Fig 1.
The left coronary artery was permanently ligated 2 mm distal to (A) or immediately below (B) the LAA. A catheter with an internal diameter of 0.89 mm was inserted from the right carotid artery into the aortic root (C). The septal artery invariably branched off either from proximal part of the LCA (n = 30, 60%) (D) or RCA (n = 20, 40%) (E). Representative histological images of left and right ventricular cavities at the level of the papillary muscles in normal rats (F). Abbreviations: LV = left ventricle, LAA = left atrial appendage, CCA = carotid coronary artery, PI = peripherally inserted, LCA = left coronary artery, RCA = right coronary artery, RV = right ventricle, LAD = left anterior descending artery, LCX = left circumflex artery, APM = anterior papillary muscle, PPM = posterior papillary muscle.
Fig 2.
There are 3 branching patterns of LCX, which arose distally from a long LMCA (A, B), proximally from a short LMCA (C, D), or the septal artery (E, F).
Abbreviations, see Fig 1, LMCA = left main coronary artery.
Fig 3.
The representative histological and angiographic findings of the 2 rats in which the coronary artery was ligated 2 mm distal to the LAA (A-C and D-F).
Both cases showed myocardial infarction localized to anterior territory with intact LCX and septal artery. The size of myocardial infarction was 33% (A), and 26% (C), respectively. Abbreviations, see Figs 1 and 2.
Fig 4.
The representative histological and angiographic findings of the 4 rats in which the coronary artery was ligated immediately below the LAA (A-I). The former 2 rats showed myocardial infarction localized to anterior territory with intact LCX (A-C and D-F), while the latter 2 showed broad myocardial infarction involving anterior and lateral territories (G-I and J-L). The size of myocardial infarction was 35% (A), 27% (D), 51% (G), and 53% (J), respectively. The territory of the septal artery was not affected in any of the rat models of myocardial infarction. Abbreviations, see Figs 1 and 2.
Fig 5.
Scatter plot showing size of myocardial infarction (A), LV end-systolic dimension (B), and LV ejection fraction (C) in the models in which the LCA was ligated distally versus proximally.
Fig 6.
Relationship between the size of myocardial infarction and LV end-diastolic dimension (A), LV end-systolic dimension (B), and LV ejection fraction (C).
The black circles indicate the models in which the coronary artery was ligated 2 mm distal to the LAA and the white circles indicate the models in which the LAD was ligated immediately below LAA.