From the Guidelines
Lexiscan (regadenoson) can be used for cardiac stress testing in patients with significantly reduced left ventricular ejection fraction (LVEF) of 30%. It is actually preferred over exercise stress testing in these patients due to their limited exercise capacity and over other pharmacologic agents like adenosine or dipyridamole. The most recent and highest quality study, 1, suggests that regadenoson has a more favorable side-effect profile and appears safe for use in patients with bronchospasm, making it a suitable option for patients with severe resting LV dysfunction. Lexiscan is administered as a single 0.4 mg intravenous bolus over approximately 10 seconds, followed by a 5 mL saline flush. The radiotracer for imaging is typically injected about 10-20 seconds after the Lexiscan. Patients with severely reduced LVEF should be monitored closely during the test due to potential hemodynamic effects, though Lexiscan generally has a better safety profile in heart failure patients compared to other stressors. The medication works by selectively stimulating A2A adenosine receptors, causing coronary vasodilation without the significant bronchospasm or AV block risks associated with non-selective adenosine. While generally safe in this population, healthcare providers should still be prepared to manage potential side effects including headache, shortness of breath, flushing, chest discomfort, and rarely, more serious cardiovascular complications. Some key points to consider when using Lexiscan in patients with reduced LVEF include:
- Monitoring for potential hemodynamic effects
- Being prepared to manage potential side effects
- Considering the patient's overall clinical status and medical history before administering the test
- Using the test in conjunction with other diagnostic tools to get a comprehensive understanding of the patient's cardiac function. As noted in 1, severe resting LV dysfunction (LVEF 35%) is considered a high-risk feature, and the use of Lexiscan in this population should be carefully considered. However, the benefits of using Lexiscan in patients with reduced LVEF, including its safety profile and ability to provide valuable diagnostic information, make it a useful tool in the management of these patients. Overall, the use of Lexiscan in patients with significantly reduced LVEF of 30% is supported by the available evidence, and it can be a valuable diagnostic tool in the management of these patients.
From the Research
Lexiscan Use in Patients with Reduced LVEF
- Lexiscan (regadenoson) is a pharmacologic stress agent used for radionuclide myocardial perfusion imaging in patients who are unable to undergo adequate exercise stress 2.
- The safety and efficacy of regadenoson in patients with significantly reduced left ventricular ejection fraction (LVEF) have been evaluated in several studies.
Studies on Regadenoson Use in Patients with Reduced LVEF
- A study published in 2018 found that a post-stress decrease in LVEF with regadenoson stress gated SPECT myocardial perfusion imaging was not predictive of severe/extensive coronary artery disease or adverse clinical outcomes 3.
- Another study published in 2013 evaluated the safety and tolerability of regadenoson in 514 SPECT MPI patients with and without coronary artery disease and submaximal exercise heart rate response, and found that regadenoson was safe and well-tolerated in this population 4.
- However, there is limited information available on the specific use of regadenoson in patients with an LVEF of 30% or less.
Considerations for Use in Patients with Reduced LVEF
- Patients with heart failure with reduced ejection fraction (HFrEF) have a significant morbidity and mortality burden, and the management of HFrEF has seen significant scientific breakthroughs in recent decades 5.
- The use of regadenoson in patients with significantly reduced LVEF should be carefully considered, taking into account the potential risks and benefits of the test, as well as the patient's overall clinical condition.
- Further studies are needed to fully evaluate the safety and efficacy of regadenoson in patients with severely reduced LVEF.