cardiology Flashcards
Atrial contraction squeezes last bit out into the ventricles, 10% of EDV
Atrial kick
What is S1 from?
Tricuspid and mitral valve closure during systole
What is S2 from?
Pulmonic and Aortic valves close during diastole
Division of the aortic root that supplies the septum and anterior ventricular wall (left coronary circulation)
Left Anterior Descending Artery
Division of the aortic root that supplies the left ventricular wall (left coronary circulation)
Left circumflex artery
Division of the aortic root hat supplies the right ventricle (right coronary circulation)
Marginal Branch
Division of the aortic root that supplies the posterior and inferior left ventricle (right coronary circulation)
Posterior descending
What % of people have a posterior descending artery from the RCA?
80%, right dominance
The ability of cardiac cells to independently and repeatedly depolarize
automaticity
How do you find CO?
CO = SV x HR
How do you find SV?
EDV - ESV = SV
Cardiac muscle stretch at the start of systole
Preload
Pressure that the ventricles contract against during systole (aortic pressure)
Afterload
What affects preload?
Blood volume Distribution of BV Atrial contraction Heart Rate Ventricular complicance (BDAHV)
T or F: Aortic pressure = ventricular pressure = Systolic BP
True
T or F: As BP rises, there is more SV
False. More resistance, less SV
What affects afterload?
Vascular resistance (systemic) Elasticity of the aorta Arterial blood volume Ventricular wall tension Aortic Valve stenosis
What could affect stroke volume on both preload and afterload curve?
Contractility
What affects contracility?
Calcium (intramyocardial) Ischemia/Necrosis Rate Fibrosis or ventricular compliance Ventricular remodeling
How do you find mean arterial pressure?
MAP = 1/3 systolic BP + 2/3 diastolic BP
What are the three layers of arteries and veins?
Intima
Media
Adventitia
Which structure has elastic tissue between intima and media?
Aorta
“vasa vasorum”
Myocardial contraction
Inotropy
Myocardial relaxation
Lusitropy
SA node firing
Chronotropy
AV node conduction velocity
Dromotropy
P wave on EKG
Atrial systole
How are mitral and tricuspid valves during atrial systole?
OPEN
What is S4 from?
Extra heart sound during atrial systole from forceful atrial contraction against a stiff ventricle
QRS on EKG
Isovolemic contraction
Ventricular pressure > atrial pressure
Ventricular contraction, aka Isovolemic contraction
How are mitral and tricuspid valves during isovolemic contraction?
Closed (S1)
Ventricular emptying. Ventricular pressure > Aortic pressure
Rapid ejection
ST segment and T wave on EKG
Rapid ejection
How are aortic and pulmonary valves during rapid ejection?
Open
Closure of the cycle, Aortic pressure > Ventricular pressure.
Isovolemic relaxation
What heart sound is associated with isovolemic relaxation?
Aortic and pulmonary valves closing (S2)
What is S3 from?
Extra heart sound in which you can hear rapid filling of ventricles
How are mitral and tricuspid valves during rapid filling?
OPEN
Peak pressure in the arteries near the end of systole
SBP
resting pressure in the arteries during diastole
DBP
Why worry about HTN?
It DOUBLES the risk of: CAD PAD CHF Stroke Renal failure
How does BP change over time?
SBP: men higher than women until 60, then women are higher
DBP: increase until 55, then decrease
If you’re over 60, there’s a _____% chance of having HTN
60
What are the signal pathways through which the ANS regulates BP?
Pressure
Volume
Chemoreceptors
Receptor Alpha 1: Location, effect?
Vascular smooth muscle
Vasoconstricts
Receptor Alpha 2: Location, effect?
neurotransmitter (epi or NE) synthesizing nerves
Inhibits NT release
Receptor Beta 1: Location, effect?
Cardiac cells
Increases rate and contractility
Receptor Beta 2: Location, effect?
Vascular smooth muscle
Vasodilation
Stretch or pressure sensor in aortic arch and carotids
Baroreceptors
With an increase in pressure, and therefore increased stretch, signals are released that cause what?
Decrease in sympathetic output
Decrease in HR and pressure
With a decrease in pressure and a decrease in stretch, signals are released that cause what?
Increase in sympathetic output
Increase in HR and Pressure
An alpha 1 antagonist would cause what?
lower BP
An alpha 1 agonist would cause what?
Higher BP
An alpha 2 antagonist would cause what?
higher BP
An alpha 2 agonist would cause what?
Lower BP
A beta 1 agonist would cause what?
higher BP
A beta 1 antagonist would cause what?
lower BP
A beta 2 antagonist would cause what?
higher BP
A beta 2 agonist would cause what?
lower BP
What effect does norepinephrine have at arteriole level?
Vasoconstricts
Main source of afterload
What will the kidneys release renin in response to?
Low BP
Low sodium
NE stimulation (Sympathetic signaling)