The Effects of Diesel Exhaust Inhalation On Exercise Capacity In Patients With Stable Angina Pectoris

Study Overview
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Brief Summary
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The purpose of this study is to determine whether exposure to diesel exhaust (air pollution) has a functional impact on patients with stable angina pectoris.

Detailed Description
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Air pollution is a major cause of cardiovascular morbidity and mortality. The mechanism and components of air pollution responsible for these cardiovascular effects are unknown but small combustion-derived particles are suspected to be the major cause. Using a unique exposure system in Umeå Sweden, we have demonstrated that healthy volunteers who inhale dilute diesel exhaust develop an impairment of two important, highly relevant and complementary aspects of vascular function: the regulation of vascular tone and endogenous fibrinolysis. We have recently extended these findings and have shown that brief exposure to dilute diesel exhaust promotes myocardial ischemia and inhibits endogenous fibrinolytic capacity in patients with stable asymptomatic coronary heart disease. We now wish to extend these findings to patients with chronic stable angina pectoris. In particular, we wish to determine the functional impact of diesel exhaust inhalation as well as describe the time course and minimum exposure that can induce these detrimental effects.

Official Title
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The Effects of Diesel Exhaust Inhalation On Exercise Capacity In Patients With Stable Angina Pectoris

Conditions
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Coronary Heart Disease, Angina Pectoris

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Documented coronary heart disease Symptoms of stable angina pectoris Exclusion Criteria: History of arrhythmia Severe 3 vessel coronary artery disease or left main stem stenosis that has not been revascularised Resting conduction abnormality Digoxin therapy Uncontrolled hypertension Renal or hepatic failure Patients with unstable disease (ACS or unstable symptoms within 3 months) Asthma Intercurrent illness
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 documented stable coronary artery disease, symptoms of stable angina pectoris, and a positive standard BRUCE exercise stress test at 3 - 13 minutes. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Myocardial ischaemia - measured as time to 1mm ST segment depression on the ECG during standard BRUCE exercise stress testing. |  | Immediately after exposure | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Total ischaemic burden - assessed using 24 hour Holter ambulatory ECG monitoring |  | 24hrs after exposure | 
| Total exercise capacity - assessed by maximal work done during exercise stress test |  | Immediately after exposure | 
| Biochemical evidence of myocardial ischaemia - plasma highly sensitive troponins, ischaemically modified albumin, fatty acid binding protein |  | Before, after and at 24 hours after exposure | 

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