Immediate and Late Outcomes after Percutaneous Mitral Co,mmissurotomy

BACKGROUND: Percutaneous mitral commissurotomy(PMC) has been known as an effective therapeutic modality for moderate to severe mitral stenosis. However, long-term results and factors influencing late outcome after PMC remain to be elucidated. MATERIALS AND METHODS: Three hundred and forty-six patients received PMC at Seoul National University Hospital between August, 1988 and March, 1996. We evaluated long-term results of these patients and assessed demographic, clinical, echocardiographic and hemodynamic variables in order to identify predictors of immediate and late outcomes. RESULTS: PMC was completed without major complication or technical failure in 339(98%) out of 346 cases. A good immediate result was obtained in 67% of cases. Multivariate study identified echocardiographic score(P=0.004) and left atrial volume(P=0.009) as independent predictors of immediate outcome. The estimated 3-year and 5-year event-free survival rates were 95.8+/-2.5% and 90.6+/-4.3%, respectively. According to multivariate analysis, the independent predictors of late outcome were pre-PMC left atrial volume(P=0.03), post-PMC mitral valve area(P=0.01), and severity of mitral regurgitation after PMC(P=0.03). CONCLUSION: Percutaneous mitral commissurotomy as a treatment for patients with mitral stenosis is safe, and achives good long-term results. Pre-procedural echocardiographic score, left atrial volume, post-procedural mitral valve area, and severity of mitral regurgitation affect the immediate and late outcomes after PMC.

Changes of Plasma Endothelin-1 Concentration after Percutaneous Mitral Commissurotomy

BACKGROUND: Endothelin, a very potent vasoconstricting substance released from the endothelium, has been known to be elevated in various cardiovascular disorders, however, the sites of endothelin porduction as well as the influence of acute hemodynamic changes upon plasma endothelin-1 concentration remains elucidated. METHODS: In order to evaluate the probable site of endothelin production and relationship between levels of plasma endothelin and hemodynamic variables, six patients with moderate to severe mitral stenosis underwent percutaneous mitral commissurotomy(PMC) were included. Measurement of mean pulmonary arterial pressure, cardiac output as well as plasma endothelin-1 concentration of renal vein, main pulmonary artery, and ascending aorta were performed before and 20 minutes after PMC. RESULTS: After PMC, cardiac output increased significantly, whereas mean pulmonary artery pressure and transvalvular pressure gradient were reduced significantly(both p<0.05). Before PMC, plasma endothelin-1 concentration tended to be higher in renal vein(6.12+/-3.7pg/ml) and pulmonary artery(5.07+/-1.7) than that in aorta(3.05+/-1.2pg/ml). After hemodynamic improvement with PMC, plasma endothelin-1 concentration decreased at all the site, however the change at pulmonary artery was statistically significant. CONCLUSION: These results suggest that endothelin-1 may be produced mainly somewhere in systemic venous circulation such as kidney rather than pulmonary circulation, and plasma endothelin-1 concentration tends to decrease in response to the acute hemodydnamic im provement.

Transesophageal Echocardiographic Evaluation of Pulmonary Venous Flow Patterns before and after Percutaneous Mitral Commissurotomy

BACKGROUND: Pulmonary venous flow(PVF) is closely related to left atrial pressure(LAP) and percutaneous mitral commissurotomy(PMC) reduces LAP rapidly. However, PVF pattern in mitral stenosis(MS) with sinus rhythm after PMC remains to be elucidated. METHODS: Transesophageal echocardiographic pulsed Doppler examination was performed within 24 hours before and after PMC to evaluate PVF pattern in 10 patients of MS with sinus rhythm. RESULTS: Before PMC, both peak velocity(PV) and velocity time integral(VTI) during systole had significant negative correlations with mean LAP(r=-0.70, r=-0.79, respectively). After PMC, both systolic PV and VTI increased significantly without significant changes in diastolic PV and VTI. However, there was no significant correlation between systolic PV and mean LAP, and between systolic VTI and mean LAP after PMC. CONCLUSION: In mitral stenosis with sinus rhythm, these data suggest that systolic PVF decreases with increase of mean LAP and PMC could reverse this change without affecting diastolic PVF. However, acute hemodynamic changes of left atrium induced by PMC may contribute to the absence of correlation between mean LAP and systolic PVF after PMC.