Very Early veRsus Deferred Invasive Evaluation Using Computerized Tomography in Patients With Acute Coronary Syndromes

The aim of this study is to evaluate if acute invasive coronary evaluation and treatment conducted within 12 hours of diagnosis improves clinical outcome compared to a deferred, subacute strategy in patients with unstable angina pectoris (UAP) / non-ST segment elevation myocardial infarction (NSTEMI) Acute coronary syndrome (ACS) Furthermore, in an observational design the potential clinical benefit of coronary computed tomography angiography (CCTA) to select patients for invasive investigation and treatment in the two treatment arms (acute vs deferred) is evaluated.

The following main hypothesis will be tested:

* Very early invasive coronary investigation improves clinical outcome in patients with UAP/NSTEMI-ACS
* CCTA performed before invasive coronary investigation will improve clinical management of patients with UAP/NSTEMI-ACS

MATERIAL Consecutive patients suspected of UAP/NSTEMI will be screened for participation in the study. Only patients deemed clinically suited for invasive coronary evaluation and treatment will be included. A total of 2500 patients will be included in the trial at Departments of Cardiology of Danish Hospitals.

METHODS If the patients accept participation in the trial a computerized 1:1 randomization for acute invasive coronary evaluation (Intervention group - within 12 hours from time of diagnosis) or for deferred invasive evaluation (Control group - no later than 72 hours from time of diagnosis). All included patients undergo CCTA prior to invasive coronary evaluation, except for patient with moderately reduced renal function (se below). The treating invasive cardiologist will remain blinded to observational CCTA data. Patients with endstage renal disease in dialysis may undergo CCTA. CCTA data recorded as part of the research protocol will not be made available for the treating physician.

SECONDARY EXCLUSION Based on post-hoc expert clinical evaluation patients not having UAP/NSTEMI-ACS (arrythmias, pulmonary oedema, missed STEMI, pneumonia, Pulmonary emboli) will be excluded from analysis of difference between outcome measures in treatment strategy groups.

STATISTICAL METHODS Patients with UAP/NSTEMI-ACS are based on previous studies expected to have an event rate of 15% within 1 year and 50% at 4 years of the primary combined endpoint: all cause mortality, non-fatal recurrent myocardial infarction, hospitalisation for refractory ischemia or heart failure. In order to demonstrate a reduction of 25% within 3 years 711 patients in each group are needed. The study is powered to detect a clinical relevant reduction in mortality or heart failure hospitalization with a total of 2500 patients.

Eligibility Criteria:
Inclusion Criteria:

Patients with clinical suspicion of of UAP/NSTEMI acute coronary syndrome deemed suitable for invasive evaluation and treatment will be included in the study.

* Age\> 18 years
* At least one of the following:
* ECG abnormalities suggestive of myocardial ischemia (newly developed ST segment depression, horizontal or descending \>= 0,05mV in two anatomically adjacent leads and/or T-wave inversion \>0,01 mV in two leads with prominent R wave or R/S ratio \>1
* Elevated myocardial ischemia biomarkers (Troponin, CK-MB)

Exclusion Criteria:

* Pregnancy
* Circumstances preventing the patient from reading and/or understanding the research protocol information
* Clinical indication for acute invasive coronary angiography - severe chest pain despite intravenous nitroglycerin infusion or hemodynamic instability
* Expected survival of less than 1 year
* Known allergy/hypersensitivity of pharmacological platelet inhibitors and/or iodine contrast that cannot be prevented medically

Patients with known eGFR below 60 ml/min will not undergo CCTA, whereas patients in dialysis will undergo the entire study protocol