Adenosine stress protocols for nuclear cardiology imaging

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. The aim of this study was the introduction of adenosine stress 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. adenosine 140μg/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 boot 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 fount 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 was a minimum of 45 minutes after stress. Conclusion: This study gives advantages 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.