Cardiac Anatomy and Physiology Overview

This set of vocabulary flashcards covers the essential terms and definitions from the lecture notes on cardiac anatomy, physiology, pathology, and electrophysiology. Use them to reinforce key concepts and prepare for exams.

Plasma

Liquid portion of blood (≈55%) that helps prevent bleeding and transports nutrients, hormones, and waste.

Red Blood Cells (Erythrocytes)

Cells that make up ≈45% of blood; contain hemoglobin to carry oxygen.

White Blood Cells (Leukocytes)

Immune cells found in a small percentage of blood that defend against pathogens.

Platelets (Thrombocytes)

Cell fragments involved in blood clotting.

Hemoglobin

Oxygen-carrying protein in red blood cells; contains iron-based heme groups for reversible O₂ binding.

Arteries

Vessels that carry oxygenated blood away from the heart and have thick, elastic walls.

Capillaries

Microscopic vessels where gas, nutrient, and waste exchange occurs between blood and tissues.

Veins

Vessels that return deoxygenated blood to the heart; contain valves to prevent backflow.

True Ribs (1-7)

First seven pairs of ribs that directly attach to the sternum via their own costal cartilages.

False Ribs (8-11)

Ribs that connect to the sternum indirectly or not at all; include floating ribs.

Sternum

Flat bone at the center of the chest protecting mediastinal organs.

Costal Cartilages

Bars of hyaline cartilage connecting ribs to sternum and providing chest flexibility.

Mediastinum

Central thoracic cavity containing the heart, esophagus, trachea, major vessels, and thymus.

Base of the Heart

Broad superior portion where major vessels enter and leave.

Apex of the Heart

Pointed inferior tip of the heart.

Right Atrium

Heart chamber receiving deoxygenated blood from superior vena cava, inferior vena cava, and coronary sinus.

Superior Vena Cava

Large vein returning blood from upper body to right atrium.

Inferior Vena Cava

Large vein returning blood from lower body to right atrium.

Coronary Sinus

Venous channel draining deoxygenated blood from myocardium into right atrium.

Left Atrium

Chamber receiving oxygenated blood from four pulmonary veins.

Pulmonary Veins

Vessels that carry oxygenated blood from lungs to left atrium.

Right Ventricle

Chamber pumping deoxygenated blood into the pulmonary trunk toward the lungs.

Pulmonary Trunk

Artery leaving right ventricle that splits into right and left pulmonary arteries.

Pulmonary Arteries

Arteries transporting deoxygenated blood to lungs for oxygenation.

Left Ventricle

Thick-walled chamber pumping oxygenated blood into the aorta and systemic circulation.

Aorta

Largest artery carrying oxygenated blood from left ventricle to the body.

Epicardium (Visceral Pericardium)

Outer layer of heart wall providing protection and lubrication.

Myocardium

Middle, muscular layer responsible for heart contractions.

Endocardium

Inner endothelial lining that prevents clotting and lines valves.

Pericardium

Double-walled sac surrounding the heart, consisting of fibrous and parietal layers, providing protection and lubrication.

Fibrous Pericardium

Tough outer layer of the pericardium anchoring the heart in the thorax.

Parietal Pericardium

Inner layer of pericardial sac lining the fibrous pericardium.

Pericarditis

Inflammation of the pericardium causing sharp, stabbing chest pain; often viral.

Coronary Arteries

Vessels encircling the heart and supplying oxygenated blood to myocardium.

Right Coronary Artery (RCA)

Coronary vessel branching into the posterior descending and right marginal arteries.

Posterior Descending Artery

Branch of RCA supplying posterior interventricular septum and ventricles.

Right Marginal Artery

RCA branch supplying right ventricular wall.

Left Coronary Artery (LCA)

Main coronary vessel branching into left anterior descending, left circumflex, and left marginal arteries.

Left Anterior Descending (LAD) Artery

LCA branch supplying anterior interventricular septum and ventricles.

Left Circumflex Artery

LCA branch coursing around left atrioventricular groove to supply left atrium and ventricle.

