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What are the guidelines for maximum heart rates during the nuclear heart stress test?

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Posted on Thu, 24 Jul 2014
Question: I will be taking a nuclear heart stress test. What are the guidelines for maximum heart rates during the test. I am 72 with 2 stents in my right coronary artery. Four years ago I had to reach 140 beats /minute. Should I expect the same now/ Thanks.
doctor
Answered by Dr. Indu Kumar (50 minutes later)
Brief Answer:
Target heart rate is same i,e 140 beats/min.

Detailed Answer:
Hello XXXXXXX
Thanks for writing to HCM

Yes,target heart rate is same for you as it was four years back.It is same as 140 beats /min.

During exercise,healthy coronary arteries dilate more than an artery that has a blockage.This unequal dilation causes more blood to be delivered to heart muscle supplied by the normal artery.In contrast, narrowed arteries end up by supplying reduced flow to its area of distribution.
When a "perfusion tracer" (a nuclear isotope that travels to heart muscle with blood flow) is injected intravenously,it is extracted by the heart muscle in proportion to the flow of blood and it can be appreciated by imaging.

The treadmill is stopped when the patient achieves a target heart rate (this is 85% of the maximal heart rate predicted for the patient's age).

However,if the patient is doing extremely well at peak exercise,the treadmill test may be continued further.The test may be stopped prior to achievement of the target heart rate if the patient develops significant chest discomfort,shortness of breath,dizziness,unsteady gait, etc. or if the EKG shows alarming changes or serious abnormal heart rhythm.It may also be stopped if the blood pressure (BP) rises or falls beyond acceptable limits.

Get well soon.
Hope I have answered your question.
Further queries are most welcome.

Take Care
Dr.Indu XXXXXXX
Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar
doctor
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Follow up: Dr. Indu Kumar (7 minutes later)
Thank you for your response. I have to work harder on my daily treadmill sessions before the July test! Have to pass...no excuses.
doctor
Answered by Dr. Indu Kumar (56 minutes later)
Brief Answer:
All the best for target.

Detailed Answer:
Hello XXXXXXX
Thanks for writing back

It is very nice to know that you are preparing so hard.Wish you all the best to achieve the target.

Get well soon.
Hope I have answered your question.
Further queries are most welcome.

Take Care
Dr.Indu XXXXXXX
Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar
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Answered by
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Dr. Indu Kumar

Radiologist

Practicing since :2004

Answered : 6727 Questions

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What are the guidelines for maximum heart rates during the nuclear heart stress test?

Brief Answer: Target heart rate is same i,e 140 beats/min. Detailed Answer: Hello XXXXXXX Thanks for writing to HCM Yes,target heart rate is same for you as it was four years back.It is same as 140 beats /min. During exercise,healthy coronary arteries dilate more than an artery that has a blockage.This unequal dilation causes more blood to be delivered to heart muscle supplied by the normal artery.In contrast, narrowed arteries end up by supplying reduced flow to its area of distribution. When a "perfusion tracer" (a nuclear isotope that travels to heart muscle with blood flow) is injected intravenously,it is extracted by the heart muscle in proportion to the flow of blood and it can be appreciated by imaging. The treadmill is stopped when the patient achieves a target heart rate (this is 85% of the maximal heart rate predicted for the patient's age). However,if the patient is doing extremely well at peak exercise,the treadmill test may be continued further.The test may be stopped prior to achievement of the target heart rate if the patient develops significant chest discomfort,shortness of breath,dizziness,unsteady gait, etc. or if the EKG shows alarming changes or serious abnormal heart rhythm.It may also be stopped if the blood pressure (BP) rises or falls beyond acceptable limits. Get well soon. Hope I have answered your question. Further queries are most welcome. Take Care Dr.Indu XXXXXXX