Prehospital risk assessment and direct transfer to a percutaneous coronary intervention centre in suspected acute coronary syndrome.

OBJECTIVE: Prehospital risk stratification and triage are currently not performed in patients suspected of non-ST-segment elevation acute coronary syndrome (NSTE-ACS). This may lead to prolonged time to revascularisation, increased duration of hospital admission and higher healthcare costs. The preHEART score (prehospital history, ECG, age, risk factors and point-of-care troponin score) can be used by emergency medical services (EMS) personnel for prehospital risk stratification and triage decisions in patients with NSTE-ACS. The aim of the current study was to evaluate the effect of prehospital risk stratification and direct transfer to a percutaneous coronary intervention (PCI) centre, based on the preHEART score, on time to final invasive diagnostics or culprit revascularisation. METHODS: Prospective, multicentre, two-cohort study in patients with suspected NSTE-ACS. The first cohort is observational (standard care), while the second (interventional) cohort includes patients who are stratified for direct transfer to either a PCI or a non-PCI centre based on their preHEART score. Risk stratification and triage are performed by EMS personnel. The primary endpoint of the study is time from first medical contact until final invasive diagnostics or revascularisation. Secondary endpoints are time from first medical contact until intracoronary angiography (ICA), duration of hospital admission, number of invasive diagnostics, number of inter-hospital transfers and major adverse cardiac events at 7 and 30 days. RESULTS: A total of 1069 patients were included. In the interventional cohort (n=577), time between final invasive diagnostics or revascularisation (42 (17-101) hours vs 20 (5-44) hours, p<0.001) and length of hospital admission (3 (2-5) days vs 2 (1-4) days, p=0.007) were shorter than in the observational cohort (n=492). In patients with NSTE-ACS in need for ICA or revascularisation, healthcare costs were reduced in the interventional cohort (€5599 (2978-9625) vs €4899 (2278-5947), p=0.02). CONCLUSION: Prehospital risk stratification and direct transfer to a PCI centre, based on the preHEART score, reduces time from first medical contact to final invasive diagnostics and revascularisation, reduces duration of hospital admission and decreases healthcare costs in patients with NSTE-ACS in need for ICA or revascularisation. TRIAL REGISTRATION: NCT05243485.

Prehospital triage of patients with suspected non-ST-segment elevation acute coronary syndrome: Rationale and design of the TRIAGE-ACS study.

BACKGROUND: Patients with suspected non-ST-segment elevation acute coronary syndrome (NSTE-ACS) are currently transported and admitted to the nearest emergency department (ED) for risk stratification, diagnostic workup and treatment. Although such patients with NSTE-ACS can benefit from direct transfer to a PCI center for early invasive treatment, no reliable prehospital triage tools are available. Recently, the PreHEART score has been validated in the PreHEART study for prehospital triage of patients with suspected NSTE-ACS. METHODS: The primary objective of the TRIAGE-ACS study, a prospective cohort study, is to determine whether prehospital triage using the PreHEART score can significantly reduce time from first medical contact to final diagnostics and revascularization in patients in need of coronary revascularization. The first cohort (control cohort; n = 500) is observatory and is used as a reference group for the second cohort. In the second cohort (interventional cohort; n = 500) patients are stratified in the ambulance for direct transfer to either a PCI or a non-PCI center, based on the PreHEART score. These two cohorts will be compared with each other. In total, 1000 patients will be included. Follow-up for endpoints will be performed by reviewing the medical record after 30 days, 1 year, and 2 years. CONCLUSION: The TRIAGE-ACS study is the first prospective study to investigate the impact of prehospital triage using the PreHEART score on time to final invasive diagnostics and treatment in patients with NSTE-ACS in need of revascularization by transferring high risk patients directly to a PCI center and patients at a low risk of having an NSTE-ACS to a non-PCI center. Such triage strategy could potentially result in optimization of regional care for all ACS patients.

Prehospital risk assessment in patients suspected of non-ST-segment elevation acute coronary syndrome: a systematic review and meta-analysis.

OBJECTIVE: To review, inventory and compare available diagnostic tools and investigate which tool has the best performance for prehospital risk assessment in patients suspected of non-ST-segment elevation acute coronary syndrome (NSTE-ACS). METHODS: Systematic review and meta-analysis. Medline and Embase were searched up till 1 April 2021. Prospective studies with patients, suspected of NSTE-ACS, presenting in the primary care setting or by emergency medical services (EMS) were included. The most important exclusion criteria were studies including only patients with ST-elevation myocardial infarction and studies before 1995, the pretroponin era. The primary end point was the final hospital discharge diagnosis of NSTE-ACS or major adverse cardiac events (MACE) within 6 weeks. Risk of bias was evaluated by the Quality Assessment of Diagnostic Accuracy Studies Criteria. MAIN OUTCOME AND MEASURES: Sensitivity, specificity and likelihood ratio of findings for risk stratification in patients suspected of NSTE-ACS. RESULTS: In total, 15 prospective studies were included; these studies reflected in total 26 083 patients. No specific variables related to symptoms, physical examination or risk factors were useful in risk stratification for NSTE-ACS diagnosis. The most useful electrocardiographic finding was ST-segment depression (LR+3.85 (95% CI 2.58 to 5.76)). Point-of-care troponin was found to be a strong predictor for NSTE-ACS in primary care (LR+14.16 (95% CI 4.28 to 46.90) and EMS setting (LR+6.16 (95% CI 5.02 to 7.57)). Combined risk scores were the best for risk assessment in an NSTE-ACS. From the combined risk scores that can be used immediately in a prehospital setting, the PreHEART score, a validated combined risk score for prehospital use, derived from the HEART score (History, ECG, Age, Risk factors, Troponin), was most useful for risk stratification in patients with NSTE-ACS (LR+8.19 (95% CI 5.47 to 12.26)) and for identifying patients without ACS (LR-0.05 (95% CI 0.02 to 0.15)). DISCUSSION: Important study limitations were verification bias and heterogeneity between studies. In the prehospital setting, several diagnostic tools have been reported which could improve risk stratification, triage and early treatment in patients suspected for NSTE-ACS. On-site assessment of troponin and combined risk scores derived from the HEART score are strong predictors. These results support further studies to investigate the impact of these new tools on logistics and clinical outcome. FUNDING: This study is funded by ZonMw, the Dutch Organisation for Health Research and Development. TRIAL REGISTRATION NUMBER: This meta-analysis was published for registration in PROSPERO prior to starting (CRD York, CRD42021254122).