Catheterization and Cardiovascular Diagnosis 37:200 (1996)

Editorial Comment

lnoue Balloon: Is It Really Easier? Carlos E. Ruiz, MD, PhD, FSCAI He Ping Zhang, MD Francis Y.K. LaU, MD, FSCAI Lorna Linda University School of Medicine Lorna Linda, California

Drs. Hung and Lau have covered the subject of the Inoue bal- loon commissurotomy in a superb fashion with excellent illustra- tions of how to perform this operation with the least number of complications and the highest number of successes [l]. We are sure those interventional cardiologists using the Inoue balloon will appreciate their pitfalls and tips on this “less demanding” tech- nique [ 1-31 to facilitate the procedure and to avoid the complica- tions which may occur in the optimum candidate.

We would heartily agree all patients should be thoroughly eval- uated clinically and specially by transthoracic and/or tranesoph- ageal echocardiography before considering a mitral valvotomy . If there is considerable subvalvular disease, we have learned from our 10-year follow-up experience, as well as other investigators, that for those patients, especially if they are in chronic atrial fi- brillation, surgical replacement of the mitral valve is probably a better option, and balloon valvotomy (regardless of single or dou- ble balloon technique) should probably be offered only under very special circumstances. Nevertheless any large volume operator will encounter these type of patients with a relative frequency and therefore the need for teaching the variations on the technique required to make the procedure safer and effective was very much needed, more so for the Inoue balloon than for the double balloon technique, since the latter is very standard and with minimal pos- sibilities for variations once the balloon sizes have been chosen.

Someone reading this well-detailed article who has a low case- experience with the Inoue balloon may have a hard time under- standing that a procedure which requires stepwise progressive di- latation with assessment of the results at each step where, in addition, operators have to ensure that the balloon has not popped back to the left atrium or into the left atrial appendage under fluoroscopy, would result in significantly less radiation exposure than the double balloon technique where, in the majority of cases, if the transseptal puncture was appropriately low, one single in- flation of the balloons suffices. However, we agree that short fluoroscopic time with this technique may be achieved by an op- erator who has performed over 1,000 cases [l], but not necessarily for the low volume operators. Another important but unmentioned fact is that an echocardiography machine is required inside the catheterization laboratory to assess the results in between each one

of the stepwise inflations. This can be very bothersome, especially in laboratories with limited space and more so if they are using a biplane unit, not to mention the cost involved in having an echocardiographer bound to the procedure, compounded by a longer procedure time from the additional time required to obtain echocardiographic information.

Both the single (Inoue) and double balloon catheter methods cause atrial septal defects and, to the best of our knowledge, the incidence of clinically significant left-to-right shunts is no differ- ent with either technique [3,4]. However, if the atrial septal wall is interrogated by color flow Doppler, it confirms the presence of left-to-right shunts universally in all patients. Closure of the de- fects depends on the residual mitral stenosis and/or regurgitation post dilatation.

Nevertheless we think that a very detailed manuscript on dif- ferent tips about the Inoue balloon mitral valvotomy was very much needed for this “less demanding” technique, in view of how their technique “continues to evolve,” and certainly the authors have one of the largest experiences with this technique and have covered in great detail almost every imaginable problem encoun- tered with the technique and how to resolve or prevent them. However, in view of the many factors that need to be considered using this balloon and the multiple precautions required depending on different mitral valve anatomy, the manufacturer should con- sider strongly recommending operators to be extensively trained in the use of this balloon catheter prior to becoming independent operators.

It is quite obvious this manuscript reiterates our position, that this procedure, whether using Inoue balloon or double balloon techniques, should not be done by low volume operators and far less by those “occasional” operators that may be misled by the “theoretical simplicity” of the procedure.

REFERENCES 1. Hung JS, Lau KW: Pitfalls and tips in Inoue balloon mitral com-

missurotomy. Cathet Cardiovasc Diagn 37:188-199, 1996. 2. Bassand JP, Schiele F, Bernard Y, Anguenot T, Payet M, Ba SA,

Daspet JP, Maurat JP: The double-balloon and Inoue techniques in percutaneous mitral-valvuloplasty: Comparative results in a series of 232 cases. J Am Coll Cardiol 18:982-989, 1991.

3. Sharma S, Loya YS, Desai DM, Pinto RJ: Percutaneous mitral valvotomy using Inoue and double balloon technique: Compari- son of clinical and hemodynamic short term results in 350 cases. Cathet Cardiovasc Diagn 29:18-23, 1993.

4. Ruiz CE, Zhang HP, Macaya C, Aleman EH, Allen JW, Lau FYK: Comparison of Inoue single-balloon versus double balloon technique for percutaneous mitral valvotomy. Am Heart J 123: 942-947, 1992.

0 1996 Wiley-Liss, Inc.