What is Peripheral Vascular Disease?
Peripheral Vascular Disease (PVD) is a term that includes both Peripheral Arterial Disease (PAD) and venous disease. PAD is caused by the build-up of fatty deposits (or atherosclerosis) in the arteries, which can partially or totally block the blood flow. This disease most commonly affects the arteries in the stomach (abdominal aorta), the pelvis (iliac arteries), and the legs, but it can also occasionally impact the arms.
Almost 200 million people worldwide suffer from PAD, and the number is increasing due to longer lifespans and prolonged exposure to risk factors. Symptoms and progression of PAD can vary widely among patients. Some people may not experience any symptoms, while others might suffer from ulcers on the skin due to decreased blood supply (arterial ulceration), muscle pain due to poor blood circulation (claudication), lack of blood supply to the limbs even at rest (resting limb ischemia), or even loss of a limb.
PAD is considered a cardiovascular disease equivalent because it is linked to a high risk of serious and sometimes deadly events, such as heart attack (myocardial infarction) and stroke. As a progressing and debilitating disease that affects the whole body (a systemic disease), treating PAD often involves a team of healthcare professionals working together to improve the patient’s health outcomes.
3rd digit secondary to PAD.
What Causes Peripheral Vascular Disease?
Peripheral vascular disease (PVD) is mainly caused by the buildup of fatty deposits in the arteries, a condition known as atherosclerosis. This buildup can reduce the blood flow to vital organs leading to organ damage due to insufficient oxygen and nutrients, a condition known medically as end-organ ischemia.
Atherosclerosis is a complex condition involving many different types of cells, proteins, and body functions. Several risk factors can speed up this process. Some of these risk factors are things you can’t change (non-modifiable), and others are things you can take steps to control (modifiable).
The risk factors for peripheral vascular disease include:
* Using tobacco
* Having diabetes
* High blood pressure
* HIV infection
* High cholesterol levels
* Being older than 50 years
* High homocysteine levels, which is a type of amino acid related to heart disease
* Body Mass Index (BMI) over 30, indicating obesity
* Having a family history of heart and blood vessel diseases
Out of the risk factors listed above, smoking is linked to the highest risk of developing PVD. Research suggests that smokers are nearly three times more likely to develop PVD (odds ratio 2.7). A history of heart and blood vessel diseases and diabetes are also significant risk factors. People with these conditions are more than twice as likely to develop PVD.
Risk Factors and Frequency for Peripheral Vascular Disease
Peripheral vascular disease, or PAD, affects about 200 million people globally, including around 40 to 45 million people in the United States. This disease is less common in younger people, but the incidence rate significantly increases in people over the age of 80, with more than 20% experiencing PAD.
There have been conflicting reports about the difference in occurrence between men and women. Some studies, like the Framingham and Rotterdam studies, found that intermittent claudication (a condition caused by PAD) was more common in men. However, other studies found that when diagnosing PAD based on the ankle-brachial pressure index (ABI), there were more women diagnosed with the disease or there was no significant gender divide.
The discrepancy in the diagnosis methods might be because women often show atypical symptoms and have lower ABI values naturally. As such, they are typically observed later than men.
- Peripheral vascular disease affects about 200 million people worldwide, including around 40 to 45 million in the US.
- The disease is more common in older populations. Over 20% of people over 80 have PAD.
- There are conflicting reports on how PAD affects men and women. Some studies found it more common in men while others found no significant difference.
- Women might be diagnosed later due to atypical symptoms and naturally lower ABI values.
Furthermore, disparities can be seen in different racial and socioeconomic groups. African Americans, for example, are found to be more likely to have PAD than non-Hispanic whites. Similarly, people in lower economic status or with less education are more prone to having PAD.
- There is racial and economic disparity in PAD occurrence. African Americans are more likely to have PAD.
- People with lower socioeconomic status or less education are more prone to PAD.
Signs and Symptoms of Peripheral Vascular Disease
Peripheral vascular disease (PAD) can be tricky to diagnose since other related health conditions can mirror its symptoms. Moreover, many patients may not show any symptoms or their symptoms may not be typical. The severity of blocked arteries and the presence of additional health conditions can also influence how the disease manifests in each patient. The symptoms can be different especially when patients also have back issues, spinal canal narrowing, or severe diabetes, all of which can affect how they perceive pain.
The atypical pain experienced can be constant, unrelated to physical activity, or persist for longer than ten minutes after exercising. ‘Pseudo claudication’ (neuropathic pain seen in cases of spinal canal narrowing) differs from PAD and can be identified with a detailed examination and health history. This type of pain characterizes weakness and numbness, unaffected by the degree of physical effort, and its relief more likely to come from things like changing body posture or sitting down than resting.
