Top News in Structural Heart Disease: 2018

The success of mitral valve interventions dominated the structural heart space in 2018 with two large trials showing disparate results.

“You had MITRA-FR, which was neutral—there was no benefit of clipping. Then you had COAPT, which was markedly positive,” said Anthony N. DeMaria, MD (University of California, San Diego). “Taken together, these two trials were the biggest news of the year in structural heart disease.”

Presented at the 2018 European Society of Cardiology Congress in August, MITRA-FR showed no benefit for MitraClip (Abbott) in terms of hard clinical outcome, deaths, or rehospitalization. Just a few weeks later at TCT 2018, COAPT showed that that heart failure (HF) rehospitalization and mortality at 2 years were significantly reduced with the MitraClip in patients with heart failure and severe functional mitral regurgitation (MR).

Hemal Gada, MD (UPMC Pinnacle, Harrisburg, PA), said the COAPT results provided “a youthful enthusiasm that’s been missing with regard to the mitral space for some period of time.”

DeMaria added that they were “a bit unexpected” since surgical mitral valve replacement and repair had never really been shown to accomplish these kinds of improvements for this population.

“We were looking for a win, especially knowing that surgical mitral valve therapy now has a class IIb indication even in the most optimized patient and that you’re really dealing with the unknown as to whether someone would have clinical benefit,” Gada noted. ”What COAPT did was assure that if you really select out the right patients and you do a great job with your medical management and they are still symptomatic with residual functional MR, [then] correcting the MR with this particular device can lead to really great clinical outcomes.”

Gada added that given the high likelihood that MitraClip will receive a commercial indication for functional MR by this time next year, the other important takeaway from COAPT is that current trials in this space will need to be altered. “Right now, MitraClip is not being included in many functional MR trials testing transcatheter therapies, and I think that's going to need to be revised to create a more appropriate randomization process,” he said.

Minimalist TAVR, Cardiomyopathy, and Endocarditis

Another exciting trial that Gada pointed to from 2018 was SOLVE-TAVI, also presented at TCT 2018, which found that in patients at high risk for surgery, there was no difference in the combined primary endpoint of all-cause mortality, stroke, moderate/severe valve regurgitation, and permanent pacemaker implantation at 30 days with self-expanding versus balloon-expandable devices. Additionally, there were no differences in outcomes between patients who had local versus general anesthesia.

Gada said the trial results drive home the idea that a minimalist TAVR strategy is essentially valve agnostic. “It’s a unique glimpse into a comparison between the two valve platforms, because that has not happened at least in this type of direct manner,” he said. “To be able to strategize patient management in a way that does not involve general anesthesia and to have that be noninferior to, if not better than, general was a really great insight.”

In the cardiomyopathy space, DeMaria noted that the ATTR-ACT study stood out. Presented at ESC 2018, it found that tafamidis (Vyndaqel; Pfizer) offered an advantage in terms of all-cause mortality and cardiovascular hospitalizations compared with placebo in patients with the transthyretin form of amyloid cardiomyopathy.

“That's big news, and it's comparable to COAPT in that you've got a disease entity for which no treatment has proven to be effective and all of a sudden along comes a therapy that is effective,” he observed.

Finally, DeMaria pointed to the POET study, published in September in the New England Journal of Medicine, which showed that patients with infective endocarditis could be safely switched to oral therapy once they have been stabilized on an intravenous course of therapy. According to the POET researchers, up to 50% of all patients may be candidates for a partial oral therapy regimen.

“It’s much more convenient and I think it could change treatment for infective endocarditis quite a bit,” DeMaria said.

Click here for more from TCTMD’s 2018 Year in Review.