Low Risk Acute Coronary Syndrome (LOW ACT)

Stress Testing Versus Non-Stress Testing Based Strategy in Patients Hospitalized With Low-Risk Acute Coronary Syndromes: A Randomized, Single-Center Pilot Study

A large number of patients are diagnosed with low risk ACS, and these individuals are at significant cardiovascular risk. Though guidelines recommend stress testing to manage low risk ACS patients, evidence supporting this recommendation is not based on trials examining this population. A well-designed, randomized trial is warranted to determine if stress testing is useful in managing low risk ACS. If medical therapy alone is equivalent as the investigators hypothesize, healthcare expenditures could be reduced and patients may not be exposed to the harms associated with more invasive cardiac testing such as coronary angiography.

Study Overview

• Status: Completed
• Conditions: Low Risk Acute Coronary Syndrome
• Intervention / Treatment: Procedure: No Stress Test; Procedure: Stress Test

• Study Type: Interventional
• Enrollment (Actual): 70
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Oklahoma
    • Oklahoma City, Oklahoma, United States, 73104
      • Veteran's Affairs Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 30 years to 75 years (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. TIMI score < or = to 2(12)
2. TIMI risk score of 3 with no known CAD, greater than 50% in one or more vessels
3. Normal cardiac biomarkers (3 sets over 12-88 hours)
4. No evidence of acute ischemia on electrocardiograms
5. Normal ejection fraction (>40%) on echocardiography
6. Age 30-75
7. Ability to complete noninvasive stress test
8. Ability to provide informed consent

Exclusion Criteria:

1. Presence of another medical condition to explain chest pain or non-cardiac chest pain (i.e. pneumonia, costochondritis)
2. Any patient who is initially classified as low risk but whom develops recurrent symptoms of ischemia, hemodynamic instability, or arrhythmias attributable to ischemia
3. Evidence of ischemia on electrocardiogram
4. Abnormal cardiac biomarkers
5. History of medical noncompliance or social circumstances preventing compliance
6. Life span estimated at <1 year
7. Pregnancy
8. Refusal to sign consent

Study Plan

How is the study designed?

Design Details

• Primary Purpose: DIAGNOSTIC
• Allocation: RANDOMIZED
• Interventional Model: PARALLEL
• Masking: NONE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: Non-Stress Group; Medical therapy will be implemented and will include the following: aspirin, clopidogrel, b-blockers, and statins. The dosages of aspirin, b-blocker and statin will be left to the discretion of the treating physician. Statins will be initiated irrespective of LDL unless contraindicated. Clopidogrel will be taken for at least one month and ideally up to one year. Sublingual nitroglycerin will be provided to all patients. Other anti-ischemic medications including long-acting nitrates, calcium channel blockers, and ranolazine may be provided at the treating physicians' discretion. If a patient has contraindications to any medications, they will not be administered. If a statin contraindication exists, other cholesterol-lowering medications may be administered. Appendix 4 shows the detailed management of low risk ACS patients randomized to the non-stress group.	Procedure: No Stress Test
ACTIVE_COMPARATOR: Stress Group; Medical therapy will be implemented and will include the following: aspirin, clopidogrel, b-blockers, and statins. Statins will be initiated irrespective of LDL unless contraindicated. Clopidogrel will be taken for at least one month and ideally up to one year. Sublingual nitroglycerin will be provided to all patients. Other anti-ischemic medications including long-acting nitrates, calcium channel blockers, and ranolazine may be provided at the treating physicians' discretion. If a statin contraindication exists, other cholesterol-lowering medications may be administered. All patients will undergo noninvasive stress testing. Results of individual stress tests will be reviewed by a cardiologist. Based on the myocardium deemed at risk and patient symptoms, further testing with angiography and revascularization using percutaneous techniques and/or coronary artery bypass grafting may be considered. Likewise, medical treatment may be adjusted.	Procedure: Stress Test

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Composite of all-cause mortality, hospitalization for UA/NSTEMI or STEMI, and urgent revascularization	Primary endpoints include the composite of all-cause mortality, hospitalization for Unstable Angina/Non ST-Elevation Myocardial Infarction (UA/NSTEMI) or ST-Elevation Myocardial Infarction (STEMI), and urgent revascularization (coronary artery bypass grafting or percutaneous coronary intervention).	one year

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Secondary endpoints will include mortality, UA/NSTEMI or STEMI, coronary revascularization, unplanned diagnostic coronary angiography, noninvasive stress testing, medication adjustments, and medication side effects.	Secondary endpoints will include: mortality, UA/NSTEMI or STEMI, coronary revascularization, unplanned diagnostic coronary angiography, noninvasive stress testing, medication adjustments, and medication side effects.	one year

Collaborators and Investigators

• Sponsor: University of Oklahoma
• Collaborators: VA Office of Research and Development
• Investigators: Principal Investigator: Mazen S Abu-Fadel, MD, FACC, FSCAI, OUHSC and VAMC OKC

Study record dates

Study Major Dates

• Study Start: May 1, 2009
• Primary Completion (ACTUAL): July 1, 2012
• Study Completion (ACTUAL): July 1, 2012

Study Registration Dates

• First Submitted: October 3, 2012
• First Submitted That Met QC Criteria: October 9, 2012
• First Posted (ESTIMATE): October 10, 2012

Study Record Updates

• Last Update Posted (ACTUAL): April 12, 2017
• Last Update Submitted That Met QC Criteria: April 10, 2017
• Last Verified: April 1, 2017

More Information

Terms related to this study

• Keywords: Low Risk ACS, Acute Coronary Syndrome, Stress Testing, Non-Stress Testing
• Additional Relevant MeSH Terms: Pathologic Processes; Myocardial Ischemia; Heart Diseases; Cardiovascular Diseases; Vascular Diseases; Disease; Syndrome; Acute Coronary Syndrome
• Other Study ID Numbers: Low Risk ACS; IRB#14542 (OTHER: University of Oklahoma Health Sciences Center Institutional Review Board)