Assessment of the relationship between functional capacity and right ventricular ultrasound tissue characterization by integrated backscatter in patients with isolated mitral stenosis

Aim: The aim of the present study was to investigate right ventricular (RV) myocardial textural properties in asymptomatic and symptomatic mitral stenosis (MS) patients with normal RV systolic function using integrated backscatter (IBS). Methods: The study included 40 patients with MS of moderate or severe degree. Patients were classified into 2 groups according to NYHA class (asymptomatic group, NYHA class I, symptomatic group, NYHA class II-III). RV pulsed-wave tissue Doppler imaging (TDI) and IBS analyses were performed in all patients. Isovolumic contraction time (IVCT), systolic wave velocity (S), isovolumic relaxation time (IVRT), early diastolic wave velocity (E), and late diastolic wave velocity (A) were measured by TDI. IBS amplitude (IB) and cyclic variation (CV) of the RV lateral wall in the parasternal long-axis view were measured by IBS. CV was calculated by subtracting systolic IB from diastolic IB. Results: IVRT (54.2 ± 11.9 ms versus 86.2 ± 16.2 ms, P < 0.001) and A wave amplitude (10.2 ± 2.1 cm/s versus 13.6 ± 1.8 cm/s, P < 0.05) were higher whereas E wave amplitude (11.7 ± 1.6 cm/s and 10.3 ± 1.5 cm/s, P < 0.05) and E/A ratio (1.3 ± 0.3 versus 0.7 ± 0.1, P < 0.001) were lower in group 2. Symptomatic patients had a lower CV value of RV (9.5 ± 3.4 dB versus 6.7 ± 1.9 dB, P = 0.004). There was a positive correlation between CV and E/A (r = 0.964, P < 0.001) Conclusion: Symptomatic isolated MS patients had RV echo texture changes and diastolic dysfunction in comparison to asymptomatic ones with similar mitral valve areas in the presence of normal RV systolic function. In isolated MS, both pulsed-wave TDI and IBS may aid in the detection of RV diastolic pathology