Long-term (36-63 month) clinical and echocardiographic follow-up after Inoue balloon mitral commissurotomy

Patient profile and results of percutaneous transvenous mitral commissurotomy in mitral restenosis following prior percutaneous transvenous mitral commissurotomy vs surgical commissurotomy

BACKGROUND

Patients with mitral restenosis who have undergone prior PTMC or surgical commissurotomy have increased. Predictors of outcome of repeat PTMC in either subgroup of patients may be different.

AIMS AND OBJECTIVES

Aim was to assess and compare the immediate results of PTMC in patients who had undergone a prior PTMC or surgical commissurotomy.

METHODS AND RESULTS

This is a single center, prospective, open label study. Of 70 patients in study, 44 (62.85%) patients had prior history of PTMC and 26 (37.15%) had prior surgical commissurotomy (closed/open). Average time from the initial procedure was 8.88 ± 5.36 years overall, 6.75 ± 3.38 for patients with prior PTMC and 16.73 ± 3.67 for patients with prior surgical commissurotomy. Prior PTMC group had 75% female, patients with prior surgical commissurotomy were older (44 ± 7 vs 33.57 ± 9.1 years, p = 0.001), had higher NYHA class (III/IV in100% vs 86.36%, p = 0.006.), higher atrial fibrillation (73.1% vs 25% p < 0.0001) and higher Wilkins' score (>8 in 88.46% vs 68.18%, p = 0.05). Successful PTMC was lower (65.4% vs 84.1%) in patients with prior surgical commissurotomy, though statistically not significant (p = 0.07). After PTMC, mitral valve area, PA systolic pressure, LA mean pressure and trans-mitral gradient were similar. Post procedure complications were not different in both the groups.

CONCLUSION

PTMC for mitral restenosis in patients with prior surgical valvotomy is as effective as in patients with prior PTMC despite older age, higher NYHA class, higher Wilkins score and atrial fibrillation and can be considered in all patients with restenosis irrespective of the type of past procedures done.

Restenosis and adverse clinical events after successful percutaneous mitral valvuloplasty: immediate post-procedural mitral valve area as an important prognosticator

AIMS

We sought to investigate the factors associated with restenosis and its potential association with late clinical deterioration after successful percutaneous mitral valvuloplasty (PMV).

METHODS AND RESULTS

We analysed echocardiographic (median 74 months) and clinical (median 109 months) follow-up data of 329 patients who achieved procedural success, defined as mitral valve area (MVA) > or =1.5 cm(2) and mitral regurgitation (MR) < or =2/4, between 1995 and 2000. Clinical events included cardiovascular death, mitral valve surgery, and repeat PMV. The 1, 3, 5, 7, and 9 year rates of restenosis-free survival were 99 +/- 1%, 97 +/- 1%, 95 +/- 1%, 86 +/- 3%, and 72 +/- 4%, respectively. The 1, 3, 5, 7, and 9 year rates of event-free survival were 99.7 +/- 0.3%, 96.4 +/- 1.0%, 94.5 +/- 1.3%, 90.8 +/- 1.6%, and 90.0 +/- 1.7%, respectively. Immediate post-PMV MVA and commissural MR or splitting, indicators of procedural adequacy, were independent predictors of both restenosis and clinical events. The best immediate post-PMV MVA cut-off value for predicting both restenosis and clinical events within 5 years after successful PMV were 1.8 cm(2) [95% confidence interval (CI) = 1.7-1.9] and 1.9 cm(2) (95% CI = 1.7-2.0), respectively. Patients with immediate post-PMV MVA <1.8 cm(2) showed significantly lower event-free survival rate than those with post-PMV MVA > or =1.8 cm(2) (P < 0.001).

CONCLUSION

Immediate post-PMV MVA> or =1.8 cm(2) was an important predictor of both restenosis- and clinical event-free survival and this value should be considered as a component of optimal result.

Feasibility, safety, and morphologic predictors of outcome of repeat percutaneous balloon mitral commissurotomy

Early and mid-term results of repeat percutaneous balloon mitral commissurotomy (PBMC) were analyzed in 35 patients with symptomatic valvular restenosis: 12 patients (34%) after first successful PBMC and 23 patients (66%) after successful surgical closed mitral commissurotomy. Twenty-one patients had bilateral fused commissures, and 14 patients had unilateral or bilateral split commissures. Mitral valve area gain was significantly greater in the group with fused commissures compared with the group with split commissures (0.6 +/- 0.2 vs 0.3 +/- 0.2 cm(2), respectively, p = 0.04).

Randomized comparison between Inoue balloon and metallic commissurotome in the treatment of rheumatic mitral stenosis: immediate results and 6-month and 3-year follow-up

The metallic commissurotome (MC) technique is a cheaper alternative to the Inoue balloon (IB) technique for percutaneous mitral valvuloplasty (PMV). There are no randomized trials comparing these techniques with longer follow-up of the patients. The objective of this study was to compare the immediate results and short- and medium-term follow-up of PMV using either the IB or the MC technique. Fifty patients with rheumatic mitral stenosis were randomly assigned to PMV using the IB (n = 27) or the MC (n = 23) technique. There were no significant differences between the groups regarding baseline clinical, echocardiographic, and hemodynamic data. Clinical and echocardiographic follow-up were done 6 months and 3 years after the procedure. The success rate was 100% in the IB group and 91.3% in the MC group (P = 0.15); two patients in the latter group developed mitral regurgitation grade 3/4, requiring elective surgery. The mean final mitral valve area was bigger in the MC group (2.17 +/- 0.13 vs. 2.00 +/- 0.36 cm2; P = 0.04), but after 6-month and 3-year follow-up, this difference was no longer significant (2.06 +/- 0.27 vs. 1.98 +/- 0.38 cm2, P = 0.22, and 1.86 +/- 0.32 vs. 1.87 +/- 0.34 cm2, P = 0.89, respectively). This finding suggests valve stretching as an important mechanism of valve dilation with the MC. Three patients in the MC group and two patients in the IB group (P = 0.65) developed mitral valve restenosis; one of them underwent repeat PMV and the other four, all asymptomatic, were clinically followed. PMV performed either with the IB or the MC technique is effective and provides excellent short- and medium-term outcomes regardless of the technique employed.

