Characterization of Myocardial Blood Flow During Heat Exposure

Healthy Clinical Trial

— PET-Heat  

Official title:

Characterization of the Increase and Distribution of Myocardial Blood Flow During Heat Exposure

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT04549974
• Other study ID #: ICM 2020-2719
• Status: Completed
• Phase: N/A
• Start date: August 25, 2020
• Est. completion date: March 31, 2023

Study information

• Verified date: May 2023
• Source: Montreal Heart Institute
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The purpose of this study is to determine the increase in myocardial blood flow during heat exposure and how this response is affected by age and coronary artery disease.

Description:

As a result of climate change, heat waves are more frequent and of longer duration. These heat waves are associated with a higher risk of hospitalization and mortality in vulnerable populations such as people with cardiovascular disease or cardiovascular risk factors. It has been hypothesized that this observation may be explained by the cardiovascular demands imposed by heat exposure.

Heat exposure requires increased cardiac work that may place individuals with cardiovascular disease at risk of ischemic events if the metabolic demand is not compensated by adequate blood supply. However, the extent to which cardiac work increases during heat exposure remains unknown. The aim of this study is to test the hypothesis that heat exposure increases myocardial blood flow and that this increase is affected by age and coronary artery disease.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 80
• Est. completion date: March 31, 2023
• Est. primary completion date: March 31, 2023
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 80 Years

Eligibility

Inclusion Criteria for Healthy Participants:

• Age between 18-40 years or 60-80 years

• Non-smoker (=1 year)

• Non-diabetic

• Normal kidney function

• Body Mass Index <30 kg/m2

• Resting blood pressure <140/<90 mmHg

• Resting heart rate <100 bpm

Inclusion Criteria for Participants with Coronary Artery Disease:

• Age between 60-80 years old

• History of angiographic coronary disease (=70% arterial diameter narrowing of at least one major epicardial coronary artery) and/or prior coronary revascularization and/or documented prior acute coronary syndrome and/or perfusion defect during stress testing

• Stable medications (=4 weeks) prior to enrollment

Exclusion Criteria for Healthy Participants:

• Diagnosis of heart, vascular, respiratory, neurological or metabolic disease and/or a prescription of medication for the treatment of these diseases

• Pregnancy or lactation

• Dyslipidemia not controlled by medication

Exclusion Criteria for Participants with Coronary Artery Disease:

• Recent hospitalization (<3 months) related to coronary artery disease

• Unstable angina (<3 months)

• Recent coronary artery bypass surgery (<3 months)

• Left branch block

• Ejection fraction <40% and/or clinical signs of heart failure

• Severe valvular heart disease

• Hypertension not controlled by medication

• Diabetes not controlled by medication and/or serious complications related to diabetes

Related Conditions & MeSH terms

• Aging
• Coronary Artery Disease
• Healthy
• Hot Weather; Adverse Effect

Intervention

Other:
• Heat exposure
Participants will be exposed to heat exposure via a water-perfused suit to increase internal body temperature by 1.5 degrees Celsius.

Locations

Country	Name	City	State
Canada	Montreal Heart Institute	Montréal	Quebec

Sponsors (1)

Lead Sponsor	Collaborator
Montreal Heart Institute

Country where clinical trial is conducted

Canada, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Global myocardial blood flow	Measured by PET imaging with 82rubidium	Change from baseline to an increase in internal body temperature of 1.5 degrees Celsius, estimated average = 90 minutes
Secondary	Myocardial blood flow distribution	Measured by PET imaging with 82rubidium	Change from baseline to an increase in internal body temperature of 1.5 degrees Celsius, estimated average = 90 minutes
Secondary	Heart rate	Measured by electrocardiogram	Change from baseline to an increase in internal body temperature of 1.5 degrees Celsius, estimated average = 90 minutes
Secondary	Systolic and diastolic blood pressure	Measured by automated auscultation of the brachial artery	Change from baseline to an increase in internal body temperature of 1.5 degrees Celsius, estimated average = 90 minutes
Secondary	Body weight	Measured with a scale	Measured before and after heat exposure, estimated average = 120 minutes