Prognostic significance of changes in the compliance of the pulmonary venous system after isosorbiddinitrate in patients with mitral stenosis.

It is agreed that a stiff pulmonary venous bed can cause severe pulmonary hypertension. This condition can also influence the clinical and hemodynamic outcome of mitral valve replacement (MVR). This study has been aimed at assessing whether changes in the pulmonary venous compliance (PVcomp) after application of isosorbiddinitrate (ISDN) can be of prognostic value in patients 6 months after MVR. PVcomp was calculated according to the Hirakawa equation in 34 patients with isolated mitral stenosis (MS) before and after ISDN. In 19 patients (group I) there was an increase of PVcomp by more than 15% (5.3 vs. 8.1 ml/mmHg), while 15 patients (group II) showed no differences in PVcomp after ISDN, despite the significant decrease in PAP and PWP in both groups (measured with the use of Swan-Ganz thermodilution catheters). Six months after MVR a significant decrease in PAP, PWP, PVR and an increase in SVI was observed in both groups during rest. During effort (25 W), significant increases in PAP and PWP were recorded in most of patients from the group II, as opposed to group I. It is concluded that significant increase in PVcomp after ISDN in patients with MS can be a prognostic of good clinical results 6 months after MVR.