Why Is a Prolonged QT Interval Associated with Life-Threatening Heart

question 15

Multiple Choice

Why is a prolonged QT interval associated with life-threatening heart rhythm disturbances?

• A) It is associated with a longer vulnerable period.
• B) Calcium influx is the greatest during this period.
• C) The SA node becomes refractory to the normal depolarization.
• D) This period is refractory to AV depolarization.

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Definitions:

Variability

The extent to which data points in a statistical distribution or dataset differ from the average or mean value.

Median

The middle value in a sorted, ascending or descending, list of numbers.

Mean

The average value of a set of numbers, calculated by dividing the sum of all the values by the count of the values.

Observations

Records or measurements of variables or phenomena of interest, collected during an experiment or study.