Author + information
- Ronnie Ramadan,
- Ibhar Al Mheid,
- Malik Obideen,
- David Sheps,
- Fabio Esteves,
- Viola Vaccarino and
- Arshed Quyyumi
Bone marrow-derived endothelial progenitor cells (EPCs) participate in neoangiogenesis and regeneration in response to tissue ischemia/injury. Reduction in the number of circulating EPCs in patients with cardiovascular (CV) disease is associated with CV risk factors and adverse CV events. We hypothesized that compared to CAD patients without ischemia, those with myocardial ischemia will have more severe CAD but lower numbers of circulating EPCs.
In 140 patients with clinically stable CAD, 99mTc sestamibi myocardial perfusion imaging was used to detect ischemia induced by exercise or adenosine. Baseline number of circulating EPC-enriched population was estimated by the expression of CD34, CD133, and VEGF2R surface antigens on peripheral blood mononuclear cells (CD45medium), using flow cytometry. Angiographic severity of CAD was quantified using the Gensini coronary scoring system. Univariate and multivariate logistic regression models were performed to assess the association between logarithmically transformed EPC counts, Gensini score (GS), and stress induced ischemia.
Ischemia occurred in 30 (21%) patients. Patients with ischemia had higher GS [32(6.75-69.25) vs. 5(0.75-26); p=0.002) suggesting more severe CAD, but lower circulating numbers of triple positive CD34+/CD133+/VEGF2R+ EPCs (p=0.05). After adjustment for age, sex, and established CV risk factors, EPC counts and GS were the only independent predictors for the development of ischemia (B= −0.60, p=0.018; B=1.21, p=0.004, respectively).
A lower circulating number of EPC-enriched cell population is predictive of ischemia in patients with stable CAD, independent of traditional CV risk factors or angiographic CAD severity. Whether this is associated with reduced reparative potential and thus ineffective collateralization that predisposes to ischemia needs to be further investigated. Moreover, whether reduced EPC counts portend a worse long-term outcome needs to be determined.
Poster Sessions, Expo North
Sunday, March 10, 2013, 3:45 p.m.-4:30 p.m.
Session Title: New Tests, Targets and Treatments in SIHD
Abstract Category: 10. Chronic CAD/Stable Ischemic Heart Disease: Clinical
Presentation Number: 1240-72
- 2013 American College of Cardiology Foundation