Assessing the Haemodynamic Effects of Extrinsic Coronary Stenoses
Research type
Research Study
Full title
Phasic haemodynamics of extrinsic and intrinsic coronary stenoses during exercise: an invasive and imaging study of anomalous coronaries, myocardial bridges and atherosclerotic coronary stenoses
IRAS ID
257883
Contact name
Ricardo Petraco
Contact email
Sponsor organisation
Imperial College London
Duration of Study in the UK
2 years, 0 months, 0 days
Research summary
A small but significant proportion of patients have coronary arteries which take abnormal courses, either between the main arteries that leave the heart (inter-arterial course) or through the heart muscle (intra-myocardial bridging). These are collectively referred to as 'extrinsic stenoses', distinct from the more commonly understood typical 'intrinsic stenoses' caused by the build up of plaque within the coronary arteries. Patients with extrinsic stenoses are at an increased risk of chest pain, heart attack, dangerous heart rhythms and sudden cardiac death. However, the mechanism through which these anomalies cause problems is not well understood. These studies have undertaken assessment of these coronary arteries using both non-invasive (ultrasound and MRI) and invasive (coronary pressure wire) techniques. These studies have also simulated exercise using a drug to inducea fast heart beat. This study will be the first to use true exercise during assessment, using a table-mounted exercise bike. Our pilot data has established significant differences in coronary haemodynamics during drug-induced stress compared with true exercise. We have also established that in those patients where the coronary artery dives into the heart muscle itself (muscle bridges) which also causes extrinsic compression, conventional coronary pressure wire testing using adenosine does not reliably reveal the true haemodynamics of the bridged artery, compared with the use of dobutamine. Our study will use bike exercise to collect invasive physiological and non-invasive echocardiographic data in patients with anomalous coronary arteries and myocardial bridges, and compare these to patients with intrinsic stenoses from coronary artery disease, thereby providing a mechanistic link between extrinsic stenoses and cardiac events.
REC name
London - Brent Research Ethics Committee
REC reference
20/LO/1166
Date of REC Opinion
26 Nov 2020
REC opinion
Further Information Favourable Opinion