, Case Study 7 Atrial Fibrillation and Oral Anticoagulation
Scenario
You are the nurse working in an anticoagulation clinic. One of your patients is K.N., who has a
long- standing history of an irregular heartbeat, known as atrial fibrillation or A-fib, for which he
takes the oral anticoagulant warfarin (Coumadin). Recently K.N. had his mitral heart valve
replaced with a mechanical valve.
1. How does atrial fibrillation differ from a normal heart rhythm?
Atrial fibrillation is characterized by a total disorganization of atrial electrical activity due to
multiple ectopic foci, resulting in the loss of effective atrial contraction. (Elsevier)
In other words, A-fib occurs due to irritable sites in the atria. These fire at a rate of 400-660
times per min. These rapid impulses cause the muscles of the atria to quiver aka fibrillate.
This results in ineffectual atrial contraction, decreased stroke volume, and ultimately a
decrease in cardiac output, and a loss of atrial kick. (ECG’s Made Easy 3rd edition,
MosbyJems)
This differs from a normal heart rhythm because a normal aka sinus rhythm is 60-100bpm
and has a regular rhythm. This means that normal electrical activity starts in the SA node and
then heads down the normal conduction path through the atria, AV junction, bundle branches,
and ventricles. . (ECG’s Made Easy 3rd edition, MosbyJems)
2. What is the purpose of the warfarin (Coumadin) in K.N.'s case
K.N. Health history: chronic A-fib, coumadin therapy, mitral heart valve replaced with
mechanical valve.
In the case of K.N., the purpose of coumadin is needed after rate control drugs such as
calcium channel blockers, b blockers, dronedarone, and digoxin fail. Coumadin is also used
if cardioversion does not convert atrial fibrillation to normal sinus rhythm. For long term
anticoagulation therapy warfarin is the drug of choice. This in turn means monitoring of INR
to insure therapeutic levels are being maintained.
Additionally, in mechanical heart valve replacement coumadin is the drug of choice to
percent blood clots. (Elsevier p. 766)
CASE STUDY PROGRESS
K.N. calls your anticoagulation clinic to report a nosebleed that is hard to stop. You ask him to
come into the office to check his coagulation levels. The laboratory technician draws a PT/INR
test.
Scenario
You are the nurse working in an anticoagulation clinic. One of your patients is K.N., who has a
long- standing history of an irregular heartbeat, known as atrial fibrillation or A-fib, for which he
takes the oral anticoagulant warfarin (Coumadin). Recently K.N. had his mitral heart valve
replaced with a mechanical valve.
1. How does atrial fibrillation differ from a normal heart rhythm?
Atrial fibrillation is characterized by a total disorganization of atrial electrical activity due to
multiple ectopic foci, resulting in the loss of effective atrial contraction. (Elsevier)
In other words, A-fib occurs due to irritable sites in the atria. These fire at a rate of 400-660
times per min. These rapid impulses cause the muscles of the atria to quiver aka fibrillate.
This results in ineffectual atrial contraction, decreased stroke volume, and ultimately a
decrease in cardiac output, and a loss of atrial kick. (ECG’s Made Easy 3rd edition,
MosbyJems)
This differs from a normal heart rhythm because a normal aka sinus rhythm is 60-100bpm
and has a regular rhythm. This means that normal electrical activity starts in the SA node and
then heads down the normal conduction path through the atria, AV junction, bundle branches,
and ventricles. . (ECG’s Made Easy 3rd edition, MosbyJems)
2. What is the purpose of the warfarin (Coumadin) in K.N.'s case
K.N. Health history: chronic A-fib, coumadin therapy, mitral heart valve replaced with
mechanical valve.
In the case of K.N., the purpose of coumadin is needed after rate control drugs such as
calcium channel blockers, b blockers, dronedarone, and digoxin fail. Coumadin is also used
if cardioversion does not convert atrial fibrillation to normal sinus rhythm. For long term
anticoagulation therapy warfarin is the drug of choice. This in turn means monitoring of INR
to insure therapeutic levels are being maintained.
Additionally, in mechanical heart valve replacement coumadin is the drug of choice to
percent blood clots. (Elsevier p. 766)
CASE STUDY PROGRESS
K.N. calls your anticoagulation clinic to report a nosebleed that is hard to stop. You ask him to
come into the office to check his coagulation levels. The laboratory technician draws a PT/INR
test.
