ≥99.5% for the primary endpoint of AMI/all-cause death within 30 days and the secondary endpoint of all-cause death within one year. The results were validated in two cohorts consisting of 132,021 and 1167 ED chest pain patients.

Results

The 0 h hs-cTnT threshold corresponding to a NPV of ≥99.5% for the primary endpoint was <9 ng/L (NPV: 99.6% and 95% CI: 99.5-99.7). This cutoff provided a sensitivity of 96.2% (95% CI: 95.2-97.1) and identified 59.7% of the patients as low risk compared to 35.8% and 43.9% with a 0 h hs-cTnT <5 ng/L and <6 ng/L, respectively. The results were similar in the validation cohorts and seemed to perform even better in patients where the 0 h hs-cTnT was measured >3 h after symptom onset and in those with a nonischemic ECG and nonhigh risk history.

Conclusions

A 0 h hs-cTnT cutoff of <9 ng/L safely rules out AMI/death within 30 days in a majority of chest pain patients and is a more effective strategy than the currently recommended <5 ng/L and <6 ng/L cutoffs. This trial is registered with NCT03421873.

Prior electrocardiograms not useful for machine learning predictions of major adverse cardiac events in emergency department chest pain patients

At the emergency department (ED), it is important to quickly and accurately determine which patients are likely to have a major adverse cardiac event (MACE). Machine learning (ML) models can be used to aid physicians in detecting MACE, and improving the performance of such models is an active area of research. In this study, we sought to determine if ML models can be improved by including a prior electrocardiogram (ECG) from each patient. To that end, we trained several models to predict MACE within 30 days, both with and without prior ECGs, using data collected from 19,499 consecutive patients with chest pain, from five EDs in southern Sweden, between the years 2017 and 2018. Our results indicate no improvement in AUC from prior ECGs. This was consistent across models, both with and without additional clinical input variables, for different patient subgroups, and for different subsets of the outcome. While contradicting current best practices for manual ECG analysis, the results are positive in the sense that ML models with fewer inputs are more easily and widely applicable in practice.

Rapid access chest pain clinics in Australia and New Zealand

Chest pain is the second most common reason for adult emergency department presentations. Most patients have low or intermediate risk chest pain, which historically has led to inpatient admission for further evaluation. Rapid access chest pain clinics represent an innovative outpatient pathway for these low and intermediate risk patients, and have been shown to be safe and reduce hospital costs. Despite variations in rapid access chest pain clinic models, there are limited data to determine the most effective approach. Developing a national framework could be beneficial to provide sites with evidence, possible models, and business cases. Multicentre data analysis could enhance understanding and monitoring of the service.

Variation in Health Care Processes, Quality and Outcomes According to Day and Time of Chest Pain Presentation via Ambulance

BACKGROUND

Previous studies examining temporal variations in cardiovascular care have largely been limited to assessing weekend and after-hours effects. We aimed to determine whether more complex temporal variation patterns might exist in chest pain care.

METHODS

This was a population-based study of consecutive adult patients attended by emergency medical services (EMS) for non-traumatic chest pain without ST elevation in Victoria, Australia between 1 January 2015 and 30 June 2019. Multivariable models were used to assess whether time of day and week stratified into 168 hourly time periods was associated with care processes and outcomes.

RESULTS

There were 196,365 EMS chest pain attendances; mean age 62.4 years (standard deviation [SD] 18.3) and 51% females. Presentations demonstrated a diurnal pattern, a Monday-Sunday gradient (Monday peak) and a reverse weekend effect (lower rates on weekends). Five temporal patterns were observed for care quality and process measures, including a diurnal pattern (longer emergency department [ED] length of stay), an after-hours pattern (lower angiography or transfer for myocardial infarction, pre-hospital aspirin administration), a weekend effect (shorter ED clinician review, shorter EMS off-load time), an afternoon/evening peak period pattern (longer ED clinician review, longer EMS off-load time) and a Monday-Sunday gradient (ED clinician review, EMS offload time). Risk of 30-day mortality was associated with weekend presentation (Odds ratio [OR] 1.15, p=0.001) and morning presentation (OR 1.17, p<0.001) while risk of 30-day EMS reattendance was associated with peak period (OR 1.16, p<0.001) and weekend presentation (OR 1.07, p<0.001).

CONCLUSIONS

Chest pain care demonstrates complex temporal variation beyond the already established weekend and after-hours effect. Such relationships should be considered during resource allocation and quality improvement programs to improve care across all days and times of the week.

Healthcare cost burden of acute chest pain presentations

BACKGROUND

This study aimed to estimate the direct healthcare cost burden of acute chest pain attendances presenting to ambulance in Victoria, Australia, and to identify key cost drivers especially among low-risk patients.

METHODS

State-wide population-based cohort study of consecutive adult patients attended by ambulance for acute chest pain with individual linkage to emergency and hospital admission data in Victoria, Australia (1 January 2015-30 June 2019). Direct healthcare costs, adjusted for inflation to 2020-2021 ($A), were estimated for each component of care using a casemix funding method.

RESULTS

From 241 627 ambulance attendances for chest pain during the study period, mean chest pain episode cost was $6284, and total annual costs were estimated at $337.4 million ($68 per capita per annum). Total annual costs increased across the period ($310.5 million in 2015 vs $384.5 million in 2019), while mean episode costs remained stable. Cardiovascular conditions (25% of presentations) were the most expensive (mean $11 523, total annual $148.7 million), while a non-specific pain diagnosis (49% of presentations) was the least expensive (mean $3836, total annual $93.4 million). Patients classified as being at low risk of myocardial infarction, mortality or hospital admission (Early Chest pain Admission, Myocardial infarction, and Mortality (ECAMM) score) represented 31%-57% of the cohort, with total annual costs estimated at $60.6 million-$135.4 million, depending on the score cut-off used.

CONCLUSIONS

Total annual costs for acute chest pain presentations are increasing, and a significant proportion of the cost burden relates to low-risk patients and non-specific pain. These data highlight the need to improve the cost-efficiency of chest pain care pathways.

Opportunities and Challenges of Computed Tomography Coronary Angiography in the Investigation of Chest Pain in the Emergency Department-A Narrative Review

Chest pain is one of the most common presentations to emergency departments. However, only 5.1% will be diagnosed with an acute coronary syndrome, representing considerable time and expense in the diagnosis and investigation of the patients eventually found not to be suffering from an acute coronary syndrome. PubMed and Medline databases were searched with variations of the terms "chest pain", "emergency department", "computed tomography coronary angiography". After review, 52 articles were included. Computed tomography coronary angiography (CTCA) is a class I endorsement for investigating chest pain in major international societal guidelines. CTCA offers excellent sensitivity and negative predictive value in identifying patients with coronary disease, with prognostic data impacting patient management. If CTCA is to be applied to all comers, it is pertinent to discuss the advantages and potential pitfalls if use in the Australian system is to be increased.

Multicultural emergency medicine epidemiology: A health economic analysis of patient visits

OBJECTIVE

There is growing evidence to suggest that culturally and linguistically diverse (CALD) patients cost the health system more than non-CALD patients because of a higher burden of disease and increased resource consumption. The present study aimed to compare the ED resource utilisation of CALD and non-CALD patients at a tertiary hospital in Sydney, Australia.

METHODS

The total ED resource utilisation was calculated by separating each visit into diagnostic test cost and time spent in ED components. The time component was calculated using the product of the total length of stay and a resource cost per unit time measure. Diagnostic tests were costed using the Australian Medicare Benefit Schedule. A generalised additive model was developed to estimate the isolated effect of CALD status on the resource utilisation during an ED visit.

RESULTS

CALD patients had a higher median resource utilisation than non-CALD patients ($736.93 vs $701.36, P < 0.0001); however, the generalised additive model demonstrated that CALD status was not independently associated with increased resource utilisation.

