Synchronisation between contrast media administration and caudocranial scan direction increases visualisation of altered coronary artery blood flow in patients presenting with dual left anterior descending coronary artery

Figure 1.. (a–d)schematic diagrams demonstrate four types of dual LAD. The first four subtypes were described by Spindola-Franco et al.2 Dashed lines indicate the AVIS septum. A, ascending aorta; AVIS, anterior interventricular sulcus; D, diagona1 coronary artery; LCX, left circumflex artery; LM, left main coronary artery; RCA, right coronary artery; S, septal coronary artery; S LAD, short left anterior descending artery; L LAD, long left anterior descending artery; LCX, left circumflex artery.

Figure 2.. (a–c) Schematic (a), 3D volume rendering (b) and (c) 3D globe view illustration of our novel dual LAD. Dashed lines indicate the AVIS septum. A, ascending aorta; AVIS, anterior interventricular sulcus; D, diagona1 coronary artery; LCX, left circumflex artery; L LAD, long left anterior descending artery; LM, left main coronary artery; RCA, right coronary artery; S, septal coronary artery; S LAD, short left anterior descending artery.

Figure 3.. 3D volume rendering of the heart with the pulmonary artery origin digitally excised showing the course of the S LAD along the epicardial surface of the LV reaching the apex, and the L LAD along the epicardial surface of the RV and into the distal AIVG. A, ascending aorta; D, diagona1 coronary artery; L LAD, long left anterior descending artery; LCX, left circumflex artery; LM, left main coronary artery; LMCA, left main coronary artery; LV, left ventricular; RCA, right coronary artery; RV, right ventricular; S, septal coronary artery; S LAD, short left anterior descending artery.

Figure 4.. The timing bolus is used to determine the TTP of the descending thoracic aorta. Therefore, in this case study, we synchronized our CTA acquisition when we reached peak contrast opacification in the descending thoracic aorta which accounts for maximal filling of the RCA, dual LAD and LCX. CTA, CT angiography; HU, Hounsfield units; LCX, left circumflex artery; LAD, left anterior descending; RCA, right coronary artery; TTP, time to peak.

Figure 5.. This image demonstrates the optimal time to begin the CTA acquisition relative to the contrast media opacification profile. The dotted lines with the arrows demonstrate the arterial blood flow direction, whereas the scan acquisition is in the caudocranial direction (long white arrow). The opacification profiles demonstrate the scan phase relative to the contrast opacification curve at each anatomical location. The first curve demonstrates the scan acquisition box at the level of descending aorta, whereas the last curve (relative to the end of the scan direction), shows the proximal coronary artery scan phase during the opacification profile. AA, ascending aorta; CTA, CT angiography; LAD, left anterior descending artery; LCX, left circumflex artery; LM, left main coronary artery.