The effect of baseline pulmonary artery pressure on right ventricular functions after mitral balloon valvuloplasty for rheumatic mitral stenosis: a tissue Doppler imaging study

OBJECTIVES
We evaluated the effect of baseline pulmonary artery pressure (PAP) on right ventricular functions after percutaneous mitral balloon valvuloplasty (PMBV) for rheumatic mitral stenosis (MS).

STUDY DESIGN
The study included 56 patients (15 males, 41 females; mean age 35 years) who underwent PMBV for isolated rheumatic MS. The patients were divided into two groups according to the baseline median systolic pulmonary artery pressure (PAP ≥40 mmHg, n=33; PAP <40 mmHg, n=23) measured before PMBV by echocardiography. Right ventricular function was assessed by pulse wave Doppler tissue imaging and the Tei index. Assessments were repeated 48 hours and three months after PMBV.

RESULTS
The peak systolic (S) velocity of the lateral tricuspid annulus did not differ between the two groups at baseline. In patients with pulmonary artery hypertension (PAH), it showed a slight increase at 48 hours, but fell behind the baseline at three months. In patients without PAH, it showed a significant increase at 48 hours and remained unchanged at three months. Peak late diastolic (A) velocities were significantly higher at all times in patients without PAH. Patients with PAH had a significantly higher E/A ratio both at baseline and at 48 hours; however, at three months, this difference disappeared. Patients with PAH had higher isovolumic relaxation time (IVRT) at baseline and 48 hours; however, final IVRT was lower than the baseline only in patients with PAH. Isovolumic contraction time showed a steady but insignificant increase in both groups over three months. E-wave deceleration time showed a significant increase and contraction time showed a slight increase over three months only in patients with PAH. The baseline Tei index was higher in patients with PAH (p=0.004). Changes in the Tei index over time were not significant.

CONCLUSION
Our findings suggest that, If PMBV is performed before the development of PAH, it may be more effective in the improvement of right ventricular longitudinal functions in patients with rheumatic MS.