CONCLUSION

CALD status is not an independent influence on ED resource utilisation but other explanatory variables such as increased age and altered case-mix appear to have a much greater influence. There may, however, be other reasons to consider CALD loading such as equity in healthcare and to address poorer overall health outcomes for CALD patients.

Single High-Sensitivity Point-of-Care Whole-Blood Cardiac Troponin I Measurement to Rule Out Acute Myocardial Infarction at Low Risk

BACKGROUND

High-sensitivity cardiac troponin (hs-cTn) laboratory assays are used to rule out myocardial infarction (MI) on presentation, but prolonged result turnaround times can delay patient management. Our primary aim was to identify patients at low risk of index MI using a rapid point-of-care (POC) whole-blood hs-cTnI assay at presentation with potential early patient discharge.

METHODS

Consecutive patients presenting to the emergency department from 2 prospective observational studies with suspected acute coronary syndrome were enrolled. A POC hs-cTnI assay (Atellica VTLi) threshold using whole blood at presentation, which resulted in a negative predictive value of ≥99.5% and sensitivity of >99% for index MI, was derived (SEIGE [Safe Emergency Department Discharge Rate]) and validated with plasma (SAMIE [Suspected Acute Myocardial Infarction in Emergency]). Event adjudications were established with hs-cTnI assay results from routine clinical care. The primary outcome was MI at 30 days.

RESULTS

A total of 1086 patients (8.1% with MI) were enrolled in a US derivation cohort (SEIGE) and 1486 (5.5% MI) in an Australian validation cohort (SAMIE). A derivation whole-blood POC hs-cTnI concentration of <4 ng/L provided a sensitivity of 98.9% (95% CI, 93.8%-100%) and negative predictive value of 99.5% (95% CI, 97.2%-100%) for ruling out MI. In the validation cohort, the sensitivity was 98.8% (95% CI, 93.3%-100%), and negative predictive value was 99.8% (95% CI, 99.1%-100%); 17.8% and 41.8%, respectively, were defined as low risk for discharge. The 30-day adverse cardiac events were 0.1% (n=1) for SEIGE and 0.8% (n=5) for SAMIE.

CONCLUSIONS

A POC whole-blood hs-cTnI assay permits accessible, rapid, and safe exclusion of MI and may expedite discharge from the emergency department.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT04772157. URL: https://www.australianclinicaltrials.gov.au/anzctr_feed/form; Unique identifier: 12621000053820.

Clinical characteristics of Aboriginal and Torres Strait Islander emergency department patients with suspected acute coronary syndrome

OBJECTIVES

To describe the demographics, presentation characteristics, clinical features and cardiac outcomes for Aboriginal and Torres Strait Islander patients who present to a regional cardiac referral centre ED with suspected acute coronary syndrome (ACS).

METHODS

This was a single-centre observational study conducted at a regional referral hospital in Far North Queensland, Australia from November 2017 to September 2018 and January 2019 to December 2019. Study participants were 278 Aboriginal and Torres Strait Islander people presenting to an ED and investigated for suspected ACS. The main outcome measure was the proportion of patients with ACS at index presentation and differences in characteristics between those with and without ACS.

RESULTS

ACS at presentation was diagnosed in 38.1% of patients (n = 106). The mean age of patients with ACS was 53.5 years (SD 9.5) compared with 48.7 years (SD 12.1) in those without ACS (P = 0.001). Patients with ACS were more likely to be male (63.2% vs 39.0%, P < 0.001), smokers (70.6% vs 52.3%, P = 0.002), have diabetes (56.6% vs 38.4%, P = 0.003) and have renal impairment (24.5% vs 10.5%, P = 0.002).

CONCLUSIONS

Aboriginal and Torres Strait Islander patients with suspected ACS have a high burden of traditional cardiac risk factors, regardless of whether they are eventually diagnosed with ACS. These patients may benefit from assessment for coronary artery disease regardless of age at presentation.

The influence of ambulance offload time on 30-day risks of death and re-presentation for patients with chest pain

OBJECTIVE

To assess whether ambulance offload time influences the risks of death or ambulance re-attendance within 30 days of initial emergency department (ED) presentations by adults with non-traumatic chest pain.

DESIGN, SETTING

Population-based observational cohort study of consecutive presentations by adults with non-traumatic chest pain transported by ambulance to Victorian EDs, 1 January 2015 - 30 June 2019.

PARTICIPANTS

Adults (18 years or older) with non-traumatic chest pain, excluding patients with ST elevation myocardial infarction (pre-hospital electrocardiography) and those who were transferred between hospitals or not transported to hospital (eg, cardiac arrest or death prior to transport).

MAIN OUTCOME MEASURES

Primary outcome: 30-day all-cause mortality (Victorian Death Index data).

SECONDARY OUTCOME

Transport by ambulance with chest pain to ED within 30 days of initial ED presentation.

RESULTS

We included 213 544 people with chest pain transported by ambulance to EDs (mean age, 62 [SD, 18] years; 109 027 women [51%]). The median offload time increased from 21 (IQR, 15-30) minutes in 2015 to 24 (IQR, 17-37) minutes during the first half of 2019. Three offload time tertiles were defined to include approximately equal patient numbers: tertile 1 (0-17 minutes), tertile 2 (18-28 minutes), and tertile 3 (more than 28 minutes). In multivariable models, 30-day risk of death was greater for patients in tertile 3 than those in tertile 1 (adjusted rates, 1.57% v 1.29%; adjusted risk difference, 0.28 [95% CI, 0.16-0.42] percentage points), as was that of a second ambulance attendance with chest pain (adjusted rates, 9.03% v 8.15%; adjusted risk difference, 0.87 [95% CI, 0.57-1.18] percentage points).

CONCLUSIONS

Longer ambulance offload times are associated with greater 30-day risks of death and ambulance re-attendance for people presenting to EDs with chest pain. Improving the speed of ambulance-to-ED transfers is urgently required.

Long-term cost-effectiveness of Dexcom G6 real-time continuous glucose monitoring system in people with type 1 diabetes in Australia

INTRODUCTION

Real-time continuous glucose monitoring (rt-CGM) allows patients with diabetes to adjust insulin dosing, potentially improving glucose control. This study aimed to compare the long-term cost-effectiveness of the Dexcom G6 rt-CGM device versus self-monitoring of blood glucose (SMBG) and flash glucose monitoring (FGM) in Australia in people with type 1 diabetes (T1D).

METHODS

Long-term costs and clinical outcomes were estimated using the CORE Diabetes Model. Clinical input data for the analysis of rt-CGM versus SMBG and FGM were sourced from the DIAMOND study and a network meta-analysis, respectively. Rt-CGM and FGM were associated with quality of life (QoL) benefits due to reduced fear of hypoglycaemia (FoH) and fingerstick testing. Analyses were performed over a lifetime time horizon from an Australian healthcare payer perspective, including direct costs from published data. Future costs and clinical outcomes were discounted at 5% per annum.

RESULTS

Rt-CGM was associated with an increased quality-adjusted life expectancy of 1.199 quality-adjusted life years (QALYs), increased mean total lifetime costs of AUD 21,596 and an incremental cost-effectiveness ratio (ICER) of AUD 18,020 per QALY gained compared with SMBG. Compared with FGM, rt-CGM was associated with an increased quality-adjusted life expectancy of 0.569 QALYs, increased mean total lifetime costs of AUD 11,064 and an ICER of AUD 19,455 per QALY gained. Key drivers of outcomes included HbA_1c benefits and QoL benefits associated with reduced FoH and fingerstick testing.

CONCLUSIONS

Due to improved clinical outcomes and QoL gains rt-CGM is highly cost-effective compared with SMBG and FGM in people with T1D in Australia.

