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Adenosine stress protocols for nuclear cardiology imaging
B Baskot1, S Obradovic, S Rafajlovski
1Nuclear Medicine Institute, Military Medical Academy, Belgrade, Serbia. baskotbranislav@yahoo.com
Insights
The AdenoEX protocol, combining adenosine with light exercise, is superior to the AdenoSCAN protocol for myocardial perfusion imaging (MPI). It offers better patient tolerance, improved image quality, and faster imaging times for coronary artery disease assessment.
Area of Science:
- Cardiology
- Nuclear Medicine
- Diagnostic Imaging
Background:
- Myocardial perfusion imaging (MPI) with treadmill stress testing is standard for coronary artery disease (CAD) assessment.
- Pharmacologic stress testing is a viable alternative for patients unable to perform treadmill tests, comprising 40% of nuclear stress tests.
- Adenosine stress protocols are increasingly used for pharmacologic stress MPI.
Purpose of the Study:
- To introduce and evaluate adenosine stress protocols in a nuclear laboratory setting.
- To compare the frequency and severity of side-effects between two adenosine stress protocols: AdenoSCAN and AdenoEX.
- To determine optimal imaging times for each protocol.
Main Methods:
- Two adenosine stress protocols were performed on 186 patients undergoing MPI with 99mTc-sestamibi.
- The AdenoSCAN protocol involved intravenous adenosine (140 µg/kg/min for 3 min) in 47 patients.
- The AdenoEX protocol combined adenosine with low-level bicycle exercise (50W) in 139 patients.
Main Results:
- The AdenoEX protocol was well-tolerated by all patients, with reduced side-effects and improved image quality compared to AdenoSCAN.
- AdenoEX demonstrated a significantly better heart-to-liver ratio.
- Optimal imaging time for AdenoEX was established at 15 minutes post-stress, versus a minimum of 45 minutes for AdenoSCAN.
Conclusions:
- The AdenoEX protocol offers advantages over AdenoSCAN, including fewer side-effects and enhanced patient tolerance.
- AdenoEX improves image quality and increases laboratory efficiency through earlier imaging.
- AdenoEX is a preferred adenosine stress protocol for MPI in CAD assessment.
Unlabelled:
The treadmill test combined with myocardial perfusion imaging (MPI) is a commonly used technique in the assessment of coronary artery disease (CAD). However, there is a group of patients who may not be able to undergo the treadmill test. Pharmacologic stress testing is increasingly utilized for stress perfusion imaging and currently accounts for nearly 40% of all nuclear stress testing [8]. The aim of this study was the introduction of adenosine stress protocols in our nuclear laboratory, and the following, recording and comparing of the frequency and severity of side-effects.
Methods:
We performed two kinds of adenosine stress protocols on 186 patients who underwent MPI with radiotracer 99mTc-sestamibi: 1st: 47 patients underwent AdenoSCAN abbreviated protocol IV. adenosin 140microg/kg/min for 3 minutes; 2nd: AdenoEX combined with low level 50W bicycle exercise in 139 patients. We followed and compared side-effects (minor and major events) between AdenoSCAN and AdenoEX protocol, and established an adequate time for imaging of both protocols.
Results:
Compared with AdenoSCAN, AdenoEX protocol was tolerated by all patients; it reduced all side-effects and improved image quality. Using AdenoEX protocol we found that the heart-to-liver ratio was significantly better, and we established a time of imaging of 15 minutes after stress, compared to the AdenoSCAN time of imaging which was a minimum of 45 minutes after stress.
Conclusion:
This study gives advatages to AdenoEX protocol, because it had fewer side-effects, improved patients' tolerance, improved image quality, and enhanced efficiency and throughput given the opportunity for earlier imaging.
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