Plasma osteopontin levels, but not its myocardial expression, reflect heart failure severity in recently diagnosed dilated cardiomyopathy.

Background: Elevated levels of the extracellular matrix glycoprotein osteopontin (OPN) may be detected in both myocardium and plasma under various pathological conditions affecting the heart. Several studies demonstrated increased plasma OPN levels in patients with heart failure due to dilated cardiomyopathy (DCM), while other studies showed high OPN expression levels in the myocardium of such patients. However, very little is known about OPN levels in both plasma and myocardium of the same individual with DCM. Therefore, we aimed to compare plasma OPN levels and levels of myocardial OPN expression in patients with recent-onset DCM (Ro-DCM).

Methods: We examined plasma OPN as well as creatinine, C‑reactive protein (CRP), brain natriuretic peptide (BNP), and troponin I levels in 25 patients with Ro-DCM. Furthermore, all subjects underwent transthoracic echocardiography, selective coronary angiography, and endomyocardial biopsy (EMB) for the assessment of myocardial OPN expression.

Results: No significant correlation between myocardial OPN expression and clinical, biochemical, or echocardiographic parameters was found. In log transformation analysis, plasma OPN levels correlated significantly with BNP levels (r = 0.46, p = 0.031), with CRP levels (r = 0.52, p = 0.015), and with early diastolic mitral annular velocity (r = -0.57, p = 0.009). There was a borderline association between the plasma OPN log value and New York Heart Association class (p = 0.053).

Conclusion: Plasma OPN levels reflect heart failure severity in patients with Ro-DCM. Myocardial OPN expression is not associated with either plasma OPN levels or markers of heart failure in these individuals.