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Background Sequential systolic acquisition with temporal padding is used in computed tomography coronary angiograms (CTCA) in patients with high or irregular heart rates. Early temporal acquisition images are often non-diagnostic, and we hypothesise that by shortening the temporal padding window, the acquisition window and patient radiation dose can be reduced without impacting diagnostic quality.Methods Retrospective data analysis of 50 consecutive ECG-gated, sequential systolic CTCAs undertaken at University Hospital Southampton in February to March 2025 was performed. Analysis factors such as length of acquisition, subjective best acquisition, range of usable data and dose length product (DLP). Following discussion, a consensus agreed on reducing temporal padding duration from 200ms to 130ms (table 1) by introducing a 70ms delay in scanning start time (table 2). Retrospective data analysis of 50 patients following a change in local practice was performed in January to February 2026 to determine the impact of acquisition window reduction on patient dose and diagnostic quality.Results Initial data review prior to intervention showed that a 200ms padding window could potentially be reduced without significant impairment to image quality (figure 1). Data analysis following a local change in practice demonstrated a reduction in average DLP from 137.8 to 107.0 and diagnostic images were acquired in 100% of studies (figure 2).Conclusion A reduction of padding duration in sequential systolic acquisition CTCAs can reduce patient dose while maintaining diagnostic quality. By what percentage can patient radiation dose (DLP) be reduced following a 70ms reduction in temporal padding in sequential systolic CTCAs?1. 5%2. 17%3. 22%4. 34%Abstract 16 Figure 2Abstract 16 Table 2Abstract 16 Table 1Abstract 16 Figure 15. 50%