01/12/2025
✅ OUTSIDE OF THE 🫀HEART — OVERVIEW
🔰 What is the External Anatomy of the Heart?
◾ The outside (external) structure of the heart includes major blood vessels, coronary arteries, veins, and chambers visible from the surface.
◾ These structures supply oxygenated blood to the body and nourish the heart muscle itself.
◾ The external features give insight into how blood enters, exits, and circulates through the heart.
🔰 Major Regions Seen Externally
◾ Base of the heart (upper broad part carrying major vessels)
◾ Apex of the heart (lower pointed region leaning left)
◾ Coronary vessels (arteries + veins) that lie on the surface
◾ Auricles—small ear-shaped muscular extensions of atria
✅ MAJOR BLOOD VESSELS ON THE HEART
🔰 Aorta (Largest Artery of Body)
◾ Originates from the left ventricle.
◾ Carries oxygen-rich blood to the entire body.
◾ Has an arch giving rise to major branches.
🔰 Pulmonary Arteries
◾ Carry deoxygenated blood from the right ventricle to the lungs.
◾ Only arteries to carry deoxygenated blood.
🔰 Superior Vena Cava (SVC)
◾ Brings deoxygenated blood from the upper body to the right atrium.
◾ Receives blood from the head, neck, arms, and chest.
🔰 Inferior Vena Cava (IVC)
◾ Returns deoxygenated blood from the lower body to the right atrium.
◾ One of the largest veins in the body.
✅ EXTERNAL CHAMBERS & STRUCTURES
🔰 Auricles
◾ Small, ear-shaped muscular pouches attached to the atria.
◾ Increase the capacity of atria to receive more blood.
◾ Right and left auricles are located at the upper surface of the heart.
🔰 Apex of the Heart
◾ Lower pointed end formed mainly by the left ventricle.
◾ Points downward, forward, and to the left.
◾ Important site for checking apical pulse.
🔰 Base of the Heart
◾ Opposite the apex.
◾ Contains major vessels: aorta, pulmonary trunk, venae cavae.
◾ Located behind the sternum at approximately the level of T6–T9 vertebrae.
✅ CORONARY ARTERIES – HEART’S OWN BLOOD SUPPLY
🔰 Left Coronary Artery (LCA)
◾ Arises from the left aortic sinus.
◾ Supplies most of the left side of the heart.
🔰 Left Anterior Descending (LAD) Artery
◾ Runs along the front of the heart.
◾ Supplies the anterior wall of the left ventricle & interventricular septum.
◾ Often called the “widow-maker artery” due to high-risk blockages.
🔰 Circumflex Artery
◾ Winds around the left atrium.
◾ Supplies the lateral and posterior surfaces of the left ventricle.
🔰 Right Coronary Artery (RCA)
◾ Supplies the right atrium, right ventricle, and SA/AV nodes.
◾ Runs along the right surface of the heart.
✅ CORONARY VEINS & BLOOD RETURN
🔰 Great Cardiac Vein
◾ Drains the left atrium and both ventricles.
◾ Runs alongside the LAD artery, following a similar path.
🔰 Coronary Sinus
◾ Largest venous channel of the heart.
◾ Located on the posterior surface (in back).
◾ Collects blood from all major cardiac veins and empties into the right atrium.
🔰 Relationship Between Coronary Arteries & Veins
◾ Arteries and veins run parallel in shallow grooves.
◾ Arteries deliver oxygen-rich blood to myocardium.
◾ Veins remove deoxygenated blood and metabolic waste.See more..🫀🩺🧑🏻⚕️🖼️👇🏻❤️👍🏻
