The study, reported in the American Journal of Cardiology, focused on men who had at least one parent who'd had a heart attack before the age of 55.

That's considered "premature" heart disease, and people whose mom or dad had it are also at higher-than-average risk themselves.

That means increased odds of both heart attack and heart failure. Heart failure is a chronic condition in which the heart can't pump blood efficiently enough to meet the body's demands -- causing symptoms like fatigue, breathlessness and fluid buildup in the limbs.

In the new study, researchers found that among men with a parental history of premature heart attack, those with a healthier lifestyle were less likely to develop heart failure over two decades.

Healthy habits included not smoking, exercising regularly, keeping a normal weight and drinking alcohol in moderation.

"Our study gives more incentive to follow what's generally recommended for lowering the risk of heart attack," lead researcher Dr. Owais Khawaja, of Brigham and Women's Hospital and Harvard Medical School in Boston, said in an email.

Heart attacks are one of the major causes of heart failure because they can permanently damage portions of the heart muscle.

Heart failure can also be caused by uncontrolled high blood pressure or clogged heart arteries. And a healthy lifestyle cuts the odds of those conditions as well.

The findings are based on data from the Physicians' Health Study, which has followed more than 20,000 U.S. male doctors since the 1980s. Just over 1,100 men had a parental history of premature heart attack.

At the start of the study, the men were surveyed about their lifestyle habits. They were given a "good" lifestyle score if they followed at least three of four healthy habits: exercising at least once a week, not smoking, keeping a normal weight and drinking alcohol weekly (rather than more heavily or infrequently).

Over about 22 years, 190 men suffered a heart attack and subsequent heart failure. That included 25 of the men with parents affected by early heart disease.

Those men were at greater risk compared with men without such a family history. But a healthy lifestyle seemed to trim some of the excess risk.

Of genetically at-risk men with a "good" lifestyle score, the rate of heart attack followed by heart failure was about seven cases per 10,000 men each year. That compared with 14 cases per 10,000 among at-risk men with a "poor" lifestyle score.

Even with a healthy lifestyle, genetically at-risk men were more likely to develop heart failure than their peers without a risky family history.

Health-conscious men with no genetic risk were diagnosed with post-heart attack heart failure at a rate of three cases per 10,000 each year. The rate for men with no risky family history but "poor" lifestyle score was between five and six cases per 10,000.

The findings suggest that people who are genetically vulnerable to heart disease can still do something about it.

"Even if the genetic profile is not favorable," Khawaja said, "one can still attenuate the risk by following a healthy lifestyle pattern."

SOURCE: bit.ly/IxE9bA American Journal of Cardiology, online April 18, 2012.

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