Summary

The use of mitral valvotomy is primarily limited to developing countries, where it increases survival without the need for reinterventions. The selection of the optimal type of valvotomy requires careful patient selection and evaluation of facility and operator factors must be evaluated.

  • mitral valvotomy
  • Wilkins Score
  • balloon mitral valvotomy
  • percutaneous mitral commissurotomy
  • mitral valve area
  • scoring systems
  • valvuloplasty
  • interventional techniques & devices

Mitral valvotomy is primarily used in the developing world because of the constraints in those countries, stated F. E. Smit, MD, University of the Free State, Bloemfontein, South Africa. Survival is increased, with an excellent or normal lifestyle, without the need for reintervention. A number of factors must be considered to select the type of valvotomy, including patient factors (eg, where the patient lives and the stage of the disease) as well as facility and operator factors (eg, level of training and available resources).

Several scoring systems have been developed to help optimize patient selection. The Wilkins score evaluates the extent of valvular disease and identifies patients who may be eligible for balloon valvotomy. Additional scores help predict long-term outcomes in patients with severe mitral stenosis, and a recent scoring system based on 20-year follow-up to obtain ideal results is guided by scoring systems such as the Wilkins score. Prognostic scoring systems for outcomes after balloon mitral valvotomy (BMV) include the transesophageal echocardiography (ECHO) assessment of commissure morphology [Sutaria N et al. Heart. 2006] and the scoring system by Zhang and colleagues that predicts late outcomes in patients with severe mitral stenosis [Zhang HP et al. Am Heart J. 1997]. A recent scoring system is based on the factors that predict late function as identified from the 20-year follow-up of patients who underwent percutaneous mitral commissurotomy (Table 1) [Bouleti C et al. Circulation. 2012].

Table 1.

Factors That Predict Late Outcomes After Percutaneous Mitral Commissurotomy

Closed mitral commissurotomy (CMC) and open mitral commissurotomy (OMC) provided similar survival at 30 years (49.1% vs 45.9%; P = NS), but the need for another procedure was lower with OMC (5 patients vs 44 with CMC; P < .05), as shown by Detter and colleagues [Detter C et al. Ann Thorac Surg. 1999]. A series by Chen and colleagues substantiated the hemodynamic improvements achieved with valvotomy [Chen CR, Cheng TO. Am Heart J. 1995].

Percutaneous mitral valvotomy using the double balloon technique provided similar results as CMC and the improvement in mitral valve area (MVA) was durable at the 15-year follow-up (mean follow-up 99 months) [Rifaie O et al. J Cardiol. 2009]. Mitral restenosis occurred in 5 patients in each group. The durable results with BMV were also shown by Farhat and colleagues in their 7-year follow-up [Farhat MB et al. Circulation. 1998].

OMC provided a durable improvement in MVA in a series of 100 patients with mitral stenosis [Antunes MJ et al. J Heart Valve Dis. 2000]. The mean MVA was 0.99 cm2 before surgery, increased to 2.89 cm2 after surgery, and was 2.37 cm2 on Doppler ECHO at the mean 8.5-year follow-up. An MVA > 2.0 cm2 was found in 81% of patients at follow-up. Importantly, this study showed that a postintervention MVA between 1.3 and 1.5 cm2 should not be considered a success, stated Prof Smit.

Valvuloplasty is ideal for complex disease, which includes all valves with pathology extending beyond the leaflet and valvular structural disease, as defined by the scoring systems. Such valves likely require either valvuloplasty or valve repair for the first attempt at valve salvage, stated Prof Smit.

The selection of a percutaneous or surgical procedure is determined by the available expertise, infrastructure, and cost. If both options are available, Prof Smit recommends BMV as the first choice, or CMC, if the patient is an ideal candidate according to the scoring systems. OMC should be performed for all other patients. An irreparable valve should be replaced because the possibility of another surgery may not be available in developing countries. A diagnostic program for early detection should be established.

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