Evaluation of Decreased Usage of Betablockers After Myocardial Infarction in the SWEDEHEART Registry (REDUCE-SWEDEHEART)

Randomized Evaluation of Decreased Usage of betablocCkErs After Myocardial Infarction in the SWEDEHEART Registry - A Registry-based, Randomized, Parallel, Open-label, Multicenter Trial (REDUCE-SWEDEHEART)

Long-term beta-blocker therapy has not been investigated in contemporary randomized clinical trials in patients with myocardial infarction and normal heart function. The aim of this study is to determine whether long-term treatment with oral beta-blockade in patients with myocardial infarction and preserved left ventricular systolic ejection fraction reduces the composite of death of any cause or new myocardial infarction..

REDUCE-SWEDEHEART is designed as a registry-based, randomized, parallel, open-label, multicenter trial.

Patients, day 1-7 after myocardial infarction, who have undergone a coronary angiography and with preserved left ventricular systolic ejection fraction will be randomized to either oral beta-blockade (see "Intervention" for detailed description) at a dose according to the treating physician, or no beta-blockade. To allow quick inclusion the randomization module will be accessible by a simple web-based log-in procedure. Concomitantly, all baseline data about each individual patient will be collected from the SWEDEHEART registry. Patients will then be followed regarding all-cause mortality, myocardial infarction, heart failure, atrial fibrillation, and patient-related outcome measures (for a subgroup of patients). Patients that are eligible but not included in REDUCE-SWEDEHEART will also be followed regarding chosen treatment and the primary and secondary endpoints.

Follow-up will continue until 379 primary endpoints have been observed (endpoint driven). All analyses will be performed on the intention-to-treat set, defined as all intentionally randomized patients, by randomized treatment. The primary endpoint is death or new MI. Information about death will be obtained from the Swedish population registry. Information regarding new myocardial infarction during hospitalization and readmission because of myocardial infarction or other outcome (secondary outcomes, see section below), will be obtained from the SWEDEHEART-registry (for myocardial infarction) and the patient registry of the National board of health and welfare.

Inclusion Criteria:

1. Age≥18 years.
2. Day 1-7 after MI as defined by the universal definition of MI, type 1, included in the SWEDEHEART registry.
3. Undergone coronary angiography during hospitalization.
4. Obstructive coronary artery disease documented by coronary angiography, i.e. stenosis ≥ 50 %, FFR ≤ 0.80 or iFR ≤ 0.89 in any segment at any time point before randomization.
5. Echocardiography performed after the MI showing a normal ejection fraction (EF≥50%).
6. Written informed consent obtained.

Exclusion Criteria:

1. Any condition that may influence the patient's ability to comply with study protocol.
2. Contraindications for beta-blockade
3. Indication for beta-blockade other than as secondary prevention according to the treating physician.