Scottish researchers say by screening the relatives of middle-aged heart attack sufferers many lives would be saved.
Past research has indicated in many illnesses hereditary factors play a significant role and this is particularly true of heart disease.
One in every five heart attacks happen to middle-aged patients and the researchers suggest that if direct relatives were screened for their risk for heart disease 42% of premature heart attacks could be prevented.
It is already well known that the siblings and children of younger heart attack victims (under 55 years in men and 65 years in women) have a high risk of heart disease, and though there are set guidelines such people are not as a rule routinely assessed.
The researchers from the University of Glasgow believe that if key signs for risks such as high blood pressure and cholesterol in family members were identified and treated many premature heart attacks would be prevented.
Children and partners are often also at increased risk from lifestyle factors, such as smoking and a diet too high in saturated fats.
The researchers estimated that the 15,600 patients admitted for heart attack in 2004 in England and Wales had 32,000 siblings and they then calculated that 218 of those would have a heart attack within a year and 1,148 would have a heart attack within five years; of that number the researchers say four out of every ten were preventable.
Experts assess an individuals' risk on the basis of hereditary and lifestyle factors such as diet and smoking as well as weight, blood pressure and cholesterol.
They recommend that anyone with a 20% 10-year risk of having a heart attack or stroke should receive preventive treatment, such as cholesterol-lowering drugs called statins.
Professor Jill Pell, who was the lead study author says one method would be to assess the whole adult population, but that would be a big undertaking.
Professor Pell suggests a more efficient method would be to screen the relatives of heart attack victims which she says would produce a much higher hit rate and for every 14 people admitted to hospital with a heart attack one more could be saved.
The researchers are now planning a pilot study in Glasgow to assess the impact of such a screening programme in a busy city hospital.
The British Heart Foundation recommends the following tips for a healthy heart:-
Stop smoking, cut down on salt, eat a healthy balanced diet with plenty of fresh fruit and vegetables, oily fish, starchy foods such as wholegrain bread, pasta and rice; limit alcohol to one to two units a day, exercise, watch your weight, get blood pressure and cholesterol levels checked regularly by your doctor, learn to manage your stress levels and check your family history.
The research is published in the British Medical Journal.