Understanding Medical Surgical Nursing Chapter 21

Epicardium - Inner membrane on the surface of the heart muscle Myocardium - Cardiac Muscle Pericardium - Outer membrane (sac around the heart) Serous fluid - Is between the parietal and visceral layers; prevents friction as the heart beats Parietal Membrane - Middle layer What lines the myocardium? - Epicardium which prevents abnormal clotting Vena Cava - 1st Right Atrium - 2nd Tricuspid Valve - 3rd Right Ventricle - 4th Pulmonic Valve - 5th Pulmonary Artery - 6th Lungs - 7th Pulmonary Veins - 8th Left Atrium - 9th Mitral Valve - 10th Left Ventricle - 11th Aortic Valve - 12th Aorta - 13th Rest of the body - 14th What part of the heart pumps with the most force? - Left ventricle SA Node (Sinoatrial) - Pacemaker initiates heartbeat at about 100 beats per minute and 75 at rest (even lower for athletes) AV Node - Backs up the SA node at 40-60 beats per minute