Percutaneous mitral commissurotomy versus open mitral commissurotomy: a comparative study.

OBJECTIVE

Although many studies in medical literature are comparing percutaneous trans-septal mitral commissurotomy (PTMC) and open mitral commissurotomy (OMC), very few long-term comparative follow-ups are available.

METHODS

Between January 1991 and December 1997, 193 patients with isolated mitral stenosis were assigned either to PTMC (111 cases) or to OMC (82 cases). PTMC was performed in all cases with Inoue Ballon, OMC was performed with standard techniques. Categorical values were compared by chi square analysis, whereas continuous data were compared by Mann-Whitney test. Univariate survival and event free analysis (Kaplan-Meier+/-SE and log rank) were performed. Recurrent stenosis was classified any mitral valve area (MVA) less than 1.2 cm2 and whenever post-op. echo showed a loss more than 50% of the initial gain. Data were reported as mean+/-SD. Data concerning late echocardiographic assessment were studied with linear and logistic regression analysis.

RESULTS

The two groups were homogenous as far preoperative variables as sex, mean age, MVA, echo score and incidence of left atrial thrombosis were concerned. Mean NYHA was preoperatively higher in OMC (2.79+/-0.58) versus PTMC (2.42+/-0.5) (P = 0.001). There was no hospital mortality in both groups. Incidence of hospital complications was similar (4/ 111 after PTMC and 1/82 after OMC; P = 0.3). Seven year survival: 95.41+/-0.02 (PTMC) and 98.05+/-0.01 (OMC) (P = 0.3) and freedom from late complications did not show statistical differences: Embolism 98.78+/-0.01 in PTMC and 98.78+0.01 in OMC (P = 0.8); Recurrent stenosis 71.89+/-0.13 in PTMC versus 82.89+/-0.08 in OMC (P = 0.2); Reoperation 88.43+/-0.08 in PTMC versus 96.25+/-0.02 in OMC (P = 0.4). A larger MVA was found in patients undergone to OMC (2.05+/-0.35) versus PTMC (1.81+/-0.33) (P = 0.001). Furthermore mean NYHA was lower in OMC (1.14+/-0.3) versus PTMC (1.39+/-0.7) (P = 0.001).

CONCLUSIONS

Both techniques achieve with a low operative risk and low incidence of complications a good palliation of rheumatic mitral stenosis. Incidence of complications in the follow-up is similar. OMC allows a larger mitral valve area, a better functional recovery and a lower incidence of late mitral regurgitation.