The appropriate duration of beta-blocker treatment after a heart attack (a myocardial infarction [MI]) is unknown in patients who do not need to take beta-blockers for another reason. In the ABYSS trial, the cardiovascular safety of interrupting beta-blocker could not be shown in comparison with beta-blocker continuation and beta-blocker interruption did not improve quality of life. ABYSS suggests that long-term beta-blocker therapy is recommended after an MI, even in the absence of heart failure, arrhythmia or uncontrolled hypertension.