a comprehensive 3d cutaway of the human heart unveiling the intricate anatomy and function of the

anatomical blood cardiovascular cell diagram endocardium epicardium internal left atrium ventricle myocardium myofibril myosin pacemaker pulmonary right saculoidal sarcoplasmic reticulum skeletal tissue trabecular valve ventricular xray circulatory system oxygenation nutrient delivery cardiac muscle cardiomyocyte vessels heart valves physiology medical education healthcare human anatomy circulation systemic coronary arteries veins atrioventricular node sinoatrial