Effects Of Percutaneous Balloon Mitral Valvuloplasty On Plasma B-type Natriuretic Peptide In Rheumatic Mitral Stenosis Patients

Background and aim of the study This study was designed to evaluate the effect of percutaneouse balloon mitral valvuloplasty (PBMV) on plasma B-type natriuretic peptide (BNP) levels in patients in sinus rhythm (SR) and with atrial fibrillation (AF). Methods 30 patients with rheumatic mitral stenosis (MS) successfully underwent PBMV were included in this study. 21 patients were in SR and 9 had AF. Plasma BNP concentrations were measured by the Triage BNP Test in all patients before, at 20 minutes and 24 hours after PBMV, and in eight healthy volunteers.Results Basal plasma BNP levels in patients were significantly higher than those in the control group (123.55+/-69.49pg/ml vs. 16.39+/-7.64pg/ml, P< 0.01), and it was correlated with mean left atrial pressure and pulmonary artery pressure (mLAP r=0.441,/)<0.05; PAP r=0.488,P<0.01). No difference was observed in BNP levels between patients in SR and with AF (P>0.05). In SR patients, BNP levels decreased after PBMV (before, 128.66+/-75.96pg/ml; at 20 minutes, 88.58+/-61.99pg/ml; at 24 hours, 43.39+/-26.70pg/ml; respectively, P<0.05). There were positive correlations between changes in plasma BNP (ABNP) and changes in mLAP (AmLAP)(r=0.696,P<0.01) as well as in PAP (APAP)(r=0.456,P<0.05). Left ventricular end-diastolic volume (LVEDV)(96.14+/-21.59ml vs. 111.46+/-25.18ml, P<0.01) and stroke volumes (SV)(59.19+/-15.75ml vs. 68.98+/-17.88ml, P<0.05) augmented accordingly without an increase in left ventricular end-diastolic pressure (LVEDP) (P>0.05). Whereas in AF patients, BNP remained unchanged (before, 111.62+/-53.41pg/ml; at 20 minutes, 122.04+/-68.70g/ml; at 24 hours, 106.11+/-56.19pg/ml; respectively, P>0.05), while LVEDP increased (6.44+/-3.57mmHg vs. 8.56+/-3.17mmHg, P<0.01) without changes of LVEDV and SV (P>0.05). Conclusions These results indicate that high BNP level is associated with high mLAP and PAP in MS patients. Cardiac rhythm may play an important role in changes of BNP after PBMV. BNP could be a valid marker to reflect changes in mLAP and PAP after PBMV in SR patients, but not in patients with AF.