Researchers from Imperial College London said more research is urgently needed to establish whether it is possible to predict the risk of fatal heart attacks in patients for whom this condition was not recorded as the main reason for hospital admission.
Heart attacks are caused by a decrease in blood flow to the heart, usually as a result of coronary heart disease.
However, some heart attacks have more subtle symptoms and may therefore be missed or overlooked.
In the study, researchers examined records of all 446,744 NHS hospital stays in England between 2006 and 2010 that recorded heart attacks, as well as the hospitalisation history of all 135,950 heart attack deaths.
Also Read
The records included whether or not patients who died of a heart attack had been admitted to hospital in the past four weeks and if so, whether signs of heart attack were recorded as the main cause of admission (primary diagnosis), additional to the main reason (secondary diagnosis), or not recorded at all.
As many as 21,677 (16 per cent, or one in six) of the patients who died from heart attack had been hospitalised during the four weeks prior, but heart attack symptoms were not mentioned on their hospital records.
There are certain symptoms, such as fainting, shortness of breath and chest pain, that were apparent up to a month before death in some of these patients, researchers said.
These results suggest that possible signs of upcoming fatal heart attack may have been missed.
The researchers also found that of all patients admitted with a heart attack, those whose heart attack was recorded as secondary to the main condition were two to three times more likely to die than patients whose records stated heart attack as the main condition.
"Doctors are very good at treating heart attacks when they are the main cause of admission, but we don't do very well treating secondary heart attacks or at picking up subtle signs which might point to a heart attack death in the near future," said Perviz Asaria, from ICL.
Disclaimer: No Business Standard Journalist was involved in creation of this content