Even though PAD could lead to serious circulatory issues, patients could still be symptomless. In fact, over 50% of patients with PAD don’t exhibit any symptoms. This asymptomatic presentation of PAD could be due to older people misunderstanding their symptoms as part of the normal aging process. Additionally, patients with mild PAD might not exercise enough to create a significant imbalance between oxygen supply and demand, causing them to remain symptomless.
‘Intermittent claudication’, recognized as a classic sign of PAD, is described as a cramping sensation during exercise, accompanied by fatigue, weakness, or pressure. Symptoms can be intensified when the leg is raised and relieved when the leg is hanging down. It may also present with numbness, weakness, stiffness, or coldness of the lower extremity. The level of key blockage typically occurs one level beyond the area in which discomfort is felt. For example, if the hindrance is in the aortoiliac region, the patient will experience discomfort in the thigh and buttock area.
Few existing patients may progress to having unbearable pain at rest (critical limb ischemia), unhealing wounds or sores, and gangrene which can lead to potential limb amputation. During physical examination, the doctor typically looks for specific markers like signs of cigarette smoking, previous vascular surgery scars, or amputations. They also assess the pulse to check its rate, rhythm, and strength, and test for pulmonary disease. Additionally, a neurological examination is necessary to identify pseudo claudication. The limbs are inspected for signs like loss of pulse, abnormal skin color, muscle atrophy, cold or blue skin, or pain upon touch. Arterial leg ulcers may be tender, with irregular edges, dry base, and light-colored or dead tissue at the center.
Testing for Peripheral Vascular Disease
The diagnosis of peripheral vascular disease (PAD), a circulation condition that causes narrowed or blocked blood vessels, usually depends on the patient’s risk factors, symptoms, and physical examination results. Risk factors include smoking, diabetes, high blood pressure, high cholesterol, and obesity. Symptoms related to PAD can be similar to those of other conditions affecting the nervous system, muscles, or blood vessels, so it’s important to distinguish PAD correctly.
During a physical exam, doctors might notice cool skin that appears shiny, weakened or missing pulses, slow capillary refill time (the time taken for color to return after pressure is applied), pallor when the leg is lifted, a red color that appears when the leg is lowered, and unusual sounds (called bruits) in major blood vessels through a stethoscope. Severe cases of PAD often show non-healing sores or gangrene.
A commonly used, cost-effective method to diagnose PAD is a test called the ankle-brachial index (ABI), which measures blood pressure at the ankle and in the arm to see if these are in their normal ratio. It involves inflating a blood pressure cuff around your ankle until the blood flow stops, monitored by a Doppler ultrasound device, then slowly deflating the cuff and noticing when the blood flow returns. This test is carried out on both legs, then divided by the highest blood pressure measured in the arm. Most people have an ABI ratio from 0.9 to 1.2 – anything less than 0.9 could mean PAD. However, in people with diabetes or advanced kidney disease, the vessels may not compress normally, and this can lead to inaccurately high results.
Duplex ultrasonography, another safe and cost-effective test, can determine the location, severity and length of the narrowed or blocked segments in your blood vessels. This type of ultrasound combines traditional ultrasound with Doppler ultrasound and is useful for monitoring the disease progress and planning further treatment.
If more detailed images of your blood vessels are needed, your doctor might recommend magnetic resonance angiography (MRA) or computed tomography angiography (CTA). MRA is particularly useful for revealing tiny vessels that may not be seen with other imaging methods. CTA offers similar diagnostic accuracy to MRA, and both can help to decide on the right treatment method – whether bypass surgery or angioplasty.
Treatment Options for Peripheral Vascular Disease
If you’ve been diagnosed with peripheral vascular disease, your treatment approach needs to be customized based on your age, risk factors, how severe your disease is, and your overall health. The main goals of treatment are reducing the risk of heart attacks and other cardiovascular events, and improving any symptoms you may have. This is important because people with peripheral vascular disease often die from heart disease.
The first step in managing peripheral vascular disease is lifestyle changes to help slow down the disease. Doctors may also prescribe medications or suggest procedures to help manage symptoms and lower the risk of heart disease.
The first thing you can do to lower your risk of heart disease is to tackle any lifestyle issues that might be causing problems. If you smoke, quitting will be a big help. Smoking increases damage to your arteries and increases your risk of heart disease. To help you quit, you might need counseling or treatments like nicotine replacement therapy or medications to ease cravings. If you have high cholesterol, your doctor might recommend statin medications, which have been shown to reduce heart disease risk and deaths in people with peripheral vascular disease. Don’t forget to keep a check on your blood pressure too – if you have diabetes, it should be below 130/80; if you don’t, it should be below 140/90. Diabetes also makes peripheral vascular disease worse, so it’s important to keep your blood sugar levels under control. The ideal target for most people is a hemoglobin A1c level of less than 7%.
