By: Jean Johnson for Veins1
Blood Clots – The Good and The Ugly
The ability of the blood to clot, sealing over wounds within moments is a wondrous thing. From cuts and scrapes on a toddler’s knee to blood draws and surgery as we age, we can thank the clotting mechanism for keeping blood in the human body where we want it.
The problem, of course, comes when blood clots form within the arteries and veins. We can get clots from a number of things like sluggish circulation in the legs and accumulations of sticky plaque in the arteries – otherwise known as atherosclerosis, a condition in which fatty deposits and blood platelets collect on the wall of blood vessels.
|Stroke – Know What to Watch For:
According the the National Institutes of Health, sudden development of one or more of the following indicates a stroke. “Usually, as SUDDEN development of one or more of the following indicates a stroke,” according to the National Institutes of Health:
Weakness or paralysis of an arm, leg, side of the face, or any part of the body
Numbness, tingling, decreased sensation
Slurred speech, inability to speak or understand speech, difficulty reading or writing
Swallowing difficulties or drooling
Loss of memory
Vertigo (spinning sensation)
Loss of balance or coordination
Mood changes like depression or apathy
Drowsiness, lethargy, or loss of consciousness
Uncontrollable eye movements or eyelid drooping
The NIH adds that: “If one of more of these symptoms is present for less than 24 hours, it may be a transient ischemic attack (TIA). A TIA is a temporary loss of brain function and a warning sign for a possible future stroke.
While exercise and better eating habits can help people avoid this fate, physicians across the board recognize that it is difficult for patients to make these types of behavioral changes. Consequently a number of treatments have been developed to address various types of clots from the thrombus that remains stationary in places like the brain to the embolism that is a clot which has broken loose and moves through the bloodstream often causing either a stroke or heart attack.
Findings Dramatically Alter Scientist’s Understanding of Clotting Fibers
It’s too early to tell how the new research, published in the August 2006 issue of Science, will enhance current treatments for unwanted blood clots. Still, assistant professor of physics at Wake Forest University School of Medicine in Winston-Salem and one of the lead authors of the study, Martin Guthdold, PhD, said that one company which produces an ultrasonic device to break up blood clots has already inquired after the team’s findings. In particularly the business is interested in the finer points related to how much force is needed to break up clots, presumably so they can reconfigure their equipment to these parameters.
At issue is the ability of clotting fibers to stretch considerably further than formerly thought. Elasticity has long been known to be a property of the fibrin fibers that accumulate in blood clots. But by parlaying two microscopes – including an impressive sounding “atomic force microscope” – into a single instrument, Guthold and his team who worked closely with researchers from the University of North Carolina at Chapel Hill, were able to both see and stretch the fibers.
In the process came the unexpected findings: The fibrin fibers, that along with a protein called factor Xlla make up three-dimensional clots, are far more elastic that anyone suspected. Indeed, on the average, the fibers could stretch almost three times their length and still return to normal. More, it wasn’t until the fibrin fibers were stretched to four times their length that most of them broke. Breaking, of course, is precisely what physicians who treat unwanted blood clots want to see happen.
As Guthold said in a Wake Forest University press release, “This was a stunning revelation because people hypothesized that these fibers stretched but broke much easier. In some cases, fibrin fibers had the ability to be stretched more than six times their length before they broke.” Add this capability of blood clots that can stick like long lost friends to the gunk that can latch onto the wall of an artery or vein artery wall, and it’s clear why the medical community has thus far had mixed results managing interventions for blood clots – and the ensuing strokes and heart attacks these blockages in the circulation can cause.
As Guthold added, “For all naturally-occurring fibers, fibrin fibers are the ones you can stretch the furthest before they break… The fibrin fibers need to stop the flow of blood, so there is a lot of mechanical stress on those fibers. Our discovery of these mechanical properties of individual fibrin fibers show that these fibers likely endow blood clots with important physiological properties. They make blood clots very elastic and very stretchable.”
Also, as one of Guthold’s team members, associate professor of biochemistry at Wake Forest, Roy Hantgan, PhD, who approaches the work more from the medical side, said, “Knowing that the fibrin strands that make up a human blood clot are more stretchable than a spider’s web helps us to understand how clots can seal wounds tightly and withstand the pressure in our blood vessel. This new information also helps us to understand how tough it is to remove a clot that is preventing blood flow to a person’s heart or brain, causing a heart attack or stroke.”
Blood Clots, Their Complications, and Their Treatments
The problem with clots – or globs of coagulated blood comprised of fibrin fibers and factor Xlla – is that they can either partially or fully block the flow of blood through an artery or vein. When this happens in the brain physicians call it a stroke, and every 45 seconds another American has one according to the National Institutes of Health.
The rapid onset of deterioration is why it’s so important to get help right away with both strokes and heart attacks. Tissue that is cut off from blood supply gets ischemic, or marginal, immediately and if the blood supply does not return quickly, it can die or as physicians put it, turn necrotic. Whatever the term one uses, the point is that whatever function the tissue was formerly responsible for can be irretrievably lost.
As far as treating clots, a number of prescription anticoagulants and anti-platelet agents are on the market. Also, some physicians have their more senior patients taking an aspirin a day as a preventative measure against unwanted clotting due to poor venous return in the legs or plaque buildup in the arteries.
Carotid endarterectomy is another approach, although having surgery where you are kept awake enough to respond to the operating team’s questions is reportedly not the most fun experience patients want to put themselves through – even though a local anesthetic is used and there is no pain. Surgeons doing endarterectomies, however, can restore more adequate blood flow to the internal carotid artery and help both prevent strokes as well as hopefully avoiding a second stroke in a patient who has already suffered one.
Angioplasty with a stent placement – in which experts on the circulation system go in through a large artery and use a balloon to open up the clogged area which they keep open with the stent – is an alternative to the endarterectomy. Although angioplasty was formerly used exclusively for the heart, as interventional radiology has developed, specialists are increasingly using it on blood vessels leading to the brain as well.
If these procedures sound like experiences best avoided, consider the reaction normal. If the news that science is marching on to further fathom the workings of the human body sounds good, ditto.
In the meantime, stay active and shoot for three to four hours a week up on your feet and moving as vigorously as you can. Added to that, focus on a healthy diet.
If everyone does their part, scientists and the public, hopefully we’ll all come around right in the end.