11 Cardiac Facts to Take to Heart

Your heart isn't gold. It isn't sweet. And don't put in on your sleeve—you'll make a mess! Just in time for Valentine's Day, here are 11 scientific facts about your ticker.

1. The most common time for a heart attack: Mondays between 8 and 9 a.m. Really!

2. Your muscular heart puts juiceheads to shame. It's theoretically strong enough to lift almost 3000 pounds, and a single heartbeat could shoot blood 30 feet.

3. You know what they say about guys with long ring fingers... They're less likely to have early heart attacks. The British Journal of Cardiology found that men with ring fingers the same length or only slightly longer than their index fingers have a higher risk of heart attacks in their thirties and forties than men with ring fingers much longer than their index fingers. The reason's testosterone, which is responsible for lengthening ring fingers, protecting against heart disease, and professional football.

4. The term "pacemaker" doesn't just refer to an implanted device. The pacemaker cells in the right atrium of a healthy heart control the heart rate. The artificial version relies on electrodes.

5. The average woman's heart beats 78 times per minute. The average man's beats 70 times per minute.

6. The heartbeat theory uses the known difference between average male and female heart rates to predict the sex of babies. Supposedly, 140-plus beats per minute predicts a girl, and under 140 beats is a sure sign of a boy. Doctors claim there's no proven correlation between heart rate and sex in hearts that young and well, unborn. But go ahead, listen to your baby's heartbeat, take a 50 percent chance, and guess. Or get a sonogram.

7. The bigger the heart, the slower the heart rate. The blue whale's heart is the size of a small car and beats only six times per minute.

8. Mammals are warm-blooded, hairy vertebrates that nurse their young. Know what else some scientists say they all have in common? A lifetime of about one billion and a half heartbeats. Obviously, not all creatures have the same longevity—an elephant lives longer than a cat, for instance. That's because larger animals' hearts beat slower. They don't just have more cells. They have more efficient cells.

9. The two sounds of a heartbeat are produced by the valves closing. Their official scientific name is lub-dub (not to be confused with dubstep).

10. Most heart transplants are performed in the United States, but the first one occurred in South Africa on December 3, 1967. The first heart transplant in the U.S. occurred three days later in Brooklyn, New York. But it wasn't your typical heart transplant—it was performed on an infant, who died nearly seven hours later. The next pediatric transplant didn't happen until 1984 in London. It was ultimately unsuccessful. The same year, the U.S. tried another pediatric transplant on an infant called Baby Fae. Because there weren't any appropriate donor hearts, the surgeon tried the next best thing—a baboon heart. Baby Fae lived for three weeks.

Baby Moses, image via LomaLindaHealth.org.

But it gets better! In 1985, Baby Moses was the first infant to undergo a successful heart transplant. Many more babies have survived since. The bigger problem now—for all patients needing transplants—is the limited availability of donor organs. In May 2012, a baby boy in Italy received the world's smallest artificial heart, an 11-ounce titanium device that will eventually be replaced with the real thing.

11. Want to become an organ donor? Good for you—and for the people you'll help someday. You can sign up here.

Meanwhile, the next big thing in the cardiac world is the "beating heart" transplant—and if Edgar Allan Poe were still alive, he'd love it. Harvested hearts start to deteriorate within hours. The longer they take to transplant, the greater likelihood of rejection. Instead of using an ice chest, now scientists are experimenting with heart boxes that will circulate donor blood and keep the heart ticking ... outside the body. This way, the hearts will stay healthy for transplant recipients. Cue the "It's my heart in a box!" jokes.