Sure, we all know that having your blood pressure checked regularly can save your life. High blood pressure can lead to heart attack and stroke, sometimes with no prior symptoms or warning signs. That’s why you now see blood pressure and pulse monitoring machines in most pharmacies and drug stores, conveniently placed where you can use them while you wait for your prescription.
But despite all the benefits of regular blood pressure checks, by the time you’re actually having a heart attack, it’s a bit late, right? The damage is done.
While a blood pressure check at that late date may give the paramedics some important information, it’s not going to save your life. Strangely, though, the blood pressure cuff itself just might.
That’s the finding of a 2010 study in the Lancet (read a good summary here). Basically, if you have a heart attack, you undergo something called ischemia, a condition in which blood movement and access to tissues is restricted. During a myocardial infarction (MI)—a heart attack—the heart itself experiences ischemia, getting little or no blood, causing tissue to die.
Not too surprisingly, the best response paramedics and emergency departments can provide is to get the blood flowing again quickly. That causes reperfusion, the movement of blood back into the areas that were not receiving any. What researchers are finding is that reperfusion itself, the very outcome you must experience in order to survive a heart attack and avoid as much of the heart damage as possible, could be responsible for additional damage and, in some cases, death.
Think about what happens when you stand up after your leg falls asleep. All that blood suddenly flowing back into the muscle tissue causes pain, tingling, and difficulty walking. A similar thing is happening with coronary reperfusion: blood is suddenly rushing back, potentially causing harm in the process.
Here’s where the blood pressure cuff comes in: it turns out that creating ischemia in the body (even in a different, “remote” area such as the upper arm) for just a few minutes at a time can reduce the damage caused by reperfusion. In other words, if you squeeze a big blood vessel hard, like you do in taking blood pressure with a blood pressure cuff, you are causing a small amount of ischemia. This in turn protects the body against later, more severe ischemia and from reperfusion injuries.
Just a few five-minute cycles of cuff use in the prehospital setting can lead to significantly improved outcomes. In the Lancet study, patients who had cuff applications during transport to the hospital saw significantly greater survival of cardiac tissue, not only good in itself but also a good indicator of long-term outcomes.
So remember, if you want to prevent a heart attack, you should check your blood pressure regularly. But if you’re helping someone who’s already having one, get out that cuff and give them a few good, strong squeezes. It could save their heart—and possibly their life.