Degenerative mitral valve disease has doubled in prevalence globally over the last 30 years, and though improvements in surgical techniques and advances in transcatheter technologies have led to improvements in rates of mortality, these have arisen in higher income countries—leading to concern over a global disparity in care for patients with mitral valve disease.
These were among the conclusions of research presented at New York Valves 2025 (25–27 June, New York, USA), following analysis of data from the Global Burden of Disease (GBD) study—a worldwide health programme involving more than 14,000 collaborators from over 200 countries—to determine the extent of degenerative mitral valve disease from 1990 through to 2023.
Guido Ascione, a cardiac surgeon and research fellow at the Cardiovascular Research Foundation (CRF) in New York, USA, presented the data which assessed the prevalence of the disease according to population-based cohort studies, population surveys and administrative data from health facilities.
For the purposes of the study, degenerative mitral valve disease was defined as an echocardiographic finding of prolapse or myxomatous degeneration of the mitral valve with mitral regurgitation (MR) ≥2, whilst cases of secondary MR, congenital, rheumatic or those from infectious causes were excluded from the analysis.
Mortality estimates were established using information from death certificates including vital registration and autopsy data, and only cases in which degenerative mitral valve disease was the primary cause of death were taken into consideration, with estimates presented as absolute and age-standardised rates, and countries stratified based upon sociodemographic index (SDI) to determine their relative wealth.
“Primary MR progressively grew over time; from 1990 to 2023 there was a percentage increase in absolute prevalence of +126%, and in 2023 there were globally 16 million people with primary MR and at least moderate MR,” Ascione said, noting that prevalence was higher in males than in females.
Looking at age-standardised rates, Ascione commented that the data pointed to the prevalence of the disease being “actually pretty steady”, suggesting that the main driver of the increase in absolute prevalence can be ascribed to a globally ageing population or a lack of improvement in global diagnostic capabilities (i.e. access to healthcare, screening echocardiography) over the timespan of the study.
“As prevalence increases in age, the rate starts to peak after 60 years of age, and it is the highest in patients that are in between 70 and 74 years,” he detailed. “This means that in 2023, globally there were 11 million people with primary MR that were older than 70 years and four million people were actually older than 80. This has dramatic consequences when we think about treatment algorithms for the future.”
Furthermore, prevalence was shown to be greater in high-income countries compared with low-income countries, which he said could be attributed to greater diagnostic capabilities in these countries as well as the older average age of populations in these regions.
On mortality, Ascione detailed that there had been an increase in absolute number of deaths of around 75% from 1990 to 2023, with a similar trend expected up to 2050. However, age-standardised rates decreased, meaning that there has been a progressive improvement in the treatment of this disease.
“If we dig a little more into age standardised mortality rates, we can see that starting from 1990 there was a first drop in mortality, and we can clearly attribute this to a progressive improvement in surgery, with standardisation of surgical techniques, and improvement in pre- and postoperative care,” Ascione commented. “Then, after a steady state in the late 2010s, especially after 2015, there is a second drop, and this is highly probably due to the progressive rise in transcatheter technologies, that offer the treatment option to patients that were not treated before due to high surgical risk.”
However, most of the decreases in mortality had been achieved in high SDI countries, whilst in low SDI countries rates of mortality went up. “This is highly probably due to a progressive increase in diagnosis that was not followed by an improvement in treatment, and so it opens up huge opportunities for low-income countries to catch up and to fill this gap,” Ascione said.
Offering a commentary on the findings at New York Valves, Mayra Guerrero (Mayo Clinic Hospital, Rochester, USA) said the finding that degenerative mitral valve disease has increased in prevalence within an ageing population was not surprising, but said that the data highlight the anticipated “surge” in the need for mitral valve interventions coming in the future.
“We must be prepared to expand our capacity to treat these patients, but that is the easy part,” said Guerrero. “What is truly alarming is the profound spike in mortality, significantly higher among women, and in countries with low socioeconomic demographic index. While prevalence appears to be lower in these groups, mortality was not only higher, but some regions continue to increase. This raises an important concern: is that prevalence really truly lower, or is the disease under-diagnosed?”
Many patients are being under-diagnosed, under-treated, or treated too late, without access to transcatheter therapies, Guerrero said, resulting in poorer outcomes and contributing to the disproportionate rates of mortality seen in the study.
“This is not just an inconvenient truth, this is a serious and urgent problem,” she added. “Let’s treat this moment as a turning point, as a call to action to address these important healthcare disparities. In just 20 years, TAVI [transcatheter aortic valve implantation] has transformed from a bold idea into a global movement. In that spirit, I will leave that with 20 years of TEER [transcatheter edge-to-edge-repair], and almost a decade of transcatheter mitral valve replacement, we now must push to make mitral valve care a truly global movement, one that ensures accessibility, standardisation and reproducibility for all patients, regardless of sex, regardless of country of origin.”
In response to Guerrero’s comments, Ascione said that steps to reduce the disparity should begin with optimised and earlier diagnosis and identifying the patients that are most likely to benefit from treatment.
“We should come up with algorithms that account for the growing and ageing population,” he said. “Access to healthcare is a great problem, because primary MR— especially in the form of prolapse and valve disease—is clearly something that is also happening in the lower-income countries.”
Juan Granada, president and chief executive officer of the CRF and a co-author of the study, said that the data would be important to create awareness, “so that companies know what the real problem is” regarding disease prevalence.
“We have a big access problem, disparity of care, inequality in our field that needs to be addressed,” he said. Further research will be undertaken to assess the global burden of mitral annular calcification (MAC), Granada revealed.
