Myocardial Ischaemia After Exposure to Diesel Exhaust
- Conditions
- Coronary Heart Disease
- Interventions
- Other: CT/PET Myocardial Perfusion Imaging using O-15 waterOther: Coronary blood flow measured by doppler echocardiography
- Registration Number
- NCT01661582
- Lead Sponsor
- University of Edinburgh
- 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
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- Male
- Target Recruitment
- 28
- 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
- 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
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- CROSSOVER
- Arm && Interventions
Group Intervention Description Dilute Diesel Exhaust Exposure CT/PET Myocardial Perfusion Imaging using O-15 water Subjects will be exposed to dilute diesel exhaust (\~300 mcg/m3) for 1 hour during intermittent exercise in a purpose-built exposure facility Filtered Air Exposure CT/PET Myocardial Perfusion Imaging using O-15 water Subjects will be exposed to filtered air for 1 hour during intermittent exercise in a purpose-built exposure facility Filtered Air Exposure Coronary blood flow measured by doppler echocardiography Subjects will be exposed to filtered air for 1 hour during intermittent exercise in a purpose-built exposure facility Dilute Diesel Exhaust Exposure Coronary blood flow measured by doppler echocardiography Subjects will be exposed to dilute diesel exhaust (\~300 mcg/m3) for 1 hour during intermittent exercise in a purpose-built exposure facility
- Primary Outcome Measures
Name Time Method 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 Outcome Measures
Name Time Method 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
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
Trial Locations
- Locations (1)
University of Edinburgh / NHS Lothian
🇬🇧Edinburgh, United Kingdom