Flashcards in Cardiac cycle Deck (36)
what is the first event in the cardiac cycle?
is there isovolumic contraction during AV valve opening?
will there be isovolumic contraction with aortic regurgitation?
how is central venous pressure assessed?
right atrial pressure
what are three common causes of increased CVP?
tricuspid valve disorders
pulmonary arterial HTN
what two waves are most prominent on a jugular venous wave form? what do they correspond to?
X - fall in RA pressure after a wave peak
X' - descent of cardiac base, atrial relaxation
what is the dominant motion of the normal JVP?
X - X' descent
what do normal jugular venous pulsations provide information about?
right heart pressure
abnormal RA pressure
what is the cause of a very high A wave in jugular venous pulsations?
RA contracting against a closed RV
complete heart block
TV disorders (stenosis)
what is the cause of a CV wave in jugular venous pulsations?
ventricularization of RA pressure
TV regurgitation (CHV)
S1 corresponds to what?
closure of mitral and tricuspid valves
S2 corresponds to what?
aortic (A2) and pulmonic (P2) closure
varies with respiratory cycle
what is the cause of physiological splitting of S2?
increased venous return to RV
increased time to expel blood from RV
pulmonic valve stays open longer
when is widened splitting of S2 heard? why?
1. RBBB - delay in RV contraction - delay in pulmonic closure
2. pulmonic stenosis - more time to open - delay in closure
when does fixed splitting of S2 occur? why?
atrial septal defect
high capacitance, low resistance of pulmonary vasculature
delayed back pressure responsible for pulmonic valve closure
P2 is delayed
what are the causes of paradoxical splitting of S2? when does it occur, and why?
advanced aortic stenosis
expiration - abnormal delay in closure of aortic valve (A2 follows P2)
does timing of opening snap in mitral stenosis change with respiration?
what is the third heart sound S3?
1. early diastole following opening of AV valves during rapid ventricular filling
2. produced by tension of chordae tendinae during rapid filling
what is the fourth heart sound S4? when in the cardiac cycle is it heard?
produced when trying to fill a stiff ventricle - coincides with atrial contraction
presystolic (late diastole)
in which situations is S4 heard?
low compliance / hypertrophy / acute MI
where is an early diastolic murmur heard?
left sternal border
what type of murmur is heard at the left sternal border?
early diastolic murmur
where is a pansystolic murmur heard?
what types of murmurs are heard at the tricuspid area?
mid to late diastolic
what type of murmur is heard at the mitral area?
ejection type murmurs are due to what causes?
pansystolic type murmurs are due to what causes?
late systolic type murmurs are due to what cause?
mitral valve prolapse
aortic and pulmonic stenoses cause what type of murmur?