When the buck stops the heart

THE PHYSICIAN AND SPORTSMEDICINE - VOL 25 - NO. 4 - APRIL 97

Summertime may be too early for deer hunters to buy their permits, but it's not too soon for them to get physically conditioned for the autumn ritual. The excitement of sighting and shooting a deer, the strain of hauling heavy equipment and dragging a deer, and related environmental stresses place demands on the heart that increase the risk of having a heart attack, according to a recent study (1).

"The average person doesn't realize just how physically taxing deer hunting can be," says Susan Haapaniemi, MS, an exercise physiologist at William Beaumont Hospital in Royal Oak, Michigan, and lead author of the report.

She and her colleagues rounded up 25 male deer hunters, average age 55 years, and measured their peak heart rates during a treadmill test. Seventeen of the men had been diagnosed previously with atherosclerosis. The hunters were outfitted with Holter monitors to measure heart rates while stalking, sighting, shooting, gutting, and dragging a deer, and they kept a log of these activities. The authors presented their findings at the annual meeting of the American Heart Association (AHA) in November 1996 in New Orleans.

Of the 25 hunters, 21 had heart rates greater than 85% (average 94%) of their peak heart rate when merely walking. Heart rates soared as high as 114% of peak (average 83%) when sighting a deer, 118% of peak (average 92%) when shooting a deer, and 116% of peak (average 97%) when dragging a deer. Experts prescribe exercising at no more than 85% of peak, says Haapaniemi, because higher levels can dislodge plaque, which may block a coronary artery, causing a heart attack.

The Holter monitor readings showed that 3 hunters had abnormal electrocardiographic changes during the hunt that were not noted on treadmill testing, and 7 hunters had complex arrhythmias that were not noted on treadmill testing.

The number of hunters who suffer heart attacks in the field is not officially tracked, but unofficial reports from newspapers and paramedics suggest that more die of heart attacks than gunshot wounds, says Haapaniemi. Every hunter has "a story about a hunting friend who was found dead from a heart attack," she says. The highest risk, she adds, is among the people who are most likely to have latent coronary artery disease—sedentary middle-aged or older people who smoke or have high blood pressure or high cholesterol. In Michigan, about a quarter of the 1 million hunting licenses issued each year go to hunters over age 45, Haapaniemi says.

Cardiologist Alain Bouchard, MD, who heard Haapaniemi's presentation at the AHA meeting, plans to educate hunters about cardiac risks at a large outdoor sporting show held each summer in Alabama. A poster will summarize findings of the Michigan study, and cholesterol levels and blood pressure will be checked in cooperation with the American Heart Association. Referrals for stress tests will be made when necessary. Hunters "feel like they're doing themselves some good, walking and exercising, but we don't realize how much demand there is on the heart," says Bouchard, a physician at Baptist Medical Center Princeton in Bir-mingham, Alabama.

For hunters who are out of shape, Haapaniemi recommends these precautions:

Start an exercise program like brisk walking for 30 minutes a day, 4 or 5 days a week, a few months before hunting.
Get a stress test before hunting if you're older than 45 and have one or more of the major cardiac risk factors: smoking, high blood pressure, high cholesterol, or sedentary lifestyle.
Don't drink, smoke, or eat a heavy meal before hunting.
Hunt with a buddy.
Never drag a deer if you have heart disease.
Stop and get medical help at the first sign of dizziness, chest pains, or palpitations.
Take breaks while hunting, especially during long treks over hilly terrain and when dragging a deer.

Carol Potera
Great Falls, Montana

Reference

Haapaniemi SM, Wegner J, Franklin B, et al: Deer hunting: a trigger for acute events?, abstracted. Circulation 1996;94(8):I374

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