Emergency Department Assessment of Suspected Acute Coronary Syndrome Using the IMPACT Pathway in Aboriginal and Torres Strait Islander People

OBJECTIVES

The Improved Assessment of Chest pain Trial (IMPACT) pathway is an accelerated strategy for the assessment of emergency patients presenting with suspected acute coronary syndrome (ACS). The objective of this study was to report outcomes for Aboriginal and Torres Strait Islander patients deemed low-, intermediate-, or high-risk according to this pathway.

DESIGN

This was a prospective observational trial conducted between November 2017 and December 2019.

SETTING

Regional hospital in Far North Queensland.

PARTICIPANTS

Aboriginal and Torres Strait Islander people presenting to the Emergency Department with suspected ACS were asked to participate. Participants were stratified as low-, intermediate- or high-risk of ACS according to the IMPACT pathway. High-and intermediate risk patients were managed according to the IMPACT pathway. Management of low-risk patients included additional inpatient cardiac testing, which was not part of the original IMPACT pathway.

MAIN OUTCOME MEASURES

The primary outcome was acute coronary syndrome within 30-days. Secondary outcomes included length of stay and prevalence of objective testing.

RESULTS

A total of 155 participants were classified as either at low-risk (n=18 11.6%), intermediate-risk (n=87 56.1%), or high-risk (n=50 32.3%) of ACS. Thirty-day (30-day) ACS occurred in 29 (18.6%) patients, which included 26 (52.0%) high-risk patients and three (3.4%) intermediate-risk patients. No patients in the low-risk group were diagnosed with ACS during their index presentation or by 30-days. Median hospital length-of-stay was 11.9 hours (interquartile range [IQR] 5.3-20.2 hrs) for low- and 15.5 hours (IQR 5.9-29.2 hrs) for intermediate-risk patients.

CONCLUSION

The IMPACT pathway, which has been associated with reduced LOS in other settings, could be safely implemented for patients of Aboriginal and Torres Strait Islander origin, classifying two-thirds as low- or intermediate risk. However, a clinically significant proportion of Aboriginal and Torres Strait Islander patients experience cardiac events, which supports the need to provide early objective testing for coronary artery disease.

Incidence, diagnoses and outcomes of ambulance attendances for chest pain: A population-based cohort study

AIMS

Non-traumatic chest pain is one of the most common reasons for calls for emergency assistance and places a significant burden on health services. This study aimed to determine age- and sex-specific incidences, diagnoses, and outcomes of patients with chest pain attended by paramedics using a large population-based sample.

METHODS

Consecutive emergency medical services (EMS) attendances for non-traumatic chest pain in Victoria, Australia from January 2015 to June 2019 were included. Data were individually linked to emergency, hospital admission and mortality records.

RESULTS

During the study period (representing 22,186,930 person-years), chest pain was the reason for contacting EMS in 257,017 of 2,736,570 attendances (9.4%). Overall incidence of chest pain attendances was 1,158 (per 100,000 person-years) with a higher incidence observed with increasing age, among females, among Aboriginal and Torres Strait Islanders, in regional settings, and in socially disadvantaged areas. The most common diagnoses were non-specific pain (46%; 30-day mortality 0.5%), non-ST elevation myocardial infarction (5.3%; mortality 1.3%), pneumonia (3.8%; mortality 3.9%), stable coronary syndromes (3.5%; mortality 0.8%), unstable angina (3.3%; mortality 1.3%), and ST-elevation myocardial infarction (2.8%; mortality 7.0%), while pulmonary embolism (0.7%; mortality 3.2%) and aortic pathologies (0.2%; mortality 22.2%) were rare.

CONCLUSIONS

Chest pain accounts for one in ten ambulance calls, and underlying causes are diverse, with substantial differences according to age and sex. Almost half of patients are discharged from hospital with a diagnosis of non-specific pain and low rates of mortality.

Implementation and evaluation of a rural general practice assessment pathway for possible cardiac chest pain using point-of-care troponin testing: a pilot study

OBJECTIVES

To assess the feasibility and acceptability, and additionally to preliminarily evaluate, the effectiveness and safety of an accelerated diagnostic chest pain pathway in rural general practice using point-of-care troponin to identify patients at low risk of acute myocardial infarction, avoiding unnecessary patient transfer to hospital and enabling early discharge home.

DESIGN

A prospective observational pilot evaluation.

SETTING

Twelve rural general (family) practices in the Midlands region of New Zealand.

PARTICIPANTS

Patients aged ≥18 years who presented acutely to rural general practice with suspected ischaemic chest pain for whom the doctor intended transfer to hospital for serial troponin measurement.

OUTCOME MEASURES

The proportion of patients managed using the low-risk pathway without transfer to hospital and without 30-day major adverse cardiac event (MACE); pathway adherence; rate of 30-day MACE; patient satisfaction with care; and agreement between point-of-care and laboratory measured troponin concentrations.

RESULTS

A total of 180 patients were assessed by the pathway. The pathway classified 111 patients (61.7%) as low-risk and all were managed in rural general practice with no 30-day MACE (0%, 95% CI 0.0% to 3.3%). Adherence to the low-risk pathway was 95.5% (106 out of 111). Of the 56 patients classified as non-low-risk and referred to hospital, 9 (16.1%) had a 30-day MACE. A further 13 non-low-risk patients were not transferred to hospital, with no events. The sensitivity of the pathway for 30-day MACE was 100.0% (95% CI 70.1% to 100%). Of low-risk patients, 94% reported good to excellent satisfaction with care. Good concordance was observed between point-of-care and duplicate laboratory measured troponin concentrations.

CONCLUSIONS

The use of an accelerated diagnostic chest pain pathway incorporating point-of-care troponin in a rural general practice setting was feasible and acceptable, with preliminary results suggesting that it may safely and effectively reduce the urgent transfer of low-risk patients to hospital.

Association of Socioeconomic Status With Outcomes and Care Quality in Patients Presenting With Undifferentiated Chest Pain in the Setting of Universal Health Care Coverage

BACKGROUND

This study aimed to assess whether there are disparities in incidence rates, care, and outcomes for patients with chest pain attended by emergency medical services according to socioeconomic status (SES) in a universal health coverage setting.

METHODS AND RESULTS

This was a population‐based cohort study of individually linked ambulance, emergency, hospital admission, and mortality data in the state of Victoria, Australia, from January 2015 to June 2019 that included 183 232 consecutive emergency medical services attendances for adults with nontraumatic chest pain (mean age 62 [SD 18] years; 51% women) and excluded out‐of‐hospital cardiac arrest and ST‐segment–elevation myocardial infarction. Age‐standardized incidence of chest pain was higher for patients residing in lower SES areas (lowest SES quintile 1595 versus highest SES quintile 760 per 100 000 person‐years; P<0.001). Patients of lower SES were less likely to attend metropolitan, private, or revascularization‐capable hospitals and had greater comorbidities. In multivariable models adjusted for clinical characteristics and final diagnosis, lower SES quintiles were associated with increased risks of 30‐day and long‐term mortality, readmission for chest pain and acute coronary syndrome, lower acuity emergency department triage categorization, emergency department length of stay >4 hours, and emergency department or emergency medical services discharge without hospital admission and were inversely associated with use of prehospital ECGs and transfer to a revascularization‐capable hospital for patients presenting to non‐percutaneous coronary intervention centers.

CONCLUSIONS

In this study, lower SES was associated with a higher incidence of chest pain presentations to emergency medical services and differences in care and outcomes. These findings suggest that substantial disparities for socioeconomically disadvantaged chest pain cohorts exist, even in the setting of universal health care access.

Impact of Pre-Hospital Activation of STEMI on False Positive Activation Rate and Door to Balloon Time

BACKGROUND

Pre-hospital identification of ST-segment elevation myocardial infarction (STEMI) by paramedical staff reduces reperfusion time. However, the impact of this approach on the rate of unnecessary activation of coronary catheterisation lab (CCL) remains unclear.

