Aorta & Coronary Circulation Quiz

Aorta & Coronary Circulation

• Oxygenated blood is pumped from the left ventricle (LV) through the aortic valve (AoV) into the aorta (Ao).
• The aorta delivers oxygenated blood to the heart, head, and body.
• Normal aortic pressure is less than 120/80 mmHg.
• Normal aortic oxygen saturation is 98%.

Aorta Segments

• Aortic Root (AoR): houses the aortic valve (AoV) and the area from the AoV to the sinotubular junction (STJ).
• Ascending Aorta (AAo): begins superior to the aortic root and ends proximal to the aortic arch.
• Transverse or Aortic Arch (Ao Arch): origin of three large arteries that travel to the head and arms.
• Brachiocephalic Artery/Trunk: the first of three branches that originates from the aortic arch.
• Left Common Carotid Artery: the second of three branches that originates from the aortic arch.
• Left Subclavian Artery: third of three branches that originates from the aortic arch.
• Thoracic Descending Aorta (DAO): begins after the aortic arch, travels inferiorly within the chest cavity, and is superior to the diaphragm.
• Abdominal Descending Aorta: begins after the aorta passes inferior to the diaphragm, within the abdominal cavity, and has numerous branches to nourish various organs.

Aortic Arch Branches

• The aortic arch branches into the brachiocephalic artery, left common carotid artery, and left subclavian artery.
• The brachiocephalic artery immediately branches into the right common carotid artery and right subclavian artery.

Aortic Isthmus

• Prone to dissection/tear, especially from deceleration injuries.
• Between the left subclavian artery and ligamentum arteriosum.

Aortic Branches

• Arteries divide into arterioles and into capillaries.
• Capillaries are where exchange of nutrients and oxygen occurs within tissues.
• Venules excrete carbon dioxide and waste.
• Venules join into veins.

Coronary Arteries

• Coronary arteries feed the myocardium via a dense capillary network on the outside of the heart.

• Each coronary artery is responsible for supplying a specific portion of the myocardium with oxygenated blood.

• Ischemia: lack of oxygen, partial blockage of the arteries.

• Infarction: necrosis of tissue, total blockage.

• Myocardial Infarction (MI) = heart attack.

• Typical coronary arteries originate at the sinuses of Valsalva and travel down the outside of the heart muscle

• Two primary coronary arteries: left and right.

• Left Coronary Artery (LCA)

• Left Anterior Descending Artery (LAD)

• Left Circumflex Artery (LCX).

• Right Coronary Artery (RCA)

• Acute Marginal Artery (AMA)

• Posterior Descending Artery (PDA).

Coronary Dominance

• Right Dominant: RCA gives rise to the PDA.
• Left Dominant: LCA/LCX gives rise to the PDA.
• Co-Dominant: RCA and LCA/LCX both give rise to the PDA.

Cardiac Venous System

• Responsible for returning blood from the coronary artery system to the right atrium (RA).
• Great Cardiac Vein
• Middle Cardiac Vein
• Left Cardiac Veins
• Right Coronary Vein
• Anterior Cardiac Veins
• Thebesian Veins

Coronary Sinus

• Positioned along the posterior atrioventricular groove, behind the left atrium
• Receives blood from cardiac veins, emptying into RA
• Approximately 2.5 cm in length.
• Lowest O2 sat in the body (60%).

Parasternal Long/Short Wall Segments

• Segment identification is based on ultrasound imaging.
• Segments are described using terms like anteroseptal, posterolateral, inferolateral.
• Short axis ultrasound view (PSAX).

Test your knowledge on the aorta and coronary circulation. This quiz covers the structure, segments, and functions of the aorta, including key facts about blood pressure and oxygen saturation. Dive into the details of aortic anatomy and its significance in the cardiovascular system.