AbstractThe normal arterial and microvascular patterns of the left ventricular wall, including the papillary muscles, were studied in 54 human hearts using coronary angiography, arterial and microvascular casts, and histologic sections. According to their shapes and distributions, the arteries in the left ventricular wall may be classified as epicardial, arborized, straight, and papillary. The arborized arteries supply the whole myocardial wall, including some trabeculae carneae, and they anastomose with the straight arteries to form the subendocardial plexus. The papillary arteries have various arrangements: hooked, bifurcated, and tortuous S‐shaped. The use of histologic sections and arterial casts revealed no single central core artery and at least two arteries in each papillary muscle. The morphology and blood supply of the anterior and posterior papillary muscles varied somewhat. Scanning microscopy of the arrangement and appearance of arterioles, capillaries, and venules of the left ventricle revealed that large‐diameter capillaries, which were sometimes guarded by precapillary sphincters, arose from arterioles. The capillaries were parallel to cardiac muscle fibers and had numerous Y‐, H‐, and O‐shaped anastomotic connections. The small venules were arranged in a fan‐shaped fashion in relation to these capillaries.