METHODS

The study reviewed consecutive STEMI patients over 3 years (July 2015 to June 2018) from all primary percutaneous coronary intervention (PPCI) centres and inter-hospital transfers (IHT) from non-PPCI capable centres in Western Australia. Out-of-hospital cardiac arrests (OOHCA) and STEMI calls for in-patients receiving treatment for other medical reasons were excluded.

RESULTS

During the 3 years study period, 1,736 STEMI cases were recorded. Pre-hospital (PH) activation occurred in 799 (46%) cases. Median door to balloon time (D2BT) was 68 minutes (IQR 63 mins). D2BT for PH activation (40 min [IQR 25 min]) was significantly lower than both the PPCI centre emergency department (ED) activation (86 min [IQR 55 min]) and IHT activation groups (108 min [IQR 55 min]), p-value <0.00001. In PH activation group 98% patients received primary PCI in less than 90 minutes compared to 54% and 26% patients in the ED and the IHT activation groups, respectively. False positive STEMI activation rate was lower in the PH activation group (2.75%) compared to ED activation (5.4%) and IHT group (6%), p-value 0.0115. The false positive rate did not vary significantly between working hours and out-of-hour calls (5% vs 4%, p-value=0.304). Pericarditis, coronary artery disease other than STEMI, atypical chest pain, and stress induced cardiomyopathy were the common diagnoses in false positive activations.

CONCLUSION

Pre-hospital activation of STEMI leads to reduced door to balloon times without a significant increase in inappropriate procedures, though false positive activation rates are unclear. The majority of STEMI patients transferred from non-PPCI centres failed to receive reperfusion therapy within 90 minutes of initial hospital presentation. Further studies are required to assess the benefits of thrombolysis in selected patients in inter-hospital transfer group.

A Comparison of Clinical Characteristics and Outcomes Between Indigenous and Non-Indigenous Patients Presenting to Townsville Hospital Emergency Department With Chest Pain

BACKGROUND

Indigenous Australians have a high rate of ischaemic heart disease (IHD). There is a paucity of local data for North Queensland regarding the clinical characteristics of Indigenous people who present to the emergency department (ED) with chest pain. The aim of the study is to compare the cardiovascular risk factors, social characteristics, and the clinical outcomes between Indigenous and non-Indigenous patients who presented with cardiac-related chest pain.

METHODS

This is a retrospective single-centre audit. The data was collected through chart reviews of chest pain presentations to the Townsville University Hospital Emergency Department from January to December 2017. We categorised the patients into Indigenous and non-Indigenous groups and compared their cardiac risk factors and social characteristics. We further classified the patients into three diagnosis groups and we measured the clinical outcomes in the patients with a diagnosis of cardiac-related chest pain. We used a data linkage to the Registry of Births, Deaths and Marriages for the death outcomes. A multivariable analysis was done to determine the risk of major adverse cardiac event (MACE) for Indigenous vs non-Indigenous patients.

RESULTS

Indigenous patients were over-represented making up 19.1% of the total cohort (compared with 11.1% of the North Queensland Indigenous population) and presented at a younger age (median age: 45 vs 52, p<0.005). Traditional cardiovascular risk factors were significantly higher in Indigenous patients. The incidence of discharge against medical advice was also higher (6.5% vs 2.7%, p<0.005). There was an underutilisation of the local chest pain pathway amongst the Indigenous group (35.8% vs 44.7%, p<0.005). In patients with a diagnosis of cardiac-related chest pain, the rate of receiving invasive coronary angiogram procedures was similar in both cohorts (44.5% vs 43.7%, p=0.836). With regards to outcomes, Indigenous patients suffered from acute coronary syndrome (ACS) at a younger median age (51 vs 64, p<0.005) and were more likely to have severe three vessel disease (17% vs 6%, p<0.005) leading to coronary bypass graft surgery (CABG) (19% vs 6%, p<0.005). When adjusted for age, gender, and comorbidities, Indigenous patients were more likely to have MACE within 1 year of their chest pain presentation, compared with non-Indigenous patients with the same diagnosis (adjusted odds ration [AOR]=2.0, 95% CI [1.1, 3.8], p=0.03).

CONCLUSION

In our study, Indigenous patients carried a heavier burden of cardiovascular risk factors, presented at a younger age, with more severe coronary disease and had a higher rate of CABG. We found an underutilisation of the local chest pain protocol amongst the Indigenous cohort, which suggests a need to improve support structures in the ED. In our multivariable analysis, Indigenous patients suffered from a significantly higher MACE compared to non-Indigenous patients which indicates that more collaborative efforts are needed to improve the cardiovascular health of local Aboriginal and Torres Strait Islander people.

Rapid Access Chest Pain Clinics: An Australian Cost-Benefit Study

OBJECTIVE

Chest pain is a large health care burden in Australia and around the world. Its management requires specialist assessment and diagnostic tests, which can be costly and often lead to unnecessary hospital admissions. There is a growing unmet clinical need to improve the efficiency and management of chest pain. This study aims to show the cost-benefit of rapid access chest pain clinics (RACC) as an alternative to hospital admission.

DESIGN

Retrospective cost-benefit analysis for 12 months.

SETTING

RACCs in three Sydney tertiary referral hospitals.

MAIN OUTCOME MEASURES

Cost per patient.

RESULTS

Hospitals A, B and C implemented RACCs but each operating with slightly different staffing, referral patterns, and diagnostic services. All RACCs had similar costs per patient of AUD$455.25, AUD$427.12 and AUD$474.45, hospitals A, B and C respectively, and similar cost benefits per patient of AUD$1168.75, AUD$1196.88 and AUD$1,149.55, respectively. At least 28%, 26% and 29% of these RACC patients for hospitals A, B, and C, respectively, would have otherwise had to have been admitted to hospital for the model to be cost-beneficial.

CONCLUSION

This study shows that a RACC model of care is cost-beneficial in the state of NSW as an alternative strategy to inpatient care for managing chest pain. Scaling up to a national level could represent an even larger benefit for the Australian health system.

Can existing electronic medical records be used to quantify cardiovascular risk at point of care?

BACKGROUND

Using electronic data for cardiovascular risk stratification could help in prioritising healthcare access and optimise cardiovascular prevention.

AIMS

To determine whether assessment of absolute cardiovascular risk (Australian Absolute Cardiovascular Disease Risk, ACVDR) and short-term ischaemic risk (HEART Score) are possible from available data in Electronic Medical Record (EMR) and My Health Record (MHR) of patients presenting with acute cardiac symptoms to a Rapid Access Cardiology Clinic (RACC).

METHODS

Audit of EMR and MHR on 200 randomly selected adults who presented to RACC between 1st of March 2017 and 4th February 2020. The main outcomes were the proportion of patients for which an ACVDR and HEART Score could be calculated.

RESULTS

Mean age was 55.2 ± 17.8 years and 43% were female. Most were referred from Emergency (85%) for chest pain (52%). 46% had hypertension, 35% obesity, 20% diabetes mellitus, 17% ischaemic heart disease, and 18% were current smokers. There was no significant difference in MHR accessibility with age, gender, and number of comorbidities. ACVDR could be estimated for 17.5% (EMR) and 0% (MHR) of patients. None had complete data to estimate HEART Score in either EMR or MHR. Most commonly missing variables for ACVDR were blood pressure (MHR) and HDL-C (EMR), and for HEART Score were body mass index and comorbidities (MHR and EMR).

CONCLUSIONS

Significant gaps are apparent in electronic medical data capture of key variables to perform cardiovascular risk assessment. Medical data capture should prioritise the collection of clinically important data to help address gaps in cardiovascular management. This article is protected by copyright. All rights reserved.

