Cardiovascular System

What is the size and weight of the adult heart?

Size of a closed fist; 250g (females), 300g (males)

Where is the heart located in the thoracic cavity?

On the diaphragm, near the midline, in the mediastinum

What are the three layers of the heart wall?

Epicardium (visceral pericardium), myocardium (cardiac muscle), endocardium (simple squamous lining)

What forms the apex and base of the heart?

Apex: tip of left ventricle, rests on diaphragm
Base: posterior surface, mostly left atrium

How is the heart oriented in the chest?

In mediastinum, between sternum and vertebral column—allows chest compressions (CPR)

What is the function of the right heart?

Receives deoxygenated blood → lungs via pulmonary arteries

What is the function of the left heart?

Receives oxygenated blood → pumps to body via aorta

What are the two circulatory loops?

Pulmonary: right ventricle → lungs → left atrium
Systemic: left ventricle → body → right atrium

What blood do arteries usually carry? Exception?

Usually oxygenated; exception = pulmonary arteries

What blood do veins usually carry? Exception?

Usually deoxygenated; exception = pulmonary veins

What are the two pericardium layers and their components?

Fibrous: tough, collagen I, protects from overstretching
Serous: parietal (fused to fibrous), visceral (epicardium)

Function of pericardial cavity and fluid?

Reduces friction between pericardial layers

What are the four chambers of the heart?

Right atrium, right ventricle, left atrium, left ventricle

Function of atria vs. ventricles?

Atria: receive blood
Ventricles: pump blood

What separates the heart chambers?

Tricuspid (RA–RV), bicuspid/mitral (LA–LV)

What are interatrial and interventricular septa?

Interatrial: between atria
Interventricular: between ventricles

What do pulmonary arteries and veins do?

Pulmonary arteries: deoxygenated blood → lungs
Pulmonary veins: oxygenated blood → heart

What vessels drain into right atrium?

Superior and inferior vena cavae

What vessel sends blood from left ventricle to body?

Aorta

Name the four heart valves and locations.

Tricuspid (RA–RV), bicuspid (LA–LV), pulmonary (RV–pulmonary trunk), aortic (LV–aorta)

Function of AV vs. semilunar valves?

AV: prevent backflow into atria
Semilunar: prevent backflow into ventricles

What prevents atrial backflow?

Closure of AV valves during ventricular contraction

What are auricles?

Pouch-like structures that increase atrial capacity

What are the three sulci on the heart’s surface?

Coronary sulcus (atria–ventricle), anterior and posterior interventricular sulci (ventricle boundaries)

What supplies the myocardium with blood?

Right and left coronary arteries from ascending aorta

What drains the myocardium?

Cardiac veins → coronary sinus → right atrium

What does the coronary sinus do?

Collects cardiac venous blood, drains into RA

When do coronary arteries fill?

When heart relaxes (not during contraction)

What are arteries, veins, and capillaries structurally?

Arteries: thick walls, small lumen
Veins: thin walls, large lumen, valves
Capillaries: one-cell thick, exchange vessels

Compare arteries and veins.

Arteries: oxygenated, high pressure, thick wall, no valves, pulse
Veins: deoxygenated, low pressure, valves, large lumen, no pulse

Why do veins have valves?

Prevent backflow due to low pressure, esp. in legs

What is an anastomosis?

Union of arteries → collateral circulation

What is an end artery?

No anastomosis; blockage causes tissue death (e.g. retina)

What is the lymphatic system composed of?

Lymph, lymph vessels, nodes, organs (spleen, thymus, marrow)

3 functions of lymphatic system?

Drain excess fluid, immune response (lymphocytes), lipid transport

Where does lymph drain?

Into venous system at subclavian + internal jugular junctions

Right vs. Thoracic (left) lymphatic ducts drain what?

Right: right head, neck, thorax, upper limb
Thoracic: rest of body

What are the four parts of the aorta?

Ascending, arch, thoracic, abdominal

What arises from ascending aorta?

Right and left coronary arteries

What are the 3 branches of the aortic arch?

Brachiocephalic trunk → right subclavian & right carotid
Left carotid, left subclavian

What supplies brain: internal or external carotid?

Internal carotid → brain
External carotid → face, neck

What arteries form the Circle of Willis?

Internal carotid and vertebral arteries

Path of subclavian to hand arteries?

Subclavian → axillary → brachial → radial & ulnar → palmar arches → digital arteries

Where can you feel the brachial and radial pulses?

Brachial: anterior elbow, medial to biceps tendon
Radial: wrist, anterior distal radius

Where does descending thoracic aorta end?

T12 → through diaphragm

Branches of descending thoracic aorta (BIPE)?

Bronchial, Intercostal, Pericardial, Esophageal

Where does abdominal aorta start and end?

Starts: T12 (aortic hiatus)
Ends: L4 (bifurcates)

Single branches of abdominal aorta (CIS)?

Celiac (gastric, hepatic, splenic), Superior & Inferior mesenteric

Paired branches of abdominal aorta?

Renal, gonadal, lumbar, common iliac

At what level does aorta bifurcate?

L4

What does common iliac artery bifurcate into?

Internal iliac (pelvis), external iliac (→ femoral, supplies limb)

What are superficial vs. deep veins?

Superficial: under skin, no artery pair, thermoregulation
Deep: accompany arteries, inside deep fascia

How does blood go from superficial to deep veins in legs?

Via perforating veins → deep veins → iliac veins → IVC

What forms SVC and IVC?

SVC: right & left brachiocephalic veins
IVC: right & left common iliac veins at L5

Which superficial veins are in upper limbs?

Cephalic (lateral), basilic (medial), median cubital (venipuncture site), dorsal venous arch

Which superficial vein is in the lower limb?

Great saphenous: anterior to medial malleolus → femoral vein

What causes varicose veins?

Incompetence of valves in great saphenous vein

Trace blood from left ventricle to right atrium (right hand).

LV → ascending aorta → arch → brachiocephalic → right subclavian → axillary → brachial → radial/ulnar → palmar arch → capillaries
DEEP: palmar venous arch → radial/ulnar veins → axillary → subclavian → brachiocephalic → SVC → RA
SUPERFICIAL: dorsal venous arch → basilic (medial) → brachial; cephalic (lateral) → axillary