Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
21 Cards in this Set
- Front
- Back
|
|
The first phase of the cardiac cycle is atrial systole. AV Valves open, Semilunar Valves closed Pressure from atria contraction pushes blood in AV valves and into ventricles Creates EDV |
|
|
f |
Isovolumetric Contraction All Valves are closed AV valve closing makes first heart sound As a result of systolic contraction, ventricular pressure increases |
|
|
|
Rapid ejection phase B/c of ventricular systolic pressure rose in phase 2 SL valves open blood ejected into aorta and pulmonary arteries |
|
|
|
Reduced ejection SL valve stays open AV valves stay closed Ventricles finish systole. Ejection from phases 3 & 4 is approx. 2/3 of the blood volume in the ventricles which is referred to as stroke volume. |
|
|
|
Isovolumetric Relaxation Stage SL Valves close Makes second heart sound Pressure in the arteries exceeds pressure in the ventricles. 1/3 of blood left in the ventricles which gives you the end-systolic volume |
|
|
|
Rapid ventricular Filling AV valves open b/c of pressure of venous blood Both atrias and ventricles fill with blood |
|
|
|
Reduced filling AV valves stay open Ventricles slowly continue to fill and the cardiac cycle is ready to start again |
|
|
|
Sino-atrial node SA node Primary Pacemaker |
|
|
|
Internodal tracts & Bachmann's bundle |
|
|
|
Atrio-ventricular Node Secondary pacemaker |
|
|
|
AV node delay Ensures atria have ejected all blood into ventricles before ventrical contraction |
|
|
|
AV bundles |
|
|
|
Right and left bundle branches |
|
|
|
Purkinje fibers which are the tertiary pacemaker |
|
|
|
ECG= Electrocardiogram Measures sum of multiplle action potentials in many cardiac myofibers |
|
|
|
P Wave Atrial depolarization Aligns with phase 1 |
|
|
|
QRS complex Ventricular depolarization Phase 2 |
|
|
|
T wave Ventricular Repolarization Phase 4 |
|
|
|
P-R Interval Atrial Depolarization, systole, and onset of ventricular depolarization |
|
|
|
S-T segment Ventricles depolarized & systole occurs |
|
|
|
Q-T interval represents ventricular depolarization & Repolarization |
