Advantages of nitroglycerin application in preoperative CTA for DIEP flap breast reconstruction

The purpose of this study was to investigate the advantages of nitroglycerin in preoperative computed tomography angiography (CTA) for deep inferior epigastric perforator (DIEP) flap-based breast reconstruction (BR). The aim is to provide a more reliable preoperative vascular assessment method for DIEP flap BR and expand the clinical application options of nitroglycerin. Patients scheduled for BR with DIEP flap were admitted from February 2022 to October 2025. They were randomly divided into the nitroglycerin group and the control group in a ratio of 1:1, using a random number method. The nitroglycerin group received sublingual nitroglycerin tablets 0.5 mg 5 min prior to CTA scanning, while the control group received no intervention. The two groups completed the preoperative CTA examination under the same scanning parameters. The diameter, CT value, number of perforators, and perforator branch grade of the inferior epigastric artery (IEA) were measured and compared between the two groups. Additionally, the consistency between preoperative and intraoperative selection of dominant perforators were analyzed in both groups, with assessments based on three dimensions: side (left/right), row (medial/lateral), and number of perforators. And collect the complications and satisfaction rates of patients after BR surgery, and conduct a comparative analysis. In this study, a total of 58 patients were finally included in the analysis, including 32 in the nitroglycerin group and 26 in the control group. No statistically significant differences were observed in baseline characteristics between the two groups (P > 0.05). The diameter of left IEA (2.40 mm vs. 1.95 mm, P = 0.007), the diameter of right IEA (2.44 mm vs. 2.03 mm, P = 0.020), the number of perforator (16 vs. 12, P = 0.002), the CT value of left IEA (674.00Hu vs. 343.00Hu, P < 0.001), the CT value of right IEA (718.00Hu vs. 362.50Hu, P < 0.001) and the branch grade of perforator (4 vs. 3, P = 0.011) in the nitroglycerin group were higher than the control group, and the difference was statistically significant. However, there were no statistically significant differences between the two groups in the consistency of dominant perforator selection regarding side (left/right), row (medial/lateral), or number of perforators (all P > 0.05). The complication rate of the control group was slightly higher than the nitroglycerin group (50.0% vs. 46.9%, P = 0.813), and the difference was not statistically significant. In terms of satisfaction with BR, the nitroglycerin group was slightly higher than the control group, but this difference was not statistically significant. Nitroglycerin can dilate the diameter of the IEA, improve the image quality of the CTA, and provide surgeons with more detailed anatomical information of the DIEP flap, which will be beneficial for the surgeon to locate the dominant perforator and design the flap prior to surgery.