When Sudden Cardiac Death Happens Without Warning

Almost half of people who experience sudden cardiac death were never diagnosed with cardiovascular disease (CVD) before it was too late, warn investigators.

“A substantial number of deaths happen in people we don’t see in the cardiac ward,” said Tobias Skjelbred, MD, a cardiologist at Copenhagen University Hospital and lead author of a new nationwide study from Denmark, which was published in JACC: Clinical Electrophysiology.

The investigators looked at the more than 50,000 deaths in Denmark in a single year and identified 6851 sudden cardiac deaths. Of those, almost half — or 3046 — had no history of CVD.

The study highlights the importance for both physicians and patients to be aware that sudden cardiac death does not only affect those who have severe CVD.

“The largest subgroup of sudden cardiac death is people without a prior diagnosis,” said Skjelbred. “In terms of absolute numbers, for people under 70, there were more deaths among those who didn’t have a diagnosis than those who did.”

Deaths in Younger People Without a Diagnosis

Preventative measures that exist today are based on risk stratification of more severe cardiac diseases, Skjelbred explained. “If you don’t have a known cardiovascular disease, you’re not eligible for prevention under today’s clinical guidelines.”

People aged less than 70 years, women, and those living alone were less likely to have a diagnosis of CVD before death. People who had lower socioeconomic status, less education, or who lived in more remote areas were also less likely to have a diagnosis.

These latest numbers show that people are getting left behind, Skjelbred acknowledged.

Nicholas Noiseux, MD, a cardiac surgeon at the University of Montreal Health Centre, Montreal, Quebec, Canada, also highlighted the importance of prevention. But that means patients who are at risk need to be identified and diagnosed earlier, and the fact that the first presentation of disease in almost half of patients is death shows that this is not happening, he said.

“This doesn’t mean the problem wasn’t there,” he said. “Most of the time it was, it just wasn’t diagnosed.”

Physicians need to be more aware of the different ways that CVD can present — especially in women who often don’t show the same symptoms as men — said Noiseux. And both doctors and patients should pay more attention to CV health in younger people, to catch warning signs like high blood pressure and cholesterol earlier so preventative measures can be taken.

Skjelbred said that while it is important to develop better risk stratifications for people with known CVD, this study also shows that it is necessary to develop a risk level for the general population as well.