Background: Inflammation is an important mechanism in atherosclerosis and plaque formation. C-reactive protein (CRP) is a common inflammatory biomarker associated with the risk of coronary heart disease. We investigated the relationship of CRP with findings from myocardial perfusion imaging (MPI).
Methods: In this retrospective study, 102 consecutive patients (mean age 71 years, 68% males) who underwent MPI (for diagnostic reasons or quantification of myocardial ischemia) and CRP determination (upper limit: 6 mg/L) within 1 month from MPI were included. The patients had no infection or recent acute coronary syndrome.
Results: The median CRP level was 4 mg/L (2, 10) among the study population. Patients with raised CRP had higher summed stress score (SSS) (p = 0.006) and summed rest score (SRS) (p = 0.001) and higher risk for SSS > 3 (OR 9.25, 95% CI 2.03-42.13, p = 0.001) compared to those with low CRP. The association of SSS and SRS with CRP levels was more evident in patients over 70 years (p = 0.027 and p = 0.005, respectively). No significant difference in summed difference score was shown. The two groups had no difference in other risk factors (p > 0.05 for all comparisons).
Conclusion: a high level of CRP was associated with the presence and extent of stress-induced myocardial ischemia in MPI.
Keywords: C-reactive protein; SPECT; cardiac imaging; ischemia; myocardial perfusion imaging.