Chapter 17

Vocabulary and key clinical concepts for cardiovascular emergencies based on AAOS Twelfth Edition lecture materials.

Atria

The upper chambers of the heart that receive incoming blood.

Ventricles

The lower chambers of the heart that pump outgoing blood.

Aorta

The body's main artery, which receives blood ejected from the left ventricle.

Automaticity

A property that allows heart muscle cells to contract spontaneously without a stimulus from a nerve source.

Autonomic Nervous System (ANS)

The part of the nervous system that controls involuntary activities and is divided into the sympathetic and parasympathetic systems.

Cardiac Output

The volume of blood that passes through the heart in $1\,\text{minute}$, calculated by multiplying heart rate and stroke volume.

Perfusion

The constant flow of oxygenated blood to the body's tissues.

Ischemia

A condition of decreased blood flow, typically causing chest pain due to a lack of oxygen reaching the tissues.

Atherosclerosis

A disorder characterized by the buildup of calcium and cholesterol inside the walls of blood vessels.

Thromboembolism

A blood clot that floats through the blood vessels until it reaches an area too narrow for it to pass, causing an obstruction.

Acute Coronary Syndrome (ACS)

A group of symptoms caused by myocardial ischemia, including angina pectoris and acute myocardial infarction.

Angina Pectoris

Chest pain that occurs when the heart's need for oxygen exceeds the available supply.

Acute Myocardial Infarction (AMI)

The death of heart muscle cells due to a lack of blood flow; once dead, these cells cannot be revived.

Syncope

A medical term for fainting.

Dyspnea

A medical term describing shortness of breath.

Dysrhythmia

An abnormality of the heart rhythm, such as tachycardia, bradycardia, or ventricular fibrillation.

Asystole

The complete absence of all electrical activity in the heart, typically resulting in death.

Cardiogenic Shock

A condition usually caused by a heart attack where the heart lacks the power to force enough blood through the circulatory system.

Congestive Heart Failure (CHF)

A condition following a heart attack where the heart's pumping function is decreased, leading to fluid congestion in the lungs or dependent edema.

Hypertensive Emergency

A clinical situation characterized by a systolic blood pressure greater than $180\,\text{mm Hg}$.

Aortic Aneurysm

A weakness in the wall of the aorta that makes it susceptible to rupture.

Dissecting Aneurysm

A condition where the inner layers of the aorta become separated, allowing blood to flow between them at high pressure.

Aspirin

A medication that prevents blood clots from forming or enlarging; the recommended dose for cardiac emergencies is $162\,\text{mg}$ to $324\,\text{mg}$ using $81\,\text{mg}$ chewable tablets.

Nitroglycerin

A vasodilator used to relax blood vessel walls and increase oxygen supply to the heart, contraindicated if systolic blood pressure is below $100\,\text{mm Hg}$.

Coronary Artery Bypass Graft (CABG)

A surgical procedure where a blood vessel from the chest or leg is sewn from the aorta to a coronary artery to bypass an obstruction.

Percutaneous Transluminal Coronary Angioplasty

A procedure involving the inflation of a tiny balloon inside a narrowed coronary artery to improve blood flow.

Left Ventricular Assist Device (LVAD)

A mechanical pump used to enhance the pumping of the left ventricle in patients with severe heart failure.

Cardiac Arrest

The complete cessation of cardiac activity, indicated by the absence of a carotid pulse.

Automated External Defibrillator (AED)

A device that analyzes electrical signals from the heart and administers a shock to treat ventricular fibrillation.