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Figure 2 Origin of the LAD from the RCA crossing the right ventricular outflow tract. (A) High parasternal short-axis view. The enlarged proximal RCA supplies the LAD. (B) Leftward angled parasternal long-axis view profiling the right ventricular outflow tract (infundibulum) free wall. The LAD is seen in cross-section approximately 7 mm below the pulmonary valve. A = anterior; AoV = aortic valve; Inf = infundibulum; L = left; LAD = left anterior descending coronary artery; MPA = main pulmonary artery; RCA = right coronary artery; R/S = right/superior.