Chapter 20: The Heart Flashcards
Artificial Pacemaker
A small, battery-operated device that keeps one’s heart beating in a rhythm. It may be permanently implanted or temporarily placed externally.
Asystole
The absence of cardiac activity with no contraction and no output.
Automated External Defibrillator (AED)
A device that, when applied, automatically checks the function of the heart. Upon detecting a condition that may respond to an electric shock, it delivers a shock to restore normal heartbeat rhythm.
Automatic Implanted Cardioverter Defibrillator (AICD)
A surgically implanted battery-operated device that monitors the function of the heart. Upon detecting a condition that may respond to an electric shock, such as disorganized heartbeat, the device delivers a shock to restore normal heartbeat rhythm.
Cardiac Arrest
Sudden stopping of the pumping action of the heart causing the loss of arterial blood pressure.
Cardiology
The branch of medicine dealing with the diagnosis and treatment of heart disorders and related conditions.
Cardiomegaly
An enlarged heart, which is a sign of some other condition such as stress, weakening of the heart muscle, coronary artery disease (CAD), heart valve problems, or abnormal heart rhythms.
Cardiomyoplasty
A surgical procedure that uses stimulated latissimus dorsi muscle to assist with cardiac functions. The latissimus dorsi muscle is relocated and wrapped around the left and right ventricles and stimulated to contract during cardiac systole by means of an implanted burst-stimulator.
Commotio Cordis
Sudden cardiac arrest as the result of a blunt hit or impact to the chest.
Congestive Heart Failure (CHF)
The heart condition of weakness, edema, and shortness of breath caused by the inability of the heart to maintain adequate blood circulation in the peripheral tissues and the lungs.
Cor Pulmonale
Weakness of the right ventricle of the heart due to prolonged high blood pressure in the pulmonary artery and right ventricle; or any disease or malfunction that affects the pulmonary circuit in the lungs.
Echocardiography
A noninvasive diagnostic test that uses ultrasound to make images of the heart chambers, valves, and surrounding structures. This diagnostic tool can also measure cardiac output, detect inflammation around the heart, identify abnormal anatomy, and dtect infections of the heart valves.
Endocarditis
Inflammation or infection of the endocardium, the inner lining of the heart muscle.
Fibrillation
Fast twitching of the heart muscle fibers with little or no movement of the muscle as a whole. Atrial fibrillation occurs in the atria of the heart and is characterized by chaotic quivers and irregular ventricular beating with both atria and ventricles being out of sync.
Heart Block
Delay in the normal electrical pulses that cause the heart to beat.
Mitral Valve Prolapse
A condition in which the mitral (bicuspid) valve cusps do not close properly and are pushed back toward the left atrium.
Myocarditis
Inflammation of the myocardium, the middle layer of the heart wall tissue.
Palpitation
Irregular and rapid beating of the heart.
Percutaneous Transluminal Coronary Angioplasty (PTCA)
The surgical use of a balloon-tipped catheter to enlarge a narrowed artery.
Sick Sinus Syndrome
A group of heart rhythm disorders or problems in which the sinoatrial node does not work properly to regulate the heart rhythms.
Aortic Sinus
Space between the superior portion of each of the three aortic valve cusps and the dilated portion of the wall of the ascending aorta.
Atrioventricular (AV) Bundle
Specialized conducting cells in the interventricular septum that carry the contracting stimulus from the AV node to bundle branches and then to Purkinje fibers; also called bundle of His.
Atrioventricular (AV) Node
Specialized cardiac muscle cells that relay the contractile stimulus to the atrioventricular bundle (bundle of His), the bundle branches, and Purkinje fibers, and the ventricular myocardium; located at the boundary between the atria and ventricles.
Atrioventricular (AV) Valves
One of the vales that prevents backflow into the atria during ventricular systole (contraction).
Auricle
A broad flattened process that resembles the external ear; in the ear, the expanded, projecting portion that surrounds the external auditory meatus; also called pinna; in the heart, the externally visible flap formed by the collapse of the outer wall of a relaxed atrium.
Bainbridge Reflex
The reflective increase in heart rate after an increase in venous return; due to mechanical and neural factors; also called atrial reflex.
Base
A compound whose dissociation releases a hydroxide ion (OH-) or removes a hydrogen ion (H1) from the solution.
Bradycardia
An abnormally slow heart rate, usually below 50 bpm.
Bundle Branches
Specialized conducting cells in the ventricles that carry the contractile stimulus from the atrioventricular bundle (bundle of His) to the Purkinje fibers.
Cardiac Cycle
One complete heartbeat, including atrial and ventricular systole and diastole.
Cardiac Outputu (CO)
The amount of blood ejected by the left ventricle each minute; normally about 5 liters.
Cardiac Reserve
The potential percentage increase in cardiac output above resting levels.
Cardiac Tamponade
A compression of the heart due to fluid accumulation in the pericardial cavity.
Chordae Tendineae
Fibrous cords that stabilize the position of the AV valves in the heart, preventing backflow during ventricular systole (contraction).
Contractility
The ability to contract possessed by skeletal, smooth, and cardiac muscle cells.
Conus Arteriosus
The conical tip of the spinal cord that gives rise to the filum terminale.
Diastole
A period of relaxation in a chamber of the heart, as part of the cardiac cycle.
Electrocardiogram (ECG/EKG)
A graphic record of the electrical activities of the heart, as monitored at specific locations on the body surface.
Endocardium
The simple squamous epithelium that lines the heart and is continuous with the endothelium of the great vessels.
Inferior Vena Cava (IVC)
The vein that carries blood from the parts of the body inferior to the heart to the right atrium.
Intercalated Discs
Regions where adjacent cardiac muscle cells interlock and where gap junctions permit electrical coupling between the cells.
Mediastinum
The central tissue mass that divides the thoracic cavity into two pleural cavities.
Mitral Valve
The left atrioventricular (AV) valve, also called bicuspid valve.
Myocardium
The cardiac muscle tissue of the heart.
Pacemaker Cells
Cells of the sinoatrial node that set the pace of cardiac contraction.
Pericardial Cavity
The space between the parietal pericardium and the epicardium (visceral pericardium) that encloses the outer surface of the heart.
Pericardium
The fibrous sac that surrounds the heart; its inner, serous lining is continuous with the epicardium.
Pulmonary Circuit
Blood vessels between the pulmonary semilunar valve of the right ventricle and the entrance to the left atrium; the blood flow through the lungs.
Purkinje Fibers
Specialized conducting cardiac muscle cells in the ventricles of the heart.
Refractory Period
The time between the initiation of an action potential and the restoration of the normal resting membrane potential; during this period, the membrane will not respond normally to stimulation.
Semilunar Valve
A three-cusped valve guarding the exit form one of the cardiac ventricles; the pulmonary and aortic valves.
Sinoatrial (SA) Node
The natural pacemaker of the heart; located in the wall of the right atrium.
Stroke Volume (SV)
The amount of blood pumped out of one heart ventricle in a single heart beat.
Superior Vena Cava (SVC)
The vein that carries blood to the right atrium from parts of the body that are superior to the heart.
Systemic Circuit
The vessels between the aortic valve and the entrance to the right atrium; the system other than the vessels of the pulmonary circuit.
Systole
A period of contraction in a chamber of the heart, as part of the cardiac cycle.
Tachycardia
Rapid heart beat, usually over 90 bpm.
