The FDA is warning healthcare professionals of the rare but serious risk of heart attack and death associated with the use of Lexiscan (regadenoson; Astellas) and Adenoscan (adenosine; Hospira), two cardiac nuclear stress test agents.

RELATED: Diagnostic Agents Resource Center

Lexiscan and Adenoscan are both approved for use in radionuclide myocardial perfusion imaging for patients unable to undergo adequate exercise stress. These agents dilate the arteries of the heart and increase blood flow to help identify any obstructions. 

However, Lexiscan and Adenoscan can cause blood to flow specifically to the healthier, unblocked arteries, which can reduce blood flow in the obstructed artery. This reduced flow can lead to a potentially fatal heart attack.

The FDA reported that some adverse events occurred in patients with signs or symptoms of acute myocardial ischemia. 

Cardiac resuscitation equipment and trained staff should be available before administering Lexiscan or Adenoscan. Healthcare professionals should avoid using these drugs in patients with signs or symptoms of unstable angina or cardiovascular instability, as they may be at greater risk for serious cardiovascular events.

The Warnings & Precautions section of both drug labels already contain information about the possible risk of heart attack and death. 

Due to the recent reports of serious adverse events, the FDA has approved changes to the drug labels to include updated recommendations for use.

For more information call (800) 332-1088 or read the FDA Safety Announcement