Many men with heart disease fear that having sex could kill them, but new research shows the danger is slight.
The news is most welcome for patients with heart problems who aren't sure if sex could be unsafe, Chugh said.
"People will ask their doctors if sex increases their risk of sudden death, and we've never had the answer before because there never was a study", said Chugh, the study's senior author and a highly respected expert on sudden cardiac arrest.
Sudden cardiac arrest is when the heart suddenly stops beating, and usually occurs without warning.
In total, the scientists identified 4,557 SCAs in Portland during the 13-year study period.
Sex is a "recognised trigger" for sudden cardiac arrest (SCA), which causes 300,000 deaths a year in the United States, but the overall rates are low, the report in the Journal of the American College of Cardiology says.
Anxious whether your heart is strong enough for sex? "Now we have data and we can say to them the risk is very low". Black men are more at risk than other populations, accounting for 19 percent of sex-related cardiac arrest.
What is a Heart Attack? The researchers and their teams talk to the patient who gets a heart attack and also from the relatives of some who's closed one gets died due to cardiac arrest. Almost 20 percent of people survived in sex-related cases, compared to only about 13 percent survival odds for other patients.
The examination was introduced at a meeting of the American Heart Association.
Only about 1 in 100 men and 1 in 1,000 women experience sudden cardiac arrest during sexual activity, the study found.
Even though sudden cardiac arrest during sexual activity was witnessed by a partner, CPR was performed in only one-third of the cases.
Dr Chugh said: "These findings highlight the importance of continued efforts to educate the public on the importance of bystander CPR for sudden cardiac arrest, irrespective of the circumstance".
The average age was 60.3 years for people who had a heart attack during sex, compared to 65.2 years for sudden cardiac arrest not linked to the activity.