Unit 6 Flashcards
Cardiophysiology
What is the function of the right atrium?
Receives blood from systemic circulation
The right atrium plays a crucial role in the heart’s process of circulating blood.
What is the location of the mitral valve?
Between left atrium and left ventricle
The mitral valve ensures one-way blood flow from the left atrium to the left ventricle.
What is the function of the tricuspid valve?
Between right atrium and right ventricle
The tricuspid valve prevents backflow of blood into the right atrium during ventricular contraction.
What is the role of the SA node?
Pacemaker
The SA node initiates the electrical impulses that regulate heartbeats.
What is the function of the AV node?
Delays conduction to allow proper ventricular filling prior to contraction
This delay is crucial for effective heart function.
What does the Bundle of His do?
Transmits impulses from the AV node to the bundle branches
It is part of the heart’s conduction system.
What is the purpose of Purkinje fibers?
Rapidly conduct impulses to the ventricular myocardium
This conduction ensures coordinated contraction of the ventricles.
What does the P wave represent in an ECG?
Atrial depolarization
It is useful for diagnosing atrial fibrillation.
What does the T wave correspond to?
Ventricular repolarization
This reflects the recovery of the ventricles following depolarization.
What does the QRS complex indicate?
Ventricular depolarization
It represents the contraction of the ventricles.
What is the function of the right and left coronary arteries?
Supply blood to the heart
They are essential for delivering oxygen-rich blood to heart tissue.
What does the left anterior descending artery supply?
Blood to the left ventricle’s anterior wall
It is critical for the function of the left ventricle.
What is the function of the right marginal branch?
Supplies blood to right ventricle; filled by right main coronary artery
This branch is important for right ventricular health.
What does the circumflex artery supply?
Supplies blood to left side of heart; filled by left main coronary artery
It plays a key role in nourishing the left side of the heart.
How is cardiac output calculated?
Heart rate X stroke volume
Cardiac output measures the amount of blood the heart pumps per minute.
What is the average cardiac output for an adult at rest?
5 L/min
This is a typical value for a healthy adult.
What is stroke volume?
Amount of blood pumped out of the left ventricle with each heart beat
It is a key measure of heart function.
What is afterload?
Resistance the ventricles must overcome to eject blood
It affects the workload of the heart.
What is preload?
Degree of stretch on myocardial fibers before contraction
It influences the strength of the heart’s contraction.
What does the Frank-Starling mechanism state?
A higher preload leads to a more forceful contraction
This principle is fundamental to cardiac physiology.
What is ejection fraction?
How much blood the left ventricle pumps with each contraction
It is a crucial measure of heart efficiency.
What is the sequence of electrical conduction in the heart?
SA node –> AV node –> bundle of His –> bundle branches –> Purkinje fibers
This pathway is essential for coordinated heart contractions.
What defines systolic heart failure?
Ejection fraction < 40%
This indicates a significant reduction in heart pumping ability.
What are varicose veins?
Vein in which blood has pooled, leading to distended, tortuous and palpable vessels
They are often a sign of venous insufficiency.
What is stable angina?
Pain relieved by rest or nitroglycerin; lack of permanent myocardial damage
It indicates transient ischemia of the heart.
What is an MI?
Necrosis of myocardial tissue
Myocardial infarction is commonly known as a heart attack.
What is the primary function of the lymphatic system?
Pick up excess fluid and return it to the bloodstream
It plays a vital role in fluid balance and immune function.
thrombus
blood clot that remains in vessel
embolus
blood clot breaks free and travels through bloodstream
Tetralogy of Fallot
- ventricular septal defect
- pulmonary stenosis
- overriding aorta
- right ventricular hypertrophy
functions of pericardial sac
- shields heart from trauma, infection and inflmmation
- anchors heart in position, preventing excessive damage
isolated systolic hypertension
elevated SBP with normal DBP
Frank-Starling Law
- the relationship between the force of heart contraction and intial length of myocardial fibers
- muscle fiber length is determined by end diastolic volume
- an increase in end diastolic volume leads to stronger contraction and increased stroke volume
calculation for MAP
D + 1/3(S-D)
