What is a unstable angina?

Angina, a condition characterised by chest pain or discomfort, is a common and often overlooked symptom of underlying heart disease. While stable angina is the more common form, unstable angina presents a more serious and unpredictable challenge. Here, we’ll take a closer look into unstable angina, exploring its causes, symptoms, diagnosis and treatment.

Understanding unstable angina

Unstable angina is a type of chest pain that occurs when the heart muscle doesn’t receive enough oxygen-rich blood. This is typically caused by a blockage or narrowing in the coronary arteries, the vessels responsible for supplying blood to the heart. Unlike stable angina, which has a predictable pattern and is often triggered by physical exertion, unstable angina can strike without warning, even at rest or during sleep.

What sets unstable angina apart?

The key distinguishing factor between stable and unstable angina is the unpredictable nature of the latter. Unstable angina episodes can last longer, occur more frequently, and may not be relieved by rest or medication. This unpredictability is a clear indication that the underlying condition is worsening and the risk of a heart attack is significantly elevated.

Recognising the symptoms

Chest pain or discomfort is the hallmark symptom of unstable angina, but it can manifest in various ways. Patients may experience a tight, heavy, or burning sensation in the chest, radiating to the arms, neck, jaw, or back. Other common symptoms include shortness of breath, sweating, nausea, and dizziness. It’s important to recognise these warning signs and seek immediate medical attention, as unstable angina can quickly progress to a life-threatening heart attack.

Causes and risk factors

Coronary artery disease, the leading cause of unstable angina, is characterised by the buildup of fatty deposits within the coronary arteries. This narrowing of the arteries, known as atherosclerosis, can impede blood flow to the heart muscle, triggering episodes of unstable angina.

Atherosclerosis and plaque buildup

The formation of plaque in the coronary arteries is a gradual process that can take years or even decades to develop. As the plaque accumulates, it can rupture, forming a blood clot that further obstructs the artery. This sudden blockage is a common trigger for unstable angina and can significantly increase the risk of a heart attack.

Risk factors for unstable angina

Certain factors can increase an individual’s likelihood of developing unstable angina. These include:

• Advancing age
• Family history of coronary artery disease
• Smoking
• Diabetes
• High blood pressure
• High cholesterol levels
• Obesity
• Sedentary lifestyle
• Emotional stress

Recognising and addressing these risk factors through lifestyle modifications and medical interventions can play a key role in preventing the onset of unstable angina and reducing the risk of more severe cardiovascular events.

Diagnosing unstable angina

Diagnosing unstable angina requires a comprehensive evaluation by a healthcare professional. The process typically involves a combination of various tests and examinations.

Initial assessment

During the initial assessment, your healthcare provider will conduct a physical examination, take your medical history, and ask about your symptoms. They may also perform an electrocardiogram (ECG) to assess the electrical activity of your heart and identify any abnormalities.

Cardiac biomarkers

Cardiac biomarkers, such as troponin and creatine kinase-MB (CK-MB), are blood tests that can help distinguish unstable angina from a heart attack. These markers indicate the presence of heart muscle damage, a key difference between the two conditions.

Imaging tests

To further evaluate the extent and severity of the coronary artery disease, your healthcare provider may order imaging tests, such as:

• Stress testing: This involves monitoring your heart’s activity while you exercise or take medication to simulate physical exertion
• Coronary angiography: This procedure uses a dye and X-ray imaging to visualise the inside of your coronary arteries to identify any blockages or narrowing
• Echocardiography: This non-invasive imaging technique uses sound waves to create a detailed picture of your heart’s structure and function

By combining these diagnostic tools, your healthcare team can accurately identify the underlying cause of your chest pain to develop an appropriate treatment plan.

Treatment strategies for unstable angina

The primary goal of unstable angina treatment is to restore adequate blood flow to the heart, relieve symptoms, and prevent the progression of a heart attack. Treatment typically involves a combination of medications and, in some cases, invasive procedures.

