Introduction

Acute Coronary Syndrome (ACS) is a critical subtopic in Cardiology that every clinical pharmacist should understand. ACS refers to a spectrum of conditions characterized by decreased blood flow in the coronary arteries, such as unstable angina and myocardial infarction. It is a medical emergency, and early recognition and management can significantly improve patient outcomes. As pharmacists play a vital role in the multidisciplinary team managing these conditions, an in-depth understanding of ACS is essential.

Clinical Presentation

Acute Coronary Syndrome (ACS) typically presents with chest pain, often described as a crushing, burning, or pressure-like sensation, which may radiate to the jaw, neck, arms, or back. Other symptoms include shortness of breath, nausea, vomiting, diaphoresis, and light-headedness. It’s worth noting that some patients, particularly women, the elderly, and those with diabetes, may present with atypical symptoms or be asymptomatic.

Risk Factors for ACS

Modifiable Risk Factors:

• Hypertension
• Hyperlipidemia
• Diabetes Mellitus
• Smoking
• Obesity
• Sedentary lifestyle
• Unhealthy diet

Non-modifiable Risk Factors:

• Age (men >45 years, women >55 years)
• Family history of premature coronary artery disease
• Gender (male)
• Ethnicity

The disease state is more common in older adults, with the incidence and prevalence increasing significantly with age. It also tends to affect more men than women, although post-menopausal women are at a similar risk as men.

Risk Stratification Tools

TIMI Score (Thrombolysis in Myocardial Infarction)

Purpose: Evaluates the risk of death, new or recurrent myocardial infarction (MI), and the need for urgent revascularization within 14 days in patients with unstable angina and NSTEMI.

• Age ≥ 65 years
• At least three risk factors for coronary artery disease (CAD)
• Prior coronary artery stenosis ≥ 50%
• Use of aspirin in the last 7 days
• At least two episodes of angina in the last 24 hours
• Elevated cardiac biomarkers
• ST-segment deviation ≥ 0.5 mm on admission ECG

Scoring: Each factor scores 1 point. A higher score correlates with a higher risk of adverse cardiac events.

Reference: Antman EM, Cohen M, Bernink PJ, et al. The TIMI risk score for unstable angina/non–ST elevation MI: A method for prognostication and therapeutic decision making. JAMA. 2000;284(7):835-842. doi:10.1001/jama.284.7.835

GRACE Score (Global Registry of Acute Coronary Events)

Purpose: Assesses the risk of in-hospital and 6-month mortality in patients with ACS, applicable to both STEMI and NSTEMI.

• Age
• Heart rate
• Systolic blood pressure
• Serum creatinine level
• Cardiac arrest at admission
• ST-segment deviation on admission ECG
• Elevated cardiac biomarkers (troponin or CK-MB)
• Killip class (a classification of heart failure severity)

Scoring: Each factor is assigned a specific number of points, and the total score corresponds to a percentage risk of mortality.

Reference: Granger CB, Goldberg RJ, Dabbous O, et al. Predictors of hospital mortality in the global registry of acute coronary events. Arch Intern Med. 2003;163(19):2345-2353. doi:10.1001/archinte.163.19.2345

Pathophysiology

Acute Coronary Syndrome (ACS) is primarily caused by an imbalance between myocardial oxygen supply and demand, leading to ischemia. This imbalance can occur due to various reasons, with the most common being the rupture of an atherosclerotic plaque in the coronary arteries.

Key Mechanisms

Pharmacists should understand that the key goal in ACS management is to restore the balance between myocardial oxygen supply and demand, reduce the extent of myocardial damage, and prevent complications.