Researchers said that people used to think that if someone had coronary disease, they ould eventually have a heart attack.
This finding may help people realise that, through their choices, they have greater control over whether they ultimately have a heart attack.
The researchers studied patients with different severities of coronary disease who had or had not suffered a heart attack.
The patients were identified by linking 700,000 patients which contains 23 million individuals within extended family pedigrees.
While severe coronary artery disease can be inherited, the presence of heart attacks in people with less severe coronary disease was not clustered in families, the findings showed.