A 65-Year-Old Man Is Brought to the Emergency Department After

question 778

Multiple Choice

A 65-year-old man is brought to the emergency department after a syncopal episode.  He was sitting at the kitchen table when his wife saw him suddenly slump over.  She estimates he was unresponsive for 30 seconds.  He felt "completely fine" after the incident and was not confused.  The patient sustained no trauma and does not remember any symptoms prior to the event.  He has a history of benign prostate hyperplasia, hypertension, and a myocardial infarction requiring stent placement 3 years ago.  He takes aspirin, carvedilol, atorvastatin, ramipril, and tamsulosin.  Temperature is 36.7 C (98 F) , blood pressure is 130/80 mm Hg, pulse is 60/min, and respirations are 14/min.  Pulse oximetry shows 96% on room air.  Physical examination reveals moist mucous membranes, normal jugular venous pressure, clear lung fields, and normal first and second heart sounds.  There is trace edema of the lower extremities bilaterally.  Neurologic examination is within normal limits.  Complete blood count, basic metabolic panel, troponin, and chest x-ray are normal.  ECG reveals normal sinus rhythm, Q waves in leads V2 to V4, normal QRS complex duration, and normal QTc interval.  Transthoracic echocardiogram shows an apical wall motion abnormality with ejection fraction of 40%.  Which of the following is the most likely cause of this patient's syncope?

• A)Acute pulmonary embolism
• B)Carotid sinus hypersensitivity
• C)Orthostatic hypotension
• D)Vasovagal syncope
• E)Ventricular tachycardia

---

Definitions:

Confidence Interval Estimate

A statistical method used to express the uncertainty associated with a sample statistic by specifying an interval likely to encompass the true population parameter.

Standard Error

A statistic that measures the accuracy with which a sample distribution represents a population.

Sample Size

The number of observations or replicates included in a sample from a population for the purpose of statistical analysis.

Correlation Coefficient

A numerical measure that quantifies the degree of relationship or dependence between two variables, typically ranging from -1 to 1.