ABSTRACT BACKGROUND Point-of-care (POC) high-sensitivity cardiac troponin (hs-cTn) testing has the potential to expedite decision-making and reduce emergency department (ED) length of stay for patients presenting with possible myocardial infarction (MI) by ensuring that results are consistently available when looked for by clinicians. We assessed the real-life effectiveness and safety of implementing POC hs-cTn testing in the ED. METHODS We conducted a pragmatic, stepped-wedge cluster randomized trial. The control arm was usual care with an accelerated diagnostic pathway utilizing a single-sample rule-out step with a central laboratory hs-cTn assay. The intervention arm used the same pathway with a POC hs-cTnI. The primary effectiveness outcome was ED length of stay assessed using a generalized linear mixed model, and the safety outcome was 30-day MI or cardiac death. RESULTS Six sites participated with 59,980 ED presentations (44,747 individuals, 61±19 years, 49.5% female) from February 2023 to January 2025, in which 31,392 presentations were during the intervention arm. After adjustment for co-variates associated with length of stay, the intervention reduced length of stay by 13% (95% confidence intervals [CI], 9 to 16%. P<0.001), corresponding to a reduction of 47 minutes (95%CI, 33 to 61 minutes) from a mean length of stay in the control arm of 376 minutes. The 30-day MI or cardiac death rate was similar in the control and intervention arms (0.39% and 0.39% respectively, P=0.54). CONCLUSIONS Implementation of whole-blood hs-cTnI testing at the POC into an accelerated diagnostic pathway was safe and reduced length of stay in the ED compared with laboratory testing. (Australia New Zealand Clinical Trials Registry ACTRN12619001189112) Clinical Perspective What is new? Point-of-care troponin assays with good precision have become available and received regulatory approval as high-sensitivity assays. A pragmatic stepped-wedge cluster randomized trial implementing the validated Siemens VTLi high-sensitivity point-of-care assay into 6 emergency departments investigating ∼60,000 patients, was conducted to ascertain if the rapid turnaround time reduced lengths of stay. Introduction of the VTLi high-sensitivity point-of-care assay into clinical pathways reduced emergency department lengths of stay by an average 13% (47 minutes) without compromising safety. What are the clinical implications? Early decision-making using a point-of-care high-sensitivity troponin assay within a structured clinical pathway was safe. Faster turnaround means troponin results are consistently available when clinicians first seek them. This can facilitate earlier decisions and reduce patient length of stay.

BACKGROUND:Pathways incorporating clinical risk assessment, ECG and serial troponin measurements for the assessment of patients with possible myocardial infarction (MI) in the ED are standard practice. Incorporating a single troponin test to stratify to low risk of MI using a baseline measurement of cardiac troponin (cTn) with a high-sensitivity T assay (hs-cTnT) is recommended. We aimed to implement a pathway incorporating a single-test component and measure the impact on length of stay (LOS). METHODS:There were two study phases: (1) Development and performance assessment of a novel pathway incorporating a single-test hs-cTnT stratification using high-fidelity research data, (2) An audit of the implementation of a single-test Roche hs-cTnT strategy within multiple EDs. The low-risk threshold used for hs-cTnT was 5 ng/L. The safety metric was MI or death not known to be non-cardiac within 30 days (MACE30). RESULTS:Phase I: The derived pathway had 16.3% low risk after one blood draw ≥3 hours from symptom onset with hs-cTnT <5 ng/L, non-ischaemic ECG and ED Assessment of Chest pain Score <21. PHASE II:In six hospitals, there were 10 912 patients in the control arm and 13 997 after implementation of single-test hs-cTnT. The unadjusted estimated mean reduction in LOS after intervention was 1.6% (95% CI 0.4% to 2.9%). After adjustment accounting for increased presentations, this was 8.5% (95% CI 7.7% to 9.3%). CONCLUSIONS:Within clinical pathways, a single test with a result from an hs-cTnT of <5 ng/L as a component resulted in a small, but meaningful, reduction in mean ED LOS.

