Author + information
- Ashutosh Hardikar, MBBS and
- Thomas H. Marwick, MBBS, PhD, MPH∗ ()
- ↵∗Menzies Research Institute Tasmania, Private Bag 23, Hobart, 7000, Australia.
We would like to thank Drs. Girdauskas and Borger for their interest and comments regarding our paper (1). We also concur regarding the main message of the meta-analysis, which is that aortopathy associated with bicuspid aortic valve has very low adverse event rates—contrary to the perception that this disease is analogous to connective tissue disorders. This main finding is not compromised by the heterogeneity of the literature.
The significant heterogeneity in the literature is not restricted to aortic stenosis and regurgitation, but also involves bicuspid aortic valve morphologies, as well as the nature of the underlying tissue. Indeed, we found that aortic regurgitation was reported in an older age group—had we focused on aortic valve repair publications, we would have an entirely regurgitant population subset. Similarly, had we taken a subgroup of publications from younger age groups, we would have had a stenosis-predominant subset. Only a few authors have looked at stenosis only (2), and hence, it was difficult to compare these subsets without the heterogeneity. An individual patient meta-analysis would overcome the dependence of standard meta-analysis on the case-mix of the original data, but the performance of this would require more effective data archiving than is the current practice.
We agree that the relationship of age with aortic diameter could be confounded by other factors (3,4). However, as those factors also change with age, we thought that age might be a reasonable marker to increase the clinician’s alertness. We hope that once we have sufficient longitudinal data from registry studies, these relationships could be analyzed with more accuracy.
- American College of Cardiology Foundation
- Hardikar A.A.,
- Marwick T.H.
- Davies R.R.,
- Kaple R.K.,
- Mandapati D.,
- et al.