Cardiology Flashcards
What is the avergae size of a female and male heart
- Female- 8 Oz
- Male- 10 Oz
Where is the heart located and its position
- 2/3 left of the midline
- Apex: Anterior, inferior, left
- Base: Posterior, superior, right
Describe the pericardium
- The mebrane around the heart
- confines the heart to location but allows contaction
- Has fibrous and serous double layers
Describe the difference between the fibrous and serous layers of the pericardium
- Fibrous protects, anchors and prevents overstretching
- Serous is between fibrous layers, fluid to reduce friction during contraction
Describethe epicardium
- Outer thin, serous layer
- Aka visceral layer of serous pericardium
Describe the myocardium
- Muscle
- Middle layer
- Bulk of the cardiac tissue
- Pump action of the heart
Describethe endocardium
- inner layer for chambers and valves
- continuous with endothelial lining of large blood vessels
Describe blood flow around the heart
Deoxygenated Blood Flow:
Superior & Inferior Vena Cava → Right Atrium
Right Atrium → Right Ventricle (via Tricuspid Valve)
Right Ventricle → Pulmonary Arteries (via Pulmonary Valve)
Pulmonary Arteries → Lungs (for oxygenation)
Oxygenated Blood Flow:
Lungs → Pulmonary Veins
Pulmonary Veins → Left Atrium
Left Atrium → Left Ventricle (via Mitral Valve)
Left Ventricle → Aorta (via Aortic Valve) → Body
💡 Key Function: The heart pumps deoxygenated blood to the lungs for oxygenation and then sends oxygen-rich blood to the body for circulation
What is coronary circulation?
- Supplies oxygen-rich blood to the heart muscle (myocardium) and removes waste products.
Describe the coronary arteries
- Left Coronary Artery (LCA) →
- Left Anterior Descending (LAD) Artery: Supplies the front of the left ventricle & septum.
- Circumflex Artery: Supplies the left atrium & side of the left ventricle.
- Right Coronary Artery (RCA) →
- Right Marginal Artery: Supplies the right ventricle.
- Posterior Descending Artery (PDA): Supplies the back of the heart.
Describe the venous drainage of the coronary arteries
- Great Cardiac Vein → Coronary Sinus → Right Atrium
- Middle & Small Cardiac Veins → Coronary Sinus → Right Atrium
💡 Key Role: The coronary arteries provide the heart with the oxygen it needs to function, while the veins return deoxygenated blood to the right atrium for recirculation. 🚀
Describe the branches of the coronary arteries
- Left anterior descending: Diagonal branches
- Left circumflex: Marginal branches
- Right coronary artery: Posterior descending branch
Describe the position of the coronary arteries
- LAD: Most of the septum, anterior
- LCx: Lateral, posterior
- RCA: Right ventricle, inferior portion septum, inferior left ventricle
What does the cardiac conduction system consist of?
- Sinoatrial node
- atrioventricular node
- bundle of his
- right and left bundle branches
- purkinje fibers
- This system ensures a coordinated heartbeat, with the atria contracting first, followed by the ventricles
Describe the SA node
- Located in the right atrium
- Initiates electrical impulses (~60-100 bpm)
- Spreads signal across atria → atrial contraction
Describe the AV node
- Located at the junction of atria & ventricles
- Delays signal slightly to allow ventricles to fill
Describe the AV bundle
- Located in the interventricular septum
- Carries impulse from AV node to ventricles
Describe the right and left bundle branches
- Travel down the septum
- Direct signals to right & left ventricles
Describe the purkinje fibers
- Spread throughout ventricular walls
- Triggers ventricular contraction
Describe the four phases of ventricle diastole
- isovolumic relaxation: ventricle repolarization, t-wave
- Rapid early filling: 80%
- Diastasis: minimal
- Atrial filling: 10-15%
