Association Between Bicuspid Aortic Valve Phenotype and Patterns of Valvular Dysfunction and Bicuspid Aortopathy: Comprehensive Evaluation Using MDCT and Echocardiography

Study Questions:

Are patterns of cusp fusion in bicuspid aortic valves (BAVs) associated with types of aortic valve dysfunction and aortopathy?

Methods:

This study examined 167 patients with BAVs who underwent multidetector computed tomography and transthoracic echocardiography imaging as part of a presurgical evaluation. Valves were stratified as anterior-posterior orientation of cusps with fusion of the left and right coronary cusps (BAV-AP) versus left-right orientation of the cusps with fusion that included the noncoronary cusp (BAV-RL). Aortopathy was defined by the extent of aortic dilatation. The relationships between bicuspid valve morphology and valve dysfunction (stenosis or regurgitation) and extent of aortopathy were examined.

Results:

Mean age was 55 ± 14 years, and 69% were male. BAV-AP and BAV-RL morphology was observed in 56% and 44% of patients, respectively. There were no differences in mean age or gender between these groups. There were significant differences between the BAV-AP and BAV-RL groups with regard to aortic valve dysfunction (p < 0.001), with moderate to severe aortic stenosis noted in 46% and 66% of patients in these cohorts, and moderate to severe aortic regurgitation observed in 32% and 7% of patients, respectively. A significant difference in the distribution of aortopathy was also noted between these cohorts (p < 0.001), with BAV-AP associated with increased prevalence of normal aortic size and limited proximal aortic dilation, and BAV-RL associated with a higher prevalence of more extensive aortic dilation.

Conclusions:

In a cohort of patients with BAVs referred for possible surgery, there were significant differences between valve morphology and the type of aortic valve dysfunction as well as patterns of aortopathy.

Perspective:

This study adds to prior literature by examining a population of patients with BAVs referred for possible surgery. Interestingly, while the prevalence of each of the two morphology types was relatively similar, significant differences were observed in the types of aortic valve disease, with the BAV-AP and BAV-RL phenotypes associated with a greater proportion of moderate to severe aortic regurgitation and aortic stenosis, respectively. Further, significant differences in aorta morphology were also noted, with the BAV-RL cohort noted to have a higher prevalence of more distal aortic dilation. Whether these differences relate to distinct embryologic origins, or the effects of alterations in flow hemodynamics, remain unclear.

Clinical Topics: Invasive Cardiovascular Angiography and Intervention, Noninvasive Imaging, Interventions and Imaging, Computed Tomography, Echocardiography/Ultrasound, Nuclear Imaging

Keywords: Phenotype, Multidetector Computed Tomography, Dilatation, Constriction, Pathologic, Mitral Valve, Echocardiography


< Back to Listings