Mediastinum & Cardiovascular System Flashcards

Vocabulary practice flashcards covering anatomy, pathways, vessels, fetal shunts, lymphatic structures, and clinical conditions of the Mediastinum & Cardiovascular System.

Mediastinum

The median movable compartment of the thoracic cavity centrally located between the right and left pleural cavities that moves with respiration and is innervated by the phrenic nerve.

Superior Mediastinum

The top compartment of the mediastinum located superior to the heart that serves as a space for structures to pass between the head/neck and the thorax.

Anterior Mediastinum

The sub-compartment of the inferior mediastinum located in front of the heart between the heart and the sternum, comprising connective and fatty tissue that protects deeper structures.

Middle Mediastinum

The central sub-compartment of the inferior mediastinum that contains the heart, pericardium, and the roots of the great vessels.

Posterior Mediastinum

The sub-compartment of the inferior mediastinum located behind the heart that provides a passageway for structures passing through the thorax.

Prevascular Compartment

The section in front of the heart in the 3-part mediastinal classification system based on cross-sectional imaging (CT scans).

Visceral Compartment

The section containing the heart in the 3-part mediastinal classification system based on cross-sectional imaging (CT scans).

Paravertebral Compartment

The section behind the heart in the 3-part mediastinal classification system based on cross-sectional imaging (CT scans).

Pericardium

A protective, fluid-filled sac surrounding the heart and covering the roots of the great vessels, functioning to cushion, hold, lubricate, and protect the heart.

Great Vessels

The major blood vessels extending directly from the heart, including the aorta, main pulmonary artery, pulmonary veins, and superior and inferior vena cava.

Pericardial Cavity

The potential space between the visceral and parietal pericardial layers containing fluid that reduces friction as the heart beats.

Pericardiocentesis

A medical procedure using a needle and small catheter to remove excess fluid built up in the pericardial sac; also known as a pericardial tap.

Cardiac Conduction System

The network of specialized cells and nodes that generate and transmit electrical signals to enable the heart to beat.

Sinoatrial (SA) Node

The natural pacemaker of the heart located in the right atrium that creates the initial electrical excitation signal for each heartbeat.

Atrioventricular (AV) Node

The node in the cardiac conduction system that receives the excitation signal from the atria and delays it until the atria empty blood into the ventricles.

Bundle of His

The center bundle of nerve fibers in the cardiac conduction system that carries the electrical signal from the AV node to the Purkinje fibers.

Purkinje Fibers

The specialized conduction fibers that receive electrical signals from the Bundle of His and carry them to the ventricles, triggering ventricular contraction.

Circulatory System

The body system comprising both the cardiovascular system and the lymphatic system, responsible for transporting nutrients, gases, waste, maintaining body temperature, and defense.

Artery

A thick, muscular, elastic blood vessel with a narrow lumen that carries high-pressure, usually oxygen-rich blood away from the heart.

Vein

A thin, less muscular blood vessel with a wide lumen and valves that carries low-pressure, usually oxygen-poor blood toward the heart.

Pulmonary Circulation

The smaller, low-pressure circulatory circuit that carries deoxygenated blood from the right ventricle to the lungs for oxygenation and returns oxygenated blood to the left atrium.

Systemic Circulation

The larger, high-pressure circulatory circuit that pumps oxygenated blood from the left ventricle to the entire body tissues and returns deoxygenated blood to the right atrium.

Aorta

The body's largest artery, measuring about $2.5\,\text{cm}$ ($1\,\text{inch}$) in diameter, which receives oxygenated blood from the left ventricle and branches to supply the entire body.

Ascending Aorta

The initial portion of the aorta arising near the heart within the pericardial sac that gives off the left and right coronary arteries.

Aortic Arch

The section of the aorta that curves from right to left and posteriorly beyond the ascending aorta, giving off three major branches to the upper body.

