Chest Pain and Cardiac
Dysrhythmias
Answers
1.The answer is b.(Rosen, pp 1039-1044.)The patient’s presentation is
classic for an ACS. He has multiple risk factorswith T-wave abnormalities on
his ECG. The most appropriate initial management includes placing the
patient on a cardiac monitorto detect dysrhythmias, establish intravenous
access, provide supplemental oxygen,and administer aspirin.If the patient is
having active chest pain in the ED, sublingual nitroglycerinormorphine
should be administered until the pain resolves. This decreases wall tension and
myocardial oxygen demand. A common mnemonic used is MONA(Morphine,
Oxygen,Nitroglycerin, Aspirin) greets chest pain patients at the door.
(a)Although nitroglycerin is one of the early agents used in ACS, it is
prudent to first rule out a right ventricular infarct, which if present, may
lead to hypotension. (c)PCI is warranted if the patient’s ECG showed ST-
segment elevation. (d)The patient will require a chest x-ray and most
likely receive clopidogrel and heparin; however this is done only after
being on a monitor with oxygen and chewing an aspirin. (e)β-Blockers are
usually added for tachycardia, hypertension, and persistent pain and only
given once the patient is evaluated for contraindications. Relative con-
traindications to the use of β-blockers include asthma or chronic obstruc-
tive lung disease, CHF, and third-trimester pregnancy.
2.The answer is e.(Feied, 2006.)The patient most likely has a pulmonary
thromboembolism (PE)that embolized from a thrombus in her left calf.
The diagnosis of PE is usually made with a CT angiogram, echocardiogram,
or a ventilation-perfusion scan. The most common ECG abnormalities in
the setting of PE are tachycardia and nonspecific ST-T– wave abnormal-
ities.Any other ECG abnormality may appear with equal likelihood, but
none are sensitive or specific for PE. If ECG abnormalities are present, they
may be suggestive of PE, but the absence of ECG abnormalities has no sig-
nificant predictive value. Moreover, 25% of patients with proven PE have
ECGs that are unchanged from their baseline state.
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