Heart attacks often come without warning, and although it’s well documented that they’re caused by atherosclerosis (plaque buildup on arterial walls), there are certain triggers that can set off a heart attack in people who are at risk.

Just a month ago, (April, 2011) Belgian researchers published a study in The Lancet ranking various heart attack triggers according to their prevalence in people who are already at risk for heart problems. Here’s a list of some of their more surprising findings, and some ways to protect yourself from heart attack triggers.


Commuters beware: Traffic exposure triggers about 8 percent of heart attacks among those who are vulnerable, and it can affect you if you’re a driver, a passenger, or even a bicyclist riding along the road. Previous research on the link between traffic and heart attacks has been inconclusive as to whether it’s traffic-related pollution, the stress of being in traffic, or some combination of the two that causes heart attacks. But the clear message is that getting stuck in rush-hour jams isn’t good for anybody. If it’s possible, ask your boss if you can work from home one day a week; it may save your ticker. Telecommuters are healthier, past studies have shown, and they even work longer hours while still maintaining a better work-life balance than their colleagues in cubicles.


This was second on the list of heart attack triggers, accounting for just over 6 percent of cases. But they weren’t talking about the good kind of exertion that comes from exercise. The study noted that people who are sedentary most of the time, and then suddenly engage in heavy-duty physical activity, are most at risk. The best protection against this is at least 150 minutes per week of regular exercise. But if you’re already sedentary and need to, say, help carry some blocks to build your house, be sure to warm up first, and delay the strenuous activity till later in the morning. Strenuous exercise first thing in the morning is a shock to your system and can up the risk of a heart attack.


These drinks, whether to get you going or calm you down, each contribute 5 percent to total risk of triggering a heart attack. Heavy alcohol intake is the primary villain, although doctors aren’t sure how it triggers heart attacks. A few theories are that too much alcohol can increase inflammation and interfere with your body’s ability to dissolve blood clots. But keep in mind that one glass of wine or other alcoholic beverage per day can help prevent heart disease because of the beneficial polyphenols in wine and beer. Coffee, on the other hand, seems to work in exactly the opposite way. Most studies linking coffee to heart disease have found that people who drink it less frequently are more prone to heart attacks than people who drink a lot of coffee. So if you drink less than one cup of coffee per day, consider switching to tea to get your caffeine boost.


Smog and vehicle exhaust, and particulates from burning wood combine to form a potent, but silent, killer. Air pollution triggers 4.75 percent of heart attacks among those vulnerable, and even though it’s one of the lowest percentages, the authors considered it most concerning because no one can avoid air pollution. For that reason, environmental cardiologists agree that preventing heart attacks in other ways is more effective than trying to cope on the individual level with air pollution. Minimize stress, treat migraines if you have them, don’t eat red meat and salt, and do eat a Mediterranean diet. You’ll protect yourself against air pollution and all the other heart attack triggers included in the study.


Strong emotions seem to trigger a heart attack even if they’re good emotions. Anger and negative emotions contribute more to your risk – almost 7 percent – than positive emotions, which contribute just 2.5 percent. Both intense positive and intense negative emotions can cause stress to the body.

All strong emotions increase adrenaline output, heart rate, and the stickiness of red blood cells, which combined can trigger a heart attack. But there’s a reason you should still try to embrace more positive emotions to ward of heart attacks. Positive emotions generally result in more balanced heart rhythms than negative emotions, and disrupted heart rhythms are a contributing factor in some heart attacks. Further, because we tend to resist negative emotions, they produce more muscle tension than positive emotions, including tension in the muscles in the periphery of blood vessels. This blood vessel constriction (narrowing) also makes negative emotions more likely than positive emotions to contribute to heart attacks.

No. 6: SEX

Rounding out the top heart attack triggers is sex, which increases your chance of heart attack by 2.2 percent. All that horizontal activity can raise blood pressure and heart rates, triggering a heart event. The various studies looking at the link between sex and heart attacks have all concluded that the risk is still relatively low for healthy people, somewhere around 1 chance in a million. But people already at risk for heart attacks should take it easy.

The good news is that regular exercise can keep you from succumbing to a sex-induced heart attack.

See you next week.