Author + information
- Matthew Hakimia,b,
- Tomohiko Kisakaa,b,
- Hideya Yamamotoa,b,
- Karlman Wassermana,b and
- Matthew Budoffa,b
Background: Coronary ischemia can be silent or involve the microvascular bed in which the occluding vasculature might not be visible. Physiologic gas exchange data from cardiopulmonary exercise testing (CPET) were correlated with imaging studies for early detection of myocardial ischemia. When myocardial ischemia develops during exercise, it fails to increase O2 extraction per heartbeat above the anaerobic threshold (AT) causing flattening or reduction in VO2/HR (O2-pulse).
Methods: Between 2009 and 2015, 83 subjects (mean age 62.6±13) with no known history of CAD but with risk factors or symptoms underwent CPET followed by coronary CT angiography (CCTA). Studies were performed at the LA Biomedical Research Laboratory (38) and Hiroshima University Hospital in Japan (45). We developed a CPET Algorithm using peak VO2, VE/VCO2 at AT, and delta VO2/delta WR to physiologically separate exercise induced myocardial ischemia (E-IMI) from non-ischemic exercise cardiomyopathy (ECM, related to impaired cardiac mitochondrial biogenesis).
Results: Of 83 individuals who underwent CPET, 31 had normal exercise capacity, 18 were identified as E-IMI and 34 as ECM. On CCTA, 15/18 (83%) of E-IMI patients had severe obstructive CAD. In comparison, 32/34 (94%) in the ECM group had no to mild CAD.
Conclusions: Occlusive CAD can be detected by CPET that further differentiates exercise induced myocardial ischemia from non-ischemic exercise limitation; all with high correlation to the degree of stenosis on CCTA.
Poster Hall, Hall C
Sunday, March 19, 2017, 9:45 a.m.-10:30 a.m.
Session Title: Non Invasive Imaging: Role of Exercise Testing
Abstract Category: 31. Non Invasive Imaging: Sports and Exercise
Presentation Number: 1289-203
- 2017 American College of Cardiology Foundation