Serial echocardiographic evaluation of restenosis after successful percutaneous mitral commissurotomy

OBJECTIVES

This study was designed to determine predictors of restenosis after successful percutaneous mitral commissurotomy (PMC) and its relationship to late clinical outcome.

BACKGROUND

The restenosis rate after PMC and its relationship to late clinical outcome is poorly defined.

METHODS

Serial echocardiography was performed in 310 patients who underwent PMC. Restenosis, defined as mitral valve area (MVA) <1.5 cm(2) and > or = 50% loss of initial MVA increase, was determined by both two-dimensional (2D) and Doppler echocardiography. Clinical, echocardiographic and cardiac catheterization variables were evaluated to determine predictors of restenosis. The relationship between restenosis and major adverse clinical events (death, repeat PMC or mitral valve replacement) and functional status was assessed.

RESULTS

Acute procedural success occurred in 206 patients (66%), who were then followed for restenosis. The cumulative restenosis rate was approximately 40% at six years after successful PMC (44% by 2D and 40% by Doppler MVA). The only independent predictor of restenosis was echocardiographic score (restenosis at five years was 20% for score <8 vs. 61% for score > or = 8, p < 0.001). The decline in MVA and occurrence of restenosis was gradual and progressive during the follow-up period. Procedural results and baseline factors predicted event-free survival. Restenosis by 2D MVA was related to adverse events or New York Heart Association functional class 3 to 4 symptoms, but restenosis was not an independent predictor of clinical outcome by multivariate analysis.

CONCLUSIONS

Restenosis is a common, gradual and progressive occurrence after successful PMC and is predicted by higher echocardiographic score. Restenosis is related to late adverse clinical outcome, though clinical outcome remains best predicted by the acute procedural results of PMC.

[Diagnosis and differential therapy of mitral stenosis]

Clinical symptoms and diagnostic findings in patients with mitral stenosis are usually determined by the extent of the stenosis. Compared to a normal mitral valve area (MVA) of > 4 cm2, MVA in patients with severe mitral stenosis is usually reduced to < 1.5 cm2. In older patients symptoms are frequently influenced by concomitant diseases (e.g. atrial fibrillation, arterial hypertension or lung disease). An important diagnostic element besides anamnesis, auscultation, ECG and chest X-ray is echocardiography, which is required in order to measure non-invasively and reliably the mitral valve gradient (MVG), the MVA and morphologic changes to the valves, as well as concomitant valvular disease, ventricular functions and, where appropriate, left-atrial thrombi. In addition to the surgical treatment of patients with severe mitral stenosis, which has been an established procedure for 50 years, percutaneous balloon mitral valvuloplasty (MVP) has recently established itself as an alternative option. At the current time, the Inoue technique seems to display the most advantages. Following transseptal puncture, the Inoue balloon is guided transvenously into the left atrium and then into the left ventricle using a special support wire. The balloon is short and soft. Its special unfolding character enables it to be placed securely in the mitral valve without any risk of ventricular perforation (Figure 1). As with surgical commissurotomy, balloon valvuloplasty leads to a separation of fused commissures. This results in a significant reduction of MVG, accompanied by an increase in the MVA (Figure 2). The results and success of MVP are influenced by the morphology of the valves and the changes to the subvalvular apparatus. In randomized studies, the results of surgical commissurotomy were comparable with those of balloon mitral valvulotomy. In our hospital, an increase in MVA from 1.0 to 1.8 cm2 could be achieved in 899 patients (mean age 56 +/- 3 years). In younger patients with less significantly changed valves, the results were correspondingly more favorable than in older patients (Figure 3). Provided valve morphology is suitable, a relapse following previous surgical commissurotomy is not a contraindication for MVP. The MVP complication rate is very low in skilled hands: mortality is below 1%; mitral insufficiency occurs in 3 to 10% of interventions; we observed a severe mitral insufficiency in 5% of our patient group. Thromboembolic complications may be prevented after exclusion of atrial thrombi by transesophageal echocardiography. The occurrence of a hemodynamically significant atrial septum defect is a very rare event. The mid-term results (5 to 10 years) and the low restenosis rate following MVP in patients with suitable valves are comparable with those of surgical commissurotomy. In older patients with considerably changed, calcified and fibrotic valves, restenosis may be expected within 1 to 5 years. In these patients MVP represents no more than a palliative intervention in order to prolong the point of surgery, for example in patients where a concomitant aortic valve disease in itself is not yet an indication for surgery. Special indications are to be found in young patients with severe mitral stenosis yet few symptoms, in pregnant females and in emergency situations, as well as in patients with Grade II mitral stenosis with intermittent atrial fibrillation. Catheter therapy is much less invasive than surgery. In case of failure the patient still has the option of surgical therapy. Patients with morphologically significantly altered valves usually receive a valve replacement since an unsuccessful reconstruction would lead to a second operation within a very short time interval. Contraindications for MVP are thrombi in the left atrium, a previously existing > Grade II mitral regurgitation and marked, degenerative destruction of the subvalvular apparatus or extensive calcification of the valves. MVP thus represents a significant addi