You are a physician. A patient comes in complaining about lethargy for the past few weeks. Through an ECG you discover that her SA node shows signs of damage. What do you tell the patient?
a. You explain that the SA node is the pacemaker. She needs cardiac surgery ASAP to repair her SA node before it gets worse or she risks having her heart stop
b. Her AV node is taking over the job of pacemaker so she has a slower heart rate and therefore less cardiac output and less energy than she should
c. She would benefit from an artificial pacemaker that could deliver a higher rate of rhythmic depolarizing current to the SA or AV node
d. probably b and c
Answer: d. probably b and c
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