Abstract 2997: Usefulness of B-Type Natriuretic Peptide and Procollagen Peptide Predicting the Presence or Absence of Left Ventricular Hypertrophy in Patients with Hypertension
Background : Interstitial fibrosis and neurohormonal marker are suggested to contribute to left ventricular hypertrophy (LVH). We evaluated the relationship between B-type natriuretic peptide (BNP) or procollagen markers and LVH, and tested the hypothesis whether procollagen peptide and BNP would be useful to predict echocardiographic LVH.
Method : Baseline blood samples were collected at entry from 96 patients (hypertension 83, control 13) with newly developed hypertension without prior medications. We measured serum levels of BNP (Biosite), and collagen synthesis marker (propeptide of type I or III procollagen: PINP or PIIINP, Orion) in patients LVH was defined by echocardiography. We excluded the patients with diabetes, atrial fibrillation, coronary artery disease, renal disease, abnormal liver function, bone or connective tissue disorders, obesity and suspicious heart failure.
Results : In all hypertension patients (age=63, male 63%), median values of the peptides were BNP 36 pg/ml (5 – 118), PIIINP 2.6 (1.4 – 5.8) ug/l and PINP 32 (16 – 96) ug/l. 38 patients (39.6%) had echocardiographic LVH. Patients with LVH were significantly older and had higher PINP, PIIINP and BNP concentrations and higher systolic blood pressure (p<0.05). BNP (p<0.018) and PINP (p<0.043) were the biochemical parameters that independently predicted left ventricular mass index. The sensitivity and specificity of ECG (Sokolow-Lyon criteria) for LVH detection was 32% and 79%, respectively. The optimal cut-off points for the diagnosis of LVH were 43 pg/ml for BNP (sensitivity 69%, specificity 74%), 38 ug/l for PINP (sensitivity 59%, specificity 51%) and 3.2 ug/l for PIIINP (sensitivity 42%, specificity 46%). Only 2 of 38 patients with values of BNP and PINP less than the optimal cut-off point had echocardiographic LVH, resulting in a high sensitivity value of 94.7% and specificty of 93.3% for the 2 blood tests combined to exclude or predict LVH.
Conclusion : In hypertensive patients, echocardiographic LVH was related with BNP and procollagens levels, and can be predicted or excluded on the basis of blood sample for the determination of BNP and PINP.