Your heart needs care

What is coronary artery disease (CAD)?

Coronary artery disease (CAD) is a narrowing of the coronary arteries that supply the heart muscle with oxygen-rich blood. It is caused by deposits, known as plaques, made up of fats, calcium and connective tissue that accumulate in the vessel walls. These plaques reduce the diameter of the arteries and impede blood flow, limiting oxygen delivery to the heart muscle. This process is medically referred to as atherosclerosis.

Depending on its course, CAD can be acute, when a sudden vessel occlusion – often due to a blood clot – completely interrupts blood supply, or chronic, when a persistent narrowing reduces circulation. Both forms can lead to serious complications requiring prompt medical assessment and treatment.

How does coronary artery disease develop?

Coronary artery disease develops gradually from changes in the coronary arteries. It usually starts with damage to the inner lining of the vessel (endothelium), which can be caused by long-standing high blood pressure, elevated blood sugar or high LDL cholesterol. These microscopic injuries promote the deposition of various substances, such as cholesterol, other lipids, connective tissue, blood components, sugars and minerals like calcium phosphate, on the vessel wall. Over time these so-called plaques grow and narrow the vessel lumen, increasingly impeding blood flow.

Once narrowing reaches a certain degree, the affected coronary artery can no longer supply the heart muscle with sufficient oxygen and nutrients, impairing cardiac function during exertion. If a plaque ruptures, the body responds by forming a blood clot that can completely occlude the vessel. In that case blood flow is abruptly interrupted, causing a myocardial infarction – an acute, potentially life-threatening complication.

What are the symptoms of coronary artery disease?

Typical signs of coronary artery disease are primarily chest tightness and chest pain, referred to as angina pectoris. These complaints can present as pressure, stabbing or burning sensations and may radiate to the throat, neck, jaw, shoulders, arms or upper abdomen. Often additional symptoms such as shortness of breath, dizziness, nausea, sweating, inner restlessness or a strong sense of constriction up to fear of dying occur. Symptoms commonly worsen with physical or mental stress, in cold conditions or after heavy meals, but usually improve with rest or appropriate medication.

In chronic coronary syndrome the exertion threshold at which symptoms occur usually remains stable for a long time. Symptoms mainly appear when the heart's oxygen demand increases, for example during activity or stress, and subside quickly with rest.

The acute coronary syndrome, on the other hand, is characterised by sudden onset or markedly increased symptoms that can occur at rest or with minimal exertion. They last longer, respond less well to medication and are warning signs of an impending heart attack. Women and people with diabetes often experience these symptoms in atypical areas, for example between the shoulder blades, in the upper abdomen or on the right side of the body. Some individuals notice no symptoms for a long time, so the disease may only be discovered during an acute event.

What are the risk factors for coronary artery disease?

Several factors significantly increase the risk of coronary artery disease. These include smoking, as substances in tobacco damage blood vessels, promote deposit formation and encourage vessel narrowing. Obesity has a negative effect, especially if accompanied by elevated blood lipid levels that deposit on vessel walls and trigger inflammatory processes. Persistent high blood pressure adds strain to vessels and contributes to narrowing, while physical inactivity adversely affects both blood lipid levels and insulin sensitivity.

Diabetes mellitus – particularly if poorly controlled – damages vessel walls through chronically elevated blood sugar levels and accelerates arterial calcification. Aging increases risk in both sexes, often already in middle age for men and more markedly after menopause for women. Genetic predisposition and certain metabolic disorders, such as elevated homocysteine or fibrinogen levels, increase the likelihood of developing CAD. Unfavourable lipid profiles with high LDL and low HDL cholesterol as well as elevated triglycerides also promote vascular damage.

Psychosocial factors such as chronic stress or sleep deprivation also play a role, as they raise blood pressure and heart rate and enhance inflammatory processes. Until women reach menopause, men are on average at higher risk, partly attributed to hormonal protective mechanisms. The simultaneous presence of several of these factors substantially increases risk, making their combination particularly problematic.

How is coronary artery disease treated?

The aim of treatment for coronary artery disease is to improve blood supply to the heart muscle, reduce symptoms and prevent serious complications such as heart failure or myocardial infarction. Both medication and surgical procedures are used.

Treatment often starts with medication to reduce the heart's oxygen demand, dilate vessels and slow disease progression. Commonly prescribed agents include nitrates for rapid relief of acute symptoms, beta-blockers to lower heart rate and blood pressure, ACE inhibitors or AT1 blockers to reduce vascular resistance, statins to lower cholesterol and antiplatelet agents such as acetylsalicylic acid (aspirin) or clopidogrel to prevent clots. Diuretics may be used depending on the individual situation.

If these measures do not produce sufficient improvement or imaging shows a significant coronary narrowing, an interventional procedure is often recommended. This can involve placing a stent by cardiac catheterisation to keep the affected segment open, or performing a bypass operation to circumvent the narrowing using the patient's own vessel. The choice of procedure depends on the extent of narrowing, overall health and individual needs, and is usually decided by a multidisciplinary heart team.

Is coronary artery disease curable?

Current medical knowledge indicates that a complete elimination of coronary artery disease is not possible, as established vessel narrowings cannot be reversed. Treatment therefore focuses on slowing disease progression, relieving symptoms and preventing serious complications such as myocardial infarction. Depending on severity, medication, lifestyle changes and surgical procedures may be appropriate.

What you can do yourself against coronary artery disease: practical tips

• If you smoke, stop as soon as possible! Even a few cigarettes a day damage the coronary arteries and substantially increase the risk of heart attacks. Seek support if needed, for example medical advice, nicotine replacement products, specialised courses or apps. Expect setbacks, as quitting often succeeds only after several attempts.
• Make a Mediterranean-style diet your base: plenty of vegetables, some fruit, high-quality vegetable oils, fish and whole grains. This combination can have positive effects on your cholesterol, blood pressure and weight. Aim for at least three different vegetables per day and use extra virgin olive oil as your main fat source.
• Replace animal fats and hydrogenated vegetable fats with healthy oils. Olive oil is suitable for warm dishes, linseed or hemp oil for cold preparations. Avoid overheating rapeseed, sunflower or safflower oil, as harmful trans fats may form.
• Include fatty sea fish such as salmon, mackerel or herring in your diet regularly to provide omega-3 fatty acids. Two portions per week are optimal.
• Reduce consumption of sugar and highly processed foods to prevent blood sugar fluctuations, overweight and vascular damage. Pay particular attention to hidden sugars in drinks, for example in soft drinks, energy drinks or sweetened teas.
• Also watch your salt intake. Use as little salt as possible, as excess salt can raise blood pressure. Instead, use fresh herbs or spices such as turmeric, paprika or pepper.
• Build exercise firmly into your daily routine. Even 10 minutes of brisk walking at a stretch has measurable positive effects. Use small opportunities such as taking the stairs or walking at lunchtime.
• Perform targeted endurance training, ideally four to five times a week for 30 minutes each. Suitable activities include brisk walking, swimming, cycling or hiking. Gradually increase intensity and duration and aim for steady load.
• Have your individual training zone determined, for example via an exercise ECG, together with your doctor. Use a heart-rate watch if necessary to keep your heart rate in the recommended range.
• If you resume training after surgery or a myocardial infarction, start early but under medical supervision. Begin with light, short sessions and increase load only gradually.
• Take typical warning signs such as chest pain, tightness or palpitations seriously and seek timely medical assessment. Especially in older patients a coronary artery may be narrowed and quickly lead to serious heart disease.

Living with coronary artery disease requires a conscious, long-term commitment to heart health. Timely measures can ease symptoms and prevent life-threatening events.