FDA: Nuclear stress test agents carry fatal risks

The U.S. Food and Drug Administration has issued a warning that there is a rare but serious risk of heart attack or death associated with the use of cardiac nuclear stress test agents Lexiscan (regadenson) and Adenoscan (adenosine).

The two agents are FDA approved for use during cardiac nuclear stress tests for patients who cannot exercise adequately.  The agency approved adenosine in 1995 and regadenoson in 2008 for radionuclide myocardial perfusion imaging. Each of the agents dilate coronary arteries and increase blood flow to help spot blockages.

According to Medscape Medical News, an FDA review of the FDA adverse event reporting system (FAERS) database found 26 cases of myocardial infarctions (MI) and 29 deaths that occurred with the use of regadenoson since its approval in 2008, and six cases of myocardial infarctions and 27 deaths associated with the use of adenosine since that drug was approved in 1995.

According to the FDA, with Lexiscan the most common adverse events associated with death were cardiac arrest, MI, loss of consciousness, respiratory arrest, electrocardiogram ST segment depression, pulmonary edema, and ventricular fibrillation. With Adenoscan, the most common adverse events associated with death were cardiorespiratory arrest dyspnea, cardiac arrest, respiratory arrest, and ventricular tachycardia.

The FDA advised that use of these drugs should be avoided in patients who have symptoms of unstable angina or cardiovascular instability.

The two agents in question are manufactured by the pharmaceutical developer Astellas. "Astellas takes its safety reporting obligations very seriously," the firm said in a statement issued to AuntMinnie.com. "We have been working with the FDA to ensure healthcare practitioners are aware of the latest safety information about our products that has been reported through routine postmarketing monitoring so that they are able to make informed treatment decisions."

To learn more:
- read the FDA warning
- read the article in Medscape Medical News
see the article in AuntMinnie.com