Introduction Clinical assessment in emergency departments (EDs) for possible acute myocardial infarction (AMI) requires at least one cardiac troponin (cTn) blood test. The turn-around time from blood draw to posting results in the clinical portal for central laboratory analysers is ~1–2 hours. New generation, high-sensitivity, point-of-care cardiac troponin I (POC-cTnI) assays use whole blood on a bedside (or near bedside) analyser that provides a rapid (8 min) result. This may expedite clinical decision-making and reduce length of stay. Our purpose is to determine if utilisation of a POC-cTnI testing reduces ED length of stay. We also aim to establish an optimised implementation process for the amended clinical pathway.Methods and analysis This quality improvement initiative has a pragmatic multihospital stepped-wedge cross-sectional cluster randomised design. Consecutive patients presenting to the ED with symptoms suggestive of possible AMI and having a cTn test will be included. Clusters (comprising one or two hospitals each) will change from their usual-care pathway to an amended pathway using POC-cTnI—the ‘intervention’. The dates of change will be randomised. Changes occur at 1 month intervals, with a minimum 2 month ‘run-in’ period. The intervention pathway will use a POC-cTnI measurement as an alternate to the laboratory-based cTn measurement. Clinical decision-making steps and logic will otherwise remain unchanged. The POC-cTnI is the Siemens (Erlangen Germany) Atellica VTLi high-sensitivity cTnI assay. The primary outcome is ED length of stay. The safety outcome is cardiac death or AMI within 30 days for patients discharged directly from the ED.Ethics and dissemination Ethics approval has been granted by the New Zealand Southern Health and Disability Ethics Committee, reference 21/STH/9. Results will be published in a peer-reviewed journal. Lay and academic presentations will be made. Māori-specific results will be disseminated to Māori stakeholders.Trial registration number ACTRN12619001189112.

Aims Soluble fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF), components of the vascular endothelial growth factor (VEGF) system, play key roles in angiogenesis. Reports of elevated plasma levels of sFlt-1 and PlGF in coronary heart disease and heart failure (HF) led us to investigate their utility, and VEGF system gene single nucleotide polymorphisms (SNPs), as prognostic biomarkers in HF. Methods and results ELISA assays for sFlt-1, PlGF and N-terminal pro-B-type natriuretic peptide (NT-proBNP) were performed on baseline plasma samples from the PEOPLE cohort (n = 890), a study of outcomes among patients after an episode of acute decompensated HF. Eight SNPs potentially associated with sFlt-1 or PlGF levels were genotyped. sFlt-1 and PlGF were assayed in 201 subjects from the Canterbury Healthy Volunteers Study (CHVS) matched to PEOPLE participants. All-cause death was the major endpoint for clinical outcome considered. In PEOPLE participants, mean plasma levels for both sFlt-1 (125 +/- 2.01 pg/ml) and PlGF (17.5 +/- 0.21 pg/ml) were higher (both p < 0.044) than in the CHVS cohort (81.2 +/- 1.31 pg/ml and 15.5 +/- 0.32 pg/ml, respectively). sFlt-1 was higher in HF with reduced ejection fraction compared to HF with preserved ejection fraction (p = 0.005). The PGF gene SNP rs2268616 was univariately associated with death (p = 0.016), and was also associated with PlGF levels, as was rs2268614 genotype. Cox proportional hazards modelling (n = 695, 246 deaths) showed plasma sFlt-1, but not PlGF, predicted survival (hazard ratio 6.44, 95% confidence interval 2.57-16.1; p < 0.001) in PEOPLE, independent of age, NT-proBNP, ischaemic aetiology, diabetic status and beta-blocker therapy. Conclusions Plasma sFlt-1 concentrations have potential as an independent predictor of survival and may be complementary to established prognostic biomarkers in HF.

