Vascular Calcification

Vascular calcification is mineral deposits building up in the walls of your blood vessels, making them stiff and hard. While once thought to be a natural part of aging, scientists now understand it as an active disease process that significantly increases your risk of heart attack, stroke, and other serious health problems.

Table of contents

• What is vascular calcification?
• Types of vascular calcification
• Who is affected?
• Risk factors
• Symptoms and complications
• How is it diagnosed?
• Treatment options
• Prevention

What is vascular calcification?

Vascular calcification is the buildup of calcium deposits in the walls of your arteries and veins^[1]. These mineral deposits sometimes stick to fatty deposits, or plaques (buildups of fat and cholesterol), that are already present on the walls of blood vessels^[1].

For many decades, vascular calcification was simply considered a consequence of aging. However, studies now confirm that it is an actively regulated process that shares many features with bone development and metabolism^[2]. The calcium forms hard crystals in the blood vessel wall. Laboratory studies have shown that calcium deposits in arteries form because the muscle cells in the blood vessel wall start to change into bone-like cells when they are old or diseased^[5].

When calcium accumulates in your arteries, it creates complex, bone-like substances that reduce arterial flexibility^[18]. This hardening makes it more difficult for your heart to pump blood efficiently throughout your body. The condition is sometimes called “hardening of the arteries”^[5].

Types of vascular calcification

Calcification of the vessel wall occurs in two different layers of the artery, and each type has different causes and health risks^[2].

Intimal calcification occurs in the innermost layer of the vessel wall. This type is associated with atherosclerosis (a disease where plaque builds up inside arteries)^[2]. In atherosclerosis, the intima becomes greatly inflamed and thickened, and calcification occurs^[2]. This type is more common in coronary arteries and is associated with blocked arteries and blood clots^[1][3].

Medial calcification, also known as Mönckeberg sclerosis, affects the middle layer of arteries. It is more prevalent in arteries below the abdomen and in the lower extremities^[12]. This type is a non-obstructive process that leads to increased vascular stiffness and reduced vascular compliance^[2]. The distribution of medial calcification extends continuously throughout the vascular bed, resulting in arterial stiffening and decreased compliance^[12].

Medial calcifications are most often associated with kidney disease, diabetes, high blood pressure, and advanced age^[1].

Vascular calcification can also be found in the valves of the heart. Calcification of the leaflets can change the mechanical properties of the tissue and result in stenosis (narrowing)^[2].

Who is affected?

Vascular calcification is highly associated with cardiovascular disease mortality, particularly in high-risk patients with diabetes and chronic kidney diseases^[2]. Studies show that more than 60% of people over 60 have at least some signs of this condition^[6].

In people older than 70, more than 90% of men and 67% of women have coronary artery calcification^[3]. Before menopause, estrogen protects women from developing atherosclerosis. This is why women tend to develop atherosclerosis 10 to 15 years later than men^[3].

Vascular calcification affects a wide variety of patients. In patients with kidney failure undergoing hemodialysis (a treatment that filters waste from blood when kidneys fail), vascular calcification is a frequent complication, with time on hemodialysis associated with more severe calcification^[2].

A rare and severe form called calcific uremic arteriolopathy or calciphylaxis is another complication of hemodialysis. In this condition, small arteries calcify, leading to death of skin tissue and ulceration. This condition has a mortality rate of over 50% at 2 years^[2].

Risk factors

You’re more likely to develop vascular calcification if you have certain health conditions or lifestyle factors.

The major risk factors include^[3][6]:

• Chronic kidney disease
• Glucose issues such as diabetes mellitus (a condition where your body cannot properly control blood sugar levels)
• Too much bad cholesterol (low-density lipoprotein or LDL) and too little good cholesterol (high-density lipoprotein or HDL)
• High BMI (body mass index)
• Family history of coronary artery calcification
• High blood pressure
• A history of cigarette smoking or using other tobacco products
• Older age
• High phosphate levels
• High calcium level

Postmenopausal women with osteoporosis (a condition that weakens bones) and people with type 1 or type 2 diabetes or metabolic syndrome are at greater risk of developing vascular calcifications^[1]. Men also have a higher risk for coronary artery calcification^[3].

People who are white are more likely than other races to have coronary artery calcification^[3].

Symptoms and complications

People with vascular calcification often don’t have any symptoms, especially in the early stages^[3][1]. You may not always notice symptoms of vascular calcification until it causes arteries to harden and the heart has to work harder to pump blood^[1].

Over time, people may develop symptoms such as^[3]:

• Stable angina (chest pain or discomfort)
• Shortness of breath
• Heart attack

Eventually, you might develop symptoms of peripheral artery disease (PAD), a condition affecting blood vessels outside the heart. The most common PAD symptom is pain or cramping in your leg muscles when walking or climbing stairs^[1].

