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Free STEP3 Exam Braindumps (page: 41)

Page 40 of 202
PDF with 804 Questions

A 70-year-old male is seen in the office for chest pain. He reports that he is getting substernal chest pain, without radiation, when he mows his lawn. The pain resolves with 1015 minutes of rest. He has never had pain at rest. He has no other cardiac complaints and his review of systems is otherwise negative. He has an unremarkable medical history and takes only a baby aspirin a day. On examination, his blood pressure is 160/70, pulse 85, and respiratory rate 16. His cardiac examination is notable for a harsh, 3/6 systolic ejection murmur along the sternal border that radiates to the carotid arteries. His carotid pulsation is noted to rise slowly and is small and sustained. His lungs are clear. The remainder of his examination is normal.

Subsequent workup confirms the diagnosis of critical aortic stenosis. Which of the following treatments would be most appropriate at this time?

  1. a beta-blocker
  2. an ACE inhibitor
  3. a long-acting nitrate with as-needed sublingual nitroglycerin
  4. balloon valvuloplasty
  5. aortic valve replacement

Answer(s): E

Explanation:

Aortic stenosis is one of the most common valvular abnormalities found in adults. It can be congenital -- such as a unicuspid or bicuspid valve--or acquired. In young adults, acquired aortic stenosis is often seen as a consequence of rheumatic fever. This is becoming less common in developed nations. In adults over the age of 65, the most common cause of aortic stenosis is age-related degenerative, calcific aortic stenosis. The valvular cusps are immobilized and the stenosis caused by calcium deposits along the flexion lines of the valves. Acquired aortic stenosis typically has a prolonged asymptomatic period. During this time the stenosis may be found incidentally by auscultation of the characteristic harsh, holosystolic murmur in the aortic valve area that radiates to the carotid arteries. There may also be a slow, small, and sustained arterial pulsation (pulsus parvus and tardus) due to the relative outflow obstruction. The cardinal symptoms of aortic stenosis that signal advancing disease, and increased risk of mortality, are angina, heart failure, and syncope. An ECG will show left ventricular hypertrophy in approximately 85% of symptomatic cases of aortic stenosis.

A normal ECG is possible but would be more likely in early, asymptomatic stages. S-T segment elevation would be more consistent with acute cardiac ischemia and Q waves would be more consistent with a completed MI. Low-voltage QRS complexes can be seen in several conditions, including pericardial effusion, COPD, or obesity. When considering the diagnosis of aortic stenosis, the initial diagnostic test of choice would be echocardiography. It would provide information on both the structure (bicuspid, tricuspid, and the like) and the function (valve area, pressures) of the valve. The size and function of the left ventricle can also be determined. If aortic stenosis is found on echocardiogram and the patient is symptomatic, the next test would be cardiac catheterization.

This would allow for direct measurement of the pressure gradient across the valve. It would also allow for evaluation of the status of the coronary arteries in order to determine whether CABG would need to be performed along with valve replacement. Exercise stress testing is relatively contraindicated in the setting of symptomatic aortic stenosis. Holter monitoring would only be useful if there were a concomitant arrhythmia. Electrophysiologic studies would not play a role in the typical evaluation of aortic stenosis.



A 42-year-old woman with hyperlipidemia, hypertension, and hypothyroidism presents to your office for a routine follow-up visit. Her blood pressure is well controlled with hydrochlorothiazide. She has been on a stable dose of levothyroxine for 8 years and measurement of her TSH today is within normal limits. However, her LDL cholesterol level remains elevated despite taking a statin for the past 9 months and complying with lifestyle modifications. You decide that the addition of a low dose of cholestyramine would provide her with additional benefit. How would you advise the patient before beginning this therapy?

  1. She should take other medications at least 1 hour before or 4 hours after cholestyramine.
  2. She should take a multivitamin tablet daily.
  3. She should ingest the cholestyramine in its dry form.
  4. She may mix the cholestyramine with water, juices, or carbonated beverages.
  5. She should discontinue the cholestyramine immediately if she experiences steatorrhea.

Answer(s): A

Explanation:

Cholestyramine is a bile acid sequestrant which binds bile acids and similar steroids in the intestine, thereby reducing concentrations of LDLs in the circulation. Orally administered drugs may also bind to cholestyramine, however, impairing their efficacy by impairing absorption in the gut. This problem can be alleviated by administering other oral medications at least 1 hour before or 4 hours after cholestyramine. Examples of compounds which may be bound by cholestyramine include warfarin, digoxin, glipizide, phenytoin, methyldopa, thiazide diuretics, niacin, and statins. Fat-soluble vitamins (A, D, E, and K) may also bind to cholestyramine. Cholestyramine powder should never be administered in its dry form due to the risk of aspiration. It should be combined with water, pureed- consistency food, or a noncarbonated beverage. Use of carbonated liquids as a solvent may exacerbate the common side effects of heartburn and indigestion. Fat-soluble vitamins (A, D, E, and K) may also bind to cholestyramine; if steatorrhea develops, with associated impairment of fatsoluble vitamins, vitamin supplementation is recommended.



