In considering the romantic spirit of the holiday, the human heart is often viewed as the seat of courage, hope and love. With regard to its more earthly functions, however, the heart is no less remarkable. It is this less metaphysical, but equally amazing role that riveted my interest early on in medical training and continues to fuel my passion for cardiac health in medical practice today.
From an engineering standpoint (nerd alert), the heart is an elegant electromechanical pump responsible for the timely delivery of oxygen and nutrient-rich blood to the cells of the body, returning metabolic products such as carbon dioxide to the lungs, and excess fluid and wastes to the kidneys for export. An average adult heart pumps a person's total blood volume of five liters through the body in about one minute in a closed circuit of 60,000 miles of blood vessels. With exercise, stress or increased demand from muscles or organs this flow rate can double in a healthy person.
The heart accomplishes these tasks in response to chemical messages in the body called hormones, released by the endocrine system to maintain blood flow to the vital tissues of the body. In response, the heart can increase or decrease the rate (pulse) or stroke volume of each beat. These signals may be sent as a result of stress or outside stimuli, or to internal changes to maintain body function. With this constant flow of information the heart continues to pulsate in its measured rhythm, driving the lifeforce of the myriad systems working in harmony.
The contraction of each beat is a concerted, fluid movement that starts with an electric signal created by calcium and potassium ions lining up like Rockettes. They are then released along conduction pathways and that excited spark spreads over the heart in a chain reaction that becomes a choreographed wave. The resulting current blooms upward and causes a fluid muscle contraction of the heart, moving blood on its continued journey.
Unfortunately, the heart does so well at its job that most people pay no attention until there is a problem. While medicine has seen many advances in treatments and procedures for cardiology in the last 20 years, the best cure is still prevention. Fortunately, like the heart itself cardiac health is not rocket science, and in the Valentine spirit here are some ways to lower blood pressure – and cardiovascular disease risk along the way. Some are surprising!
The usual things you hear from the doctor still apply – sleep, exercise, maintain a healthy weight and manage life stress effectively. Avoid abusing your body through unhealthy foods, drugs, tobacco or excessive alcohol. Your heart will thank you for it. But what about the good stuff? What about those chemical messengers that tell the heart to relax, and go to its happy place?
It turns out that among other things hugging, cuddling, kissing and intimacy can release endorphins and dopamine that lower heart stress (we won't talk about chocolate too much here, but there is some data to support its benefits to the heart in modest quantities as well). Similar hormones released with falling in love, or romantic interest also trigger these same pathways that over time can lower cardiovascular disease risk. Maintaining a healthy and supportive emotional relationship is a component of this too, but physical intimacy has also been shown in several studies with decent reproducibility to be of statistical significance in contributing to cardiac and total health. This includes improved immunity, energy and mood.
So when you are with your Significant Other this February 14th pondering affairs of the heart, remember that it is not just about physical attraction. Rest assured that there is chemistry there as well.