Study: PBMV holds up over long term follow-up
More than three-fourths of patients who received percutaneous balloon mitral valvuloplasty (PBMV) at a center in Brazil maintained procedural benefit over a median follow-up of 8.3 years, researchers reported in JACC: Cardiovascular Interventions.
The incidence of rheumatic mitral stenosis (MS) is declining but remains a significant cause of mortality and morbidity in developing countries, the authors noted. This study spanned from 1987 through 2010, with PBMVs peaking in the 1990s and declining more rapidly after 2002.
“After more than 30 years since its introduction, PBMV represents a reasonable therapeutic option for the treatment of most patients with rheumatic MS,” wrote lead author Rafael A. Meneguz-Moreno, MD, and colleagues. “Two decades after successful percutaneous mitral valvuloplasty, more than 75 percent of followed patients still exhibited sustained results. Prediction of late favorable results is multifactorial and strongly determined by age, post-procedure MVA (mitral valve area), and previous symptoms.”
The researchers enrolled 1,582 consecutive patients undergoing PBMV for severe rheumatic MS at their center. Procedural success was achieved in 90.9 percent of cases, defined as post-procedural valve area of at least 1.5 square centimeters and mitral regurgitation of moderate or lower without any major adverse cardiac and cerebrovascular events.
About 21 percent of these cases didn’t achieve long-term follow-up (median 8.3 years), but among those who did only 19.1 percent met the primary endpoint of all-cause mortality, need for mitral surgery or repeat PBMV. Independent predictors of that endpoint included New York Heart Association (NYHA) functional class III or IV (62 percent increased odds) and a post-procedural mitral valve area of less than 1.75 sq. cm (67 percent increased odds).
Long-term follow-up was particularly important in this population, the authors noted, as the average age at baseline procedure was 34. Eighty-six percent of the patients were women, consistent with previous studies of PBMV.
“As main findings, we can highlight the high rate of acute procedure success and the long-term clinical and echocardiographic maintenance of the results,” Meneguz-Moreno et al. wrote. “Additionally, the most important predictors of long-term outcomes after a successful procedure are suboptimal valve opening after procedure, age and previous worse NYHA functional class.”
In an accompanying editorial, Zoltan G. Turi, MD, pointed out several limitations with the study and questioned the use of the term “very long term” to define a median follow-up of 8.3 years. He said the impact of the paper is hindered by the young, relatively healthy study population along with the open-label assessments, lack of core labs to evaluate results and the single-site, retrospective design.
Still, Turi acknowledged complete follow-up is hard to achieve over this timeframe and added PBMV still holds an important place in structural heart interventions.
“The general consensus that PMBV should be the procedure of choice for patients with symptomatic mitral stenosis and favorable anatomy is well established,” wrote Turi, with Hackensack University Hospital in New Jersey. “For the population with more complex mitral stenosis increasingly seen not just in the industrialized world but in many developing countries where rheumatic heart disease is abating, PMBV remains reasonably effective, and better and more definitive techniques, including valve in valve, are just around the corner.”
Daniel joined TriMed’s Chicago editorial team in 2017 as a Cardiovascular Business writer. He previously worked as a writer for daily newspapers in North Dakota and Indiana.