Heart Beat: High pulse pressure poses risk for atrial fibrillation
High pulse pressure poses risk for atrial fibrillation
Arteries, like knuckles and knees, can stiffen with age. When this happens, the heart must contract a bit more forcefully with each beat to circulate blood. This extra work can lead to changes in the size and shape of the muscular lower chambers of the heart, the ventricles, much as lifting weights can do to the arms. If the remodeling also affects the upper chambers, the atria, it can throw off the electrical pathways that generate the "contract now" signals that precede each heartbeat.
One measure of arterial stiffness is pulse pressure "" the difference between systolic pressure (the top number of a blood pressure reading) and diastolic pressure (the bottom number). Pulse pressures under 40 are normal; the larger they are above that, the more worrisome. Systolic pressure reflects the pressure in the arteries when the heart contracts; diastolic pressure, when the heart relaxes.
A report from the Framingham Heart Study suggests that high pulse pressures are linked to the development of atrial fibrillation, a common heart rhythm problem characterized by irregular and rapid heartbeats. The percentage of Framingham participants who developed atrial fibrillation over a 16-year period climbed with increasing pulse pressure, from 6% among those with pulse pressures under 40 to 23% of those with pulse pressures above 60.