The heart is the first organ to start its function as the embryo is formed inside the mother’s womb. It continues to perform its functions tirelessly until its end. It beats nearly 275 crores times, on average, for an individual with a lifespan of 75 years. In this journey of tireless work, oxygen and nutrients are needed for it to execute its functions, which are provided by the blood carried by the three blood vessels of the heart itself. They are the left anterior descending artery, left circumflex artery and right coronary artery. Due to various modifiable and non-modifiable risk factors, these blood vessels get clogged by cholesterol-based materials, leading to pathway blockages.
What happens when the pathways (coronary arteries) that carry this blood become hard, narrowed, and inflexible? This condition, known as calcified coronary artery disease, is a growing concern worldwide. In rare cases, such calcified diseases (nodular calcium) can trigger heart attacks too. Most of us have heard of blocked arteries due to cholesterol; however, few know about such calcium deposits that can form in the artery walls. Even with modern medical tools, these calcium deposits make blockages stiff and challenging to treat.
In this article, we will discuss calcified coronary artery disease, why it happens, how common it is, the possible symptoms it can create and how it can be treated, to help you understand your heart better.
What are coronary arteries and why do they calcify?
Coronary arteries are the lifeline tubes or the blood vessels that run on the surface of the heart and carry oxygen-rich blood to the heart muscles. Healthy arteries are smooth, elastic, and flexible. However, over time, due to various risk factors like age, being of the male sex, genetics, diabetes, high blood pressure, smoking, cholesterol levels, reduced physical activity and poor eating habits, fatty deposits, known as plaques begin accumulating inside these tubes or blood vessels. This process is called atherosclerosis in medical terms. Over the years, such plaques harden themselves into calcium, similar to that seen in our bones, converting our soft, jogging-friendly cushioned road (elastic blood vessels) into a hard, rough mountain road. This process leads to the formation of calcified coronary artery disease (cCAD). To a certain extent, such calcified coronary vessels are not dangerous as they do not lead to heart attacks frequently as compared to non-calcified, fat-rich blockages; however, one form of calcified CAD, known as nodular calcium, in which the calcium protrudes into the lumen and touches the blood, is a proven risk factor for heart attacks.
Risk factors for CAD and calcified CAD
There are several risk factors for CAD: elderly individuals are at a higher risk; factors such as having diabetes mellitus, high cholesterol levels and high blood pressure (hypertension) also contribute to the risk. Other risk factors include chronic kidney disease, smoking, having a family history of heart disease, and sedentary lifestyles and unhealthy diets.
When does the soft plaque change into hard plaque? The reason for this is still not fully known; what is known is that it takes years for the plaque to harden.
How common is calcified CAD?
Calcified CAD can be identified through various modalities such as conventional coronary angiograms, intra-vascular ultrasound (IVUS), optical coherence tomography (OCT) and computer tomography (CT). CT-based calcium scoring for coronary artery diseases is often called coronary artery calcium (CAC). This CAC score is often used in clinical practice to identify calcified diseases. Though the presence of CAC proves CAD, the absence of CAC does not rule out CAD, especially in young patients.
The prevalence of the disease varies based on the modality used to identify the calcium. In general, nearly 20-25% of CAD cases are diagnosed to have CAC by coronary angiograms, while this number rises to nearly 65% using IVUS.
Why is it important know the about presence of calcium?
Identifying calcified CAD is very important in asymptomatic patients who need treatment for the same, either using bypass surgery or angioplasty (stenting). The grafting site for bypass should ideally be calcium-free for better short-term and long-term results. It is very important in angioplasty also. Imagine trying to open a metal pipe with a balloon inside: it is very hard and cannot be opened, and this is what it is like for calcified CAD. Such hard blockages are difficult to open by conventional balloon angioplasties without dedicated tools, leading to stent under-expansion, which might result in poorer short-term and long-term outcomes. The chances of potential adverse events during angioplasties are higher with calcified CAD. In short, calcified coronary disease is tougher to treat and riskier to ignore.
How does this disease present?
The symptoms are the same as any other CAD. Usually, it causes exertional chest pain, breathing problems, fatigue, palpitations and rarely, a heart attack. In case, you have any of the above symptoms, please consult your doctor.
How can it be prevented?
The best way to prevent Calcified CAD is to prevent CAD itself. The most important culprit for CAD is bad cholesterol (LDL). Keeping it low for a long time is a proven strategy for reducing CAD. The bad cholesterol burden is depicted in medical terms as ‘LDL-C-years’ similar to pack-years of smoking. In addition to this, all the risk factors described above should be kept under control.
Dedicated tools to treat calcified CAD
Patients who have exertional symptoms, despite lifestyle modifications and drugs, may be appropriate candidates for complex procedures to handle calcified CAD. The most commonly-used tool to handle such calcified CAD is rotablation (RA), where a small diamond-coated burr is rotated at a rapid speed to break the calcium as an adjunctive device, following which standard devices like stents can be deployed and expanded well, using conventional balloons. Orbital atherectomy is a near-similar technology that could also treat such calcified blocks. Balloon-based technologies like cutting balloons, scoring balloons, super-high pressure OPN balloons, and intravascular lithotripsy (IVL) are also becoming common. IVL is the newest technology, where sound waves are used to crack open the calcium, similar to how kidney stones break. The safe and effective use of such therapies has provided excellent long-term prognoses in such patients.
Healthy lifestyles are crucial
Calcified coronary blocks are not problems that we face in the elderly alone, unlike in the Western population. Patients present to us with exertional chest pain or breathlessness. Rarely, it can lead to heart attacks. On a positive note, many patients with such heavily calcified arteries live long and healthy lives after treatment, especially when combined with lifestyle changes and regular follow-ups. Putting your mind towards mindful eating with good exercise and controlling proven risk factors are the pillars of a healthy life.
(Dr. S. Nagendra Boopathy is a specialist in complex coronary and percutaneous valve therapies, and professor of cardiology and senior consultant interventional cardiologist, Sri Ramachandra Institute of Higher Education and Research, Chennai. [email protected])
Published – June 02, 2025 02:24 pm IST