You would know if you had a heart attack, right? Movies and TV shows are filled with depictions of people in the throes of the gripping chest pain of a heart attack, or myocardial infarction (in medical parlance). But here’s the thing: nearly one in two people who experience a heart attack are unaware they’re having one.
A silent myocardial ischemia (SMI), or silent heart attack for the purposes of this book, affects 45 percent, or nearly half, of all heart attack victims, according to the most comprehensive study to date. The Atherosclerosis Risk in Communities (ARIC) Study tracked 9,498 participants of different genders and races, with ages ranging from the forties to the eighties, over a span of a decade. This kind of study, with its longevity—ten years—and its use of real-life people in everyday circumstances, is, by the way, the gold standard for scientific medical research versus the typical study using lab mice over the course of a few months.
Until recently, the accepted estimate of silent or painless heart attacks, a manifestation of silent heart disease, as a portion of total heart attacks was thought to have been only 25 percent, so the latest research nearly doubles the risk that Americans face from silent heart disease. Let’s do the numbers: more than a million Americans have heart attacks every year, and nearly half of them have no idea of the damage being done.
Part of the reason so many Americans suffer from heart disease in general and silent heart disease in particular is because they lack a basic understanding of heart function and dysfunction. Remember that the mantra for this book is knowledge is power; the more you know about your heart, the more empowered you will be as a patient. So consider the four chapters in Part I of this book your heart-health primer. Now, it may remind you a bit of school homework, but the difference is that everybody gets an A for just reading it.