Rapid growth of thoracic aortic aneurysm: Reality or myth?

OBJECTIVES

The American Association for Thoracic Surgery 2010 guidelines stipulate that rapid growth of the aorta (>3 mm/y) is an indication for prophylactic surgical intervention. Because of the many potential sources of error in aortic measurement (including measurement variability and comparison of noncorresponding segments), we explored whether rapid aortic growth was a reality or a falsehood.

METHODS

Among 2781 patients with aortic disease who were treated over 3 decades, we examined aortic growth rate in 811 patients with at least 2 aortic images taken at least 2 years apart. We identified 42 ascending and 27 descending patients with putative rapid aortic growth. A team of experienced clinicians reread the source images.

RESULTS

Among the 42 ascending patients with putative rapid aortic growth, rapid growth was confirmed in 12 and refuted in 11 (19 images nonretrievable). Among the 27 descending patients, rapid growth was confirmed in 6 and refuted in 4 (17 images nonretrievable). We calculated lower, middle, and highest possible rapid growth rates by prorating positivity rates for nonretrievable scans. Lowest, middle, and highest possible rates of rapid growth were 2.7%, 4.7%, and 6.9% for ascending aorta, and 1.6%, 4.3%, and 7.3% for descending aneurysms, respectively. Middle rates are considered most accurately reflective. Of the patients with confirmed rapid growth, 3 of 4 inoperable patients succumbed to their aorta. Twenty-three patients underwent prompt surgery, with 22 survivors. For the rapidly growing aortas, operative, pathologic, and genetic findings are reported.

CONCLUSIONS

Although not a falsehood, rapid growth is uncommon for the ascending and descending aorta. Many putative cases are reflective of measurement error. Attention to potential sources of measurement error is key. VIDEO ABSTRACT.