Objective: Inflammation plays a critical role in the pathogenesis of atherosclerosis. Possible association between C-reactive protein (CRP), stress-induced myocardial ischemia and clinical outcome was investigated.
Design, patients and results: We correlated scintigraphic scan and CRP values of 101 consecutive out-patients who performed an exercise stress test for evaluation of chest pain (n=49) or scheduled control after myocardial infarction (n=52). CRP levels were determined before and after exercise. Twenty-three patients had reversible defects and presented CRP levels [mean (S.D.) 5.6 (3.3) mg/l] greater than subjects with fixed [mean (S.D.) 4.6 (4.5) mg/l] or no [mean (S.D.) 2.8 (2.9) mg/l] defects. Odds ratio for the association between high (3rd, tertile, >4.7 mg/l) CRP levels and reversible defects was 5.6 (95% CI 1.6 to 20; p=0.009). During a follow-up of 2.3 (0.7) years, 18 patients reached a clinical end-point consisting in one Q-wave myocardial infarction, eight non-Q-wave myocardial infarction or unstable angina and nine percutaneous coronary interventions. When the impact of different risk factors on the development of clinical endpoint was evaluated, the hazard ratio associated with high CRP levels was 11.0 (95% CI 3.0 to 41; p<0.001).
Conclusions: These findings suggest that in ambulatory patients, high CRP levels may predict exercise-induced ischemia and patient outcome.