Believe It: Mitral Valve Repair Beats Replacement for Severe Regurgitation, Registry Shows

Almost 20 years’ worth of follow-up in an international registry shows that patients with degenerative mitral regurgitation who underwent mitral valve (MV) repair had better survival, fewer reoperations, and fewer valve-related complications than patients originally treated with MV replacement.

The study findings, albeit not from a randomized controlled trial, lend support to both American and European guidelines that give MV repair a Class I indication. While physicians and surgeons may not be surprised by the results, study co-author Jean-Louis Vanoverschelde, MD (Cliniques Universitaires Saint-Luc, Brussels, Belgium), told TCTMD they should serve as a useful reminder at a time when, despite evidence and despite recommendations, a “significant number” of patients with degenerative MV regurgitation are still sent for replacement, not repair.

“It may not be the majority any more but in the US it is close to 40%, so clearly the message has not gone through that it is better to repair than replace,” he said, noting that MV replacement remains relatively high in Europe as well. “It is something that is still very, very much prevalent, so that means that many surgeons don't believe that [repair is superior], maybe because the evidence is not sufficient. So this reminder is not useless.”

Vanoverschelde, first author Siham Lazam, MD (Cliniques Universitaires Saint-Luc), and colleagues reported their findings early online last week in Circulation.

Gold From MIDA

The Mitral Regurgitation International Database (MIDA) is a multicenter registry enrolling patients at six European and US centers. The current analysis included 1,992 patients with severe degenerative mitral regurgitation with flail leaflet who underwent MV repair (n = 1,709) or MV replacement (n = 213) between 1980 and 2005. Medically treated patients were excluded, as were patients with ischemic MR, significant aortic valve disease, congenital heart disease, mitral stenosis, or prior valve surgery.

Following propensity matching, Lazam et al report that operative mortality was significantly lower for repair than for replacement. Over a mean follow-up of 9.2 years (but ranging from 4.4 to 18.1 years), survival in the MV repair group was roughly double that seen in the replacement group, in both the overall and the propensity-matched analysis.

Survival: Mitral Valve Repair vs Replacement

Superiority of mitral valve repair was seen across all subgroups analyzed.

“These data support current recommendations and substantiate the contention that, when feasible, MV repair should be the preferred treatment of severe degenerative MR and should remain a central condition of treatment algorithms and quality measure of valve centers,” the authors conclude.

‘Not Shocking at All’

Vanoverschelde believes there are entrenched referral patterns that he hopes can change with these new data.

“Many times a cardiologist refers just to the surgeon he knows and this might not be the right approach,” he said. “Even if [the patient] needs to travel a lot of miles, it is better to get a MV repair than a MV replacement. So if you do not have a surgeon capable of repairing a valve in your institution, then hopefully this kind of paper will make cardiologists think about sending their patients to another institution for a MV repair rather than having an MV replacement, because 20 years down the road, the difference in survival between the two groups—it speaks for itself.”

Commenting on the study for TCTMD, Francesco Maisano, MD (University Hospital Zurich, Switzerland), called the findings “not shocking at all,” although he added the caveat that the study was not randomized, so its results are subject to potential bias.

“But this is a very large, retrospective study with propensity matching, which shows without any doubt, that repairing is better than replacing,” Maisano agreed. “There could be a risk of recurrence with repair, but on the other hand, the risk of events with having a foreign body in a complex environment like the mitral valve—this is not without risk and not without consequence,” he added, particularly given the need for long-term anticoagulation.

“So in degenerative MR, mitral repair is better than replacement, full stop,” he said. “There is nothing new here, but this is solid evidence.”

Any Takeaways for Percutaneous Mitral Interventions?

Another question is whether these results from the surgical field tell clinicians and researchers anything about repair versus replacement in the burgeoning field of percutaneous mitral valve interventions.

According Vanoverschelde, the answer is: “Not much.”

“In my point of view, the MitraClip is a nice procedure,” he said, “but it is tedious, it is difficult, you never get a perfect result. . . . And we don’t have enough follow-up to know whether a successful MitraClip repair will be a successful and safe alternative.”

By comparison, robotic surgical repair of degenerative MR that does not require a sternotomy in a young, otherwise healthy patient can yield excellent long-term results, Vanoverschelde reported. “So at this this stage, I don't think [percutaneous repair] offers any competition for surgical repair. In some years, when we have percutaneous valves which may well be much more efficient than we have now surgically, this will need to be reassessed.”

But at this stage, he said, you cannot extrapolate to say that percutaneous repair is also better than open surgical replacement, because it’s not “the same kind of repair.”

Maisano, however, was more positive about percutaneous procedures, pointing out that whereas 2015 was the year of big device company acquisitions in the mitral valve replacement space. Just this week Edwards Lifesciences acquired a mitral valve repair technology, signaling a resurgence in interest in repair.

When it comes to developing percutaneous approaches to mitral valve disease, “we should not reinvent the wheel,” Maisano said, adding that unlike PCI and CABG, which are very different approaches to the treatment of coronary artery disease, percutaneous valve procedures closely imitate the surgical approach. As such, it may be that percutaneous repair, rather than replacement, may be the best way forward at least for severe mitral regurgitation with flail leaflet.

Maisano also disputed the idea that percutaneous repair is, today, an imperfect substitute for surgical repair. “The combination of leaflet and annual repair is technically feasible,” he said. “Therefore transcatheter repair has the potential to fully reproduce the surgical standard with lower risk and less invasiveness.”