Coronary Artery Disease: Symptoms, Treatment, and Complication Prevention

What is Coronary Artery Disease (CAD)?

Coronary artery disease (CAD) is a chronic condition in which the heart muscle (myocardium) does not receive a sufficient amount of oxygen and nutrients due to narrowing or blockage of the coronary arteries. Most often, the cause of such narrowing is atherosclerosis—the formation of cholesterol plaques on the walls of blood vessels.

CAD represents a wide spectrum of conditions, ranging from asymptomatic myocardial ischemia and stable angina to acute myocardial infarction and sudden cardiac death [3]. Manifestations of CAD also include unstable angina and coronary artery spasm, which can lead to serious complications, including syncope (fainting), heart failure, arrhythmias, and even sudden death [3].

Symptoms and Manifestations of CAD

Symptoms of coronary artery disease can vary significantly:

• Angina pectoris: this is the most common symptom. It manifests as a pressing, squeezing, or burning pain behind the sternum, which can radiate to the left arm, neck, lower jaw, back, or epigastric region. The pain usually occurs during physical exertion, stress, or exposure to cold and subsides at rest or after taking nitroglycerin [3].
• Asymptomatic myocardial ischemia: in some patients, ischemia can occur without any pain sensations, but characteristic changes are registered on the electrocardiogram (ECG) [3].
• Acute myocardial infarction (AMI): this is an emergency condition characterized by more intense and prolonged chest pain that is not relieved by nitroglycerin. The pain during a heart attack is often accompanied by shortness of breath, weakness, cold sweat, nausea, and a sense of fear [1, 3].
• Heart failure: can develop as a complication of CAD, especially after a myocardial infarction. Its symptoms include shortness of breath upon exertion or at rest, leg swelling, rapid fatigue, and decreased exercise tolerance [2, 6].
• Arrhythmias: heart rhythm disturbances, such as tachycardia or bradycardia, can also be a manifestation of CAD [3].

Diagnostics of CAD and Its Complications

Timely and accurate diagnosis of CAD and its complications is crucial for effective treatment. The diagnostic process includes:

• Anamnesis collection and physical examination: the physician evaluates the patient's complaints, risk factors, and medical history [1].
• Electrocardiography (ECG): allows for the detection of signs of ischemia, infarction, or arrhythmias [3].
• Blood tests: determination of cardiac enzyme levels (e.g., troponins) when myocardial infarction is suspected.
• Echocardiography (heart ultrasound): evaluates myocardial contractile function, identifies areas of impaired blood supply and the degree of heart failure.
• Stress tests: bicycle ergometry or treadmill test helps identify ischemia that manifests only during physical exertion.
• Coronary angiography: is the "gold standard" for assessing the state of the coronary arteries. This invasive procedure allows for the precise determination of the localization and degree of vascular narrowing, as well as the detection of coronary artery spasm using provocative tests [3].

In acute myocardial infarction or acute heart failure, rapid diagnosis and immediate initiation of treatment are extremely important [1].

Modern Approaches to CAD Treatment

Treatment of CAD aims to improve myocardial blood supply, reduce symptoms, prevent complications, and improve quality of life. It includes drug therapy, interventional methods, and lifestyle modifications.

Drug Therapy

• Antiplatelet agents: such as aspirin and clopidogrel, prevent blood clots from forming in the coronary arteries [5].
• Beta-blockers: reduce heart rate and blood pressure, decreasing the myocardium's oxygen demand. They improve prognosis in patients after myocardial infarction, especially in the presence of heart failure [4, 5, 8].
• ACE inhibitors and angiotensin II receptor blockers (ARBs): improve heart function and prognosis, especially in patients with heart failure and left ventricular dysfunction [4, 5, 8].
• Statins: lower blood cholesterol levels, stabilize atherosclerotic plaques, and reduce the risk of cardiovascular events [5].
• Nitrates: used to relieve angina attacks by dilating the coronary arteries [8].
• Diuretics: used in heart failure to reduce edema and shortness of breath [8].
• Aldosterone antagonists (e.g., eplerenone): indicated for patients with left ventricular dysfunction and heart failure or diabetes mellitus after myocardial infarction [4, 5].
• New medications: for example, levosimendan has shown safety and efficacy in improving symptoms and survival in patients with post-infarction heart failure [7].