If plaque is dislodged, it can cause a stroke. Symptoms of a stroke include sudden weakness, confusion, or dizziness, along with vision and speech impairment^[1].

Vascular calcifications can raise the risk of^[1]:

• Heart attack
• Stroke
• Dementia
• Renal insufficiency (reduced kidney function)
• Inadequate blood supply to arms and legs

Coronary artery calcification makes your arteries stiff and less able to expand and contract. This puts you at a higher risk for cardiovascular issues and causes less blood to get to your heart muscle^[3].

How is it diagnosed?

When your doctor tells you that you have calcified arteries, it is usually after you have had a coronary calcification scan. This is a type of X-ray that can show how much calcium has built up in the blood vessels of your heart^[5]. This is important because how much calcium you have in your arteries is one of the strongest indicators for your risk of having a heart attack in the future^[5].

The amount of calcification you have is an indicator of how bad your atherosclerosis may be^[3]. Knowing this helps doctors decide the best course of treatment for you^[5].

Several diagnostic tests can identify vascular calcification^[12]:

Extravascular ultrasound (EVUS) can noninvasively identify the extent and location of calcific lesions, but the shadowing of the lumen by calcium may limit the ability to determine blood flow velocities in the underlying vessel^[12].

CTA (computed tomography angiography) identifies calcium very well when used as an additional noninvasive diagnostic test. However, extensive vascular calcification decreases the diagnostic accuracy of CTA because it creates a “blooming artifact,” which can make the lesion appear more severe^[12].

Diagnostic angiography is the standard invasive diagnostic tool, but it can underestimate the calcium burden because most angiography is taken in only one imaging plane and will miss calcium viewed from other angles^[12].

The process of calcium buildup can start in your 20s, but your healthcare provider may not see it until there’s an amount large enough to show up on imaging^[3].

Treatment options

The goal in treating vascular calcification is to slow (and possibly reverse) its progression and prevent serious consequences such as heart attack or stroke^[10]. There is no cure, but controlling risk factors can help limit calcification and prevent life-threatening disease^[6].

Lifestyle changes

Changes to your lifestyle can help prevent and slow the progression of vascular calcification. These can include^[10][6]:

• Eating a healthy diet (especially to limit cholesterol, fat, and sodium)
• Exercising regularly
• Quitting smoking
• Avoiding alcohol
• Losing weight
• Managing chronic conditions like diabetes and high blood pressure

Medications

If you’re at risk of vascular calcification, your doctor may prescribe cholesterol medications to reduce LDL, known as the “bad” cholesterol (such as statins), or to increase HDL, known as the “good” cholesterol (such as niacin)^[10]. Newer medications such as PCSK 9 inhibitors are given by injection and can help lower cholesterol in more difficult instances^[10].

Other medications may be prescribed to reduce blood pressure (such as beta blockers, ACE inhibitors, diuretics), control blood sugar (anti-diabetic medications), prevent clots (such as aspirin), or dissolve a blood clot that has already formed (such as warfarin)^[10].

Current therapy is closely linked to strategies for preventing disordered bone and mineral metabolism in advanced kidney disease and involves lowering the circulating levels of both phosphate and calcium^[9].

Procedures and surgery

For severe atherosclerosis (plaque) that has caused or threatens to cause symptoms or disease, further intervention may be necessary^[10].

Coronary stenting is a minimally invasive procedure that uses a thin, flexible tube called a catheter that is guided into the blocked artery. A tiny balloon is inflated to pry open the plaque and restore blood flow. A stent (small mesh tube) is inserted to keep the artery wide open^[10].

Bypass surgery is a common approach that surgeons use to create new routes through which blood can flow around blocked or narrowed arteries. These “bypasses” are created using healthy vessels taken from the chest, arms, or legs^[10].

Calcification makes it difficult for your healthcare provider to do percutaneous coronary intervention (PCI) or angioplasty. It makes it harder to expand a stent to keep your artery open^[3].

Prevention

While some risk factors such as age cannot be modified, many others can be managed through lifestyle changes and medical interventions^[18]. Recognizing the early signs and addressing contributing factors can help you maintain healthier arteries and reduce cardiovascular risk.

Eating a healthy diet, exercising regularly, maintaining a healthy weight, and managing chronic conditions like diabetes and high blood pressure are key to preventing or slowing down vascular calcification^[6].

After age 40, calcium from your bloodstream can settle in parts of your body. Damaged, inflamed, or repaired arteries are more likely to attract calcium deposits^[3].

The calcium deposits in your arteries are not related to how much calcium you eat^[5]. In the body, calcification is actually part of the aging process. Calcifications accumulate in the vessels, heart, or valves as calcium travels through the bloodstream^[1].