Tuesday, January 29, 2008

Puffy feet




Several years ago whilst on a summer trip, I looked down with alarm and noticed the tops of my feet squeezing between my sandal straps. That, to me, is one of the surest signs of advancing age--sit for a long while in a car or on an airplane, especially in the summer heat, and poof! your feet puff up. The perfect storm of venous insufficiency: aging veins dilated in an overheated car unable to transport blood efficiently from toes to heart.

Now I'm once again amongst puffy feet, this time not my own. Two of my family members (FMs #1 and #2) are struggling to stuff their feet into shoes for two different reasons:

FM #1: Venous insufficiency plus too much sitting. The road back to the heart from the furthest reaches of your body (that would be your toes) is a long and passive one. While the arteries that carry oxygenated blood from your heart to your body have elastic walls that snap smartly with each beat of the heart, propelling blood along the route, the veins have no such resiliency.

Instead, the veins rely on valves that open with each pulse beat, then close as the heart relaxes, thus preventing the backwash of blood south to the floor with gravity (see picture above of healthy and varicose veins and their valves). If your veins dilate as in varicose veins (and you can have such veins deep in your leg even if you don't see ugly varicosities on the surface), the valves are too far apart to prevent the backflow of blood.

As a result, blood oozes through capillary walls, feet and lower legs swell, and the dilated capillaries and blood pigments released cause an irritating itchy rash (stasis dermatitis). These skin changes over time cause dark pigmentation in the lower legs, and the skin is more easily injured and less easily healed.

Since venous return from the legs is entirely passive, the squeezing action of the leg muscles is an important extra push to keep the blood moving upwards. Prolonged sitting because you're stuck in the middle seat of row 25 in coach, or perhaps because you're so old and your knees so bad that you're disinclined to get up, takes the muscular pump out of the equation. Add gravity sucking blood southwards and there go the feet into puffiness.

FM #2: Right-sided congestive heart failure plus too much sitting. The right side of the heart is responsible for boosting deoxygenated blood returning from the body into the lungs where it can pick up a new load of oxygen. When the lungs are diseased, say from emphysema, the lung tissue is far less efficient at delivering oxygen across the barrier to the blood. The blood vessels constrict in some misguided effort to bypass the damaged part of the lung (but, unfortunately, the whole darn lung is damaged), and the pressure rises in the narrowed arteries.

As a result, the right heart is now working much harder to push blood into these constricted arteries, and it starts to enlarge and fail. With each beat of the heart, less blood is emptied into the arteries heading for the lungs, and blood starts to back up in the body, particularly in the legs and in the liver. Add inactivity due to lung disease to the equation, and the legs and feet puff up.

Whether the lower extremities swell from inactivity, venous insufficiency, or heart failure, the blood is slowed and sludging in the veins of the leg. If Mr. or Ms. Bigfoot has a clotting problem--inherited, secondary to use of oral hormones such as birth control pills or HRT, as a result of cancer, or due to injury or recent surgery--this sludgy blood can clot. Clotted veins in the legs further aggravate the swelling, and if a glump of clot breaks free and travels up the veins and into the lungs, it can cause a pulmonary embolus which further accentuates right heart failure or, if big enough, stops heart function suddenly...and fatally.

6 comments:

Mauigirl said...

I still remember the first time my feet swelled up - it was on a 100 degree day when I'd been sitting outside at a yard sale all day. I immediately thought "heart failure" but realized I was being alarmist, even for me. Another time it happened after having been on a plane.

JeanMac said...

Dr. B runs her ultra sound wand over my legs every year before injecting spider veins.Luckily, I don't show deep veins are involved. Mom passed away from CHF, etc.

Anonymous said...

Out of the blue, my feet will get puffy - mainly the left one. I have been dealing with this for 15 or more years - and have tested all sorts of foodstuffs, salt, you name it - it will last for 3 or 4 weeks, and just as suddenly go away for 3 to 6 and even longer. I've been on HRT for years - and going off it even at my age of 76 is not an option. There are side effects that I am unable to live comfortably with (and no, it has nothing to do with wrinkles, or 'feeling young' - it has to do with dry tissues which cause extreme pain, and other things no one has come up with an answer for)...My doctor checks my heart etc every three months, and thinks the puffiness is not to be worried about. I am curious about its coming and going. Normally my feet are bony, scrawny and the veins on the arch are as noticeable as those on the backs of my hands. Walking a lot or a little makes no difference.

denverdoc said...

Hi Annie,

I don't think your puffy foot is a heart thing, but then I'm not exactly sure what it is.

I do know that when feet puff, the left one tends to bet puffier than the right. This is because the artery that goes to the left leg crosses over the vein, whereas the right side is not arranged artery over vein. As a result, the stiffer artery (filled with blood under full arterial pressure) squashes the softer vein beneath which can partially obstruct blood flow back to the heart from the left foot.

Perhaps your anatomy is particularly compromised by a position in which you sit, a chair that you sit in now and again, or a task that keeps you sitting longer than usual?

I do not think your heart or your HRT is at fault. It does sound like you suffer from "menopausal arthritis" which is not really arthritis but the term for stiff achy joints and limbs from a lack of estrogen. I would be scarcely able to get up from a chair after prolonged sitting if I didn't use estrogen.

Anonymous said...

I am a 31 year old woman that started have one puffy foot, the right one, about 3+ years ago...sometimes it extends up my calf...I have never had an ankle injury...was tested for gout and did not have gout...was given an ultrasound to see if it was due to a stroke and my results for that were normal. I particpate in several aerobic classes a week...run about 10 times a month...I do NOT sit down...pretty much ever:) I'm concerned that none of the doctors that I have seen know what it might be. On my left upper thigh I have a seriously bulging vein that can be hot to touch at times...I'm concerned because heart disease runs rampant in my family, having my mother pass away at the ate of 55...after having open heart surgery at the age of 51. I don't sit at ANY of my jobs...and I remain as active as I can...I'm just looking for a little more insight into what this may be...sometimes when I dry my right leg off oafter a shower I get pins and needles feeling when I run my hands up and down that leg...any suggestions? I am trying yoga once a week to see if it will help...

Karyn Hughes said...

I use a wheelchair all day every day, and my physiatrist says my foot swells from being in one position for too long. I prevent it ny changing my position, and elevating the swollen foot for a while hourly. It seems if you stay in one position for too long, your body has trouble circulating fluid, and it builds in lower digits. He says office workers can have the same issue.