A 64-year-old male has been suffering from lower back pain for over 10 years. You have been following him for this period. You have prescribed stretching exercises and, occasionally, an anti- inflammatory medication to alleviate his pain. Although he has had no neurologic deficits in the past, today he has shown up in your office unexpectedly, complaining of bilateral lower back pain with numbness and tingling over the dorsal aspect of both feet. His symptoms have become progressively worse over the past 2 weeks and he is now unable to stand for more than 5 minutes without developing extreme pain and numbness. His symptoms are much improved by sitting down or kneeling over a chair. Climbing stairs seems to be tolerated well, but walking greatly exacerbates the pain. He denies bladder or bowel incontinence or retention, point tenderness or anesthesia in the lower back along the spinal cord or in the saddle area.

What is the likely diagnosis?

  1. spondyloathropathy of the sacroiliac joint
  2. age-related early degenerative joint disease (DJD) of the hips
  3. spinal stenosis of the lumbosacral area
  4. muscle spasm of the lower back
  5. cauda equina syndrom

Answer(s): C

Explanation:

Although all of the given diagnoses could produce similar symptoms, there are distinct findings which suggest a diagnosis of spinal stenosis. Spinal stenosis is a degenerative disorder of the spine which normally presents after the age of 50. Neurologic symptoms, including dysesthesias and paraesthesias, and pain are often bilateral and not localized, since it commonly affects multiple vertebrae. The symptoms are improved with flexion of the spine (sitting or climbing stairs) and worsened by straightening the spine (standing). There is no localized pain in the sacrum and no bowel or bladder incontinence, so a diagnosis of cauda equina syndrome or spondyloarthopathy is less likely. Muscle spasms and early DJD should not produce such neurologic findings. The most sensitive and specific imaging study in the diagnosis of spinal stenosis, among those given above, is an MRI of the spine at the affected area. Although x-rays of the spine have been frequently used in the past in the evaluation of lower back pain, they have been shown to be of limited value in diagnosing pathology. Bone scans may detect malignancy or infection before radiography does, but are of no value in spinal stenosis. Indium scans would be useful in occult inflammatory pathology and nerve conduction studies would suggest a neuropathic deficit, but would not help in localizing the defect.



A 64-year-old male has been suffering from lower back pain for over 10 years. You have been following him for this period. You have prescribed stretching exercises and, occasionally, an anti- inflammatory medication to alleviate his pain. Although he has had no neurologic deficits in the past, today he has shown up in your office unexpectedly, complaining of bilateral lower back pain with numbness and tingling over the dorsal aspect of both feet. His symptoms have become progressively worse over the past 2 weeks and he is now unable to stand for more than 5 minutes without developing extreme pain and numbness. His symptoms are much improved by sitting down or kneeling over a chair. Climbing stairs seems to be tolerated well, but walking greatly exacerbates the pain. He denies bladder or bowel incontinence or retention, point tenderness or anesthesia in the lower back along the spinal cord or in the saddle area.

Which of the following imaging studies would be most helpful to confirm the diagnosis?

  1. an MRI of the lumbosacral spine
  2. an x-ray of the lumbosacral spine
  3. an indium-tagged WBC scan
  4. a bone scan of the sacrum
  5. nerve conduction study of the legs bilaterally

Answer(s): A

Explanation:

Although all of the given diagnoses could produce similar symptoms, there are distinct findings which suggest a diagnosis of spinal stenosis. Spinal stenosis is a degenerative disorder of the spine which normally presents after the age of 50. Neurologic symptoms, including dysesthesias and paraesthesias, and pain are often bilateral and not localized, since it commonly affects multiple vertebrae. The symptoms are improved with flexion of the spine (sitting or climbing stairs) and worsened by straightening the spine (standing). There is no localized pain in the sacrum and no bowel or bladder incontinence, so a diagnosis of cauda equina syndrome or spondyloarthopathy is less likely. Muscle spasms and early DJD should not produce such neurologic findings. The most sensitive and specific imaging study in the diagnosis of spinal stenosis, among those given above, is an MRI of the spine at the affected area. Although x-rays of the spine have been frequently used in the past in the evaluation of lower back pain, they have been shown to be of limited value in diagnosing pathology. Bone scans may detect malignancy or infection before radiography does, but are of no value in spinal stenosis. Indium scans would be useful in occult inflammatory pathology and nerve conduction studies would suggest a neuropathic deficit, but would not help in localizing the defect.






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