Long-term Beta-blocker Therapy After Acute Myocardial Infarction

Study Overview
=================
Brief Summary
-----------------
The aim of the study is to determine whether discontinuation of β-blocker after at least 1 year of β-blocker therapy is noninferior to continuation of β-blocker in patients without heart failure (HF) or left ventricular systolic dysfunction after acute myocardial infarction (AMI). Prospective, open-label, randomized, multicenter, noninferiority trial to determine whether discontinuation of β-blocker after at least 1 year of β-blocker therapy is noninferior to continuation of β-blocker in patients without HF or left ventricular systolic dysfunction after AMI.

Detailed Description
-----------------
β-blockers have anti-ischemic, anti-arrhythmic, and anti-adrenergic properties. In order to reduce cardiovascular mortality and morbidity, current major guidelines recommend that oral treatment of β-blockers should be continued during and after hospitalization in patients with acute myocardial infarction (AMI) and without contraindications to β-blocker use. A clinically important but difficult decision on β-blocker therapy after AMI is to determine the duration of β-blocker therapy after discharge in patients without heart failure (HF) or left ventricular systolic dysfunction. Previous studies for long-term β-blocker therapy after AMI were inadequate to derive definite conclusion because of small sample size and potential selection bias. Therefore, the SMART-DECISION trial will investigate whether discontinuation of β-blocker after at least 1 year of β-blocker therapy is noninferior to continuation of β-blocker in patients without HF or left ventricular systolic dysfunction after AMI.

Official Title
-----------------
Discontinuation of β-blocker Therapy in Stabilized Patients After Acute Myocardial Infarction: A Multicenter Randomized Noninferiority Trial

Conditions
-----------------
Myocardial Infarction

Intervention / Treatment
-----------------
* Drug: Discontinuation of β-blocker


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Subject must be at least 19 years of age. Subject who have been continuing β-blocker therapy for at least 1 year after acute myocardial infarction regardless of the time of diagnosis Subject is able to verbally confirm understandings of risks and benefits of this trial, and he/she or his/her legally authorized representative provides written informed consent prior to any study related procedure. Exclusion Criteria: Subject whose left ventricle ejection fraction was less than 40% from echocardiography performed after acute myocardial infarction or who have never received echocardiography. Treatment history of heart failure Contraindication to β-blocker therapy (history of symptomatic bronchial asthma or chronic obstructive pulmonary disease, 2nd or 3rd degree AV block, cardiac pacemaker implantation, or other cases where β-blocker cannot be used under the judgment of the clinician) Non-cardiac co-morbid conditions are present with life expectancy <1 year or that may result in protocol non-compliance (per site investigator's medical judgment). History of atrial fibrillation Pregnancy or breast feeding

Ages Eligible for Study
-----------------
Minimum Age: 19 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: β-blocker discontinuation arm<br>Discontinuation of β-blocker therapy after at least 1 year of β-blocker therapy after acute myocardial infarction | Drug: Discontinuation of β-blocker<br>* Discontinuation of β-blocker after at least 1 year of β-blocker therapy after acute myocardial infarction<br>|
| No Intervention: β-blocker maintenance arm<br>Continuation of β-blocker therapy after acute myocardial infarction | |

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Major adverse cardiac events | a composite of all-cause death, myocardial infarction, hospitalization for heart failure | 2 years after last patient enrollment | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| All-cause death |  | 2 years after last patient enrollment | 
| Cardiac death |  | 2 years after last patient enrollment | 
| Myocardial infarction |  | 2 years after last patient enrollment | 
| Any hospitalization |  | 2 years after last patient enrollment | 
| Hospitalization for heart failure |  | 2 years after last patient enrollment | 
| Hospitalization for acute coronary syndrome |  | 2 years after last patient enrollment | 
| All-cause death or myocardial infarction |  | 2 years after last patient enrollment | 
| Cardiac death or myocardial infarction |  | 2 years after last patient enrollment | 
| Myocardial infarction or hospitalization for heart failure |  | 2 years after last patient enrollment | 
| Any revascularization |  | at 2 years after randomization | 
| Myocardial infarction or any revascularization |  | 2 years after last patient enrollment | 
| Cardiac death, myocardial infarction, or any revascularization |  | 2 years after last patient enrollment | 
| Left ventricle ejection fraction |  | 2 years after last patient enrollment | 
| N-terminal pro-brain natriuretic peptide (NT-proBNP) |  | at 2 years | 
| Atrial fibrillation occurrence |  | 2 years after last patient enrollment | 
| Medical cost | The medical expenses related to heart problems during the follow-up | 2 years after last patient enrollment | 
| PROMIS 29 | PROMIS 29 is composed of a total of 29 questions, and questions are composed of domains for physical function, anxiety, depression, sleep, social function, participation availability, and pain. | 2 years after last patient enrollment | 
| Adverse effects related with β-blocker |  | 2 years after last patient enrollment |