Vascular calcification protects against progressive abdominal aortic aneurysm expansion, study suggests
Austria: Increased vascular calcification is associated with a significant decrease in aneurysm growth over time, suggests a recent study in the Journal of Vascular Surgery.
The researchers found that increased vascular calcification stabilized the aortic aneurysmal wall and likely provided protection against progressive expansion of abdominal aortic aneurysm (AAA), leading to a significant decrease in aneurysm growth over time. This as a consequence may have implications for rupture risk, morbidity, mortality, and cost.
Currently, the only clinically applied predictor of abdominal aortic aneurysm progression is the maximal aortic diameter. It is known that the rupture risk is associated with aneurysm size; hence, it becomes critical that AAA expansion be accurately monitored. Aneurysmal vessel wall calcification and its implication on AAA expansion are not explored well.
Considering the above, Wolf Eilenberg, University Hospital Vienna, Medical University of Vienna, Vienna, Austria, and colleagues aimed to evaluate the vascular calcification using longitudinal computed tomography angiographies (CTA) of patients with an AAA and its association with AAA growth.
For this purpose, the researchers performed a retrospective study of 102 patients with an AAA with a total of 389 abdominal CTAs at 6-month intervals, treated and followed at the Division of Vascular Surgery, Department of General Surgery, Medical University of Vienna. A review of digitally stored CTAs was done for vascular calcification (volume and score) of the infrarenal aorta and common iliac arteries as well as for morphometric AAA analysis.
Slow versus fast AAA progression was defined as a less than 2 mm or a 2-mm or greater increase in AAA diameter over 6 months in the prognostic setting. A specifically tailored log-linear mixed model was used for examining the association of vascular calcification and the AAA growth rate with longitudinal monitoring data.
The findings of the study were as follows:
· An inverse relation of increased abdominal vessel wall calcification and short-term AAA progression was detected.
· Compared with fast progressing AAA, the median calcification volume of the infrarenal aorta (1225.3 mm³ vs 519.8 mm³), the median total calcification volume (2014.1 mm³ vs 1434.9 mm³), and the median abdominal total customized Agatston calcium (cAC) score (1663.5 vs 718.4) were significantly increased in slow-progressing AAA.
· A log-linear mixed model efficiently predicted AAA expansion based on current diameter and abdominal total cAC score.
To conclude, the researchers observed a protective effect of increased CTA-measured vascular calcification on AAA progression. Fast AAA progression over short-term periods of 6 months may be identified by vascular calcification.
"As a pathological implication, it is indicated that vascular calcification stabilizes the aortic aneurysmal wall and protects against progressive AAA expansion," wrote the authors. "This data may have an impact on patient awareness of disease risk, clinical decision-making, and could lead to an associated decrease in rupture risk, mortality, morbidity, and cost."
Reference:
Klopf J, Fuchs L, Schernthaner R, Domenig CM, Gollackner B, Brostjan C, Neumayer C, Eilenberg W. The prognostic impact of vascular calcification on abdominal aortic aneurysm progression. J Vasc Surg. 2022 Jun;75(6):1926-1934. doi: 10.1016/j.jvs.2021.11.062. Epub 2021 Dec 16. PMID: 34921970.
