A 62-year-old woman is brought to the emergency department because of acute chest pain. She also complains of diaphoresis, nausea, and lightheadedness. Her blood pressure is 90/60 mm Hg and pulse is 42/min. An ECG reveals ST-segment elevation in the inferior leads. The appropriate therapy is initiated, including a medication to treat her bradycardia. After initial treatment, her blood pressure is 120/70 mm Hg and pulse is 76/min. However, she now complains of severe right-sided eye pain. Which of the following is the most likely cause for this patient's eye pain?

Question

A 62-year-old woman is brought to the emergency department because of acute chest pain.  She also complains of diaphoresis, nausea, and lightheadedness.  Her blood pressure is 90/60 mm Hg and pulse is 42/min.  An ECG reveals ST-segment elevation in the inferior leads.  The appropriate therapy is initiated, including a medication to treat her bradycardia.  After initial treatment, her blood pressure is 120/70 mm Hg and pulse is 76/min.  However, she now complains of severe right-sided eye pain.  Which of the following is the most likely cause for this patient's eye pain?

Quizplus · Accepted Answer

ST-segment elevation in the inferior leads is diagnostic of an inferior myocardial infarction (MI). Inferior MIs are often due to blockage of the right coronary artery, the artery usually responsible for sinoatrial (SA) and atrioventricular (AV) node perfusion. Thus, inferior MIs are often associated with bradycardia. Atropine blocks vagal influence on the SA and AV nodes and is effective in increasing heart rate in such patients. Atropine's side effects are due to muscarinic receptor blockade in other organs. In the eye, atropine causes mydriasis, resulting in narrowing of the anterior chamber angle and diminished outflow of aqueous humor. This can precipitate angle-closure glaucoma in patients with shallow anterior chambers or higher than normal intraocular pressures. Acute closed-angle glaucoma presents with unilateral severe eye pain and visual disturbances (eg, halos). Individuals of Inuit and Asian descent are at increased risk of angle-closure glaucoma. The clinical indications for anticholinergic medications are summarized in the table. 11ec160b_3c22_3a18_9249_492d6e1fb7da_MD0001_00 (Choice A) Anticholinergic medications (cycloplegics) reduce pain and prevent the formation of adhesions in iridocyclitis (uveitis). Atropine does not precipitate iridocyclitis. (Choices B, E, F, G, and H) These conditions present with either loss of vision or visual disturbances. They are usually not painful and would not be affected by anticholinergic drugs. Educational objective: Atropine is indicated for the treatment of bradycardia as it decreases vagal influence on the SA and AV nodes. A common side effect is increased intraocular pressure. It may precipitate acute closed-angle glaucoma in susceptible individuals.

A 62-Year-Old Woman Is Brought to the Emergency Department Because