Exercise can also help alleviate symptoms of peripheral vascular disease. Research has shown that supervised exercise programs can help people with the disease walk further without pain. The program usually includes 30 to 45 minutes of exercise, four to five times per week, for three months. However, these programs have not been shown to increase lifespan.
If lifestyle changes and exercise aren’t enough to manage your symptoms, your doctor might recommend medication. The two most common drugs prescribed are cilostazol and naftidrofuryl. Both of these drugs can relieve symptoms and improve your ability to walk. They work in slightly different ways, and naftidrofuryl has fewer side effects, so you might need to try both to find one that works for you.
For most people with peripheral vascular disease, it’s also a good idea to take a daily aspirin to help lower the risk of heart disease, but there’s no agreement about the best dose.
If even exercise and medication aren’t enough to manage your disease, you might need a procedure to reopen or bypass your blocked arteries. These procedures are usually reserved for people with very serious symptoms, like pain even when at rest, skin ulcers, and gangrene. The decision about the best way to do this depends on lots of factors, so your care team might include a number of different types of doctors, like vascular surgeons, to help make the right decision for you.
What else can Peripheral Vascular Disease be?
When a patient shows certain signs and symptoms, doctors need to consider a range of possible explanations. Here are some of the key ones they might think of:
Neurological issues, which may include:
- Nerve root compression
- Spinal stenosis
- Peripheral neuropathy (problems with the nerves outside the brain and spinal cord)
- Nerve entrapment (when a nerve is squeezed)
Musculoskeletal problems, such as:
- Medial tibial stress syndrome (also known as ‘shin splints’)
- Osteoarthritis (a type of joint disease)
- Muscle strain
- Baker cyst (a fluid-filled cyst that causes a bulge at the back of the knee)
Vascular diseases, for example:
- Chronic venous insufficiency (when the leg veins struggle to send blood back to the heart)
- Thrombophlebitis (a condition where a blood clot blocks one or more of your veins)
- Deep venous thrombosis (a serious condition where a clot forms in a vein)
- Raynaud phenomenon (where small blood vessels in hands or toes constrict)
- Thromboangiitis obliterans (a rare disease that causes clots in small and medium-sized vessels)
What to expect with Peripheral Vascular Disease
The overall outlook for patients with peripheral vascular disease, which is a condition involving poor blood flow to the arms and legs, depends on several factors. These factors include the patient’s other health risks, their heart health, and the severity of their disease.
Looking at the condition of the limb at the 5-year mark, nearly 80% of patients will have stable issues with claudication – a condition where you experience muscle pain, aching, or fatigue when you walk. Only 1% to 2% of patients will develop critical limb ischemia – a severe obstruction of the arteries which drastically reduces blood flow to the extremities, in 5 years.
About 20 to 30% of patients with PAD (Peripheral Arterial Disease) will unfortunately pass away within 5 years, and 75% of these deaths are linked to cardiovascular causes.
Possible Complications When Diagnosed with Peripheral Vascular Disease
Peripheral vascular disease impacts many different body systems and can potentially lead to several complications:
- An urgent health condition caused by reduced blood flow to the heart, often referred to as acute coronary syndrome
- Stroke, a condition where the blood supply to the brain is disturbed
- Nonhealing ulcer, a sore that does not heal as it should
- Gangrene, a severe and potentially life-threatening condition where body tissue dies
- Amputation, or the removal of a body extremity by trauma, prolonged constriction, or surgery
- Deep vein thrombosis, a condition where a blood clot forms in a deep vein, often in your leg
- Erectile dysfunction, a common health issue in men where they have difficulty achieving or maintaining an erection
Preventing Peripheral Vascular Disease
Treating a patient to achieve the best possible results usually involves a well-rounded approach. This combines lifestyle changes that don’t involve medication, along with treatments involving drugs. Here’s a brief explanation of what that might look like:
Quitting smoking is a start, as it helps improve overall health. Keeping a regular check on blood pressure levels outside of a clinical setting, or ambulatory blood pressure monitoring, can help track fluctuations and manage blood pressure better.
Following the prescribed exercise and medication regimen without fail is crucial for the treatment to work effectively. It’s equally important to manage cholesterol levels, which can be done by adopting a healthy diet and taking prescribed medications such as statins. Statins are a type of drug that helps lower your body’s cholesterol level.
Losing weight if you’re overweight can have significant health advantages as well. For patients with diabetes, maintaining the HbA1c level under 7% is vital. HbA1c is a test that measures the average level of blood sugar over the past 2 to 3 months. It is essential to note that the percentage can be higher, depending on other health conditions or risk of low blood sugar levels.
Last but not least, regular follow-up visits with a team of healthcare professionals are integral to a fully-rounded healthcare plan. This ensures that the treatment is working, and any needed adjustments can be made promptly.
