Recurrent Syncope Is Being Evaluated in a 66-Year-Old Man

question 315

Multiple Choice

Recurrent syncope is being evaluated in a 66-year-old man. Over the last 6 months, he has experienced three episodes of dizziness and palpitations, followed by a brief loss of consciousness. He is not experiencing any chest pain or dyspnea. The patient has a history of high blood pressure and hyperlipidemia. There is no history of sudden death in the family. The initial evaluation reveals that the ECG and echocardiogram are normal. An electrophysiologic study of the heart is performed. During the study, an intravenous infusion of a medication is given, resulting in the responses shown below. Which of the following medications was most likely administered to this patient?

• A)Acetylcholine
• B)Adenosine
• C)Clonidine
• D)Esmolol
• E)Isoproterenol
• F)Norepinephrine
• G)Phenylephrine

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Definitions:

Macular Degeneration

A disease that deteriorates the central portion of the retina, leading to loss of central vision.

Intraocular Pressure

The fluid pressure inside the eye, crucial for maintaining the shape of the eye and proper functioning of the visual system.

Refractory Error

Visual impairments caused by the eye's inability to focus light directly on the retina, resulting in blurred vision.

Acute Central Vision

The component of vision that is responsible for sharp, detailed vision straight ahead, primarily used for activities like reading and driving.