The relationship between ischaemia burden and exercise time: A CE-MARC sub study (RF_SA_442)

Saturday, February 1, 2025

9:40 AM – 9:50 AM East Coast USA Time

Location: Blue Room PreFunction

Presenting Author(s)

John Greenwood, MBChB, PhD, FRCP, FSCMR, FACC, FESC, FBCS, FICS

Professor/Director
Baker Heart and Diabetes Institute
Melbourne University, Australia

Primary Author(s)

SL

Shaun Leonard, MSc, BSc

Clinical Fellow in Cardiology
West of Scotland Heart and Lung Centre, Golden Jubilee National Hospital, Glasgow, United Kingdom, United Kingdom

Co-Author(s)

Peter P. Swoboda, PhD

Consultant Cardiologist
Leeds Institute of Cardiovascular and Metabolic Medicine, United Kingdom
JY

John Younger, MD

Consultant Cardiologist
Royal Brisbane and Women's Hospital and the University of Queensland, Australia, Australia
NM

Neil Maredia, MD

Consultant Cardiologist
James Cook University Hospital, Middlesburgh, United Kingdom, United Kingdom
Sven Plein, MD PhD

Professor of Cardiovascular Imaging
University of Leeds, United Kingdom
Colin Berry, MD, PhD

Professor of Cardiology
University of Glasgow, United Kingdom
John Greenwood, MBChB, PhD, FRCP, FSCMR, FACC, FESC, FBCS, FICS

Professor/Director
Baker Heart and Diabetes Institute
Melbourne University, Australia

Background: Recent sham-controlled trials have suggested that percutaneous coronary intervention (PCI) has little effect on exercise time in patients with angina ^[1]. We aimed to investigate the relationship between ischaemia burden and exercise capacity in patients with stable angina by using data from Clinical Evaluation of Magnetic Resonance Imaging in Coronary Heart Disease (CE-MARC) ^[2]in which patients underwent stress perfusion cardiovascular magnetic resonance (CMR), treadmill exercise stress testing and quantitative coronary angiography (QCA).

Methods: In this analysis 525 patients with suspected angina and complete data were analysed. Ischaemic segments on CMR were assessed visually by comparing adenosine stress and late gadolinium enhancement images ^[3]. Maximum and cumulative coronary stenosis were measured by QCA. The correlation between exercise time ischaemia burden and QCA findings were assessed by linear regression with correction for clinically important variables which may influence exercise time.

Results:

Baseline patient demographics are summarised in table 1. Mean exercise time was 6 minutes 36 seconds [SD 2 minutes 51 seconds] and energy expenditure was 9.2 METs [SD 3.2 METS]. There were significant negative correlations between exercise time and both ischaemia burden assessed by CMR and number of vessels with significant coronary stenosis (Figure 1).

From CMR data ischaemia burden was also associated with exercise time β -0.20 (95% CI -0.29 to -0.10), even after correction for age, BMI and sex (p < 0.001). From QCA data maximum coronary stenosis β -0.014 (95% CI -0.020 to -0.0082) and cumulative coronary stenosis β -0.0043 (95% CI -0.0063 to -0.0024) are both associated with exercise time, even after correction for age, BMI and sex (p < 0.0001).

Conclusion: Exercise capacity is a strong prognostic indicator in patients with coronary artery disease. This study demonstrates that progressive coronary artery disease reflected by increased ischaemic burden on CMR and QCA is associated with reduced exercise capacity. However, whether reducing ischaemia burden by revascularisation leads to objective improvements in exercise capacity remains an ongoing area of debate.

The severity of coronary artery disease reflected by ischaemic burden on CMR and coronary stenosis by QCA is associated with exercise capacity in patients with stable angina.