Final answer:
The patient should withhold beta-blocker medication and consult their healthcare provider if they experience a heart rate of 52 beats per minute, indicating a potential case of bradycardia.
Step-by-step explanation:
The nurse should instruct the patient to withhold the medication and consult the prescribing health care provider if they experience a heart rate of 52 beats per minute. Beta-blockers, which are prescribed for hypertension, work by blocking the beta-1 receptors and slowing the heart rate. A heart rate that low could indicate bradycardia, a potential side effect of beta-blockers, which can be serious and warrants medical attention. While a heart rate of 122 beats/minute and a blood pressure of 160/74 mmHg are also concerning, they are not immediate indications to withhold beta-blocker therapy without further assessment from a healthcare provider. A blood pressure of 118/74 mmHg is within normal range and would not generally require withholding of the medication.