Reduction of contrast volumes for CCTA of the AVA can be achieved by using lower flow rates than for coronary CT angiography. Although 5 mL/s is typically recommended for coronary imaging, 3 mL/s may sometimes be sufficient for imaging patients in the workup for TAVR.2 Though suggested, these CCTA lower flow rates have not been systematically performed and validated in a population being evaluated for candidacy for TAVR. And as recommended by guidelines, a standard bolus of 80 mL to 120 mL of low-osmolar iodinated contrast is usually necessary for optimal TAVR CCTA scanning.1 In these patients, reducing the dose of iodinated contrast at the time of CCTA acquisition in an attempt to minimize renal injury, and at the same time being able to accurately assess the aortic annulus apparatus (AVA) will be of paramount importance. Some reduction of contrast nephropathy can be accomplished by minimizing contrast volume and the use of iso-osmolar or low-osmolar contrast agents. It has been suggested that the contrast volume threshold can be estimated by using the ratio of contrast volume to creatinine clearance. Nephrotoxicity is more likely when the contrast volume/creatinine clearance ratio exceeds 3.7:1.12 And using this, 3.7 x eGFR (estimated glomerular filtration rate) can be set as the maximal contrast dose for an imaging test or invasive procedure.12 14 CCTA acquisition methods Images were acquired with a Brilliance 64-slice CT scanner (Philips Healthcare, Andover, Massachusetts, USA). As per the recommendations on radiation protection in cardiovascular CT by the Society of Cardiovascular Computed Tomography (SCCT), a tube potential of 100 kV will be considered for patients weighing <90 kg or with a body mass index (BMI) <30; whereas a tube potential of 120 kV will be considered for patients weighing >90 kg and with a BMI >30. It will be adjusted, based on each individual patient's size, to the lowest setting that guarantees acceptable image noise for a suitable signal-to-noise ratio (SNR) to perform analysis.15 The patients' eGFR was first calculated using the MDRD (modification of disease in renal diet) GFR formula. The maximal allowable contrast dose for the CCTA was calculated using 3.7 x [(patient's BSA/1.73) x MDRD-eGFR].14 Next, the dose of contrast chosen for the CCTA was < 50% of the maximal allowable contrast dose. The MDRD formula can underestimate the GFR by about 6.2% in patients with chronic kidney disease and by about 29% in healthy individuals, making this an extremely suitable conservative approach for calculating the contrast dosing, with a tendency only to underdose and never to overdose the contrast. With our extensive experience in doing this, we have decreased the total contrast dose for CCTA of the AVA to 45 ml with satisfactory image quality and SNR for post-processing.