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Much depends on what the definition of minimally invasive is. The question is; Is minimally invasive a smaller incision or is it the length of a pump-run? Presently the off-pump advocates would suggest that less or no pump is better. Unfortunately many of the techniques for minimally invasive valve procedures require longer bypass times.

What we are trying to achieve in the ideal operation is:

1. A perfect operation - no leakage either from valve replacement or repair. Ideally any valve that can be repaired should be.
2. Reduced pain.
3. Short length of stay.
4. Minimal morbidity.
5. No need for re-operations.

Finally, Nifong just recently published a prospective FDA trial of 112 patients in ten centers undergoing robot-assisted mitral valve repairs. These presumably were experienced centers and were selected carefully for this trial. Unfortunately, the results are only fair. Eighty percent of the patients either had a ring alone or a ring with quadrangular resection. Obviously the majority were not complex operations. The cross-pump time was 2.1 hours and the bypass time was 2.8 hours. This would be considered excessive by almost any standard. Unfortunately 9, or nearly 10%, had what equaled to 2+ mitral regurgitation one month postoperatively. Three to six of these patients had re-operations and five to six needed mitral valve replacement. Remember that these are patients who had the easiest mitrals to fix. I should state that to get 112 patients in this trial, 324 other patients were analyzed and rejected because they had 'too complex disease'. Too complex disease was defined as essentially everything but posterior leaflet problems or annular dilatation.

The major problem of course is that valvular heart disease is not a common operation for the majority of surgeons. This is particularly true for mitral valve repair. Savage and colleagues did a STS database review and noticed that only 36% of over 20,000 mitral valve operations were repairs. It is presumed that some patients truly had mitral stenosis, but clearly the majority of these patients had mitral regurgitation and did not undergo repair. (Reference: Annals of Thoracic Surgery, 2003; 75:828-25). More importantly the majority of surgeons do less than half a dozen mitral valve repairs a year. If, even in experienced hands, data shows that there is a longer pump time and cross clamp time, then obviously the person who does just an occasional valve operation probably should use a standard approach.

Another issue is that of pain. I must confess that nearly half of my valve operations are done through a mini-sternotomy. The pain in these patients is usually higher than the standard sternotomy. There is no question that if one uses a thoracotomy this is always more painful than a sternotomy. The issue here that we arguing is not minimally invasive but rather size of the skin incision.

The final and most important issue is the potential for catastrophes. Patients who undergo minimally invasive operations are usually the least complex. Morbidity and mortality should be minimal no matter what the approach. Most who perform minimally invasive operations with alternate cannulation strategies have at least witnessed one catastrophic event such as aortic dissection or malperfusion. These are rarely reported in the literature. Standard operations minimize this risk.