Percutaneous balloon mitral valvuloplasty: comparison of double and single (Inoue) balloon techniques

A new over-the-wire percutaneous mitral balloon valvuloplasty technique

OBJECTIVES

To develop and evaluate a new over-the-wire technique for mitral valvuloplasty that is both technically easier and less costly.

BACKGROUND

Rheumatic heart disease (RHD) and resultant mitral stenosis (MS) carries a significant burden of disease worldwide. The prevalence is however concentrated in lower income countries where the current gold standard for percutaneous mitral valvuloplasty (PMBV)-the Inoue technique, is not always available due to cost and technical complexity.

METHODS

The development of an over-the-wire technique involving a steerable catheter to aid crossing of the valve and a dedicated TAVI wire is described. The procedure evolved over the initial eight cases and the final standardized procedure was performed in 16 cases. Clinical, echocardiographic and procedural outcomes are described in 16 consecutive cases performed at a single center.

RESULTS

The procedure was performed with 88% procedural success and only one technical failure during the development phase. 2/24 patients had moderate mitral regurgitation (MR) afterwards but one had unfavorable anatomy and the other had pre-procedural moderate MR. The average procedural duration was 66 min, which was shortened significantly over time. No procedural deaths or conversion to open surgery at 1 year. Procedural cost was 44% lower than the Inoue technique.

CONCLUSION

We present favorable results of a new PMBV technique that is cheaper and technically easier in our opinion.

Learning curve of the Inoue technique of percutaneous mitral balloon valvuloplasty

There is controversy as to whether the double-balloon or the Inoue technique of percutaneous mitral balloon valvuloplasty (PMBV) provides superior immediate and long-term results. This study was undertaken to analyze the effect of the learning curve of the Inoue technique of PMBV in the immediate and long-term outcome of PMBV. The learning curve of Inoue PMBV was analyzed in 233 Inoue PMBVs divided into 2 groups: "early experience" (n = 100) and "late experience" (n = 133). The results of the overall Inoue technique were compared with those of 659 PMBVs performed with the double-balloon technique. Baseline clinical and morphologic characteristics between early and late experience Inoue groups were similar. Post-PMBV mitral valve area (1.89 +/- 0.56 vs 1.69 +/- 0.57 cm(2); p = 0.008) and success rate (60% vs 75.9%; p = 0.009) were significantly higher in the late experience Inoue group. Furthermore, there was a trend for less incidence of severe post-PMBV mitral regurgitation > or = 3+ in the late experience group (6.8% vs 12%; p = 0.16). Although the post-PMBV mitral valve area was larger with the double-balloon technique (1.94 +/- 0.72 vs 1.81 +/- 0.58 cm(2); p = 0.01), the success rate (71.3% vs 69.1%; p = NS), incidence of > or = 3+ mitral regurgitation (9% vs 9%), in-hospital complications, and long-term and event-free survival were similar with both techniques. In conclusion, there is a significant learning curve of the Inoue technique of PMBV. Both the Inoue and the double-balloon techniques are equally effective techniques of PMBV because they resulted in similar immediate success, in-hospital adverse events, and long-term and event-free survival.

Long-term clinical and echocardiographic outcome of percutaneous mitral valvuloplasty: randomized comparison of Inoue and double-balloon techniques

OBJECTIVES

The purpose of the present study was to compare the long-term clinical and echocardiographic results of the Inoue and the double-balloon techniques.

BACKGROUND

The large randomized trial comparing the extent of commissurotomy and the long-term results between the double-balloon and Inoue balloon techniques has not been reported.

METHODS

We conducted a prospective, randomized trial comparing two procedures in 302 consecutive patients who underwent percutaneous mitral valvuloplasty (PMV) using Inoue (n = 152; group I) or double-balloon technique (n = 150, group D) between 1989 and 1995. The sample size was planned to provide the study with approximately 80% power for the detection of a 10% difference between the two groups.

RESULTS

There were no significant differences in baseline characteristics between the two groups. Immediately after PMV, mitral valve area (MVA) increased from 0.9 +/- 0.2 to 1.8 +/- 0.3 cm2 in group I and from 0.9 +/- 0.2 to 1.9 +/- 0.3 cm2 in group D. No significant differences existed between the two groups in terms of development of commissural splitting, commissural mitral regurgitation (CMR), moderate to severe mitral regurgitation (MR) and MVA after PMV. The successful immediate results (MVA > or =1.5 cm2 and MR < or =2) were achieved in 127 (84%) patients of group I and 122 (81%) patients of group D (p = NS). Annual clinical and echocardiographic evaluation was completed for 290 (96%) patients with mean follow-up of 51 +/- 27 months. Adverse events occurred in 19 (13%) patients of group I (3 deaths, 7 mitral valve replacements, 5 repeat PMV, 2 NYHA class > or =3, 2 technical failures) and 16 (11%) patients of group D (2 deaths, 10 mitral valve replacements, 3 repeat PMV, 1 NYHA class > or =3). Estimated actuarial seven-year event-free survival was 75 +/- 7% in group I and 82 +/- 6% in group D (p = NS). Estimated actuarial seven-year restenosis-free survival was 67 +/- 7% in group I and 76 +/- 6% in group D (p = NS). On multivariate analysis, unsuccessful immediate result (p < 0.001) and absence of CMR (p < 0.01) were independently related with events. Absence of CMR and smaller mitral valve area after PMV were independently related with restenosis (p < 0.001).

