The prognostic value of cardiac magnetic resonance in assessment of right ventricular function after percutaneous balloon mitral valvuloplasty

Abstract

Abstract Background Mitral stenosis (MS) results in right ventricular (RV) dysfunction secondary to chronic pulmonary hypertension. Poor outcomes have been reported in patients with persistent chronic RV dysfunction. Persistence RV dysfunction can affect the clinical improvement after percutaneous balloon mitral valvuloplasty (PBMV). Cardiac Magnetic Resonance (CMR) is emerged as a highly sensitive technique for assessment of RV function (RVF). Purpose To investigate RV function 3 months after PBMV using a variety of robust parameters associated with prognosis. Methods A prospective observational study was conducted in a tertiary University hospital included 31 patients with symptomatic uncomplicated MS with favorable morphology and having sinus rhythm who underwent PBMV. All patients were subjected to TTE and CMR examination 24 hours directly before and 3 months after PBMV for assessment of RV size and function. Results CMR showed reduced RV myocardial mass (36.1±6.1 vs 28.0±5.4g, P<0.001), RV end-diastolic volume (RV EDV) (123.5±31.3 vs 109.5±22.7 ml, P=0.03) and TR regurgitant fraction (19.6±8.6 vs 14.7±4.9%, P<0.001) On the other hand, there were increase in each of RV ejection fraction (60.0±10.4 vs 63.13±7.8%, P<0.001), RV stroke volume (SV) (50.2±15.1 vs 33.2±12.2 ml, P<0.001) and RV stroke index (44.2±7.7 vs 50.3±8.6 ml/beat/m2 <0.001). TTE showed improved systolic RV function parameters measured by fractional area change (42.1±7.8 vs 51.7±5.4%, P<0.00), Tei Index (0.6±0.1 vs 0.5±0.1, P<0.001) and TAPSE (22.2±3.3 vs 25.7±5.1 mm, P=0.04). Among RV diastolic parameters, there were an increase in TV-TDI E' (12.0±3.0 vs 14.0±2.0 cm/s, P<0.001), TV-TDI A' (13.0±3.0 vs 11.0±2.0 cm/s, P<0.001) and TV-TDI E'/A' (1.0±0.5 vs 1.3±0.3, P<0.001) with significantly decreased RV wall thickness (5.7±0.7 vs 4.3±0.8 mm P<0.001) 3 months after PBMV. Among patients who showing improved RV parameters by TTE, ten patients (32,3%) showed non improved RV end systolic volume, EDV, SV and stroke index by CMR. Conclusion Follow-up of RV function by TTE after PBMV yielded nearly similar results compared to CMR. However, CMR identified a subgroup of patient with persistent RV dysfunction 3 months after PBMV. That contributes to define the role of cardiac MRI in the evaluation of the prognosis in patients with MS. Funding Acknowledgement Type of funding sources: Public Institution(s). Main funding source(s): Assiut University hospital and Al Orman Institute