Diagnostic accuracy of the HEART Pathway and EDACS-ADP when combined with a 0-hour/1-hour hs-cTnT protocol for assessment of acute chest pain patients

BACKGROUND/AIM

In ED chest pain patients, a 0-hour/1-hour protocol based on high sensitivity cardiac troponin T (hs-cTnT) tests combined with clinical risk stratification in diagnosing acute coronary syndrome is recommended. Two of the most promising risk stratification tools are the History, ECG, Age, Risk Factors and Troponin (HEART) and Emergency Department Assessment of Chest Pain (EDAC) scores. Few studies have assessed the diagnostic accuracy of the 0-hour/1-hour hs-cTnT protocol when combined with HEART score, and none with EDACS. In ED chest pain patients, we aimed to evaluate the diagnostic accuracy of a 0-hour/1-hour hs-cTnT protocol combined the HEART Pathway, or the EDACS accelerated diagnostic pathway (EDACS-ADP).

METHODS

This was a secondary analysis of data from a prospective observational study enrolling 1167 ED chest pain patients who visited the ED at Skåne University Hospital in Lund, Sweden in the period between February 2013 and April 2014. HEART and EDAC scores were assessed together with hs-cTnT at 0 and 1 hour and compared with HEART score alone. Sensitivity, specificity, negative predictive value (NPV) and likelihood ratios were evaluated. The primary outcome was major adverse cardiac events (MACE) including unstable angina within 30 days. The secondary outcome was index visit acute myocardial infarction (AMI).

RESULTS

A total of 939 patients were included in the final analysis. When combined with 0-hour/1-hour hs-cTnT testing, the HEART Pathway and EDACS-ADP identified 49.8% and 49.6% of the patients for rule-out, with NPVs for 30-day MACE of 99.8% and 99.1%, compared with the HEART score alone that identified 53.4% of the patients for rule-out with NPV of 99.2%. The NPV for index visit AMI were 100%, 99.8% and 99.2%, respectively.

CONCLUSION

The combination of the HEART Pathway or the EDACS-ADP with a 0-hour/1-hour hs-cTnT protocol allows safe and early rule-out in a large proportion of ED chest pain patients.

The NSW Pathology Atlas of Variation: Part II-The Association of Variation in Emergency Department Laboratory Investigations With Outcomes for Patients Presenting With Chest Pain

STUDY OBJECTIVE

Laboratory test use varies across emergency departments (EDs), yet little is known about the effect of this variation on outcomes. The aim of this study is 2-fold: to stratify EDs into clusters based on similar test use, and to determine whether the clusters differ in patient operational outcomes among patients presenting to EDs with undifferentiated chest pain.

METHODS

We conducted a retrospective cohort study of 222,788 patients presenting with undifferentiated chest pain at 44 EDs across New South Wales, Australia, from January 2017 to September 2018. The operational outcomes measured in this study included ED length of stay, hospital admission, the Emergency Treatment Performance target, and 7- and 15-day all-cause and same-cause ED revisit rates. We performed a hierarchic cluster analysis to identify ED clusters and mixed-effects models to determine the association between the clusters and the operational outcomes.

RESULTS

Two ED clusters, moderate users (18 EDs) and high users (26 EDs), were identified. After adjustment for confounders, the median ED length of stay was greater by 15.7% (equivalent to 33.4 minutes) in high versus moderate users (95% confidence interval 6.62 to 25.52 minutes), and high users were less likely to achieve the Emergency Treatment Performance target versus moderate users (odds ratio 0.66; 95% confidence interval 0.50 to 0.86). There were no significant differences between the users in hospital admission and ED revisit rates.

CONCLUSION

Our findings suggest that reducing test use may reduce ED length of stay and improve the chance of achieving the Emergency Treatment Performance target.

Long-Term Outcomes Following Rapid Access Chest Pain Clinic Assessment: First Australian Data

Australian guidelines recommend prompt evaluation of patients presenting to emergency departments with chest pain, found to be low risk for acute coronary syndromes, and cardiologist-led Rapid Access Chest Pain Clinics (RACPC) have been proposed as a model to provide such care. Initial Australian experience of RACPCs suggests excellent short-term outcomes, and that they are cost-beneficial, though little data exists examining longer-term outcomes. The present study therefore examines such longer-term outcomes to beyond 5 years following presentation to an RACPC in an Australian tertiary metropolitan centre.

Absolute risk assessment for guiding cardiovascular risk management in a chest pain clinic

OBJECTIVES

To assess the efficacy of a pro-active, absolute cardiovascular risk-guided approach to opportunistically modifying cardiovascular risk factors in patients without coronary ischaemia attending a chest pain clinic.

DESIGN

Prospective, randomised, open label, blinded endpoint study.

SETTING

The rapid access chest pain clinic of Royal Hobart Hospital, a tertiary hospital.

PARTICIPANTS

Patients who presented to the chest pain clinic between 1 July 2014 and 31 December 2017 who had intermediate to high absolute cardiovascular risk scores (5-year risk ≥ 8%). Patients with known cardiac disease or from groups with clinically determined high risk of cardiovascular disease were excluded.

MAIN OUTCOME MEASURES

The primary endpoint was change in 5-year absolute risk score (Australian absolute risk calculator) at follow-up (at least 12 months after baseline assessment). Secondary endpoints were changes in lipid profile, blood pressure, smoking status, and body mass index, and major adverse cardiovascular events.

RESULTS

The mean change in risk at follow-up was +0.4 percentage points (95% CI, -0.8 to 1.5 percentage points) for the 98 control group patients and -2.4 percentage points (95% CI, -1.5 to -3.4 percentage points) for the 91 intervention group patients; the between-group difference in change was 2.7 percentage points (95% CI, 1.2-4.1 percentage points). Mean changes in lipid profile, systolic blood pressure, and smoking status were larger for the intervention group, but not statistically different from those for the control group.

CONCLUSIONS

An absolute cardiovascular risk-guided, pro-active risk factor management strategy employed opportunistically in a chest pain clinic significantly improved 5-year absolute cardiovascular risk scores.

TRIAL REGISTRATION

Australia New Zealand Clinical Trial Registry, ACTRN12617000615381 (retrospective).

Invasive Coronary Angiography after Chest Pain Presentations to Emergency Departments

We investigated patients presenting to emergency departments (EDs) with chest pain to identify factors that influence the use of invasive coronary angiography (ICA). Using linked ED, hospitalisations, death and cardiac biomarker data, we identified people aged 20 years and over who presented with chest pain to tertiary public hospital EDs in Western Australia from 1 January 2016 to 31 March 2017 (ED chest pain cohort). We report patient characteristics, ED discharge diagnosis, pathways to ICA, ICA within 90 days, troponin test results, and gender differences. Associations were examined with the Pearson Chi-squared test and multivariate logistic regression. There were 16,974 people in the ED chest pain cohort, with a mean age of 55.6 years and 50.7% males, accounting for 20,131 ED presentations. Acute coronary syndrome was the ED discharge diagnosis in 10.4% of presentations. ED pathways were: discharged home (57.5%); hospitalisation (41.7%); interhospital transfer (0.4%); and died in ED (0.03%)/inpatients (0.3%). There were 1546 (9.1%) ICAs performed within 90 days of the first ED chest pain visit, of which 59 visits (3.8%) had no troponin tests and 565 visits (36.6%) had normal troponin. ICAs were performed in more men than women (12.3% vs. 6.1%, p < 0.0001; adjusted OR 1.89, 95% CI 1.65, 2.18), and mostly within 7 days. Equal numbers of males and females present with chest pain to tertiary hospital EDs, but men are twice as likely to get ICA. Over one-third of ICAs occur in those with normal troponin levels, indicating that further investigation is required to determine risk profile, outcomes and cost effectiveness.