We investigated titration patterns of angiotensin-converting enzyme inhibitors (ACEis)/angiotensin receptor blockers (ARBs) and beta-blockers, quality of life (QoL) over 6 months, and associated 1 year outcome [all-cause mortality/heart failure (HF) hospitalization] in a real-world population with HF with reduced ejection fraction (HFrEF). Participants with HFrEF (left ventricular ejection fraction <40%) from a prospective multi-centre study were examined for use and dose [relative to guideline-recommended maintenance dose (GRD)] of ACEis/ARBs and beta-blockers at baseline and 6 months. ‘Stay low’ was defined as <50% GRD at both time points, ‘stay high’ as ≥50% GRD, and ‘up-titrate’ and ‘down-titrate’ as dose trajectories. Among 1110 patients (mean age 63 ± 13 years, 16% women, 26% New York Heart Association Class III/IV), 714 (64%) were multi-ethnic Asians from Singapore and 396 were from New Zealand (mainly European ethnicity). Baseline use of either ACEis/ARBs or beta-blockers was high (87%). Loop diuretic was prescribed in >80% of patients, mineralocorticoid receptor antagonist in about half of patients, and statins in >90% of patients. At baseline, only 11% and 9% received 100% GRD for each drug class, respectively, with about half (47%) achieving ≥50% GRD for ACEis/ARBs or beta-blockers. At 6 months, a large majority remained in the ‘stay low’ category, one third remained in ‘stay high’, whereas 10–16% up-titrated and 4–6% down-titrated. Patients with lower (vs. higher) N-terminal pro-beta-type natriuretic peptide levels were more likely to be up-titrated or be in ‘stay high’ for ACEis/ARBs and beta-blockers ( P = 0.002). Ischaemic aetiology, prior HF hospitalization, and enrolment in Singapore (vs. New Zealand) were independently associated with higher odds of ‘staying low’ (all P < 0.005) for prescribed doses of ACEis/ARBs and beta-blockers. Adjusted for inverse probability weighting, ≥100% GRD for ACEis/ARBs [hazard ratio (HR) = 0.42; 95% confidence interval (CI) 0.24–0.73] and ≥50% GRD for beta-blockers (HR = 0.58; 95% CI 0.37–0.90) (vs. Nil) were associated with lower hazards for 1 year composite outcome. Country of enrolment did not modify the associations of dose categories with 1 year composite outcome. Higher medication doses were associated with greater improvements in QoL. Although HF medication use at baseline was high, most patients did not have these medications up-titrated over 6 months. Multiple clinical factors were associated with changes in medication dosages. Further research is urgently needed to investigate the causes of lack of up-titration of HF therapy (and its frequency), which could inform strategies for timely up-titration of HF therapy based on clinical and biochemical parameters.

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.

OBJECTIVES:This study aimed to examine the concordance of coronary computed tomographic angiography (CCTA) assessment of coronary anatomy and invasive coronary angiography (ICA) as the reference standard in patients enrolled in the ISCHEMIA (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches).BACKGROUND:Performance of CCTA compared with ICA has not been assessed in patients with very high burdens of stress-induced ischemia and a high likelihood of anatomically significant coronary artery disease (CAD). A blinded CCTA was performed after enrollment to exclude patients with left main (LM) disease or no obstructive CAD before randomization to an initial conservative or invasive strategy, the latter guided by ICA and optimal revascularization.METHODS:Rates of concordance were calculated on a per-patient basis in patients randomized to the invasive strategy. Anatomic significance was defined as ≥50% diameter stenosis (DS) for both modalities. Sensitivity analyses using a threshold of ≥70% DS for CCTA or considering only CCTA images of good-to-excellent quality were performed.RESULTS:In 1,728 patients identified by CCTA as having no LM disease ≥50% and at least single-vessel CAD, ICA confirmed 97.1% without LM disease ≥50%, 92.2% with at least single-vessel CAD and no LM disease ≥50%, and only 4.9% without anatomically significant CAD. Results using a ≥70% DS threshold or only CCTA of good-to-excellent quality showed similar overall performance.CONCLUSIONS:CCTA before randomization in ISCHEMIA demonstrated high concordance with subsequent ICA for identification of patients with angiographically significant disease without LM disease.

BACKGROUND:Acute coronary syndrome (ACS) events and the ongoing burden of disease can have a significant impact on the subsequent life-course of working age people. METHODS:We report 12-month clinical outcomes for 10,822 patients hospitalized with first-time ACS between 2015-2016 and enrolled in the All New Zealand Acute Coronary Syndrome Quality Improvement (ANZACS-QI) registry, with a focus on people of working age (defined as <65 years). RESULTS:Nearly half (48%) of first-time ACS occurred in people of working age. Compared to those >65 years, these patients had a high burden of cardiovascular risk factors, and were more likely to be male (75% vs 60%), to be of non-European ethnicity (36% vs 15%), and to be living in areas of high deprivation. Subsequent clinical events were common in the younger patients, with 15% dying or being readmitted for cardiovascular causes within 12 months despite high rates of angiography (96%), revascularization (74%) and evidence-based medical therapy at the time of the index ACS event. CONCLUSIONS:The high risk factor burden and subsequent high rate of clinical events in working age patients reinforces the need for a longer-term focus on strategies to improve clinical outcomes following first-time ACS.

