Exam 3- Cardiac, diuretics, anticoagulants, thrombolytics Flashcards
(111 cards)
Flow of blood through the heart and
systemic v pulmonary circuit
inferior/sup vena cava R atria tricuspid valve R ventricle pulm semilunar valve pulm trunk pulm arteries lungs
reoxygenated blood into heart via pulm veins L atria mitral valve L ventricle aortic semi-lunar valve aorta ascending aorta body
pulmonary circuit- pulmonary arteries to veins (lungs)
systemic circuit- aorta-vena cava (body)
electrical stim pathway of heart
top to bottom
SA node, AV, apex, Purkinje fibers, ventricles (contraction starts at bottom)
primary pacemaker of heart- signal from atria to ventricles
stimulated by bradycardia (sympathetic ns) function- depolarize sinoatrial node (in uppr prt right atrium)
transfer signal via AV
beta 2 v beta 1 receptors
beta 1- stimulate AV node= inc heart contractility
can contribute to vent remodeling w/ pt that have heart failure
beta 2- stimulate sympth nervous system= bronchodilation
L v R sided heart failure
L- blood backs into pulm system, hypertrophy/ overstretched L ventricle= dec SV= dec CO
“congestive heart faliure” s/s hypoxia and trouble breathing
R- blood backs into venous system= inc p pulm arteries= pulm edema, jugular venous distention, ascites
alpha 1 receptors
cause vasoconstriction and sm musc contraction
s/s heart failure
dec cardiac output= fatigue, exercise intol
FVO- crackles (L HR), pulm edema, inc rr, SOB, distress dec o2
(R HR)- distended jugular veins, periph edema
systolic v diastolic HF (b/ left sided)
systolic- dec contractility- hF w/ reduced ejection fraction
diastolic- shortened filling/relaxation time- HF w/ preserved ejection fraction
classification of HF- AHA stage v NYHA functional
aha- structural- A-D *need to know ejection fraction to test structural changes
A= high fisk but no structural changes of s/s
B-=structural changes, no s/s
C= structural changes w/ prior or current s/s
D= changes and s/s at rest- need specialized interventions
functional- s/s I-IV (based on pt ability to function, and complete ADL) I-asympt II-symptom w/ mod exertion III- sympt w/ minimal exertion IV- symtom at rest
heart failure def + causes
dec tissue perfusion
abnormal heart function
cause- CAD, HTN
cardiac output
hr x stroke vol min/mL amnt blood pumped/min normal 3-7 L/min dec heart rate or sv= dec co
stroke vol
mL/contraction x # beats/min
dec sv=dec co
contractility
(inotropy) strength of muscular contraction of the heart
dec contractility = dec co
inc contractility= inc sv=inc co *till a certain point (if too stretch myosin fibers have no leverage)
preload- def and causes of inc/dec
amnt stretching of ventricular cardiac musc before a contraction begins
dependant on vol fluid in ven
heart failure= inc preload
inc vol= inc preload= inc contractility (until certain point)
dec vol= dec preload= dec stroke vol= dec contractility= dec co
ideal is btw 8-12
causes dec= hemorr shock, dehydration= dec contact btw actin and myosin fibers (too srunched)
inc= fluid overload= dec contact of fibers
ejection fraction
percent of blood in LV leaving w/ e/ contraction
dec contractility= dec EJ
afterload
resistance against which LV has to work to push blood into arteries
factors- SVR (p in arteries) can inc w/ vasoconstriction
inc svr= inc afterload (P)
inc svr + additional V fluid from heart failure (preload) w small valve opening = inc p/workload= L ventricular remodeling
purpose of measuring bp
tells us lvl resistance
diastolic- resting state
systolic= CO
MAP= afterload
pathway of hf
dec EF- dec contractility- dec CO- inc sympathetic activation- stimulation of beta 1 recep. (vasoconstriction, fluid retention)- inc hr and contractility- alpha 1 recep activation (inc pvr and inc afterload P)- inc myocardial workload- dec co- dec renal perfusion- inc renin secretion- inc angiotensin 1- angiotensin 2 (vasoconstriction, fluid retention and inc bp) *also cardiotoxic at high lvls can cause v remodeling
fluid retention bc- inc aldosterone (na and h2o retention- further inc preload- L HF-pulm edema and R HF- peripheral edema)
natrietic peptides
stimulated by hypertrophy LV
anp/bnp- natural diuretic/vasodil
goals of pharmacologic therapy in hf
improve QOL and dec mortality/morbidity
by inc contractility
dec afterload, elevations in preload, ventricular remodeling, peripheral (R) and pulm edema (L)
classes meds to trt hf
ace inhib angiotensin recep neprilisyn inhib (ARNI) cardiac glycosides diuretics beta blockers
ace inhib- types, action and indications
lisinopril, enalapril, captopril, benazepril
action- dec conversion from ang 1 to ang2= dec preload and afterload
indications- hf, htn, dec mortality and morbidity after MI, prevn diab nephropathy (dec p and therefore damage of glomerular basement mem)
need to take if EF < 50% or s/s HF bc can dec prel, afterload and vent remodeling while improving EF
ace inhib- containdications, pharmacokin
coindiated- preg/lactation, hypersen (angioedema), renal impairment
pharmacokin- Po, duration 24h, 100% renal elimination
ace inhib- ae
hypotension (dec ang2= dec ability vasoconstrict)
watch after 1st dose! and espec if FVD (dehydration)
persistant dry cough- if block converting enzyme= inc bradykinin= inc dry cough
angioedema- inc risk as inc bradykinin (swelling of throat, feeling fullness, something stuck in throat)
hyperkalemia- flip btw na and K, dec ang 2= dec aldosterone= dec fluid retention= inc K 3.5-5 can result in vent tachy- cardiac dysrhyth