Thoracic Aorta

The section of the descending aorta located anterior to the vertebral column and posterior to the heart in the chest cavity, supplying branches to the chest wall, esophagus, and bronchi.

Abdominal Aorta

The longest section of the descending aorta spanning the abdominal cavity, supplying visceral and parietal branches to abdominal organs and wall.

Descending Aorta

The continuous aortic section formed by the combination of the thoracic aorta and abdominal aorta.

Brachiocephalic Artery

An unpaired, short vessel branching from the aortic arch that extends upward under $5\,\text{cm}$ before dividing into the right subclavian and right common carotid arteries.

Right Subclavian Artery

A branch of the brachiocephalic artery extending under the right clavicle to supply blood to the right upper extremity (arm).

Right Common Carotid Artery

A branch of the brachiocephalic artery that travels upward to supply blood to the right side of the neck, head, and brain.

Left Common Carotid Artery

An artery arising directly from the highest part of the aortic arch that supplies blood to the left side of the neck and head.

Left Subclavian Artery

The last branch of the aortic arch, extending under the left clavicle to supply blood to the left upper extremity.

Intercostal Arteries

Usually $9$ to $10$ pairs of arteries arising from the thoracic aorta that extend between the ribs to supply muscles and structures of the chest wall.

Celiac Trunk

A short, unpaired visceral branch of the abdominal aorta (about $1.25\,\text{cm}$ long) that subdivides into the left gastric, splenic, and hepatic arteries.

Left Gastric Artery

A branch of the celiac trunk that carries blood to the stomach and adjacent portion of the esophagus.

Splenic Artery

A branch of the celiac trunk that supplies blood to the spleen, stomach, and pancreas.

Hepatic Artery

A branch of the celiac trunk that carries oxygenated blood to the liver, stomach, gallbladder, duodenum, and pancreas.

Superior Mesenteric Artery

The largest unpaired visceral branch of the abdominal aorta, supplying blood to most of the small intestine and the first half of the large intestine.

Inferior Mesenteric Artery

A small unpaired visceral branch of the abdominal aorta located near its lower end that supplies the second half (last third) of the large intestine.

Renal Arteries

The largest paired lateral branches of the abdominal aorta that carry oxygenated blood to the kidneys.

Suprarenal Arteries

Paired lateral branches of the abdominal aorta that supply blood to the adrenal (suprarenal) glands.

Phrenic Arteries

Paired branches of the abdominal aorta that supply blood to the diaphragm.

Common Iliac Arteries

The two terminal branches of the abdominal aorta, each about $5\,\text{cm}$ long, extending into the pelvis before dividing into internal and external iliac arteries.

Internal Iliac Artery

A terminal branch of the common iliac artery supplying the pelvic organs, including the urinary bladder, rectum, and reproductive organs.

External Iliac Artery

A branch of the common iliac artery that passes into the thigh, continuing as the femoral artery to supply the lower extremity.

Internal Carotid Artery

A branch of the common carotid artery that travels into the skull to supply the eye, anterior portion of the brain, and cranial structures.

External Carotid Artery

A branch of the common carotid artery supplying the thyroid gland, face, and other external head and upper neck structures.

Vertebral Artery

The first branch of the subclavian artery, passing through cervical transverse processes to supply the posterior brain.

Brachial Artery

The longest arterial segment in the arm proper, continuing from the axillary artery and subdividing near the elbow into radial and ulnar arteries.

Radial Artery

A branch of the brachial artery extending down the thumb side (lateral aspect) of the forearm and wrist.

Ulnar Artery

A branch of the brachial artery extending along the medial (little finger) side of the forearm into the hand.

Coronary Arteries

The left and right arteries arising from the base of the ascending aorta that encircle the heart to supply oxygen-rich blood to the myocardium.

Left Main Coronary Artery

A major coronary artery supplying the left atrium and left ventricle, dividing into the left anterior descending and left circumflex arteries.

