Background; Hypertensive myocardial remodeling is the consequence of a number of pathological processes mediated by mechanical and neurohormonal routes. Eccentric hypertrophy and concentric hypertrophy is different remodeling process in terms of fibrosis. We evaluated the usefulness of BNP and Procollagen Peptide Predicting the Presence of Left Ventricular (LV) remodeling in Patients with newly developed hypertension (HTN).
Methods; We measured levels of BNP (Biosite), collagen degradation marker (MMP-1, TIMP-1 and ICTP) and collagen synthesis marker (propeptide of type I or III procollagen: PINP or PIIINP) in 86 patients with newly developed HTN (onset ≤ 1month, without prior medication). LV hypertrophy (LVH) and LV dilatation (LVD) was defined by echocardiography. Normal controls were volunteer without any disease history (group I, n=15). We divided the patients into HTN without LVH (group II, n=21), with LVH (group III, n=22) and with LVD (group IV, n=28, LVEDD >5.5cm). We excluded the patients with heart failure, diabetes, atrial fibrillation, coronary artery disease, renal disease, abnormal liver function and bone or connective tissue disorders.
Results; 1. LVMI (g/m2) were significant differences among groups (group I; 102±22, II; 105±31, III; 146±29, IV; 167±28, p<0.05). BNP were significant differences among groups (17±11, 24±32, 58±39, 198±108 pg/ml, p<0.05). 2. MMP-1, TIMP-1, MMP-1/TIMP-1 ratio and ICTP were significant increased in group II, III and group IV than group I (p<0.05, respectively) and in patients with LVD, MMP-1/TIMP-1 ratio and ICTP were significant increased than in LVH group. PINP and PIIINP were increased in group II, III, IV and, there were no significant difference between LVH and LVD group (p>0.05). 3. Only BNP level was significant difference between group II and group III (p<0.05). The optimal cut-off points for the diagnosis of LVH were 43 pg/ml for BNP (sensitivity 69%, specificity 74%) and 38 ug/l for PINP (sensitivity 59%, specificity 51%). Only 1of 38 patients with values of BNP and PINP less than the optimal cut-off point had echocardiographic LVH, resulting in a high negative predictive value of 97% for the 2 blood tests combined to exclude LVH. 4. In LVD, the accuracy using a cut-off value were 0.83 at BNP 121 pg/ml (p= 0.001) and LVD had a significant correlation with MMP-1 (r=0.312, p<0.05), MMP-1/TIMP-1(r=0.362, p<0.05) and ICTP (r=0.309, p<0.05). Conclusion; Our results suggest that BNP and serum markers of collagen degradation may act as LV remodeling process. In hypertensive heart disease, especially, LVH can be excluded on the basis of blood sample for the determination of BNP and PINP.
|
