USMLE Forum Archives - USMLE Step 2 CK - IM 9
IM 9
TheOne - 11-02-06 20:01
A 35-year-old woman comes to the emergency department complaining of chest pressure.
She has had such episodes intermittently over the last 5 years, usually when sleeping, but
over the last year she has had more frequent severe symptoms that are occasionally
associated with severe migraine headaches. The pain is midsternal and is described as
pressure that extends as a band around her chest. The emergency department physician is
initially dubious that the pain is cardiac in origin, because the woman has no coronary disease
risk factors. An electrocardiogram, however, shows 2-mm ST-segment deprsssion and inverted
T-waves in leads V1 through V5 and 1-mm ST-segment elevation in leads II, III, and aVF.
Before the cardiologist arrives in the emergency department, however, the patient's
electrocardiogram has returned to normal. This repeat normal electrocardiogram is obtained
after the administration of aspirin, nitroglycerin, morphine, and oxygen. Which of the following
is the most likely explanation for these findings?
A. Diffuse intimal thickening with focal areas of atherosclerotic narrowing
B. Intermittent thrombus formation and lysis in the left anterior descending artery
C. Intermittent thrombus formation and lysis in the right coronary artery
D. Plaque rupture and thrombus formation in the left anterior descending artery
E. Transiently increased coronary vascular tone in the right coronary artery
TheOne - 11-02-06 20:01
A 35-year-old woman comes to the emergency department complaining of chest pressure.
She has had such episodes intermittently over the last 5 years, usually when sleeping, but
over the last year she has had more frequent severe symptoms that are occasionally
associated with severe migraine headaches. The pain is midsternal and is described as
pressure that extends as a band around her chest. The emergency department physician is
initially dubious that the pain is cardiac in origin, because the woman has no coronary disease
risk factors. An electrocardiogram, however, shows 2-mm ST-segment deprsssion and inverted
T-waves in leads V1 through V5 and 1-mm ST-segment elevation in leads II, III, and aVF.
Before the cardiologist arrives in the emergency department, however, the patient's
electrocardiogram has returned to normal. This repeat normal electrocardiogram is obtained
after the administration of aspirin, nitroglycerin, morphine, and oxygen. Which of the following
is the most likely explanation for these findings?
A. Diffuse intimal thickening with focal areas of atherosclerotic narrowing
B. Intermittent thrombus formation and lysis in the left anterior descending artery
C. Intermittent thrombus formation and lysis in the right coronary artery
D. Plaque rupture and thrombus formation in the left anterior descending artery
E. Transiently increased coronary vascular tone in the right coronary artery
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#1
Re: IM 9 kingkong - 11-03-06 21:08 very good question.but don't know the answer kindly explain.is this case related to pneumothorax?i think it can be E sinnce the ecg returns to normal after nitroglycerin and oxygen administration, a clear case of myocardial ischemia due to coronary artery vasoconstriction.
#2
Re: IM 9 raafat - 11-06-06 07:10 :nuts: i think its e its vasospastic angina ? young age ,at rest , frequent, with migran
#3
Re: IM 9
TheOne - 11-06-06 12:37 Explanation: The correct answer is E. This patient has a classic presentation for variant angina, which is caused by coronary vasospasm that induces transient ischemia and ST-segment elevations. Vasospasm often is seen in the distribution of the right coronary artery, which can result in transient inferior ischemia. The ST-depressions in the anterior leads likely represent reciprocal changes rather than the primary pathology. Associated vascular phenomena, such as Raynaud phenomenon or migraines, are common clues to the diagnosis. ST-segment elevation that responds to nitroglycerin makes the diagnosis almost certain, because a transmural myocardial infarction, caused by plaque rupture and thrombus formation (choice D), does not have transient ST-segment elevations.
Diffuse intimal thickening and focal areas of atherosclerotic narrowing (choice A) may be seen in severe atherosclerotic disease and classic angina. Classic angina may present with ST-segment depressions but would not cause transiently increased ST-segment elevation.
Intermittent thrombus formation and lysis (choices B and C) is the pathophysiology underlying unstable angina. It is an extremely unlikely diagnosis in a young, healthy woman with no coronary risk factors. Variant angina, also known as Prinzmetal angina, is a more likely diagnosis.
#5
Re: IM 9 bingousmle - 07-21-10 01:04 Transiently increased coronary vascular tone in the right coronary artery is the most likely explanation for the EKG findings in the patient
#6
Re: IM 9 paperp - 10-22-10 12:58 II,III aVF is inferior wall which is supplied by the right coronary - therefore the answer can be limited to c or e
sounds like it would be e - coronary vasospasm/ prinzmetal angina because it is a young female without coronary artery disease risk factors
#7
Re: IM 9 babbu5508 - 10-22-10 15:04 E. Transiently increased coronary vascular tone in the right coronary artery.........vasospastic angina......................
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