Where Is the Value of Laboratory Medicine and How Do You Unlock It?

BACKGROUND

The innovation pathway by which a newly discovered biomarker is developed into a medical test and used in routine clinical practice comprises a number of different processes split between 2 phases. The first follows on from biomarker discovery and involves the development of a robust analytical method, the accumulation of evidence to show its clinical and cost-effectiveness, and then adoption into clinical pathways. The second phase is one of implementation and sustainability, with active performance management to ensure that the test continues to deliver the benefits promised at the time of its adoption.

CONTENT

To date there has been much more emphasis on the first phase of discovery and accumulation of evidence to demonstrate effectiveness. Insufficient attention has been paid to the second phase of translating that evidence into routine practice, with little real-world evidence to demonstrate the benefits to all of the stakeholders involved in delivering and receiving care. Changes in healthcare that include a move away from activity-based costing to a more value-based approach require more attention be paid to what happens after a test is adopted, including an understanding of the clinical pathway, the stakeholders within that pathway, and the benefits and "disbenefits" that accrue to these stakeholders.

SUMMARY

The value proposition provides a guide for successful implementation of a test. Although it can address both adoption and implementation, it highlights that the requirements for test implementation are quite different to those of adoption, with an emphasis on real-world evidence and outcomes.

Widespread Introduction of a High-Sensitivity Troponin Assay: Assessing the Impact on Patients and Health Services

Adoption of High-sensitivity troponin (hs-cTn) assays by hospitals worldwide is increasing. We sought to determine the effects of a simultaneous state-wide hs-cTn assay introduction on the implementing health service. A quasi-experimental pre–post design was used. Participants included all adult patients presenting to 21 Australian hospitals who had troponin testing commenced within the Emergency Department (ED). Data were collected for 124,357 episodes of care between 30 April 2018 and 23 April 2019; six months pre- and six months post-implementation of the assay. The primary outcome was hospital length of stay (LOS). Secondary outcomes included ED LOS, 90-day cardiovascular mortality, elevated troponin, diagnosis of acute myocardial infarction (AMI), admission to a cardiology ward, invasive cardiac procedures, and total hospital costs. Following hs-cTn implementation, there was a 1.9-h (95% CI: −2.9 to −1.0 h) reduction in overall LOS. This equated to a cost saving of over 9 million Australian dollars per year. There was no increase in diagnosis of AMI, invasive cardiac procedures or ward admissions. The use of hs-cTn assays facilitates important benefits for health services by enabling more rapid evaluation protocols within the ED. This benefit may be considerable given the large cohort of emergency patients with possible ACS.

Examining the translational success of an initiative to accelerate the assessment of chest pain for patients in an Australian emergency department: a pre-post study

Background

The Improved assessment of chest pain trial (IMPACT) protocol is an accelerated strategy for the risk stratification and management of patients presenting to the emergency department (ED) with chest pain. This study sought to describe the adoption, sustainability and health services implications of implementing the IMPACT protocol.

Methods

This was a study of adult patients in a large Australian tertiary hospital who had serial troponin testing commenced within the ED. Data from two periods were utilized; the pre-implementation period (8th April 2012 to 5th April 2014) and the post-implementation period (6th April 2014 to 2nd April 2016). The primary outcome was the proportion of patients undergoing accelerated care. Secondary endpoints were ED assessment time, hospital length of stay, and costs. Data were compared in the pre- and post-implementation periods.

Results

The proportion of patients receiving accelerated care increased from 3% in the pre- to 34% in the post-intervention period. This increase occurred rapidly after implementation of IMPACT and was sustained over a 2-year period. For patients with troponin concentrations <99th percentile, the mean ED assessment time reduced from 12.3 h in the pre- to 10.1 h in the post-implementation period. Mean hospital length of stay was similar in the pre- and post-implementation periods (82.4 and 80.9 h). The average cost of chest pain assessment reduced from $3520 pre implementation to $3204 post implementation; a $316 reduction per patient.

Conclusions

The IMPACT protocol was rapidly adopted and utilised after implementation into standard care. The initial increase in the proportion of patients undergoing accelerated assessment, followed by a plateau towards the end of the study period indicate adoption and sustainability of the IMPACT protocol over a two-year period. Modest reductions in length of stay and cost were seen after implementation. Given the large number of patients investigated for chest pain, such reductions may have substantial impact on the overall healthcare system.

Emergency Department Chest Pain Patients With or Without Ongoing Pain: Characteristics, Outcome, and Diagnostic Value of the Electrocardiogram

BACKGROUND

In emergency department (ED) chest pain patients, it is believed that the diagnostic accuracy of the electrocardiogram (ECG) for acute coronary syndrome (ACS) is higher during ongoing than abated chest pain.

OBJECTIVES

We compared patient characteristics and the diagnostic performance of the ECG in ED patients presenting with ongoing, vs. abated, chest pain.

METHODS

In total, 1132 unselected ED chest pain patients were analyzed. The patient characteristics and diagnostic accuracy for index visit ACS of the emergency physicians' interpretation of the ECG was compared in patients with and without ongoing chest pain. Logistic regression analysis was performed to control for possible confounders.

RESULTS

Patients with abated chest pain (n = 508) were older, had more comorbidities, and had double the risk of index visit ACS (15%) and major adverse cardiac events (MACE) at 30 days (15.6%) compared with patients with ongoing pain (n = 631; ACS 7.3%, 30-day MACE 7.4%). Sensitivity of the ECG for ACS was 24% in patients with ongoing pain and 35% in those without, specificity was 97% in both groups, negative predictive value was 94% and 89%, respectively, and positive likelihood ratio 10.6 and 7.8, respectively. When the diagnostic performance was controlled for confounders, there was no significant difference between the groups.

CONCLUSION

Our results indicate that ED chest pain patients with ongoing pain at arrival are younger, healthier, and have less ACS and 30-day MACE than patients with abated pain, but that there is no difference in the diagnostic accuracy of the ECG for ACS between the two groups.

Exploring Patient Experience of Chest Pain Before and After Implementation of an Early Rule-Out Pathway for Myocardial Infarction: A Qualitative Study

STUDY OBJECTIVE

High-sensitivity cardiac troponin assays enable myocardial infarction to be excluded in the emergency department (ED). As part of a prospective clinical trial, we explore how introducing an early rule-out pathway may affect patient experience of chest pain.

METHODS

In a qualitative study, participants presenting to the ED with suspected acute coronary syndrome, and for whom the diagnosis of myocardial infarction was excluded, were interviewed before (n=23) or after (n=26) implementation of an early rule-out pathway. Preimplementation, diagnosis of myocardial infarction was excluded on serial troponin testing requiring admission to the hospital. Postimplementation, diagnosis could be excluded in the ED, enabling direct patient discharge. Semistructured interviews exploring the patients' illness experience were conducted approximately 1 week postdischarge, transcribed verbatim, and analyzed thematically. Themes emerging pre- and postimplementation are described.

RESULTS

Common themes emerged across both pathways: participants commonly sought health care advice before presenting to the ED; a discordance may exist between the objective interpretation of troponin results by clinicians and the patients' experience of illness; and pretest information, trust in the clinician, and active listening may enhance reassurance gained from negative test results. Other themes related to the care pathway were that routine care procedures appeared to be a source of frustration for participants requiring hospital admission, and patients assessed with the early rule-out pathway appeared less likely to appraise their future health status.

CONCLUSION

The early rule-out of myocardial infarction may be enhanced by recognition of patient out-of-hospital experience and improved communication surrounding reassurance and future cardiovascular health goals.

