Chronic venous insufficiency, commonly known as CVI, is a medical condition where veins struggle to effectively return blood to the heart. It primarily affects the leg veins, leading to blood pooling and increased pressure within these vessels.
Understanding CVI: The Basics
The circulatory system relies on veins to transport deoxygenated blood back to the heart. In the legs, this process faces the challenge of gravity, which healthy veins overcome through a combination of muscle action and specialized one-way valves. As leg muscles contract, particularly during movement like walking, they compress the veins, effectively pushing blood upwards toward the heart, acting as a “second heart” for venous return. Within the veins, small, pocket-like valves open to allow blood to flow upward and then close immediately to prevent it from flowing backward, ensuring a continuous, unidirectional flow.
Chronic venous insufficiency develops when these one-way valves become damaged or weakened, impairing their ability to close properly. This malfunction allows blood to flow backward, a phenomenon known as venous reflux, and accumulate in the lower extremities. The pooling blood then increases pressure within the veins, stretching their walls and further compromising valve function. This condition is progressive, meaning it can worsen over time if not managed.
What Causes CVI and Who is at Risk?
CVI often arises from previous damage to the vein valves, with deep vein thrombosis (DVT), or blood clots in the deep veins, being a frequent cause. Even after a blood clot dissolves, it can leave behind scar tissue that damages the delicate valves, hindering their proper function. Sometimes, CVI can be attributed to congenital factors, where individuals are born with malformed or absent vein valves. Vein wall weakness, leading to vein enlargement, can also prevent valves from closing completely.
Several factors can increase an individual’s likelihood of developing CVI:
Age is a contributing factor, with the condition becoming more common in adults over 50.
Being female also increases the risk, partly due to hormonal changes and the effects of pregnancy.
Excess body weight places additional pressure on leg veins, contributing to the development of CVI.
Prolonged periods of standing or sitting can also hinder proper blood flow and elevate venous pressure, making individuals in certain occupations more susceptible.
A family history of CVI or varicose veins also suggests a genetic predisposition.
Recognizing the Signs of CVI
The manifestations of CVI can vary, beginning with subtle indications and progressing to more noticeable changes. A common early sign is swelling, or edema, in the legs and ankles, which often worsens after prolonged standing or at the end of the day. Individuals may also experience an aching, heavy, or tired sensation in their legs, sometimes accompanied by cramping, particularly at night. This discomfort often improves with leg elevation.
Over time, changes to the skin on the legs and ankles may become apparent. This can include discoloration, often appearing as a reddish-brown hue due to blood leaking from capillaries. The skin may also become itchy, flaky, or develop a leathery texture, a condition known as stasis dermatitis. Visible, twisted veins, commonly referred to as varicose veins, are another frequent sign, though not everyone with varicose veins develops CVI. In more advanced stages, the skin may thicken and harden, a condition called lipodermatosclerosis, and open sores known as venous ulcers can form, typically near the ankles, which may be slow to heal.
Confirming and Addressing CVI
Diagnosis of CVI typically begins with a thorough physical examination, where a healthcare provider will visually inspect the legs for characteristic signs and inquire about symptoms and medical history. A key diagnostic tool is a duplex ultrasound, also known as a Doppler ultrasound. This non-invasive imaging test uses sound waves to visualize blood flow within the veins and assess the function of the valves, helping to identify areas of reflux or obstruction. The ultrasound allows medical professionals to determine the extent and location of valve damage.
Management of CVI aims to alleviate symptoms, prevent the condition from worsening, and improve an individual’s quality of life. Conservative measures are often the first approach. These include:
Wearing compression stockings, which apply graduated pressure to the legs to help blood return to the heart and reduce swelling.
Elevating the legs periodically throughout the day, especially above heart level, to reduce venous pressure and fluid accumulation.
Regular physical activity, particularly walking, to promote the calf muscle pump action, aiding blood circulation.
Maintaining a healthy weight and avoiding prolonged periods of standing or sitting.
When conservative measures are insufficient, various minimally invasive procedures may be considered. Endovenous thermal ablation, utilizing laser or radiofrequency energy, involves using heat to seal off damaged veins, redirecting blood flow through healthier vessels. Sclerotherapy involves injecting a solution into the affected veins, causing them to scar and close, after which the body gradually absorbs them. Phlebectomy is a procedure where damaged veins are physically removed through small incisions. These interventions are designed to address the underlying venous reflux and improve circulation in the affected limb.