21- Arial Fibrillation Flashcards
t or f: atrial fibrillation is a greater burden on female population
true
but a greater % of men are affected
what does D-dimer indicaate?
active indicatior of clot formationa nd clot lyssi
describe a CHADS2 score
C- CHF H - HTN A- age greater than 75 D- diabetes S- secondary pt with prior ischemic strok of TIA
score indicates risk of stroke (thromboembolic risk)
increasing score indicates a decreasing NNT
describe NNT
number needed to treat to prevent one stroke per year with X drug
classify: atrial fibrillation episodes which last 1-7 days and may be recurrent
paroxysmal AF
classify: AF that is not self-limited and lasts for longer than 7 days
persistent AF
if over a year it is call long standing persistent AF
AF in a youn, glow risk, CHADS 2-0
lone AF
5 pathophysiologies of atrial fibrillation
- atrial enlargement
- ischemia
- toxins
- metabolic disease
- hemodynamic impairment (loss of atrial addition to SV or tachyarrhythmia)
irregularly irregular pulse –>
a. fib
variable intensity S1 –> a fib. why?
because varying stroke volume with the different contractions and therefore filling time
what is a crucial diagnostic tool for a. fib?
echocardiography
can reveal valvular disease, chamber enlargement or intracardiac thrombi
most common thromboembolism
nonvalvular afib
~50%
is the risk of stoke increased or decreased with lone afib?
decreased. it is low ~1%
4 consequences of a. fib
- thromboembolism
- diminished CO
- ischemic events
- exercise capacity diminution
non-valvular causes of a. fib
- age > 65
- HTN
- rheumatic heart disease
- prior stroke of TIA
- DM
- CHF
treatment goals of a. fib
rhythm and rate control
goal of rhythm control
restore/ maintain sinus rhythm
goal of rate control
maintain acceptable ventricualr rate in chronic A. fib
which is better: rate or rhythm control
?
no survival advantage with either strategy
rhythm control have more adverse drug problems
what is the primary choice for rhythm control
DC conversion. pharmacologic tx is less succesful and a secondary choice
goal HR for rate control of a. fib
80-100 bpm
common agents for acute rate control
beta blockers (metoprolol) and Ca2+ channel blockers (verapamil or ditiazem)
when are antithrombotics not indicated?
if udner 60 yo or a lone A. fib
what does NOAC stand for?
novel oral anticoagulant
limitations for use of NOAC
cost
rapid onset and offset
no reversal agent
what is the drop in stroke volume post a. fib
30%
