Clinical research study
Predictors of Ascending Aortic Dilation in Bicuspid Aortic Valve Disease: A Five-year Prospective Study

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Abstract

Background

Bicuspid aortic valves are associated with aortic dilation and dissection. There is a paucity of prospective studies evaluating changes in aortic size over time in adult subjects with bicuspid aortic valves.

Methods

A total of 115 subjects with asymptomatic bicuspid aortic valves were enrolled from 2003 to 2008 and followed prospectively over 5 years. Clinical and family histories, as well as transthoracic echocardiograms, were obtained at baseline, and echocardiograms were performed annually thereafter.

Results

The mean age of subjects was 41.8 ± 12.8 years, and 61% were male. Ascending aortic size at baseline averaged 35.5 ± 5.6 mm and increased in 71.1% of subjects (mean, 0.66 ± 0.05 mm/y; range, 0.2-2.3 mm/y) over an average of 4.8 years. In 15.6% of subjects, the rate of change exceeded 1 mm/y. The average rate of ascending aortic dilation for all subjects was 0.47 ± 0.05 mm/y (P < .001). A family history of aortic valve disease was associated with progression in both unadjusted (P = .029) and logistic regression analyses adjusted for age, gender, and body surface area (odds ratio, 13.7; P = .021). Multivariate analysis did not find leaflet orientation or moderate to severe aortic valve dysfunction as independent predictors of aortic dilation.

Conclusions

We found that in subjects with bicuspid aortic valve, studied prospectively, there was an annual rate of ascending aortic dilation of 0.47 mm/y. In contrast to previous reports, leaflet orientation and aortic valve dysfunction were not independent predictors of aortic dilation. A family history of aortic valve disease was associated with a significantly increased risk of increasing ascending aortic size.

Section snippets

Materials and Methods

This study was approved by the institutional review board of the University of Massachusetts Medical School. Between 2003 and 2008, 115 asymptomatic subjects with the echocardiographic diagnosis of bicuspid aortic valve and no prior cardiac surgery were recruited at the University of Massachusetts Medical School. Subjects gave written informed consent and underwent baseline and yearly echocardiography for 5 years. Clinical information was obtained from patient interviews at the time of

Results

Of the 115 subjects originally enrolled, 18 were excluded because of aortic valve replacement within 3 years of enrollment and 7 were excluded for <3 years of follow-up data (lost to follow-up). Ninety subjects had 3 to 5 years of follow-up data and no prior aortic valve replacement. Of these 90 subjects, 6 had subsequent valve replacements after enrollment, but had at least 3 annual echocardiograms before surgery and were included in the analysis. The interobserver reliability for measurement

Discussion

The large number of studies published in recent years on the subject of aortic dilation in patients with bicuspid aortic valves attests to the growing awareness of and interest in predicting aortic complications in these patients. The 2008 guidelines for surgical repair of aortic dilation with bicuspid aortic valves include an aortic diameter of >5 cm or diameter >4.5 cm and a yearly dilation rate >0.5 cm/y.11 Other indications include aortic diameter >4 cm in a patient undergoing elective

Conclusions

We found that among asymptomatic subjects with bicuspid aortic valves, studied prospectively, there was an annual rate of ascending aortic dilation of 0.47 mm/y, consistent with rates previously described.3, 12, 14 Given the prospective design of our study in a predefined population of asymptomatic patients with bicuspid aortic valves, these results are perhaps more generalizable within this population than those of previous retrospective reports, which may have associated biases. The majority

References (23)

  • N. Tzemos et al.

    Outcomes in adults with bicuspid aortic valves

    JAMA

    (2008)
  • Cited by (0)

    Funding: Supported in part by a grant from the Department of Medicine at the University of Massachusetts Medical School.

    Conflict of Interest: None.

    Authorship: All authors had access to the data and played a role in writing this manuscript.

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