Abstract Objective To determine the association between high flow supplementary oxygen and 30 day mortality in patients presenting with a suspected acute coronary syndrome (ACS). Design Pragmatic, cluster randomised, crossover trial. Setting Four geographical regions in New Zealand. Participants 40 872 patients with suspected or confirmed ACS included in the All New Zealand Acute Coronary Syndrome Quality Improvement registry or ambulance ACS pathway during the study periods. 20 304 patients were managed using the high oxygen protocol and 20 568 were managed using the low oxygen protocol. Final diagnosis of ST elevation myocardial infarction (STEMI) and non-STEMI were determined from the registry and ICD-10 discharge codes. Interventions The four geographical regions were randomly allocated to each of two oxygen protocols in six month blocks over two years. The high oxygen protocol recommended oxygen at 6-8 L/min by face mask for ischaemic symptoms or electrocardiographic changes, irrespective of the transcapillary oxygen saturation (SpO2). The low oxygen protocol recommended oxygen only if SpO2 was less than 90%, with a target SpO2 of less than 95%. Main outcome measure 30 day all cause mortality determined from linkage to administrative data. Results Personal and clinical characteristics of patients managed under both oxygen protocols were well matched. For patients with suspected ACS, 30 day mortality for the high and low oxygen groups was 613 (3.0%) and 642 (3.1%), respectively (odds ratio 0.97, 95% confidence interval 0.86 to 1.08). For 4159 (10%) patients with STEMI, 30 day mortality for the high and low oxygen groups was 8.8% (n=178) and 10.6% (n=225), respectively (0.81, 0.66 to 1.00) and for 10 218 (25%) patients with non-STEMI was 3.6% (n=187) and 3.5% (n=176), respectively (1.05, 0.85 to 1.29). Conclusion In a large patient cohort presenting with suspected ACS, high flow oxygen was not associated with an increase or decrease in 30 day mortality. Trial registration ANZ Clinical Trials ACTRN12616000461493.

A pandemic of Coronavirus-19 disease was declared by the World Health Organization on March 11, 2020. The pandemic is expected to place unprecedented demand on health service delivery. This position statement has been developed by the Cardiac Society of Australia and New Zealand to assist clinicians to continue to deliver rapid and safe evaluation of patients presenting with suspected acute cardiac syndrome at this time. The position statement complements, and should be read in conjunction with, the National Heart Foundation of Australia & Cardiac Society of Australia and New Zealand: Australian Clinical Guidelines for the Management of Acute Coronary Syndromes 2016: Section 2 'Assessment of Possible Cardiac Chest Pain'.

ABSTRACT INTRODUCTIONAccelerated diagnostic chest pain pathways are used widely in urban New Zealand hospitals. These pathways use laboratory-based troponin assays with good analytical precision. Widespread implementation has not occurred in many of New Zealand’s rural hospitals and general practices as they are reliant on point-of-care troponin assays, which are less sensitive and precise. An accelerated chest pain pathway using point-of-care troponin has been adapted for use in rural settings. A pilot study in a low-risk rural population showed no major adverse cardiac events at 30 days. A larger study is required to be confident that the pathway is safe. AIMSTo assess the safety and effectiveness of an accelerated chest pain pathway adapted for rural settings and general practice using point-of-care troponin to identify low-risk patients and allow early discharge. METHODSThis is a prospective observational study of an accelerated chest pain pathway using point-of-care troponin in rural hospitals and general practices in New Zealand. A total of 1000 patients, of whom we estimate 400 will be low risk, will be enrolled in the study. OUTCOME MEASURESThe primary outcome is the proportion of patients identified by the pathway as low risk for a 30-day major adverse cardiac event. Secondary outcomes include the proportion of low-risk patients who were discharged directly from general practice or rural hospitals, the proportion of patients reclassified as having acute myocardial infarction by the pathway and the proportion of patients with low and intermediate risk safely managed in the rural hospital.

The Challenges Rural and remote Australians and New Zealanders have a higher rate of adverse outcomes due to acute myocardial infarction, driven by many factors. The prevalence of cardiovascular disease (CVD) is also higher in regional and remote populations, and people with known CVD have increased morbidity and mortality from coronavirus disease 2019 (COVID-19). In addition, COVID-19 is associated with serious cardiac manifestations, potentially placing additional demand on limited regional services at a time of diminished visiting metropolitan support with restricted travel. Inter-hospital transfer is currently challenging as receiving centres enact pandemic protocols, creating potential delays, and cardiovascular resources are diverted to increasing intensive care unit (ICU) and emergency department (ED) capacity. Regional and rural centres have limited staff resources, placing cardiac services at risk in the event of staff infection or quarantine during the pandemic. Main Recommendations Health districts, cardiologists and government agencies need to minimise impacts on the already vulnerable cardiovascular health of regional and remote Australians and New Zealanders throughout the COVID-19 pandemic. Changes in management should include: Improved access to telehealth consultation for regional and rural outpatients. Specialist-led 24/7 electrocardiograph (ECG) reading and acute cardiology services, uniformly covering all rural inpatients, to minimise potential impacts on acute care. Transfer models incorporating discussion between clinicians and ambulance, balancing urgency with considerations of ambulance capacity in rural locations. Protection of the role of specialist cardiovascular nurses, avoiding COVID-19 redeployment to maintain rural cardiac service capacity. An urgent shift to regional models for pacing services, utilising remote monitoring supported by local device implantation and local technicians.

