Coronary Heart Disease
Conditions
Keywords
Air Pollution, Myocardial Ischaemia, Coronary Blood Flow, Diesel Exhaust, Troponin, Electrocardiography
Brief summary
Exposure to particulate air pollution is associated with increases in cardiovascular mortality and morbidity. The pathophysiological mechanisms underlying this observation are emerging, and exposure to particulate air pollution has been shown to result in increases in blood pressure and arterial tone, impaired vascular function and an increased tendency for blood to clot as well as an increase in atherosclerotic plaque burden. Recent evidence from panel studies and controlled exposure studies have suggested an increase in myocardial ischaemia (a reduction in blood flow to the heart) following exposure. In this study we aim to investigate directly myocardial (heart) blood flow following exposure to diesel exhaust (as a model of urban air pollution) using CT/PET myocardial perfusion imaging in male patients with stable coronary disease and healthy male controls. We hypothesize that following exposure to dilute diesel exhaust: 1. Myocardial blood flow will be reduced 2. Coronary flow reserve will be impaired 3. The magnitude of impairment will be higher in patients with coronary disease as compared to healthy controls
Interventions
OTHERCT/PET Myocardial Perfusion Imaging using O-15 water
OTHERCoronary blood flow measured by doppler echocardiography
Sponsors
National Institute for Public Health and the Environment (RIVM)
British Heart Foundation
University of Edinburgh
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
MALE
Age
18 Years to 60 Years
Healthy volunteers
Yes
Inclusion criteria
* Healthy volunteers will be taking no regular medication, have a normal electrocardiogram and exercise stress test * Patients with a previous history of myocardial infarction or successful coronary revascularization (PTCA or coronary artery bypass grafting) but without symptoms of angina pectoris will be recruited
Exclusion criteria
* Healthy volunteers: * Regular medication * Abnormal 12-lead electrocardiogram * Abnormal exercise stress test * Patients with coronary disease * Acute coronary syndrome within past 3 months * Impaired left ventricular function * Significant valvular heart disease * Left ventricular hypertrophy * Resting conduction defect * Digoxin use * Renal impairment (eGFR \<60 mL/min) * Hepatic impairment * Asthma
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Myocardial blood flow and coronary flow reserve measured by CT/PET O-15 imaging | Immediately following exposure | Myocardial blood flow will be measured at rest and at peak adenosine stress using CT/PET O-15 myocardial perfusion imaging immediately following exposure to diesel exhaust and filtered air |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Coronary flow reserve determined using doppler echocardiography | 1 hour following exposure | Coronary blood flow will be determined in the left anterior descending coronary artery using doppler echocardiography at rest and at peak adenosine stress 1 hour following exposure to diesel exhaust and filtered air |
| Ultra-sensitive cardiac troponin-I | Before, 2 and 24 hours following exposure | Blood samples will be obtained for measurement of cardiac troponin-I |
| ST segment deviation on continuous 12-lead electrocardiography | During and for the 24 hours aftet exposure | A 12-lead electrocardiogram will be continuously recorded using Holter ECG monitor |
Countries
United Kingdom
Outcome results
None listed