The selection of patients for PTMC procedure is a complex decision involving the consideration of multiple variables, including the clinical profile, valve morphology, and the operator's skill.

I.  Patients with favorable mitral valve morphology

       PTMC procedure is best applied to symptomatic patients with moderate-to-severe mitral stenosis (mitral valve area <1.5 cm2) and favorable mitral valve morphology (pliable, non-calcified valve without significant subvalvular disease). In this subset of patients, PTMC predictably yields excellent results and a low risk of resultant severe mitral regurgitation. In asymptomatic patients with favorable valve anatomy, PTMC can be performed prior to non-cardiac surgery or planned pregnancy.

       Patients with moderate (angiographic grade 2+) mitral regurgitation but with otherwise favorable valve characteristics should be given a trial of Inoue-balloon PTMC where controlled stepwise dilation is possible, and the risk of severe mitral regurgitation in experienced hands is minimal. Should this procedure fail to provide sustained improvement, surgery in the form of valve replacement remains a viable option without exposing the patient to any additional risk.

       Inoue PTMC is technically less demanding and clearly more simple to perform than the double-balloon approach, thereby engendering a shorter procedural and irradiation time [1]. This advantage is vital in pregnant patients where the hazards of irradiation to the fetus are of paramount importance, and for patients with pulmonary edema in whom swift and expeditious PTMC is clearly desirable [2]. However, to minimize the hazards of fetal irradiation, it should be performed after the mid-second trimester, with adequate total abdominal and pelvic shielding, minimal use of fluoroscopy (by omitting diagnostic right heart catheterization and left ventriculography), and only by interventional cardiologists skilled in the transseptal and valvuloplasty techniques.


II.  Patients with adverse mitral valve morphology

       The utility of PTMC in patients with adverse valve morphology (calcified mitral valves and/or severe subvalvular disease) is unclear and controversial [1]. Most operators contend that these types of patients are better served with surgery, which often means mitral valve replacement, because PTMC in this setting is associated with an increased risk of complications and inferior long-term results [3-6]. In patients who pose a prohibitively high risk for valve surgery, PTMC may be a better option than surgery, and may occasionally be the only therapeutic modality available for some of these patients.

       On the other hand, some experienced operators [7,8] advocate more liberal use of the procedure because of a low risk of major complications (in particular, resultant severe mitral regurgitation), and the procedure continues to offer sustained functional benefits in a substantial number of patients. Notwithstanding, it cannot be overemphasized that PTMC in these patients can be technically demanding, and does require a higher level of technical skill and extra caution in executing the procedure [9].

       PTMC is also preferred over surgical mitral commissurotomy for patients who pose a prohibitively high risk for valve surgery either as a "definitive" treatment or as a temporary measure (bridge-to-surgery). In fact, PTMC may occasionally be the only therapeutic modality available for some of these patients, and obviously for those who refuse surgery. It is an attractive option in patients with restenosis after previous surgical commissurotomy where PTMC has been demonstrated to produce identical results as in patients with de novo mitral stenosis, without the increased morbidity and mortality (2-10%) associated with repeat surgery [10-13].


Table:  Recommended Treatment Strategies for Mitral Stenosis 		 
    * Coming Soon
 
 
 
 
 
 
 
 
 
 
 
 
  Patient Subset                                                                Recommended Treatment
  I. Pliable, non-calcified mitral valve with
   none or mild subvalvular disease, and with:

   a) absent or mild mitral regurgitation

   b) moderate mitral regurgitation

   c) with left atrial cavity thrombus


II. Non-pliable, grossly calcified mitral valve with
    significant subvalvular disease, and with:

    a) with or without moderate mitral regurgitation

    b) special clinical settings:
        - high-surgical risk
        - urgent non-cardiac surgery required
        - bridge procedure to mitral valve surgery
        - patient refusal for surgery
        - shortened lifespan from comorbidities 		 



PTMC

Trial of PTMC

OCS*





MVR

PTMC
 
 
 
 
 
 
 
 
 
 
MVR = mitral valve replacement; OSC = open surgical commissurotomy;
PTMC = percutaneous transvenous mitral commissurotomy;
*with thrombectomy


References:
  1. Lau KW, Hung JS, Ding ZP, et al. Controversies in balloon mitral valvuloplasty: The when (timing for intervention), what (choice of valve), and how (selection of technique). Cathet Cardiovasc Diagn 1995;35:91-100.

  2. Wu JJ, Chern MS, Yeh KH, et al. Urgent/emergent percutaneous transvenous mitral commissurotomy. Cathet Cardiovasc Diagn 1994;31:18-22.

  3. Hung JS, Chern MS, Wu JJ, et al. Short- and long-term results of catheter balloon percutaneous transvenous mitral commissurotomy. Am J Cardiol 1991;67:854-862.

  4. Dean LS, Mickel M, Bonan R, et al. Four-year follow-up of patients undergoing percutaneous balloon mitral commissurotomy. J Am Coll Cardiol 1996;28:1452-1457.

  5. Yoshida Y, Kubo S, Tamaki S, et al. Percutaneous transvenous mitral commissurotomy for mitral stenosis patients with markedly severe mitral valve deformity: Immediate results and long-term clinical outcome. Am J Cardiol 1995;76:406-408.

  6. Hung JS, Lau KW, Lo PH, et al. Complications of Inoue-balloon mitral commissurotomy - Impact of operator experience and evolving technique. Am Heart J 1999;138:114-121.

  7. Hung JS, Lau KW. Percutaneous transvenous mitral commissurotomy is an acceptable therapeutic alternative in patients with calcified mitral valve. J Invas Cardiol 1999;11:362-363.

  8. Wahl A, Meier B. Percutaneous mitral balloon valvuloplasty in non-ideal patients: Go for it without expecting too much. J Invas Cardiol 1999;11:359-361.

  9. Hung JS, Lau KW. Pitfalls and tips in Inoue-balloon mitral commissurotomy. Cathet Cardiovasc Diagn 1996;37:188-199.

  10. Medina A, De Lezo JS, Hernandez E, et al. Balloon valvuloplasty for mitral restenosis after previous surgery: A comparative study. Am Heart J 1990;120:568-571.

  11. Davidson CJ, Bashore TM, Michel M, Davis K for the NHLBI Balloon Valvuloplasty Registry participants. Balloon mitral commissurotomy after previous surgical commissurotomy. Circulation 1992;86:91-99.

  12. Jang IK, Block PC, Newell JB. Percutaneous mitral balloon valvotomy for recurrent mitral stenosis after surgical commissurotomy. Am J Cardiol 1995;75:601-605.

  13. Lau KW, Ding ZP, Gao W, et al. Percutaneous balloon mitral valvuloplasty in patients with mitral restenosis after previous surgical commissurotomy: A matched comparative study. Eur Heart J 1996;17:1367-1372.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
© 2002-2003 Dr. Jui-Sung Hung. All Rights Reserved.
Questions or Comments? Email shung@pipeline.com.