OBJECTIVE:Ethnic differences in the prevalence of atrial fibrillation (AF) in heart failure (HF) remain unclear. We compared the prevalence and clinical correlates of AF among different ethnicities in an Asian-Pacific population with HF.METHODS:Patients with validated HF were prospectively studied across Singapore and New Zealand (NZ).RESULTS:Among 1746 patients with HF (62% Asian, 26% women, mean age 66 (SD 13) years, mean ejection fraction (EF) 37 (SD 16%), 39% had AF. The prevalence of AF was markedly lower in Singapore-Asians than NZ-Europeans (24% vs 63%; p<0.001), even after adjusting for age, clinical and echocardiographic covariates, regardless of EF group (pinteraction for EF=0.39). Patients with AF were older, had higher body mass index and were more likely to have a history of hypertension, stroke, peripheral vascular disease, renal disease, chronic respiratory disease and increased alcohol intake, but less likely to have diabetes. Clinical correlates were similar for Asians and NZ-Europeans, except diabetes: Asian diabetic patients with HF had less AF compared with Asian patients without diabetes (OR 0.66, 95% CI 0.50 to 0.88), whereas among NZ-Europeans there was no significant association between diabetes and AF (OR 1.22, 95% CI 0.85 to 1.75) (pinteraction for ethnicity=0.01). AF was associated with a higher crude composite outcome of mortality and HF hospitalisations at 2 years (HR 1.19, 95% CI 1.02 to 1.38).CONCLUSION:There is a strikingly lower prevalence of AF among Asian compared with NZ-European patients with HF. The underlying mechanisms for the lower prevalence of AF among Asians, particularly in the presence of diabetes, deserve further study.TRIAL REGISTRATION NUMBER:ACTRN12610000374066.

In New Zealand(NZ)fibrinolysis remains an important treatment for ST elevation myocardial infarction (STEMI). Rescue percutaneous coronary intervention (rPCI), if performed promptly post failed fibrinolytic therapy impacts favourably on clinical outcomes. We report our experience with rPCI over a 2

Background: Rescue percutaneous coronary intervention (rPCI) for ST elevation myocardial infarction (STEMI) is defined as mechanical reperfusion for failed fibrinolysis. Randomised trials on rPCI are characterised by small study populations and major differences in methodology. In particular, there is no consensus on defining the appropriate timing of rPCI for better outcomes. Aim: To determine an appropriate cut off time period for rPCI in STEMI patients with failed thrombolysis that will predict better outcomes. Methods: We performed a retrospective study on STEMI patients with failed thrombolysis managed by rPCI in the Midland region of New Zealand (NZ) between January 2014 and December 2015. Clinical outcomes assessed were mortality and left ventricular ejection fraction (LVEF) at 12 months follow up. Results: A total of 86 patients underwent rPCI with an average age of 62.87 ± 13.24 SD. There were 71 males (82.56%) and 15 females (17.44%). Average time to rPCI post failed thrombolysis was 511.78 ± 50 SD. Total deaths at 1 year was 18 (20.93%). Mean LVEF on follow up was 46.2% ± 12 SD. Mortality correlated significantly with longer time for rescue (p = 0.0008). There was also a significant negative correlation between LVEF and time to rPCI (p < 0.0001). Cut off point of time to rPCI for predicting abnormal LV function (<50%) is 350 minutes. Conclusion: The benefits of rPCI on mortality and LV function diminish with time. Larger studies are needed to compare outcomes in rPCI vs conservative management to define optimal time windows.

