Effects of Ambient Air Pollution Exposure in Patients With Stable Angina Pectoris During Normal Daily Activities

Study Overview
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Brief Summary
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The purpose of this study is to identify whether exposure to ambient levels of air pollution during normal daily activities has a functional impact on patients with coronary heart disease

Detailed Description
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Exposure to air pollution has been shown in epidemiological studies to be closely linked to cardiovascular morbidity and mortality. The exact components of air pollution that underlie the cardiovascular effects are not yet known, but combustion-derived particulate matter is suspected to be the major cause. In controlled exposure studies, we have recently demonstrated that exposure to diesel exhaust causes increased myocardial ischaemia with exercise in patients with asymptomatic coronary artery disease. The mechanism behind this effect is not yet understood, but we have shown that diesel exhaust exposure causes an acute impairment of two important and highly relevant aspects of vascular tone: vasomotor tone and endogenous fibrinolysis. In this study we propose to investigate the effects of exposure to ambient levels of air pollution on patients with stable, symptomatic angina pectoris, during their daily lives.

Official Title
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Effects of Ambient Air Pollution Exposure in Patients With Stable Angina Pectoris During Normal Daily Activities

Conditions
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Angina Pectoris, Coronary Heart Disease

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Documented coronary artery disease Symptoms of stable angina pectoris Positive BRUCE exercise stress test between 3 and 13 minutes Exclusion Criteria: History of arrhythmia Severe 3 vessel coronary disease or left main stem stenosis that has not been revascularised Resting conduction abnormality Digoxin therapy Uncontrolled hypertension Renal or hepatic failure Unstable symptoms or acute coronary syndrome within 3 months
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| 1<br>Patients with stable angina pectoris and documented coronary heart disease recruited in Edinburgh | |
| 2<br>Patients with stable angina pectoris and documented coronary heart disease recruited in London | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Symptoms of angina pectoris - assessed by symptom diary and reliever medication usage |  | Throughout study period | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Myocardial ischaemic burden - assessed using 12-lead continuous Holter ECG monitoring |  | Throughout study period | 
| Time to 1mm ST segment depression during standard BRUCE exercise stress testing |  | At the end of the study period | 
| Total exercise capacity - measured using GPS tracking of activity completed |  | Throughout study period | 
| Exercise capacity - determined by standard BRUCE exercise stress testing |  | Immediately after study period | 
| Ambulatory blood pressure |  | Throughout study period | 
| Biochemical evidence of myocardial ischaemia - highly sensitive troponin, ischaemically modified albumin and fatty acid binding protein |  | Before and after study period | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Angina pectoris, Exercise capacity, Myocardial ischaemia, Air pollution