Pre-hOspital evaluation of chest Pain patients with sUspected non ST-segment eLevation myocARdial infarction using the HEART-score with a Troponin point-of-care test

Overcrowding in the emergency department is an increasing problem in hospitals
worldwide. Currently, all patients with acute chest pain without ST-segment
elevation on the electrocardiogram (ECG) are transported to the emergency
department in order to rule in or rule out a myocardial infarction.
Point-of-care Troponin (POC cTn) testing in combination with a well
investigated risk stratification tool (HEART-score) used in the ambulance may
contribute to an earlier diagnostic process of ruling in or ruling out
myocardial infarctions and subsequently reduce unnecessary hospital admissions,
total admission time and costs. However, the applicability of the POC cTn and
the HEART-score in the pre-hospital setting remains unclear.

Co-primary Objectives:
1. To assess the interobserver agreement between the pre-hospital HEART-score
calculated by ambulance personnel and the in-hospital HEART-score calculated by
emergency physicians.
2. To evaluate the diagnostic performance of a strategy based on a pre-hospital
HEART-score (with POC cTn testing) or combined with an adjuvant single hs-cTn
test at the emergency department to rule-in or rule-out acute coronary syndrome
(ACS).
3. To evaluate the diagnostic performance of (serial) POC cTn testing or
combined with hs-cTn testing compared to (serial) hs-cTn testing to rule-in or
rule-out MI.
4. To investigate the feasibility of using the pre-hospital HEART-score and POC
cTn in the 0/1 hour algorithm to rule-out ACS.
Secondary Objectives:
5. To evaluate the occurrence of major adverse cardiac events (MACE) in all
included patients with a follow up time of 30 days from first medical contact.
6. To evaluate the patient reported outcome measures (PROMs) in all chest pain
patients transported to the hospital at baseline and at 30 days
7. To perform a cost-analysis of an early diagnostic strategy using the
pre-hospital HEART-score

Study design: A prospective, observational, multicentre study

Study procedures: The HEART-score and the POC cTn will be calculated in all
included patients in the pre-hospital phase. Simultaneously, a venous blood
sample will be drawn from the venous access site for later hs-cTn testing.
Outcomes of any pre-hospital study measurements (i.e. pre-hospital POC cTn
results or calculated pre-hospital HEART-scores) will not affect usual care.
According to current practice, all patients will be transported to the hospital
for further evaluation.

At the emergency department (ED) all included patients will undergo regular
hs-cTn testing and HEART-score assessment performed by emergency physicians
(standard care), and an additional venous bloodsample will be drawn for cTn
measurements. Physicians at the ED are blinded to the outcomes of the POC cTn
tests and pre-hospital HEART-scores.

Follow-up: Total follow-up duration is 30 days after initial presentation.
Other demographic and clinical parameters at baseline will be taken into
account.

All patients will receive a POC cTn test performed by ambulance personnel and a
standard care highly-sensitive troponin at the emergency department. In all
patients, an extra venous blood sample will be drawn from the venous access
site in the pre-hospital phase and venous blood sample will be drawn next to
routine blood testing at the emergency department. Besides the minimal risks of
performing a POC finger prick test, no other risks are involved with study
participation. All patients will be asked to fill in quality-of-life
questionnaires (i.e. SAQ, PHQ-4) at baseline and at follow-up.