FDA says deaths with heart imaging drugs continue

The Food and Drug Administration said that since October it has received four reports of patients dying after receiving injections of the drug Definity. One patient with congestive heart failure died within five minutes of receiving the drug.

The FDA in October placed its most serious warning on the imaging drugs after receiving about 200 reports of serious allergic reactions, seven of which caused death.

The drugs, known as contrast imaging agents, are used in echocardiograms, or ultrasound procedures that show movement of blood through the heart. The agents contain tiny gas bubbles that help doctors spot small clots and other potential heart problems.

The FDA released updated information on negative side effects reported with the drugs ahead of a meeting next week. The agency will ask a panel of outside experts to suggest safety requirements for developing better, safer imaging products.

Definity was marketed by Bristol-Myers Squibb Co. until December, when it sold the drug to privately held Lantheus Medical Imaging, which is based in North Billerica, Mass.

General Electric Co. markets a similar drug called Optison. But the FDA said it recorded fewer safety problems with Optison because GE stopped selling it between 2005 and 2007.

The products have been used millions of times in the U.S. and abroad, according to Ethan Halpern, a radiology researcher at Thomas Jefferson University in Philadelphia. While they are only used in a small percentage of echocardiograms in the U.S., physicians abroad use them to detect problems with the liver and other organs.

Halpern and other imaging specialists argue that many of the deaths reported to the FDA were caused by existing illness, not the chemicals themselves.

"The healthy (patients) who have been given these agents haven't had any problems," Halpern said. The FDA's warnings have made patients unduly cautious about using the agents, "which is a tremendous downside in terms of patient evaluation," he added.