CONCLUSIONS

The Inoue and double-balloon techniques were equally effective in commissurotomy and produced similar, excellent long-term results. The achievement of complete commissurotomy with development of CMR or larger post-PMV mitral valve area is important to optimize the long-term results of PMV.

Percutaneous balloon mitral valvuloplasty

Percutaneous balloon mitral valvuloplasty, first performed by Inoue in 1982, was a rational progression from 4 decades of experience with the blunt surgical dilatation technique of closed mitral commissurotomy. As with surgical commissurotomy, balloon valvuloplasty relieves mitral stenosis by the splitting of fused commissures. A series of studies have shown that balloon valvuloplasty achieves excellent acute hemodynamic results in close to 90% of patients, with a typical 100% increase in mitral valve area. Over the past 15 years since Inoue's first patient, a number of other techniques have been introduced and largely discarded in favor of the original approach. Advances have occurred along the lines of improved noninvasive assessment of mitral valve disease, which have allowed better case selection and prediction of outcome. Follow-up series have shown sustained improvement, with modest rates of complications and restenosis. Comparative studies have shown that balloon valvuloplasty is as effective and safe as surgical commissurotomy, and is a cost-effective procedure of first choice in ideal patients.

Inoue balloon deformity and rupture during percutaneous balloon valvuloplasty

In the management of mitral stenosis, similar long-term results can be obtained by using either an Inoue balloon catheter or a double-balloon technique for percutaneous balloon valvuloplasty. There have been few reports concerning any deformity of an Inoue balloon. From January 1988 to June 1995, 263 procedures of either mitral or tricuspid valvuloplasty have been performed in this center. The Inoue balloon catheter technique was used for 245 procedures. A deformity of the Inoue balloon catheter was noted in 4 (1.6%) and actual rupture of deformed balloon occurred in one (0.4%). All deformities were found at the distal portion of the Inoue balloon. Valvular insufficiency became more severe after valvuloplasty in two cases. Following rupture of the balloon, neither arterial embolization nor perforation of the cardiac chambers developed. In conclusion, a deformity of the Inoue balloon, although rare, can develop during percutaneous balloon valvuloplasty. The deformity may portend balloon rupture if additional maximal dilatations are undertaken.

Understanding balloon mitral valvuloplasty: the Inoue technique

Severe mitral stenosis has traditionally been treated with surgical splitting or replacement of the mitral valve. A less invasive option is available, in which the value is stretched by an inflated balloon inserted via the femoral vein (percutaneous balloon mitral valvuloplasty). The most widely used method of mitral valvuloplasty, the inoue technique, is described in detail. Pertinent aspects of patient management and nursing care are also described.

Comparison of late outcome between Inoue balloon and double-balloon techniques for percutaneous mitral valvotomy in a matched study

The follow-up results between Inoue balloon (n = 43, group 1) and double-balloon (n = 43, group 2) mitral valvotomies were compared in a patient-to-patient matched study. Matching was based on patients' age, mitral valve echo score, fluoroscopic calcification, mitral valve area before valvotomy, and follow-up period. The mean follow-up period was 13 +/- 9 months for both groups. At follow-up, 72% of patients were symptom free in each group; 2 (4.7%) patients in group 1 and 1 (2.3%) patient in group 2 underwent mitral valve replacement surgery. Of these 3 patients, 2 died after surgery, 1 from each group. The mitral valve area by Doppler was 1.8 +/- 0.3 cm2 in group 1 and 1.8 +/- 0.4 cm2 in group 2 (p = 0.7); the area by echo planimetry was 1.7 +/- 0.3 cm2 in group 1 and 1.8 +/- 0.3 cm2 in group 2 (p = 0.3) at follow-up. Restenosis occurred in 5 (12%) patients from each group. The cumulative restenosis-free rate was 96% at 1 years, 78% at 2 years, and 58% at 3 years in group 1 and 98%, 76%, and 51%, respectively, in group 2 (p = 0.8). Balloon selection did not appear to influence the clinical outcome at follow-up. We conclude that both the inoue balloon and the double-balloon valvotomies are effective therapies with comparable follow-up results for patients with mitral stenosis.

Retrograde nontransseptal balloon mitral valvuloplasty using a modified Inoue balloon catheter

Retrograde nontransseptal balloon mitral valvuloplasty, a method developed in our institution for the treatment of symptomatic mitral stenosis, avoids transseptal catheterization. Until recently, the self-positioning Inoue balloon catheter, unlike all other commercially available balloon catheters, had not been employed in this nontransseptal technique due to the short length of its catheter shaft. To employ a self-positioning balloon in retrograde nontransseptal balloon mitral valvuloplasty, we modified the Inoue device by extension of the catheter shaft. After retrograde nontransseptal left atrial catheterization using a steerable cardiac catheter, the modified Inoue balloon catheter was inserted through the femoral artery and advanced to the mitral valve retrogradely. Valvuloplasty was performed in 20 patients, with a successful result achieved in all. The modified Inoue balloon catheter was easy to use in retrograde nontransseptal balloon mitral valvuloplasty and showed excellent stability during inflation. Mean mitral valve area increased from 1.0 +/- 0.29 to 2.23 +/- 0.64 cm2 (P < 0.001) and mean transmitral gradient decreased from 11.4 +/- 6 to 4.3 +/- 2.1 mm Hg (P < 0.001). No major or minor complications were observed. Retrograde nontransseptal balloon mitral valvuloplasty using a modified Inoue balloon catheter is a feasible and effective technique for the treatment of symptomatic mitral stenosis. It appears to combine the advantages of avoiding transseptal catheterization with the advantages of this balloon's special configuration.