Revascularization

In cases of significant narrowing of the coronary arteries, the following may be applied:

• Percutaneous coronary intervention (PCI): includes balloon angioplasty and stenting, restoring artery patency.
• Coronary artery bypass grafting (CABG): a surgical operation to create bypass routes for blood flow around blocked arteries.

Early revascularization is the only method proven to improve survival in patients with cardiogenic shock [2].

CAD Complications: Heart Failure and Myocardial Infarction

CAD can lead to serious, life-threatening complications.

Myocardial Infarction

Acute myocardial infarction is an emergency condition requiring immediate medical intervention [1]. It occurs when blood flow to a part of the heart muscle is completely blocked, leading to the death of myocardial cells. This damage can cause the development of heart failure.

Heart Failure (HF)

Heart failure is a leading cause of mortality in patients who have suffered an acute myocardial infarction (AMI) [2]. According to studies, HF develops in 14% to 36% of patients hospitalized with AMI [2]. The development of HF after a heart attack is due to a complex interaction of factors, such as large vessel obstruction, microvascular dysfunction, myocardial remodeling, inflammation, and neurohormonal activation [2, 6].

Cardiogenic shock is an extreme degree of heart failure after a myocardial infarction, characterized by very high mortality [2]. The presence of heart failure after a myocardial infarction increases the risk of death by 3–4 times [6]. Therefore, timely recognition and immediate initiation of HF treatment after AMI are critical for improving prognosis and reducing mortality [2].

Treatment of HF after a heart attack includes the use of beta-blockers, ACE inhibitors, angiotensin receptor blockers, aldosterone antagonists, diuretics, and, if necessary, implantable cardioverter-defibrillator (ICD) implantation or cardiac resynchronization therapy (CRT) [4, 5, 8]. Special attention is paid to elderly patients and women, in whom heart failure after myocardial infarction develops more frequently [8].

Prevention and Living with CAD

To prevent the development and progression of CAD, as well as to improve the prognosis in already diagnosed patients, the following are extremely important:

• Lifestyle modification: balanced nutrition, regular physical activity, quitting smoking, and moderate alcohol consumption.
• Risk factor control: maintaining normal blood pressure, cholesterol, and blood sugar levels.
• Regular medical supervision: continuous interaction with a cardiologist and compliance with all their recommendations.
• Adherence to the medication regimen: strict fulfillment of the doctor's prescriptions for drug therapy.

Sources

1. Acute myocardial infarction and congestive heart failure. (Emergency medicine clinics of North America, 1996)
2. The spectrum of post-myocardial infarction care: from acute ischemia to heart failure. (Progress in cardiovascular diseases, 2024)
3. Myocardial ischemia syndromes, heart failure syndromes, electrocardiographic abnormalities, arrhythmic syndromes, and angiographic diagnosis of coronary artery spasm: a literature review. (International journal of medical sciences, 2020)
4. Heart failure and non-ST-elevation myocardial infarction: a review of a common situation. (European journal of internal medicine, 2011)
5. Established and novel pharmacological treatments for post-myocardial infarction patients with heart failure: an evidence-based review. (Cardiovascular drugs and therapy, 2020)
6. Heart failure after myocardial infarction: clinical relevance and treatment. (Clinical cardiology, 2011)
7. Heart failure update. (European journal of heart failure, 1999)
8. Heart failure complicating acute myocardial infarction. (Clinics in geriatric medicine, 2007)

The information presented in this article is for reference purposes only and cannot replace an in-person consultation with a qualified medical specialist. Always consult a physician for the diagnosis and treatment of diseases.