Left Marginal Artery

Branch of left circumflex supplying lateral left ventricle.

Coronary Artery Disease (CAD)

Condition of atherosclerotic plaque buildup in coronary arteries reducing blood flow.

Atherosclerosis

Accumulation of lipid-rich plaques in arterial walls.

Ischemia

Inadequate blood supply to tissues leading to oxygen shortage.

Angina Pectoris

Chest pain resulting from myocardial ischemia.

Atrioventricular (AV) Valves

Tricuspid and mitral valves located between atria and ventricles.

Tricuspid Valve

Right AV valve with three cusps.

Bicuspid (Mitral) Valve

Left AV valve with two cusps.

Semilunar Valves

Pulmonary and aortic valves located at ventricular outflow tracts.

Pulmonary Valve

Semilunar valve between right ventricle and pulmonary trunk.

Aortic Valve

Semilunar valve between left ventricle and aorta.

Valve Regurgitation

Backflow of blood due to incomplete valve closure.

Valve Stenosis

Narrowed valve opening restricting blood flow.

Valve Atresia

Congenital absence of a valve opening preventing blood passage.

Cardiomyopathy

Disease of heart muscle impairing function; includes dilated, hypertrophic, restrictive, and arrhythmogenic types.

Dilated Cardiomyopathy (DCM)

Condition where ventricles enlarge and weaken, reducing ejection of blood.

Hypertrophic Cardiomyopathy

Thickening of heart muscle that can obstruct blood flow and disrupt rhythm.

Restrictive Cardiomyopathy

Stiffening of ventricles limiting filling.

Arrhythmogenic Right Ventricular Cardiomyopathy

Replacement of right ventricular muscle with fibrous/fatty tissue causing rhythm disturbances.

Left Ventricular Assist Device (LVAD)

Mechanical pump aiding circulation in patients with severe heart failure.

Atrial Septal Defect (ASD)

Congenital hole in interatrial septum allowing blood mixing.

Ventricular Septal Defect (VSD)

Hole in interventricular septum causing oxygenated and deoxygenated blood to mix.

Patent Ductus Arteriosus (PDA)

Persistent fetal connection between aorta and pulmonary artery post-birth.

Tetralogy of Fallot

Set of four congenital defects including pulmonary stenosis and ventricular septal defect.

Systole

Phase of cardiac contraction ejecting blood from ventricles.

Diastole

Phase of cardiac relaxation allowing ventricular filling.

Systolic Blood Pressure

Pressure in arteries during ventricular contraction; clinical standard ≈120 mmHg.

Diastolic Blood Pressure

Pressure in arteries during ventricular relaxation; clinical standard ≈80 mmHg.

Hypertension

Persistently elevated arterial blood pressure; classified as primary or secondary.

Sinoatrial (SA) Node

Pacemaker cell cluster in right atrium generating spontaneous action potentials.

Cardiomyocytes

Heart muscle cells responsible for contraction upon electrical stimulation.

Intercalated Discs

Specialized connections between cardiomyocytes enabling synchronized contraction.

Depolarization

Loss of membrane potential difference as Na⁺ enters cell, initiating contraction.

Action Potential

Rapid electrical change across cell membrane propagating contraction signals.

Repolarization

Return of cell membrane to negative resting potential, leading to relaxation.

Plateau Phase

Sustained depolarization phase in cardiac action potential due to Ca²⁺ influx.

Atrioventricular (AV) Node

Node slowing conduction between atria and ventricles, located in right atrium base.

Bundle of His

Conductive fibers transmitting impulses from AV node to ventricular septum.

Bundle Branches

Right and left pathways conducting impulses down interventricular septum.

Purkinje Fibers

Terminal fibers distributing impulses to ventricular myocardium.

Electrocardiogram (ECG/EKG)

Recording of the heart's electrical activity via skin electrodes.

P Wave

ECG deflection representing atrial depolarization.

QRS Complex

ECG waveform indicating ventricular depolarization (and hidden atrial repolarization).

T Wave

ECG deflection representing ventricular repolarization.