Assessment of a transcatheter heart valve prosthesis with multidetector computed tomography: in vitro and in vivo imaging characteristics
OBJECTIVES Percutaneous aortic valve insertion is an emerging treatment option for selected patients with severe aortic stenosis and may be done from a transfemoral or transapical approach. Concomitant atherosclerotic peripheral artery disease limits transfemoral access. We evaluated the potential role of multidetector computed tomography in preoperative assessment of vascular anatomy. METHODS Consecutive patients with severe aortic stenosis were included. Contrast-enhanced computed tomographic angiography of the thoracic and abdominal aorta and iliofemoral arteries was performed. Criteria of unfavorable iliofemoral anatomy were defined as a minimal luminal diameter of the common iliac, external iliac, or common femoral arteries of less than 8 mm, presence of greater than 60% circumferential calcification at the external-internal iliac bifurcation, and severe angulation between the common and external iliac arteries (< 90 degrees ). The prevalence of these criteria was evaluated and infrarenal aortic and iliofemoral arterial anatomy was compared in the groups with and without peripheral artery disease for any of these criteria. RESULTS One hundred patients (79 +/- 9 years, 59% male) were included. A total of 35 (35%) patients had at least one criterion of unsuitable iliofemoral anatomy, including 27 patients with small minimal luminal diameter (<8 mm), 12 patients with severe circumferential calcification at the iliac bifurcation (>60%), and 4 with severe angulation of the iliac arteries (<90 degrees ). CONCLUSIONS Significant atherosclerotic peripheral artery disease is common in the high-risk patient population currently evaluated for percutaneous aortic valve insertion. Computed tomography allows identification of patients with iliofemoral anatomy unfavorable for the transfemoral approach to percutaneous aortic valve insertion.