Aim: To assess the efficacy, safety and feasibility of implementing an Emergency Department Assessment of Chest Pain Accelerated Diagnostic Pathway (EDACS-ADP) using a current generation point-of-care cardiac troponin (POC cTn) assay for rule-out of acute myocardial infarction in patients presenting to rural General Practices in the Midland region of New Zealand with suspected cardiac chest pain. Method: The EDACS-ADP was implemented and evaluated in twelve rural Midland general practices. The primary outcomes assessed were the number of patients identified as low risk managed without transfer to hospital following presentation and major adverse cardiac events (MACE) (myocardial infarction, death, cardiac arrest, revascularization, shock, arrhythmia,) at 30 days. Results: Between October 2016 and March 2018, 142 patients with chest pain of suspected cardiac origin entered the pathway. 69 (49%) were male, mean age of 56. Over half were considered low risk, managed and discharged home by primary care. Low risk were more likely to be younger (mean age 53 yrs. v 63yrs). No MACE was noted in the low risk group. 1 in 3 patients were assessed as non-low risk and referred to hospital with MACE rate of 15%.Tabled 1Number30 days MACELow Risk80 (56%)0Non Low Risk46(44%)7(15%) Open table in a new tab Conclusion: This rural chest pain pathway has the potential to identify a low risk population who may be safely managed locally thereby reducing transfer to hospital and allowing more rural autonomy, benefiting both patients, and secondary and tertiary health care services.

Background: Efforts to safely reduce length of stay for emergency department patients with symptoms suggestive of acute coronary syndrome (ACS) have had mixed success. Few system-wide efforts affecting multiple hospital emergency departments have ever been evaluated. We evaluated the effectiveness of a nationwide implementation of clinical pathways for potential ACS in disparate hospitals. Methods: This was a multicenter pragmatic stepped-wedge before-and-after trial in 7 New Zealand acute care hospitals with 31332 patients investigated for suspected ACS with serial troponin measurements. The implementation was a clinical pathway for the assessment of patients with suspected ACS that included a clinical pathway document in paper or electronic format, structured risk stratification, specified time points for electrocardiographic and serial troponin testing within 3 hours of arrival, and directions for combining risk stratification and electrocardiographic and troponin testing in an accelerated diagnostic protocol. Implementation was monitored for >4 months and compared with usual care over the preceding 6 months. The main outcome measure was the odds of discharge within 6 hours of presentation Results: There were 11529 participants in the preimplementation phase (range, 284-3465) and 19803 in the postimplementation phase (range, 395-5039). Overall, the mean 6-hour discharge rate increased from 8.3% (range, 2.7%-37.7%) to 18.4% (6.8%-43.8%). The odds of being discharged within 6 hours increased after clinical pathway implementation. The odds ratio was 2.4 (95% confidence interval, 2.3-2.6). In patients without ACS, the median length of hospital stays decreased by 2.9 hours (95% confidence interval, 2.4-3.4). For patients discharged within 6 hours, there was no change in 30-day major adverse cardiac event rates (0.52% versus 0.44%; P=0.96). In these patients, no adverse event occurred when clinical pathways were correctly followed. Conclusions: Implementation of clinical pathways for suspected ACS reduced the length of stay and increased the proportions of patients safely discharged within 6 hours. Clinical Trial Registration: URL: https://www.anzctr.org.au/ (Australian and New Zealand Clinical Trials Registry). Unique identifier: ACTRN12617000381381.

Aim: Prognosis following acute ST elevation myocardial infarction (STEMI) largely relates to the extent of irreversibly damaged myocardium. Imaging techniques are routinely used in clinical practice to estimate infarct size and left ventricular ejection fraction (LVEF). Serum troponin T (TnT), a myocardial contractile protein, is a sensitive biochemical marker for diagnosis of STEMI but there have been limited reports on its ability to predict LVEF. We hypothesise that higher TnT values predict poor LVEF. To determine the utility of serum TnT as a marker to predict impaired LVEF as assessed by echocardiography in patients with first STEMI. Method: A total of 73 patients with first episode of STEMI were identified retrospectively from the Waikato Hospital STEMI database of 2015. Peak TnT levels and LVEF were recorded from the hospital electronic records. LVEF was assessed by Simpson's Biplane method. TnT level was compared to echocardiography LVEF. Results: TnT was found to have a strong negative correlation with LVEF as deduced by the Pearson's correlation coefficient value of -0.504 (p < 0.001) i.e. with increasing levels of TnT there was a decline in LVEF. TnT values >1966 predicted LVEF < 40% (p = 0.028). Conclusion: Peak TnT levels are a simple, inexpensive and non-invasive method to identify patients with impaired LV function of <40% who are at higher risk for adverse cardiovascular outcomes.