Higher AVC scores reflective of greater risk of severe aortic stenosis: JACC
USA: A recent study has found the risk of severe aortic stenosis (AS) to be exponentially higher with higher aortic valve calcification (AVC) scores, whereas AVC=0 was tied to an extremely low long-term risk of severe AS. AVC measurement provides clinically relevant information to evaluate an individual's long-term risk for severe AS.
The study, published in JACC: Cardiovascular Imaging, found only 13% of patients free of known cardiovascular disease (CVD) had AVC >0, and there were significant associations of AVC with gender, age, and race/ethnicity.
Previous studies have shown aortic valve calcification (AVC) being a principal mechanism underlying aortic stenosis. Therefore, Seamus P. Whelton, Johns Hopkins School of Medicine, Baltimore, Maryland, USA, and colleagues aimed to determine the AVC prevalence and its association with the long-term risk for severe AS.
For this purpose, the researchers performed non-contrast cardiac computed tomography in 6,814 participants free of known CVD at a Multi-Ethnic Study of Atherosclerosis (MESA) visit. Agatston method was used to quantify aortic valve calcification, and normative sex-, age-, and race/ethnicity-specific AVC percentiles was derived. A chart review of all hospital visits was done to adjudicate severe AS. Multivariable Cox HRs were used to evaluate the association between AVC and long-term incident severe AS.
The study led to the following findings:
- AVC was present in 913 13.4% of the participants.
- The probability of AVC >0 and AVC scores increased with age and was generally highest among men and White participants.
- Generally, the probability of AVC >0 among women was comparable to men of the same ethnicity/race who were approximately ten years younger.
- Over a median follow-up of 16.7 years, incidents adjudicated severe aortic stenosis occurred in 84 participants.
- Higher AVC scores were exponentially linked with the absolute risk and relative risk of severe aortic stenosis with adjusted HRs of 380.9, 76.4, and 12.9 for AVC groups ≥300, 100 to 299, and 1 to 99, compared with AVC = 0.
"Our study is the first to establish an association between an individual's AVC score and their long-term risk of developing severe AS," the researchers wrote.
"It is not surprising that this risk raised with higher calcium score, although the exponential increase in HR observed across AVC categories in this study was quite impressive," they added. "At the same time, the findings and clinical implications are somewhat muted in the absence of viable decalcification strategies."
"Of immediate clinical significance is the finding that patients with an AVC of 0 had almost no risk of severe AS development in the long-term," they noted.
"There is a need to verify these findings in additional studies, but it could lead to practice change, particularly if AVC could be included as a standard measurement in CT scans to evaluate coronary calcium," they concluded.
Reference:
Whelton SP, Jha K, Dardari Z, Razavi AC, Boakye E, Dzaye O, Verghese D, Shah S, Budoff MJ, Matsushita K, Carr JJ, Vasan RS, Blumenthal RS, Anchouche K, Thanassoulis G, Guo X, Rotter JI, McClelland RL, Post WS, Blaha MJ. Prevalence of Aortic Valve Calcium and the Long-Term Risk of Incident Severe Aortic Stenosis. JACC Cardiovasc Imaging. 2023 Mar 30:S1936-878X(23)00115-8. doi: 10.1016/j.jcmg.2023.02.018. Epub ahead of print. PMID: 37178073.
