Transfemoral access assessment for transcatheter aortic valve replacement: evidence-based application of computed tomography over invasive angiography.

BACKGROUND: Although computed tomography (CT) is commonly used for iliofemoral evaluation for transfemoral transcatheter aortic valve replacement, many centers worldwide use invasive angiography alone for this purpose. No study to date has evaluated the value of CT over angiography for the prediction of vascular complications. In addition, no data exist for the value of noncontrast CT.

METHODS AND RESULTS: Of the 588 transcatheter aortic valve replacement patients, we reviewed 496 consecutive transfemoral cases. Vessel diameters were measured by CT or angiography. Sheath-related complication (SRC) was defined as an iliofemoral arterial injury not including a cannulation site. Receiver operating characteristic models were generated using sheath-to-iliofemoral artery ratios as a variable and SRC as an end point. In patients undergoing both contrast CT and angiography (n=283; 35 SRCs), contrast CT showed a greater predictive value than angiography by area under the curve P<0.001): 0.87 (95% confidence interval: 0.82-0.91) versus 0.72 (95% confidence interval: 0.66-0.77). In patients undergoing both noncontrast CT and angiography (n=103; 17 SRCs), there was no difference between noncontrast CT and angiography: 0.79 (95% confidence interval: 0.70-0.86) versus 0.73 (95% confidence interval: 0.63-0.81). Three-dimensional assessments of calcification and tortuosity provided limited additional value for SRC prediction.

CONCLUSIONS: Contrast CT has a greater predictive value for post-transcatheter aortic valve replacement vascular complications than angiography. Because these complications increase mortality, an accurate assessment of the vasculature is a critical component of proper access selection.