Myocardial Ischaemia After Exposure to Diesel Exhaust (MIDAS)

This study is not yet open for participant recruitment. (see Contacts and Locations)
Verified August 2012 by University of Edinburgh
Sponsor:
Collaborators:
National Institute for Public Health and the Environment, Netherlands
British Heart Foundation
Information provided by (Responsible Party):
University of Edinburgh
ClinicalTrials.gov Identifier:
NCT01661582
First received: August 7, 2012
Last updated: NA
Last verified: August 2012
History: No changes posted
  Purpose

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

Condition Intervention
Coronary Heart Disease
Other: CT/PET Myocardial Perfusion Imaging using O-15 water
Other: Coronary blood flow measured by doppler echocardiography

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary Purpose: Basic Science
Official Title: Myocardial Ischaemia After Exposure to Diesel Exhaust

Resource links provided by NLM:


Further study details as provided by University of Edinburgh:

Primary Outcome Measures:
  • Myocardial blood flow and coronary flow reserve measured by CT/PET O-15 imaging [ Time Frame: Immediately following exposure ] [ Designated as safety issue: No ]
    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:
  • Coronary flow reserve determined using doppler echocardiography [ Time Frame: 1 hour following exposure ] [ Designated as safety issue: No ]
    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 [ Time Frame: Before, 2 and 24 hours following exposure ] [ Designated as safety issue: No ]
    Blood samples will be obtained for measurement of cardiac troponin-I

  • ST segment deviation on continuous 12-lead electrocardiography [ Time Frame: During and for the 24 hours aftet exposure ] [ Designated as safety issue: No ]
    A 12-lead electrocardiogram will be continuously recorded using Holter ECG monitor


Estimated Enrollment: 24
Study Start Date: October 2012
Estimated Study Completion Date: September 2013
Estimated Primary Completion Date: January 2013 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Placebo Comparator: Filtered Air Exposure
Subjects will be exposed to filtered air for 1 hour during intermittent exercise in a purpose-built exposure facility
Other: CT/PET Myocardial Perfusion Imaging using O-15 water Other: Coronary blood flow measured by doppler echocardiography
Experimental: Dilute Diesel Exhaust Exposure
Subjects will be exposed to dilute diesel exhaust (~300 mcg/m3) for 1 hour during intermittent exercise in a purpose-built exposure facility
Other: CT/PET Myocardial Perfusion Imaging using O-15 water Other: Coronary blood flow measured by doppler echocardiography

  Eligibility

Ages Eligible for Study:   18 Years to 60 Years
Genders Eligible for Study:   Male
Accepts Healthy Volunteers:   Yes
Criteria

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
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01661582

Contacts
Contact: Jeremy P Langrish, MB BCh MRCP +441312426428 jeremy.langrish@ed.ac.uk

Locations
United Kingdom
University of Edinburgh / NHS Lothian Not yet recruiting
Edinburgh, United Kingdom, EH16 4SB
Principal Investigator: Jeremy P Langrish, MB BCh MRCP         
Sub-Investigator: Nicholas L Mills, PhD MRCP         
Sub-Investigator: Anoop Shah, MB BCh MRCP         
Sponsors and Collaborators
University of Edinburgh
National Institute for Public Health and the Environment, Netherlands
British Heart Foundation
Investigators
Study Chair: David E Newby, PhD FRCP University of Edinburgh
Principal Investigator: Jeremy P Langrish, MB BCh MRCP University of Edinburgh
  More Information

Publications:
Responsible Party: University of Edinburgh
ClinicalTrials.gov Identifier: NCT01661582     History of Changes
Other Study ID Numbers: MIDAS
Study First Received: August 7, 2012
Last Updated: August 7, 2012
Health Authority: United Kingdom: Research Ethics Committee

Keywords provided by University of Edinburgh:
Air Pollution
Myocardial Ischaemia
Coronary Blood Flow
Diesel Exhaust
Troponin
Electrocardiography

Additional relevant MeSH terms:
Myocardial Ischemia
Coronary Artery Disease
Coronary Disease
Heart Diseases
Ischemia
Cardiovascular Diseases
Vascular Diseases
Arteriosclerosis
Arterial Occlusive Diseases
Pathologic Processes

ClinicalTrials.gov processed this record on July 24, 2014