Which is better- treadmill test or nuclear stress test for evaluation of angina? Are there any factors that affect the choice of the test? Thanks for your responses.
Cardiac stress tests measure the heart's ability to respond to external stress. This stress can be applied by physical stimulation (treadmill or stationary bike) while hooked up to an EKG to monitor blood pressure, pulse, and heart rhythm, or pharmacological stimulation can be used (using a drug to stress the heart, example: adenosine).
Either type of stress can be used regardless of the imaging technique:
- Patients can be stressed physically and imaged with nuclear medicine
- Patients can be stressed with medication and imaged with nuclear medicine
- Patients can be stressed physically and imaged with an echocardiogram (non-nuclear)
- Patients can be stressed with medication and imaged with and echocardiogram (non-nuclear)
This is not a complete list, just an example of how nuclear medicine may or may not be used
Imaging of the heart can be done with PET, CMR, SPECT, or an echo cardiogram (ultrasound imaging of the heart). With most techniques a before stress and after stress image will usually be taken.
PET (positron emission tomography) and SPECT (Single-photon emission computed tomography) are both considered nuclear imaging techniques and use ionizing radiation. CMR (cardiac magnetic resonance imaging) and echo cardiogram do not use ionizing radiation.
An article from the European Society of Cardiology e-journal addresses the decision making process of which method to use:
available non-invasive modalities for diagnosis of SCAD differ distinctly in terms of diagnostic accuracies, predictive values, and costs.
In patients with clinically suspected SCAD, three key question need to be answered to determine patient suitability for non-invasive testing, type of stress (exercise vs. pharmacologic), and functional vs. anatomic testing endpoint: 1.What is the clinical PTP? 2.Can the patient exercise adequately? 3.Are there specific conditions precluding ECG interpretation, or patient characteristics (e.g., body habitus, comorbidities, or current medications) limiting the performance or interpretability of available imaging modalities? Local availability and expertise, radiation exposure, and the need for concomitant assessment of hemodynamics or valvular disease are also important factors affecting appropriate test selection in a given individual
The exhaustive list can be found in the article which is linked above.
Wikipedia's article is also a, less technical, general overview of the subject.
Thanks to everyone in the comments for the suggestions and helpful criticism. This is one of my first posts so I really appreciate the feedback!