doyoudig
Forum Guru
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A 75-year-old woman comes to the office complaining of a 2-day history of palpitations. This morning
her palpitations were accompanied by some lightheadedness and nausea. You have been treating her
for mitral stenosis and hypertension. The patient has no history of coronary artery disease or
arrhythmias, and her exercise stress test from 1 year ago was negative. On physical examination, her
pulse is irregular ranging from 110 to 140/min and her blood pressure is slightly lower than usual at
95/70 mm Hg. A mid-diastolic murmur is audible at the cardiac apex, and her jugular venous pressure
is estimated to be 8 cm H2O. An electrocardiogram demonstrates atrial fibrillation with rapid ventricular
response. You admit the patient to the hospital and she is given a 10 mg bolus of intravenous
metoprolol and her heart slows to 90/min. Another electrocardiogram still demonstrates atrial fibrillation
and her blood pressure is now 135/85 mm Hg. A heparin infusion is started. She is observed overnight
and ruled out for myocardial infarction. After discussing treatment options the patient opts to have
elective cardioversion of her atrial fibrillation. Before she can undergo this procedure, she
A. must have a coronary angiogram
B. must have a negative stress test
C. must have a transesophageal echocardiogram
D. needs digoxin loading for rate control
E. requires anticoagulation for 3 weeks
The answer to this question is E, but I don;t understand why it cannot C????
Can somone pls explain
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| Adam
Forum Senior
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It's because tha Af is chronic ( >48 hour ), and the patient has other risk factors ( HTN, Mitral stenosis ).. Clot formation is more likely to occur when AF persist more than 48-72 hour. When you do a cardioversion without anticoagulants, the clot will release into the circulation.. thus anticoagulants is important in such cases.
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| arlete
Intern in 2009!!!!!
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Agree with Adam.
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| crispix
Forum Newbie
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I agree with the posts above, and have one thing to add. TEE is important if you're doing immediate cardioversion because you want to make sure there's not clot in the left atrium that's going to release when you cardiovert. However, there's pretty good evidence that if you anticoagulate for 3-4 weeks prior to cardioversion, you don't need to do the TEE because any clot that was there earlier will have dissolved. So most clinicians don't bother with the TEE if they have the luxury of anticoagulation.
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| doyoudig
Forum Guru
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I understand that u do anticoagulation in chronic AFib, but i did not understand in which circunstances u would go for TEE 1st??
Meaning lets say we get a pt w/ Afib & we have controlled his rate n now wnat to do cardioversion, what makes you wanna pick anticoagulation over TEE??
When would TEE be more approriate, what situation, does it depend on a pt doing elective vs immediate cardioversion??
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| arlete
Intern in 2009!!!!!
Topics: 36
Posts: 2,607
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This is what I found in the Cleveland Clinic site:
"There are two approaches to the reduction of thromboembolic risk for patients being considered for cardioversion of AF of greater than 48 hours duration. The conventional approach is to administer warfarin to achieve an INR value between 2.0 and 3.0 for at least 3 to 4 weeks prior to electrical or pharmacologic cardioversion. The second approach is the transesophageal echocardiography (TEE)-guided method. In some cases, cardioversion cannot be postponed for 3 or 4 weeks; in other cases, the patient and/or clinician may prefer an expedited approach to achieving sinus rhythm. In such situations, once a therapeutic level of anticoagulation is achieved with either warfarin or IV heparin, a TEE may be performed to rule out the presence of an intracardiac thrombus. If no thrombus is seen, cardioversion may be performed."
In both cases, anticoagulation comes first.
For acute Afib (you are sure it is lasting less than 48 h), you can do TEE, if no thrombus, cardioversion without anticoagulation. For the patient in question, she already had 2 days of symptoms, then was observed overnight, so she had more than 48 h of arrhythmia.
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| doyoudig
Forum Guru
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thank you arlete!!
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| arlete
Intern in 2009!!!!!
Topics: 36
Posts: 2,607
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