more PET scan questions

[mason__0]

  had a positive thalium (cardoilite) stress test at a heartrate of  147 bpm three months after bypass surgery. dark area of 20-25% on back side of heart. (age 55, generally fit, able to walk 45 minutes  at brisk rate, no noticeable pain, well controlled non insulin dependent type two diabetes, total chol =138)  Would  a PET scan be a  logical next step, before an
  angiogram?   How do the two compare with regard to  risk, accuracy, cost?
  If I came to  CC for the  PET scan' is it  an outpatient procedure or would it be more than a day?
  
  Thanks for any information you can provide

[CCF Cardio MD - MTR]

Dear Mason, thank you for your question.  A PET scan is generally reserved for situations where the thallium test is ambiguous or the results are obscured by obesity (which can make the images of a thallium test suboptimal).  If your thallium test generated good quality images, then a PET scan may not be necessary.  However, this is a complicated decision that takes into account the exact anatomy of your coronary artery blockages, where the bypass grafts were placed, and your present symptoms.  There is little risk to a thallium or PET scan, but the tests are different.  During a PET scan, a medication called persantine is used to simulate exercise since the images cannot be obtained quickly enough after you step off the treadmill and wait to get under the camera.  Thus, you are in the camera and images are obtained while you are receiving the persantine infusion.  However, a PET scan generally costs twice as much as a thallium test.  Only your cardiologist can determine whether or not you need a PET scan, an angiogram, or no further tests. We would be happy to evaluate you here at the Cleveland Clinic so just follow the directions below to make an appointment.  
I hope you find this information useful.  Information provided in the heart forum is for general purposes only.  Only your physician can provide specific diagnoses and therapies. Please feel free to write back with additional questions.  Good luck!
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