Left Anterior Descending (LAD) Artery

A branch of the left coronary artery running in the anterior interventricular groove that supplies the front of the left ventricle and the septum.

Left Circumflex Artery

A branch of the left coronary artery that circles around the heart to supply blood to the outer side and back of the heart.

Right Coronary Artery

A major coronary artery supplying the right atrium, right ventricle, SA node, AV node, and septum via branches like the acute marginal artery.

Coronary Sinus

A large venous structure on the posterior aspect of the heart that collects venous blood from cardiac veins and empties directly into the right atrium.

Great Cardiac Vein

The largest tributary of the coronary sinus originating at the apex, ascending in the anterior interventricular groove, and curving left to form the coronary sinus.

Middle Cardiac Vein

A tributary of the coronary sinus originating at the heart's apex and ascending in the posterior interventricular groove.

Small Cardiac Vein

A tributary of the coronary sinus located on the anterior surface in a groove between the right atrium and right ventricle before emptying posteriorly.

Ductus Venosus

A fetal vascular shunt located at the liver that allows majority of oxygenated umbilical blood to bypass the liver directly into the inferior vena cava.

Foramen Ovale

An opening in the fetal interatrial septum that shunts oxygenated blood directly from the right atrium to the left atrium, bypassing the non-functional fetal lungs.

Ductus Arteriosus

A fetal vascular shunt connecting the pulmonary artery directly to the aorta, bypassing the fetal lungs.

Umbilical Vein

A blood vessel in the umbilical cord that carries oxygen-rich, nutrient-dense blood from the placenta to the fetus.

Umbilical Arteries

Two blood vessels in the umbilical cord that carry waste- and carbon dioxide-laden blood from the fetus back to the placenta.

Lymph Capillaries

Microscopic, blind-ended vessels weaving between tissue cells and blood capillaries that absorb leaked interstitial fluid.

Mini-valves

Overlapping flaplike edges of endothelial cells in lymph capillaries anchored by collagen fibers that open to permit interstitial fluid entry when pressure rises.

Right Lymphatic Duct

The lymphatic duct draining lymph from the right arm and right side of the head, neck, and thorax, emptying into the right subclavian vein.

Thoracic Duct

The main lymphatic vessel receiving lymph from the lower body, left upper body, and abdominal organs, emptying into the left subclavian vein.

Cisterna Chyli

A dilated sac posterior to the abdominal aorta (anterior to vertebrae L1 and L2) serving as the collection point for lower body lymph and origin of the thoracic duct.

Cardiomegaly

Abnormal enlargement of the heart resulting as a symptom of underlying conditions such as coronary heart disease, hypertension, or valve disease.

Myocardial Ischemia

Reduction of blood flow to the myocardium caused by partial or complete coronary artery obstruction, leading to cellular hypoxia.

Myocardial Infarction

Cessation of blood flow to a portion of the myocardium resulting in muscle tissue necrosis and cellular death; commonly called a heart attack.

Cardiac Tamponade

A life-threatening medical emergency caused by acute fluid accumulation in the pericardial sac that compresses the heart and reduces cardiac output.

Beck's Triad

The classic triad of clinical signs for acute pericardial tamponade, consisting of low blood pressure, distension of jugular veins, and muffled heart sounds.

Rheumatic Heart Disease (RHD)

Permanent damage to heart valves resulting from an immune-mediated inflammatory response following untreated Group A Streptococcus infection (rheumatic fever).

Coronary Artery Disease (CAD)

A condition where plaque/cholesterol deposits narrow coronary arteries, impairing blood, oxygen, and nutrient supply to the heart muscle.

Angina Pectoris

Chest pain or discomfort caused by transiently insufficient blood flow and oxygen supply to the myocardium.

Tetralogy of Fallot (TOF)

A congenital cyanotic heart defect consisting of four major features: Ventricular Septal Defect (VSD), Overriding Aorta, Pulmonary Stenosis (PS), and Right Ventricular Hypertrophy (RVH).