Facilitators and barriers for emergency department clinicians using a rapid chest pain assessment protocol: qualitative interview research

Background

Guideline-based processes for the assessment of chest pain are lengthy and resource intensive. The IMProved Assessment of Chest Pain Trial (IMPACT) protocol was introduced in one Australian hospital Emergency Department (ED) to more efficiently risk stratify patients. The theoretical domains framework is a useful approach to assist in identifying barriers and facilitators to the implementation of new guidelines in clinical practice. The aim of this study was to understand clinicians’ perceptions of facilitators and barriers to the use of the IMPACT protocol.

Methods

Guided by the theoretical domains framework, semi-structured interviews with nine ED clinical staff (medical and nursing) were undertaken in 2016. Content analysis was conducted independently by two researchers to identify those theoretical domains that facilitated or hindered protocol use.

Results

Domains most often reported as fundamental to the use of the IMPACT protocol included ‘social/professional role and identity’, ‘environmental context and resources’ and ‘social influences’. These factors seemingly influenced professional confidence, with participants noting ‘goals’ that included standardisation of practice, enhanced patient safety, and reduced need for unnecessary testing. The domain ‘environmental context and resources’ also contained the most noted barrier - the need to inform new members of staff regarding protocol use. Opportunities to overcome this barrier included modelling of protocol use by staff at all levels and education – both formal and informal.

Conclusions

A range of domains were identified by ED staff as influencing their chest pain management behaviour. Fundamental to its use were champions/leaders that were trusted and accessible, as well as social influences (other staff within ED and other specialty areas) that enabled and supported protocol use. Research investigating the implementation and perceived use of the protocol at other sites, of varied geographical locations, is warranted.

Factors influencing physician risk estimates for acute cardiac events in emergency patients with suspected acute coronary syndrome

BACKGROUND

Emergency physicians frequently assess risk of acute cardiac events (ACEs) in patients with undifferentiated chest pain. Such estimates have been shown to have moderate to high sensitivity for ACE but are conservative. Little is known about the factors implicitly used by physicians to determine the pretest probability of risk. This study sought to identify the accuracy of physician risk estimates for ACE in patients presenting to the ED with chest pain and to identify the demographic and clinical information emergency physicians use in their determination of patient risk.

METHODS

This study used data from two prospective studies of consenting adult patients presenting to the ED with symptoms of possible acute coronary syndrome. ED physicians estimated the pretest probability of ACE. Multiple linear regression analysis was used to identify predictors of physician risk estimates. Logistic regression was used to determine whether there was a correlation between physicians' estimated risk and ACE.

RESULTS

Increasing age, male sex, abnormal ECG features, heavy/crushing chest pain and risk factors were correlated with physician risk estimates. Physician risk estimates were consistently found to be higher than the expected proportion of ACE from the sampled population.

CONCLUSION

Physicians systematically overestimate ACE risk. A range of factors are associated with physician risk estimates. These include factors strongly predictive of ACE, such as age and ECG characteristics. They also include other factors that have been shown to be unreliable predictors of ACE in an ED setting, such as typicality of pain and risk factors.

Medico-economic study of pain in an emergency department: a targeted literature review

Background: Pain management in emergency departments is a complex objective. The absence of a care pathway or a high level of activity complicates diagnostic or analgesic therapeutic strategies. Medical innovation can impact both individual practices and the functioning of an emergency department. Objective: We then wanted to understand how medico-economic studies on pain were carried out in an emergency department. Study design: We reviewed the literature of the last 20 years (between 1998 and 2018). Setting: Of 846 titles screened, a total of 268 abstracts qualified for further screening, and 578 titles were excluded. A total of 14 studies qualified for inclusion in the review. Studies on medico-economics in an emergency department are very diverse. None of the methods used are identical; the studies differ in their very nature (prospective, retrospective, cost-effectiveness, etc.) and the determination of emergency room costs differs according to the part of the world studied. In addition, organizational impact is rarely measured, although it is an essential dimension for choosing or not a medical innovation.

Cost-minimisation analysis alongside a pilot study of early Tissue Doppler Evaluation of Diastolic Dysfunction in Emergency Department Non-ST Elevation Acute Coronary Syndromes (TEDDy-NSTEACS)

OBJECTIVE

To estimate the cost implications of early angiography for patients with suspected non-ST elevation acute coronary syndrome (NSTEACS) using tissue Doppler imaging (TDI).

DESIGN

A decision tree model was used to synthesise data from the pilot study and literature sources. Sensitivity analyses tested the impact of assumptions incorporated into the analysis.

SETTING

Emergency department (ED), Brisbane, Australia.

PARTICIPANTS

Patients with suspected NSTEACS.

INTERVENTIONS

TDI as a diagnostic tool for triaging patients within 4 hours of presentation in addition to conventional risk stratification, compared with conventional risk stratification alone.

DATA SOURCES

Resource used for diagnosis and management were recorded prospectively and costed for 51 adults who had echocardiography within 24 hours of admission. Costs for conventional care were based on observed data. Cost estimates for the TDI intervention assumed patients classified as high risk at TDI (E/e'>14) progressed early to angiography with an associated 1-day reduction in length of stay.

PRIMARY OUTCOME MEASURES

Costs until discharge from the Australian healthcare perspective in 2016-2017 prices.

RESULTS

Findings suggest that using TDI as a diagnostic tool for triaging patients with suspected NSTEACS is likely to be cost saving by $A1090 (95% credible interval: $A573 to $A1703) per patient compared with conventional care. The results are mainly driven by the assumed reduction in length of stay due to the inclusion of early TDI in clinical decision-making.

CONCLUSIONS

This pilot study indicates that compared with conventional risk stratification, triaging patients presenting with suspected NSTEACS with TDI within 4 hours of ED presentation has potential cost savings. Findings assume a reduction in hospital stay is achieved for patients considered to be high risk at TDI. Larger, comparative studies with longer follow-up are needed to confirm the clinical effectiveness of TDI as a diagnostic strategy for NSTEACS, the assumed reduction in hospital stay and any cost saving.

Comparison of nine coronary risk scores in evaluating patients presenting to hospital with undifferentiated chest pain

INTRODUCTION

We compared performance of nine risk scores for coronary heart disease (CHD) among patients presenting to an emergency department (ED) with undifferentiated chest pain of possible coronary origin.

METHODS

A retrospective study was undertaken of adult patients presenting with chest pain to atertiary hospital ED with no electrocardiographs or troponin results diagnostic of ischemic chest pain (ICP) or acute coronary syndrome at ED presentation, and no clearly evident noncoronary diagnosis. Risk scores were applied using cut-points distinguishing low- from high-risk patients according to discharge diagnosis of noncardiac chest pain (NCCP) or ICP, respectively. A lower odds ratio (OR) for ICP denoted lower risk for ICP. Score performance was compared using area under receiver-operator characteristic curves (AUC) and predictive values.

RESULTS

A total of 401 patients were studied, of whom 123 (30.7%) had ICP as final diagnosis. Among the nine risk scores, those with greatest ability to detect low-risk patients were The North American Chest Pain Rule (NACPR) score (OR=0.35, 95% CI=0.27-0.46); History, ECG, Age, Risk Factors, and Troponin (HEART) score (OR=0.43; 95% CI=0.35-0.52); and Thrombolysis in Myocardial Infarction (TIMI) score (OR=0.49; 95% CI=0.41-0.58). Discrimination between patients with NCCP and those with ICP was greatest for HEART score (AUC=0.82; 95% CI=0.78-0.86) and lowest for Accelerated Diagnostic Protocol to Assess Patients with Chest Pain Symptoms Using Contemporary Troponins (ADAPT) score (AUC=0.63; 95% CI=0.58-0.69). In excluding ICP, ADAPT had negative predictive value (NPV) 100% (miss rate 0%) but classified only 1.7% of patients as low risk, compared to NACPR with NPV 98% (miss rate 2%), classifying 10.2% as low risk, and HEART with NPV 94% (miss rate 6%), classifying 32.4% as low risk.

