乌鸦传媒

Undiagnosed heart valve disease was highly prevalent in a large community study of otherwise healthy people recruited from primary care in the U.K., researchers found.

There was a 28.2% prevalence of mild, moderate, or severe asymptomatic valvular heart disease in older people with no previously known heart disease and no prior indication for echocardiography -- the prevalence increasing stepwise with age from 21.2% in the 60-64 age group to 31.5% at age 70-74 to 53.6% at age 85 and older, according to Vassilios Vassiliou, MBBS, PhD, of the University of East Anglia in Norwich, England, and colleagues.

Older age was the single most important risk factor for valve disease that Vassiliou's group found (OR 1.07 per 1-year increment, 95% CI 1.05-1.09), the authors reported in .

People over 75 years old had a 6.7% prevalence of clinically significant, moderate or severe valve disease -- well above the 2.4% rate across the larger pool of people 60 and older.

In the end, the investigators estimated that the number needed to scan to diagnose one clinically significant case of valvular heart disease was 42 for people over 60 and 15 for those at least 75 years old.

"As our population ages, this information can help healthcare providers understand the scale of valve disease and streamline routine care methods and screening programs to ensure that we can cope with the demand in the future," Vassiliou said in a .

"In the era of cost-effectiveness, and focused echocardiography using portable echocardiographic machines, these figures can be considered by policy makers to identify whether screening for heart valve disease can be cost-effective," study authors wrote.

Wider screening for heart valve disease would theoretically allow more people to get an earlier diagnosis and start medical therapy and risk factor modification.

Currently, referrals for echocardiographic screening of valve disease are based on symptoms or abnormal cardiac auscultation.

"This can be challenging in the elderly because mild symptoms may be masked by reduced physical activity and impaired mobility. In addition, cardiac auscultation has demonstrated limited accuracy for the detection of VHD [valvular heart disease] in asymptomatic elderly patients, and is thus a poor diagnostic screening tool in primary care," according to the authors. "As a result, there may be a significant proportion of VHD that remains undiagnosed in this population."

Notably, this report did not count trivial regurgitation and aortic sclerosis in the definition of valve disease, and it also excluded people with atrial fibrillation.

This meant that the patient pool was different from that of the older study, which reported a prevalence of asymptomatic and previously undiagnosed valve disease exceeding 50% in the primary care setting.

"These valuable data can lay the foundation for further epidemiological studies evaluating the burden of VHD in the community and the potential role of echocardiographic screening in the elderly population," Vassiliou and colleagues maintained.

Their prospective cohort study was based on 10,000 people who had been recruited from 2007 to 2016 through general practices in England's West Midlands and Norfolk areas and Aberdeenshire in Scotland. Among them, 4,237 asymptomatic volunteers with no prior indication for echocardiography and no known cardiac disease were eligible for inclusion in the study.

This was a cohort averaging 69.1 years old, with 54.2% women and 97.7% reporting white race. Median blood pressure was 142.8/79.5 mm Hg. The mean BMI was 26.9, and 70.8% were overweight. The most common modifiable cardiovascular risk factors were hypertension (36.4%), hypercholesterolemia (24.4%), smoking (9.7%), and diabetes (7.8%).

Participants agreed to fill out a questionnaire and undergo clinical examination and transthoracic echocardiography. Most scans were performed by two experienced sonographers.

The most commonly encountered valve conditions were tricuspid regurgitation (13.8%), mitral regurgitation (12.8%), and aortic regurgitation (8.3%).

The investigators reported that 63.6% of flagged cases involved isolated single valve disease.

There were no cases of pulmonary or tricuspid stenosis detected. Cardiac tumors were incidentally found in a few cases: two atrial myxomas and one aortic fibroelastoma.

Selection bias was a potential limitation of the observational study. Another caveat was the questionable generalizability of findings to other communities with different ethnic makeup. Additionally, the authors said they were unable to incorporate BNP/NT-proBNP values in the study.

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