17.3: Coronary Artery Disease III: Clinical Manifestations

Coronary Artery Disease (CAD) is a primary health risk worldwide, leading to significant morbidity and mortality. The condition arises from the buildup of atherosclerotic plaques within the coronary arteries, resulting in diminished blood supply to the heart muscle.

The clinical manifestations of CAD vary widely, from asymptomatic stages to severe, life-threatening conditions. Understanding these manifestations is crucial for early diagnosis and effective management.

Angina Pectoris: The Warning Chest Pain

Angina pectoris, commonly known as angina, is one of the primary manifestations of CAD. It includes chest pain that feels like pressure, squeezing, tightness, or burning. The pain or discomfort may spread to the shoulders, arms, neck, jaw, or back.

Additional symptoms include cold sweats, dizziness, lightheadedness, nausea, indigestion, neck pain, dyspnea, and weakness.

For women, symptoms often include pain in the middle of the back, unexplained shortness of breath, jaw discomfort, pressure, tightness, or burning in the chest, and stomach pain.

Myocardial Infarction (Heart Attack): A Critical Event

Myocardial infarction (MI) is a critical and often life-threatening manifestation of CAD. When a coronary artery becomes entirely obstructed, it results in the necrosis of the heart muscle. The clinical presentation of MI includes:

• Chest Pain: Intense, persistent pain or pressure radiating to the left arm, neck, jaw, or back. Unlike angina, MI pain is not relieved by rest or nitroglycerin.
• Dyspnea: Shortness of breath due to left ventricular dysfunction or pulmonary congestion.
• Diaphoresis: Excessive sweating, often accompanying severe pain.
• Nausea and Vomiting: Resulting from vagal stimulation or severe pain.
• Fatigue and Weakness: Common, especially in elderly patients.
• Other Symptoms: Dizziness, lightheadedness, and palpitations.

Heart Failure: Compromised Heart Function

Chronic coronary artery disease (CAD) can result in heart failure, which is characterized by the heart's reduced ability to pump blood effectively. Symptoms of heart failure include:

• Dyspnea: Shortness of breath, especially during exertion or when lying down.
• Edema: Swelling of the legs, ankles, and feet due to fluid retention.
• Fatigue: Persistent tiredness and reduced exercise tolerance.
• Cough: Often, a nocturnal cough is due to pulmonary congestion.
• Weight Gain: Rapid and unexplained weight gain due to fluid accumulation.

Arrhythmias: Disruptions in Heart Rhythm

CAD can predispose individuals to various arrhythmias due to ischemic damage to the heart's electrical conduction system. These can range from benign to potentially fatal and include:

• Atrial Fibrillation: Irregular, rapid heartbeat may result in stroke or heart failure.
• Ventricular Tachycardia: Rapid heart rate originating from the ventricles can deteriorate into ventricular fibrillation.
• Ventricular Fibrillation: Chaotic electrical activity in the ventricles, leading to cardiac arrest if not treated immediately.

Silent Ischemia: The Hidden Threat

Some individuals with CAD experience silent ischemia, where there is objective evidence of ischemia without the typical chest pain. This condition is more common in diabetics and can be detected through electrocardiograms or stress tests.

Sudden Cardiac Death: An Immediate Emergency

Sudden cardiac death is a catastrophic manifestation of CAD, often resulting from acute myocardial infarction or severe arrhythmia. It is comprised of a sudden loss of consciousness and requires immediate resuscitation efforts.