CONCLUSION

The NACPR risk score maximized yield of low-risk patients with lowest miss rate for ICP, while HEART score classified highest proportion of low-risk patients but with a higher miss rate.

An evaluation of variation in pathology investigations and associated factors for adult patients presenting to emergency departments with chest pain: An observational study

OBJECTIVE

To determine variation in pathology test ordering practices and identify associated factors for adult patients presenting to emergency departments (ED) with chest pain and subsequently admitted with ischaemic heart disease.

METHODS

A retrospective study across six hospital EDs in New South Wales, Australia. A total of 6769 patient presentations between January 2014 and December 2017 met the inclusion criteria. Ordered pathology tests were grouped into three categories based on Australasian College for Emergency Medicine and the Royal College of Pathologists of Australasia recommendations: category I (no restriction in ordering), category II (can be ordered after consulting a supervisor) and category III (not for routine ordering in ED). The primary outcome was the proportion of category III test ordering across study EDs. Factors associated with category III test ordering were identified using a logistic regression.

RESULTS

A total of 34 936 pathology tests were ordered: 65.6% (n = 22 932) were category I/II tests and 34.4% (n = 12 004) were category III tests. Five tests (Calcium Magnesium Phosphate, Coagulation Studies, Lipase, C-reactive Protein and Blood Gas tests) accounted for 84.7% of all category III tests. The proportion of category III tests ordered varied by hospitals from 29.8% to 45.9%. The proportion of patients with at least one category III test was 76.3% (range across hospitals: 68.3%-95.6%). Increasing age, presentation to an ED at night, and those in an imminently life-threatening triage category were significantly associated with increased likelihood of category III test ordering. The proportion of category III tests decreased over time. EDs in medium and/or regional hospitals were more likely to order a category III test.

CONCLUSION

Pathology investigations for patients presenting with chest pain varied significantly across EDs suggesting opportunities to improve standardisation of test ordering practices.

Received care compared to ADP-guided care of patients admitted to hospital with chest pain of possible cardiac origin

Purpose

To assess the extent to which accelerated diagnostic protocols (ADPs), compared to traditional care, identify patients presenting to emergency departments (EDs) with chest pain who are at low cardiac risk and eligible for early ED discharge.

Patients and methods

Retrospective study of 290 patients admitted to hospital for further evaluation of chest pain following negative ED workup (no acute ischemic electrocardiogram [ECG] changes or elevation of initial serum troponin assay). Demographic data, serial ECG and troponin results, Thrombolysis in Myocardial Infarction (TIMI) score, cardiac investigations, and outcomes (confirmed acute coronary syndrome [ACS] at discharge and major adverse cardiac events [MACEs]) over 6 months of follow-up were analyzed. A validated ADP (ADAPT-ADP) was retrospectively applied to the cohort, and processes and outcomes of ADP-guided care were compared with those of care actually received.

Results

Patients had mean (±SD) TIMI score of 1.8 (±1.7); six (2.0%) patients were diagnosed with ACS at discharge. At 6 months, one patient (0.3%) re-presented with ACS and two (0.6%) died of non-coronary causes. The ADAPT-ADP defined 97 (33.4%) patients as being at low risk and eligible for early ED discharge, but who instead incurred mean hospital stay of 1.5 days, with 40.2% in telemetry beds, and 21.6% subject to non-invasive testing with only one positive result for coronary artery disease. None had a discharge diagnosis of ACS or developed MACE at 6 months.

Conclusion

Compared to traditional care, application of the ADAPT-ADP would have allowed one-third of chest pain patients with initially negative investigations in ED to have been safely discharged from ED.

Rapid-access cardiology services: can these reduce the burden of acute chest pain on Australian and New Zealand health services?

Chest pain is common and places a significant burden on hospital resources. Many patients with undifferentiated low- to intermediate-risk chest pain are admitted to hospital. Rapid-access cardiology (RAC) services are hospital co-located, cardiologist-led outpatient clinics that provide rapid assessment and immediate management but not long-term management. This service model is described as part of chest pain management and the National Service Framework for coronary heart disease in the United Kingdom (UK). We review the evidence on the effectiveness, safety and acceptability of RAC services. Our review finds that early assessment in RAC outpatient services of patients with suspected angina, without high-risk features suspicious of an acute coronary syndrome, is safe, can reduce hospitalisations, is cost effective and has good medical practitioner and patient acceptability. However, the literature is limited in that the evaluation of this model of care has been only in the UK. It is potentially suited to other settings and needs further evaluation in other settings to assess its utility.

Comparison of outcomes in emergency department patients with suspected cardiac chest pain: two-centre prospective observational study in Southern China

BACKGROUND

Hong Kong (HK) and Guangzhou (GZ) are cities in China with different healthcare systems. This study aimed to compare 30-day and 6-month mortality and characteristics of patients with suspected cardiac chest pain admitted to two emergency departments (ED) in HK and GZ.

METHODS

A prospective observational study enrolled patients with suspected cardiac chest pain presenting to EDs in the Prince of Wales Hospital (PWH), HK and the Second Affiliated Hospital of Guangzhou Medical University (AHGZMU),GZ. The primary outcome was 30-day and 6-month mortality.

RESULTS

In total, 996 patients were recruited, 407 cases from GZ and 589 cases from HK.The 30-day and 6-month mortality of chest patients were 3.7% and 4.7% in GZand 0.3% and 1.9% in HK, respectively. Serum creatinine level (Cr) was an independent factor for 30-day mortality whilst Cr and systolic blood pressure (SBP) were independent factors for 6-month mortality. In Cox regression analysis, unadjusted and adjusted hazard ratios for 30-day and 6-month mortality in GZ were significantly increased.

CONCLUSION

The 30-day and 6-month mortality of patients with suspected cardiac chest pain in Guangzhou were higher than in Hong Kong due to due to different baseline clinical characteristics of patients and different distributions of diagnoses, which were associated with different healthcare systems. Serum creatinine and SBP were independent factors for 30-day and 6-month mortality.

A Rapid Access Chest Pain Clinic (RACPC): Initial Australian Experience

BACKGROUND

Chest pain is the second most common presenting symptom to emergency departments (ED) in Australia, although up to 85% of these patients do not have an acute coronary syndrome (ACS). Cardiologist-led rapid access chest pain clinics (RACPC) have been proposed overseas to assist in the management of such patients, with prompt outpatient assessment if patients are deemed low risk and discharged from the ED. The use of RACPCs in Australia has been only recently proposed; we therefore sought to examine one such RACPC in an Australian context.

METHODS AND RESULTS

1133 consecutive patients were seen at a metropolitan RACPC, between August 2008 and February 2017. There was a high preponderance of cardiovascular risk factors. Exercise stress testing (EST) was the default investigation upon discharge from ED, with a total of 1038 ESTs performed in 1113 patients (93%), with low numbers of other functional tests, and a small, but increasing number of coronary computed tomography (CT) scans performed over this period. Eighteen patients subsequently underwent revascularisation (1.6% of the total cohort), and none of these patients were readmitted at any time with an ACS between the interval of their index ED presentation to these investigations or treatments. Five (0.4%) patients represented to ED within 48hours, none due to a cardiovascular cause. A total of 24 (2.1%) patients represented between 2 and 28 days, with none of these due to an ACS.

CONCLUSIONS

Following ED assessment of acute chest pain as low risk-with direct ED referral for exercising testing followed by RACPC review-results in very low readmission rates at 48hours and at 28 days. Moreover, these readmissions were almost always not of cardiovascular aetiology, and occurred despite relatively longer waiting periods for both EST (8 days) and between EST and RACPC review (11 days), than the prespecified 72 to 96hours as defined by the clinic protocol. Further investigation into this model of care in Australia is suggested.