Perfusion lung scanning before and after percutaneous transvenous mitral commissurotomy--early estimation of lung congestion relief

Persistence of lung function abnormalities despite sustained success of percutaneous mitral valvotomy: the need for an early indication

AIMS

We assessed early and long-term pulmonary function changes after percutaneous balloon mitral valvotomy (PBMV).

METHODS AND RESULTS

Mitral area, lung function, and exercise capacity were evaluated before, immediately after, and 3 months, 6 months, and 12 months after successful PBMV in 24 patients. PBMV resulted in a significant and sustained increase in mitral area, from 1.0 +/- 0.1 to 1.9 +/- 0.1 cm2 (p = 0.001) [mean +/- SD], with a progressive increase in exercise tolerance at 6-month follow-up (from 22.6 +/- 1.4 to 28.2 +/- 1.2 mL/kg, p = 0.0001). An immediate drop in the diffusing capacity of the lung for carbon monoxide (DLCO) was observed (from 26.7 +/- 1.5 to 22.3 +/- 1.1 mL/min/mm Hg, p = 0.0002) after PBMV, followed by a gradual regression to baseline values at 3 months; at 1 year, the DLCO remained elevated (27.3 +/- 6.3 mL/min/mm Hg). The flow in the small airways was reduced at baseline, and there was no significant change during follow-up.

CONCLUSIONS

PBMV produces an initial decrease in DLCO, suggesting a reduction of pulmonary congestion. During follow-up, the regression to the initial lung diffusion values despite a sustained hemodynamic improvement suggests that some irreversible interstitial changes were present. In patients with mitral stenosis, an impairment of lung function parameters suggests that PBMV must be performed early, even if patients have few symptoms.

Long-term clinical and echocardiographic outcome in patients with mitral stenosis treated with percutaneous transvenous mitral commissurotomy

Long-term follow-up after percutaneous transvenous mitral commissurotomy (PTMC) is limited. Ninety-four middle-aged (51+/-9 years) mitral stenosis patients who underwent successful PTMC were followed up with annual echocardiography for 6.1+/-1.4 years. PTMC success was defined as either mitral valve area (MVA) >1.5 cm2 or a MVA of more than twice the pre-procedural value, together with no worsening of mitral regurgitation >grade 2+. Mitral valve replacement (MVR), worsening of congestive heart failure (CHF), and thromboembolism were sought for survival analysis. Restenosis was defined as loss of more than 50% of the initial procedural MVA gain. Functional limit of daily activities was assessed through a questionnaire. The study population was divided into group 1 (post-procedural MVA >2.0 cm2), group 2 (MVA > 1.5 cm2 and < or = 2.0 cm2) and group 3 (MVA < or = 1.5 cm2). The 6-year survival with freedom from MVR, CHF, thromboembolism, and combined events (MVR+CHF) was 92%, 95%, 91%, and 88%, respectively. No group 1 patient experienced MVR or CHF. Restenosis was predominant in group 3. Deterioration of daily activities during follow-up was not observed in group 1; however, it was significant in group 2 (p<0.05) and group 3 (p<0.001). These results demonstrated that patients who attained a large MVA (>2.0cm2) immediately after PTMC maintained their procedural benefit with less clinical complication and with less limitation of daily activity.