Background: Cardiac computed tomography (CT) imaging is the standard of care before transcatheter aortic valve replacement (TAVR) for aortic stenosis (AS). The aortic annulus undergoes conformational changes during the heart cycle, with wider aortic annulus areas during systole compared to diastole. It is known, that the image acquisition time point can impact prosthesis sizing and fit. Clinical outcome data are lacking.

Objectives: The aim of this study was to compare systolic and diastolic cardiac CT data acquisition with regard to procedural and clinical outcomes in patients undergoing TAVR for severe AS.  Methods: Preprocedural high-pitch helical CT datasets were analyzed in 1,954 patients undergoing TAVR between 2013 and 2018 at our center. Patients were retrospectively stratified into two groups according to the acquisition heart phase (979 systolic and 975 diastolic) by visual assessment.

Results: Median age was 81.6 [interquartile range 77.5-85.8] years and 964 (49.3%) patients were male. No significant difference was found for the Valve Academic Research Consortium-3 (VARC-3) endpoints of technical failure (systolic, 5.1% vs. diastolic, 5.2%, p=0.94) or device failure (systolic, 13.7% vs. diastolic, 13.5%, p=0.92). There was no difference in paravalvular regurgitation. All-cause 30-day mortality was comparable (systolic, 3.6% [95% confidence interval, 2.4-4.7%] vs. diastolic, 3.6% [2.4-4.8%], p=1.00), while 3-year mortality rates were higher in the diastolic group (Society of Thoracic Surgeons score adjusted hazard ratio, 1.25 [1.07-1.46], p<0.01). Data were consistent in the subgroups of patients with atrial fibrillation and patients receiving balloon-expandable or self-expandable valve prostheses.