Correlation between Peri-Procedural B-Type Natriuretic Peptide Plasma Levels and Success of Percutaneous Balloon Mitral Valvuloplasty

Abstract

Rheumatic mitral stenosis, a valvular heart disease that develops as alate complication of rheumatic fever, is still an important issue in our country. Percutaneous mitral balloon valvuloplasty (PMBV) appeared to be the best therapeutic interventional option for patients with symptomatic and uncomplicated rheumatic MSwith favorable valve morphology. Successful procedure provides an immediate and long-term remarkable hemodynamic and symptomatic improvement. Consequences of successful percutaneous mitral balloon valvuloplasty was investigated in various studies and found to include improvement of impaired LV systolic function,reduction of left atrial size,regression of significant tricuspid regurgitation,andregression of severe pulmonary hypertension. Nevertheless, balloon valvuloplasty can have serious complications. Most of the adverse complications occur during the procedure. (i.e. during the process of interatrial septum puncture, manipulation of the balloon catheter in the left atrium, and commissurotomy of the mitral valve by the balloon catheter). Early markers of outcome other than symptoms and LV dysfunction are needed because the clinical or echocardiographic findings are often observed after something serious has happened. Consequently, they are associated with poor outcome.

B-type Natriuretic Peptide, a cardiac neurohormone secreted by ventricles in response to the excessive stretching of the ventricular myocytes and also from some atrial granules, was found to haveboth a diagnostic and prognostic role in LV dysfunction of different etiologies as well as in pathologic conditions that cause RV overload as in MV diseases. In the setting of MS, an increase in plasma BNP levels has been correlated with parameters of disease severity such as MV area, left atrial pressure, and pulmonary hypertension. Plasma BNP levels are expected to be reduced after successful PMBV, which was associated with the reduction of the LA pressure. Similarly, volume overload and LA enlargement and LV remodeling caused by mitral regurgitation induces BNP activation,which has been found to reflect severe consequences of mitral regurgitation and be a marker of poor outcome regardless its degree. Few studies have been conducted on BNP quantification in the field of PMBV.Collectively, they are not sufficient to build up evidence in that issue, especially due to the variety of contradictory results they brought up. Hence, it is suggested that BNP measurement may be of benefit in the population of patients undergoing PMBV in the area of determining the outcome which is the point in our study.Thus, our studytargeted the effect of successful and unsuccessful PMBV on plasma levels of BNP and investigating the relationship between the changes in hemodynamic variables and BNP levels changes after PMBV. The study included thirty patients withsevere symptomatic mitral stenosis. They werereferred to cardiac catheterization laboratory and underwent percutaneous mitral balloon valvuloplasty, within the period betweenMay 2016 and December 2016. All patients were subjected to thorough historytaking, full clinical assessment, 12-lead ECG, transthoracic and transesophageal echocardiographic assessment before the procedure. Echocardiographic reassessment was performed for all patients after the procedure. Blood sampling for BNP quantification was taken just before, 20 minutes and 12 hours after the procedure. Baseline BNP values were elevated in the whole study population compared with the normal values in adult healthy subjects. They had a significant positive correlation with age, MVA, PASP and LVEDP and a negative one with each of BMI and TAPSE. Twenty min postprocedural BNP had a significant positive correlation with age and LVEDP, while 12 h postprocedural BNP had a significant positive correlation with age only. Mean BNP values obtained 20 min and 12 h after the procedure were compared to mean baseline BNP, and showed no statistically significant variation, neither in successful nor unsuccessful PMBV groups. Changes in BNP 20 min after PMBV had a significant positive correlation with MVA, mLAP, and LVEDP; and a significant negative correlation with LAFI and TAPSE.