For rabid fans of the New York Giants and New England Patriots, this Sunday’s Super Bowl won’t be just a game. It may be a health hazard. Heart attacks and other cardiac emergencies doubled in Munich, Germany, when that nation’s soccer team played in World Cup matches, a new study reports.

While history suggests European soccer fans can get a bit more worked up than the average American football fan, doctors think there are some valid warnings to be shared.

“I know a little bit about the Super Bowl,” study author Dr. Gerhard Steinbeck of Ludwig Maximilians University in Munich said in a telephone interview. “It’s reasonable to think that something quite similar might happen.”

He and his colleagues present their results in Thursday’s New England Journal of Medicine. They blamed emotional stress for the heart problems, but they note that lack of sleep, overeating, wolfing down junk food, boozing and smoking might have played a role too.

Previous studies suggest that events like earthquakes and war can boost the risk of heart problems. Findings for soccer have been inconsistent.

The new work “confirms something people have been highly skeptical about … that soccer (would) produce that kind of emotional investment that might trigger a heart attack,” said psychologist Douglas Carroll of the University of Birmingham in England.

“People who are not interested in sport find it very difficult to comprehend this,” said Carroll, who in 2002 reported a link between World Cup soccer and heart attacks in England.

The new paper included heart attacks, cardiac arrests, episodes of irregular heartbeat and activations of automatic implanted defibrillators. The researchers noted the number of cases reported in the greater Munich area during World Cup competition in Germany in the summer of 2006. They compared that to the totals for similar periods in 2003 and 2005, and for several…