Lecture 4: Cardiac Cycle, Heart Sounds, Murmurs Flashcards
a Swan-Ganz catheter can be used to detect activity of what location?
right atria,
right ventricle,
pulmonary artery
Forward flow of blood in that vessel is blocked and the transducer detects the “pulmonary wedge pressure” which is a good indicator of pressure in the _________
left atria
part of cardiac cycle:
ventricular contraction and ejection of blood
systole
part of cardiac cycle: ventricular relaxation and filling with blood
diastole
the heart has a “normal” resting rate of ____ bpm
72
assuming a resting rate of 72 beats per minutes, one cycle takes ______ seconds
0.8
The wiggers diagram presents systole & diastole for which heart sides
LEFT sides heart chambers
What is a?
- atrial systole
- triggered by the P wave
- small pressure rise as the atrium squeezes blood intro ventricle
- tops off ventricle-already 90-95% of blood
b?
b-c?
-b: mitral valve closure (begining of ventricular systole)
b-c: isovolumetic contraction
- triggered by QRS complex
-Aortic valve is closed (end of ventricular systole)
- pressure rises rapidly(mitral valve closure _ ventricular depol)
- volume is constant
- aortic pressure ~ 80 mmHg
note that both mitral & aortic valves are closed
c?
c: opening of aortic valve
-ventricular pressure exceeds aortic pressure
-begins ejection phase
-ejection initially rapid
-aortic pressure rises
D?
peak/reduction in ejection rate
- ventricle approaches the end of contraction (T wave occurring)
- outward flow declines as kinetic energy of blood decreases
-ventricular and aortic pressures begin to fall**
e-f?
e-f: isovolumetric relaxation
- forward movement of blood reverses, closing aortic valve
- incisura (dichrotic notch) indicates** aortic valve closure (e)**
-ventricular pressure falls precipitously
- atrial pressure rises as venous inflow fills the atrium
- aortic pressure falls as ejected blood drains away from heart
f:
f) opening of mitral valve
i) begins rapid filling of ventricle from accumulated blood in atrium
ii) rapid filling followed by reduced filling from pulmonary veins.
what marks the begining/end of systole?
mitral valve closure is the begining
aortic valve closure is the ending
normal pressure ranges for
left ventricle
aorta
left atria
left ventricle: 0-120mmHg
aorta: 80-120mmHg
left atria: 6-10mmHg
label the atrial pressure waves
a – atrial systole
c – closure of mitral valve
v – atrial filling and emptying
The cardiac cycle: P-V loop
EDV:
ESV:
define stroke volume:
**(EDV): **atrial systole fills the ventricular to the end diastolic volume
** the volume stays constant during isovolumetric contraction, then decreases as blood is ejected into the aorta*
- at the end of ejection, the volume remaining in the ventricle is the end systolic volume (ESV)
* EDV - ESV = stroke volume
S1 heart sound:
mitral valve closure (and tricuspid) valves with the sudden rise in ventricular pressure causes turbulence of blood in ventricles
S2 heart sound
closure of aortic & pulmonic valves causes vibrations of blood in the high pressure vessels
heart sound heard from vibration of ventricular walls during atrial systole in some individuals (Tennessee):
S4
heart sound heard during rapid filling in some individuals- normal in children (Kentucky):
S3
Name the murmur:
regurgitant flow through incompetent
mitral or tricuspid valve would result in a:
ventricular septal defect
pansystolic murmur
Name the murmer:
regurgitant flow through incompetent aortic or pulmonic valve would result in a:
mitral or tricuspid stenosis would this murmur
distolic murmur
a patent ductus arteriosus defect would cause a:
continuous murmurs
Patent ductus arteriosus: pressure gradient between ______________ persists in both systole and diastole
aorta and pulmonary artery
what is ventricle septal defect?
abnormal shunting of blood from one vascular chamber toanother lower pressure chamber
Systole (ejection) murmur
aortic or pulmonic stenosis: partial obstruction of flow
where is the backup of flow in the LV at the aortic valve?
how about from LV into the left atria?
How about from aorta into left ventricle?
where is there backup at the mitral valve in the left atria?
aortic stenosis
mitral regurgitation
aortic regurgitation
mitral stenosis
pressure in both atria and ventricle is higher in which side of the heart?
LEFT
the duration of systole is about _____ of the cycle
the duration of diastole is about _____ of the cycle
systole: 1/3
diastole: 2/3
what is the SV at rest?
70 mL
EF (ejection fraction):
SV/EDV ~55%
what causes the sounds of S1 & S2
turbulent flow when valves close
The heart pumps its stroke volume in the time between ________
S1 and S2
Events that occur almost simultaneously with onset of systole:
- QRS complex
- S1
- c wave
- closure of mitral valve
- rise in ventricular pressure
Events that occur almost simultaneously with onset of diastole:
- S2
- closure of aortic valve
-incisura
-drop in ventricular pressure
systemic & pulmonary blood flow are equal although __________can vary from beat to beat
SV
T/F: volumes & pressures can change in exercise or disease
TRUEEEE
T/F:all valves are closed during ISOVOLUMETRIC CONTRACTION & RELAXATION?
TRUEEE
CARDIA CYCLE FOR THE RIGHT SIDE OF THE HEART
