Which acute event is most likely to occur in a patient who has chronic atrial fibrillation?

Choice A rationale
Cerebral edema is the swelling of the brain due to fluid accumulation, which can occur after excessive alcohol consumption. However, it is not related to myxedema, which is a condition associated with severe hypothyroidism.
Choice B rationale
The deposit of fatty tissue is associated with conditions like hyperaldosteronism, where there is an excess production of aldosterone. This condition does not cause the characteristic skin changes seen in myxedema.
Choice C rationale
Proliferation of tissue behind the eyes, known as exophthalmos, is common in hyperthyroidism, particularly in Graves’ disease. Myxedema, on the other hand, is related to severe hypothyroidism and involves different pathophysiological mechanisms.
Choice D rationale
Myxedema is characterized by the accumulation of mucopolysaccharides in the skin and other tissues, leading to swelling and thickening of the skin. This condition is a result of severe hypothyroidism and can lead to a myxedema crisis if left untreated.

Choice A rationale
Hypokalemia can cause muscle weakness and cramps, but it does not typically lead to severe muscle spasms causing exhaustion. The patient’s symptoms of lethargy and weakness are more likely related to electrolyte imbalances and dehydration rather than muscle spasms.
Choice B rationale
While low potassium levels can affect cellular metabolism, the primary issue here is not glycolysis. The patient’s symptoms are more consistent with dehydration and electrolyte imbalances rather than a metabolic shift to glycolysis.
Choice C rationale
Hypokalemia can cause cells to become hyperpolarized, leading to muscle weakness and decreased reflexes. However, the patient’s symptoms of lethargy and weakness are more likely due to dehydration and electrolyte imbalances rather than cellular hyperpolarization.
Choice D rationale
Hypernatremia, or high sodium levels, can cause cellular dehydration, leading to symptoms such as lethargy and weakness. The patient’s lab results and clinical presentation are consistent with hypernatremia-induced cellular dehydration, which explains his symptoms.