A highly detailed 3D model of a human heart anatomy, realistic medical style, showing all major parts including left and right atrium, left and right ventricle, aorta, pulmonary artery, and veins. The heart has a natural dark red color with visible muscle texture and subtle veins on the surface. Clean, smooth, and slightly glossy material. The model is anatomically accurate and proportional. Isolated on a clean white background, soft lighting, high resolution, 4K render, studio lighting, centered composition, no text, no watermark.