August 03, 2010

Assessment and Treatment of Chest Pain

Patients who present to the doctor's office with chest pain are a diagnostic challenge given the wide array of possible etiologies, including a potentially life-threatening condition. Studies have estimated that approximately one-third to one-half of these patients have musculoskeletal chest pain, 10 to 20 percent have gastrointestinal causes, 10 percent have stable angina, 5 percent have respiratory conditions, and approximately 2 to 4 percent have acute myocardial ischemia (including myocardial infarction).

This article is for Medical Students & Professionals
This is a Question & Answer revision article designed for medical students and professionals preparing for the PLAB, MRCP or USMLE examinations. They are based on actual questions from these examinations. You may find the Cardiovascular Disease article more useful, or one of our many articles on Diseases & Conditions, Medical Syndromes, Health & Wellness or Home Remedies.
In this article:
Initial assessment of chest pain
MCQ exam: clinical scenario
MCQ exam: answer
MCQ exam: explanation

Initial assessment of chest pain

The initial assessment of patients presenting with chest pain in your office should serve to identify patients with life-threatening conditions who need to be transferred to the emergency department. The evaluation should then proceed to a thorough history and physical examination which are used to assess the probability of various causes of chest pain and determine the need for further testing.

Initial triage at the minimum:
  • All patients should have vital sign and oxygen saturation measurement.
  • Patients with unstable vital signs should be evaluated urgently by a clinician.
  • If symptoms are concerning for aortic dissection (acute chest and back pain that is severe, sharp, with a ripping or tearing quality), blood pressure should be obtained in both arms.
  • If pericarditis is suspected, based on pleuritic chest pain and relief when sitting forward, pulsus paradoxus should be evaluated.
Patients who have unstable vital signs or symptoms of life-threatening conditions should be sent to the emergency department by ambulance.

An electrocardiogram (ECG) should be obtained for all patients with new-onset chest pain or pain that is different than previous episodes, even if associated with an established noncardiac etiology, unless there is an obvious cause for the pain (eg, pneumonia or suspected pneumothorax) and/or the patient is low risk for cardiovascular disease.

MCQ exam: clinical scenario

Mike comes into the office complaining of pain in his chest that comes and goes when he is emotionally distressed. Mike is 55 years old with an intracranial tumor. Further review of the ECG reveals a 2nd degree heart block.

What is the best treatment for this patient:

a) Nitroglycerin
b) Propranolol
c) Nifedipine
d) Verapamil
e) None of the above

MCQ questions & answers on medicalnotes.info

MCQ exam: answer

The correct answer is C.
The right choice is Nifedipine.

MCQ exam: explanation

Mike has a list of problems. First he has an intracranial tumor. Second, he is complaining of chest pains that occurs when emotionally disturbed. This is a typical sign of variant angina, also known as prizemetal angina. He also has a 2nd degree heart block. Therefore, the list of the problems that Mike has are as follows: 1. Variant angina; 2. Intracranial tumor; 3. 2nd degree heart block.

When dealing with angina we have to understand the cause of the underlying problem. Basically, angina is pain in the chest which is referred pain from the heart. It is a result of decrease in oxygen supply to the heart. In exertional angina, the heart is putting in a lot of work and it requires more oxygen than what it's supplied with. When looking at the coronary arteries, one will find atherosclerotic plaques covering the intima of these vessels. In variant angina, the coronary vessels are spastic. The spasticity is triggered by an emotional stress. Atherosclerosis is not directly related to variant angina.

To treat each of these two problems we have two different approaches. To treat variant angina we have to relax the coronary vessels. We can use nitroglycerin, but it would be of no good to Mike. Mike has an intracranial tumor. Nitroglycerin increases intracranial pressure, thus making Mike's life more miserable. We can also use Beta blockers or verapamil, a calcium channel blocker. This is not true in Mike's situation because he has a 2nd degree heart block. Both will aggravate it. We can use nifedipine. This is because it has an action on calcium channels of arteries more than on the heart. It has negligible effect on the heart. So it vasodilates Mike's coronary vessels without aggravating any of his existing problems.

Therefore, the correct answer is choice C.

Reference(s)
1). UpToDate: Outpatient evaluation of the adult with chest pain. Available online: https://www.uptodate.com/contents/outpatient-evaluation-of-the-adult-with-chest-pain

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