Medication management

The initial management of unstable angina often involves the use of various medications, including:

• Nitroglycerin: This medication helps dilate blood vessels, improving blood flow to the heart
• Antiplatelet agents: Drugs like aspirin and clopidogrel help prevent the formation of blood clots
• Beta-blockers: These medications reduce the heart’s workload and lower blood pressure
• Statins: Cholesterol-lowering drugs can help slow the progression of coronary artery disease
• Angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs): These medications help manage high blood pressure and protect the heart

Your healthcare provider will tailor the medication regimen to your specific needs and monitor its effectiveness over time.

Invasive procedures

In some cases, when medications alone are not sufficient, your healthcare provider may recommend an invasive procedure to improve blood flow to the heart. These interventions include:

• Percutaneous Coronary Intervention (PCI): Also known as angioplasty, this procedure involves the use of a small balloon to widen the narrowed or blocked coronary artery, often followed by the placement of a stent to keep the artery open
• Coronary Artery Bypass Grafting (CABG): This surgical procedure involves creating a new pathway for blood to flow around the blocked or narrowed coronary artery, using a blood vessel from another part of the body
• The choice between these procedures will depend on the extent and location of the coronary artery disease, as well as your overall health and medical history.

Prevention

Once the immediate treatment for unstable angina has been addressed, the focus shifts to preventing the recurrence of symptoms and reducing the risk of future cardiovascular events.

Lifestyle modifications

Adopting a healthy lifestyle is crucial in managing unstable angina and reducing the risk of complications. Recommended lifestyle changes include:

• Quitting smoking
• Maintaining a balanced, heart-healthy diet
• Engaging in regular physical activity
• Achieving and maintaining a healthy weight
• Managing stress and practicing relaxation techniques

These lifestyle modifications, combined with ongoing medical treatment, can significantly improve outcomes and quality of life for individuals with unstable angina.

Follow-up

Regular follow-up appointments with your healthcare provider are essential for monitoring your condition and adjusting your treatment plan as needed. This may include periodic stress tests, imaging studies, and blood tests to assess the effectiveness of your treatment and detect any changes in your heart health.

Outlook

The outlook for individuals with unstable angina largely depends on the severity of the underlying coronary artery disease, the effectiveness of the treatment, and the individual’s adherence to the recommended lifestyle changes.

Short-term outlook

With prompt and appropriate treatment, the immediate outlook for individuals with unstable angina is generally favourable. However, the risk of a heart attack remains high, and close monitoring is important during this critical period.

Long-term outlook

In the long term, the outlook for individuals with unstable angina can vary. Those who respond well to treatment, make necessary lifestyle changes, and maintain regular follow-up care often have a better outlook and a lower risk of recurrent episodes or more severe cardiovascular events. Ongoing management and adherence to the prescribed treatment plan are key to improving long-term outcomes.

Coping and living with unstable angina

Living with unstable angina can be challenging, both physically and emotionally. However, with the right support and strategies, individuals can manage their condition and maintain a good quality of life.

Emotional support

Dealing with the unpredictability and potential severity of unstable angina can be stressful and cause anxiety. Seeking emotional support from family, friends, or mental health professionals can help individuals cope with the psychological aspects of the condition.

Lifestyle adjustments

In addition to the recommended lifestyle changes, individuals with unstable angina may need to make adjustments to their daily routines and activities to accommodate their condition. This may include:

• Pacing physical activities and avoiding overexertion
• Identifying and avoiding known triggers for angina episodes
• Keeping nitroglycerin or other angina medications readily available
• Communicating with employers and loved ones about the condition and its management

Communication with healthcare providers

Maintaining open and frequent communication with your healthcare team is important. Reporting any changes in symptoms, side effects of medications, or concerns about your condition can help your providers optimise your treatment plan and ensure the best possible outcomes.

Conclusion

Unstable angina is a serious and potentially life-threatening condition that requires quick medical attention and comprehensive management. By understanding the underlying causes, recognising the symptoms, and following the recommended treatment and lifestyle strategies, individuals with unstable angina can take an active role in managing their condition and reducing their risk of more severe cardiovascular events.

Sources

• Unstable Angina – American Heart Association
• Unstable Angina: Symptoms & Treatment
• Angina – NHS
• Angina – Symptoms and causes – Mayo Clinic