Hemodynamics (Part 1) Flashcards
What does the P wave represent?
Artial depolarization
What does P-R interval represent?
Beginning of P wave to beginning of QRS
What does the ST segment represents?
Represents the period when the ventricles remain depolarized
What does the T wave represent?
Represents ventricular repolarization
What is the flow of Cardiac Conduction?
SA node–> AV node–> Bundle of His–> Bundle branch (LBB & RBB)–> Purkinje fibers
What is the conduction pathway (bpm) of the cardiac system?
SA (60-100 bpm)
AV (40-60 bpm)
Ventricle (20-40 bpm)
What does the ECG show?
Electrical activity of the heart (recorded by skin electrodes)
What happens during diastole?
ventricles empty and relax
Tricuspid and mitral valves open
Blood leaves the atria and fills the ventricles
What happens during systole?
Ventricles contract
Increasing BP in ventricles forces (mitral tricuspid) valves closes
Pulmonic & Aortic valves open
Blood is ejected from ventricles into pulmonary artery and aorta
How long is the cardiac cycle?
Ventricular contraction (systole)— 1/3 of the cycle
Ventricular relaxation (diastole)— 2/3 of the cycle
What effect does rapid HR have on filling time?
Ventricles fill during diastole
The ventricles doesn’t fill as much and doesn’t eject as much blood so diastolic time shortens
What process happens first, Electrical or mechanical?
The electrical occurs first then mechanical
What does the arteries do?
Carries blood AWAY from the heart
What does veins do?
Carries blood towards the heart
How many layers does the heart have?
3-Epicardium, myocardium, endocardium