It’s my understanding that the heart beats a certain number of times per minute, and that the arteries also contract to participate in pushing the blood through the body, and this is called the pulse. We can use a stethoscope (or a chest band) to monitor the heartbeat, and we can just put a finger at some location on the body (wrist, under chin, etc.) to listen to the pulse. Correct?
I know it may seem obvious, but I’ve always seen references to either pulse or heartbeat, but I’m having a hard time confirming that the two are equivalent. So perhaps they aren’t.
So, do the arteries always contract at the same frequency as the heart itself? If the heart beats at 156 per minute, does the pulse also beat at 156 per minute?
Yes, pulse equals heartbeat. Every “pulse” you feel on your wrist or neck corresponds to one “beat” of the heart, each heartbeat being two sounds, one quiet and one louder.
I don’t believe systemic arteries “contract” because gravity works pretty well in getting blood to the rest of the body. Systemic veins do have a mechanism for “pulling” blood against gravity back to the heart. The pulmonary circuit(from the heart to the lungs) is the opposite.
I’m pretty much certain that this was not what you were getting at, but there are, indeed, circumstances where the heart beat and “the pulse” have different values.
In one extreme example, a person’s heart may be beating so ineffectively, or the blood pressure may be so low (due to, say, blood loss) that each beat of the heart is ineffective in producing a palpable (i.e. ‘feelable’) pulse at the wrist or wherever. And, note that the heart beat itself in such circumstances is still easily audible in the chest by using a stethoscope. By the way, this phenomenon leads to the general rule that if you can’t feel the pulse at the wrist, then the (systolic) blood pressure is less than 80. Can’t feel it the neck? Then the BP is less than 60.
A less alarming situation where the beat of the heart doesn’t match the beat as felt and counted at the wrist can occur in the very common condition known as atrial fibrillation. In atrial fibrillation, the priming chamber (atrium) of the heart is not contracting in a coordinated manner and, as well, the electrical impulses traveling from the priming chamber to the main pumping chamber (ventricle) arrive at the latter randomly. The net effect can be for the heart to beat at an irregular rate with only some of those beats powerful enough to create a palpable impulse (i.e. “a pulse”) at the wrist. So, for example, listening over the chest with a stethoscope may reveal a heart rate of 100, but the rate as counted at the wrist could be 60. That is called a ‘pulse deficit’. If anyone’s interested I can elaborate on the mechanism for this occurrence.
I’m not trying to be a pedant, but I don’t think that’s really the case.
Arteries most definitely contract and are endowed with specialized muscle (smooth muscle) to do so. It’s critical that our arteries have the ability to contract for without it, our blood pressure would be impossible to sustain during situations such as blood loss, severe infection, etc., and even getting up from the lying position.
Although the veins (especially in the legs) tend to be affected by gravity, the arteries are not (at least to any meaningful extent under normal circumstances. Thank goodness - otherwise every time we stood up, we could faint).
Really sucks to feel your heart pounding away and still faint.