A 78-Year-Old Man Is Brought to the Emergency Department Due

question 280

Multiple Choice

A 78-year-old man is brought to the emergency department due to lightheadedness that began earlier in the day.  This morning, the patient felt unsteady and almost passed out when he tried to get out of bed.  He has not had similar symptoms before and he has had no chest pain or shortness of breath.  He has a history of coronary artery disease requiring percutaneous coronary intervention.  The rhythm strip of the ECG obtained in the emergency department is shown in the exhibit. 
Which of the following is the most likely cause of this patient's current symptoms?

• A)Degenerative changes involving the atrioventricular node
• B)Degenerative changes involving the sinus node
• C)Ectopic electrical foci in left ventricular myocardium
• D)Reentrant circuit involving the cavotricuspid isthmus
• E)Sporadic depolarization of atrial cardiomyocytes

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Definitions:

Cultural Animal

A term that highlights the notion that humans are deeply influenced and shaped by their cultural environments and social learning.

Social Animal

A term used to describe humans or other creatures that are innately inclined to live in communities or groups.

Social Animals

Refers to species that are inclined to live in communities or groups, interacting with each other for various survival and social benefits.

Cultural Act

An action or behavior that is shaped by and contributes to the customs, beliefs, and traditions of a particular society or group.