The bicuspid valve patient with a modestly dilated ascending aorta: the crossroad between surveillance and preventive surgery

Objectives: Bicuspid aortic valves (BAV) are frequently associated with root/ascending aorta (AA) dilation, but there is controversy regarding when to operate to prevent dissection of a dilated aorta associated with a well-functioning BAV. Methods: 158 patients (mean age: 56±14 years) with a dilated ascending aorta and well-functioning BAV were studied from 1988–2008. All patients underwent CT scanning and digitilization to calculate cross-sectional area of AA and mean diameter. 42 patients underwent operation after initial CT scan (mean AA diameter 5.6±0.5cm). 116 patients (mean diameter 4.6±0.5cm) were enrolled in annual or semi-annual surveillance. Results: Average follow-up was 6.5±4.1years. Overall survival after the first encounter was 93% at 5 years and 85% at 10 years. 87/158 patients had a Bentall/Yacoub procedure, with one hospital death (1.1%). Mean duration of surveillance in the 116 patients without immediate operation was 4.2±2.9 years (481 patient-years). Average growth rate of the AA in patients ≥2 scans was 0.77mm/year (p< .0001 vs. normal population with no significant impact of hypertension, sex, smoking or age. 45 of the 116 surveillance patients underwent operation after a mean of 3.4±2.9 years (mean age 55±15years; mean AA diameter 4.9±0.6cm). 6 patients died without surgery – mean age 81±8.1 years – but none within one year of the last CT scan. Conclusions: Significant albeit moderate progressive dilatation occurs in most patients with AA <5cm and well-functioning BAV. Surveillance with appropriately timed surgery does not result in mortality if CT scans are performed at least annually.