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Asymptomatic Cardiac Ischemia Pilot (ACIP) Study

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ClinicalTrials.gov Identifier: NCT00000478
Recruitment Status : Completed
First Posted : October 28, 1999
Last Update Posted : March 25, 2016
Information provided by:
National Heart, Lung, and Blood Institute (NHLBI)

Brief Summary:
To assess the feasibility of and test the methodology for a full-scale clinical trial of therapies for asymptomatic cardiac ischemia.

Condition or disease Intervention/treatment Phase
Cardiovascular Diseases Coronary Disease Heart Diseases Myocardial Ischemia Drug: atenolol Drug: nifedipine Drug: diltiazem Drug: isosorbide dinitrate Procedure: coronary artery bypass coronary artery bypass Procedure: angioplasty, transluminal, percutaneous coronary Phase 3

Detailed Description:


Asymptomatic cardiac ischemia, frequently designated as silent myocardial ischemia, refers to episodes of objectively demonstrable transient ischemia in the absence of symptoms. Annually, more than one million patients suffer acute myocardial infarction. Of the approximately 700,000 who are discharged alive from the hospital, as many as 180,000 will be asymptomatic but have evidence of myocardial ischemia on a pre-discharge exercise test. Asymptomatic ischemia has been linked with sudden death or myocardial infarction. It is estimated that in the United States over six million patients have chronic, symptomatic coronary heart disease and up to three million of these may exhibit transient asymptomatic myocardial ischemia. Asymptomatic ischemia is thought to be present in the majority of coronary heart disease patients with stable angina pectoris, over 70 percent of all ischemic episodes being asymptomatic. Asymptomatic ischemia following myocardial infarction or in the presence of chronic stable angina may be associated with substantially increased morbidity and mortality

Traditionally, treatment of patients with coronary heart disease has been given for and guided by patients' symptoms. There was a growing trend toward recognizing asymptomatic cardiac ischemia and according it importance equal to that of symptomatic ischemia. Many physicians believed that suppression of asymptomatic ischemia in patients with coronary heart disease would reduce morbidity and mortality. This was leading to rapidly increasing and widespread applications of both medical and revascularization therapies.

In 1989, there was a lack of knowledge as to the relative efficacy of different treatment strategies to control asymptomatic cardiac ischemia. Given the estimated high prevalence of asymptomatic cardiac ischemia in patients with coronary heart disease and evidence of increased risk of untoward outcome, the public health problem was of sufficient magnitude to warrant a pilot study to determine to what extent asymptomatic ischemia could be controlled. If the pilot study demonstrated feasibility, a full-scale clinical trial would then be considered to evaluate the impact of effective treatment of asymptomatic ischemia on survival and cardiovascular morbidity in patients with coronary heart disease.


A total of 1,959 patients were screened by AECG monitoring; 49 percent had asymptomatic ischemia, and 65 percent were enrolled in the study. The 618 patients were randomized to one of the three treatment strategies: 202 to angina-guided medical strategy with titration of anti-ischemic medication to relieve angina; 202 to angina-guided plus AECG ischemia-guided medical strategy with titration of anti-ischemic medication to eliminate both angina and AECG ischemia; and 212 to revascularization by angioplasty or bypass surgery. Patients able to take either beta-adrenergic blocking agents or calcium antagonists were also randomized to receive one of two medical combination regimens: atenolol plus nifedipine or diltiazem plus isosorbide dinitrate. Those who could be treated with only one regimen, such as asthmatic patients, were assigned to the appropriate regimen. The primary outcome was the absence of ischemia at twelve weeks. Recruitment ended in January 1993. Clinical based follow-up was completed for 18 months and survival status free of MI was completed for 24 months

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Study Type : Interventional  (Clinical Trial)
Allocation: Randomized
Primary Purpose: Treatment
Study Start Date : November 1990
Study Completion Date : June 1997

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 75 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Men aand women with angiographically documented coronary artery disease, ischemia on both stress (exercise) testing and 48-hour ambulatory electrocardiogram monitoring, and who were amenable to revascularization.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00000478

Sponsors and Collaborators
National Heart, Lung, and Blood Institute (NHLBI)
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OverallOfficial: Jerome Cohen St. Louis University
OverallOfficial: Richard Davies University of Ottawa
OverallOfficial: John Deanfield St. Bartholomew's Hospital, University of London
OverallOfficial: Mark Ketterer Henry Ford Hospital
OverallOfficial: Genell Knatterud
OverallOfficial: Hiltrud Mueller Montefiore Medical Center
OverallOfficial: Pamela Ouyang Johns Hopkins University
OverallOfficial: Carl Pepine University of Florida
OverallOfficial: Craig Pratt Baylor College of Medicine
OverallOfficial: William Rogers University of Alabama at Birmingham
OverallOfficial: Andrew Selwyn Brigham and Women's Hospital
Study Data/Documents: Individual Participant Data Set  This link exits the ClinicalTrials.gov site
Identifier: ACIP
NHLBI provides controlled access to IPD through BioLINCC. Access requires registration, evidence of local IRB approval or certification of exemption from IRB review, and completion of a data use agreement.


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ClinicalTrials.gov Identifier: NCT00000478    
Other Study ID Numbers: 67
First Posted: October 28, 1999    Key Record Dates
Last Update Posted: March 25, 2016
Last Verified: February 2002
Additional relevant MeSH terms:
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Cardiovascular Diseases
Heart Diseases
Coronary Disease
Myocardial Ischemia
Pathologic Processes
Vascular Diseases
Isosorbide Dinitrate
Calcium Channel Blockers
Membrane Transport Modulators
Molecular Mechanisms of Pharmacological Action
Calcium-Regulating Hormones and Agents
Physiological Effects of Drugs
Vasodilator Agents
Tocolytic Agents
Reproductive Control Agents
Anti-Arrhythmia Agents
Antihypertensive Agents
Autonomic Agents
Peripheral Nervous System Agents
Adrenergic beta-1 Receptor Antagonists
Adrenergic beta-Antagonists
Adrenergic Antagonists
Adrenergic Agents