Stable Angina Symptoms - 6S Mnemonic for Easy Diagnosis

By -VHTC

25 July

Stable angina is a classic symptom of coronary artery disease (CAD), often considered a warning sign of underlying myocardial ischemia. It is characterized by chest pain that occurs with physical exertion or emotional stress and is relieved by rest or medication. For clinicians, students, and patients alike, recognizing the hallmark features of stable angina is crucial for timely diagnosis and management.

To aid in recall and rapid recognition, the mnemonic “6S” offers an intuitive and comprehensive guide to understanding the clinical profile of stable angina.

What Is Stable Angina?

Stable angina pectoris refers to predictable chest pain that occurs when myocardial oxygen demand exceeds supply, usually during physical or emotional stress. It typically resolves with rest or the use of nitrates.

Unlike unstable angina or myocardial infarction, stable angina:

Does not occur at rest
Is not associated with acute plaque rupture
Is more predictable and manageable

Pathophysiology of Stable Angina

Stable angina results from myocardial ischemia, typically due to atherosclerotic narrowing of coronary arteries.

Mechanism:

Coronary artery lumen narrowed by atherosclerotic plaque
During stress or exertion, the oxygen demand of the heart increases
The compromised artery cannot supply sufficient oxygen
Anaerobic metabolism and lactic acid accumulation trigger chest pain

Reversibility: The ischemia in stable angina is transient and does not cause permanent myocardial damage, distinguishing it from infarction.

Stable Angina Symptoms - 6S Mnemonic for Easy Diagnosis

Mnemonic: “6S” of Stable Angina

This creative mnemonic captures the six most characteristic features of stable angina:

S – Sudden Onset
S – Substernal Pain
S – Spread to Arm
S – Squeezing in Nature
S – Short Duration
S – Sublingual GTN Relieves Pain

Let's unpack each "S" in detail:

1. Sudden Onset

Description:
The chest pain in stable angina begins suddenly, usually triggered by:

Physical exertion (walking, climbing stairs)
Emotional stress
Cold exposure
Heavy meals

Clue for Diagnosis:
The predictability of pain with specific triggers is a key feature distinguishing stable from unstable angina.

Why it matters:
Sudden onset with exertion signals ischemia — prompting the need for risk assessment and therapy initiation.

2. Substernal Pain

Location:
Pain is typically felt behind the sternum (breastbone), in the central chest.

Patient Description:

"Pressure," "tightness," "heaviness," or "burning" in the chest
May mistakenly be described as heartburn

Diagnostic Importance:
Substernal location is part of the typical angina triad along with exertional onset and relief with rest.

3. Spread to Arm

Radiation Pattern:
Pain often radiates to:

Left arm (most common)
Neck or jaw
Back
Occasionally the right arm or epigastrium

Clinical Insight:
Pain radiation reinforces the diagnosis and helps differentiate angina from non-cardiac causes like musculoskeletal chest pain.

4. Squeezing in Nature

Quality of Pain:
Patients often describe the discomfort as:

Squeezing
Pressing
Constricting
Like a “tight band” around the chest

Contrast with:

Sharp, stabbing, pleuritic pain — suggestive of pericarditis or pulmonary embolism
Positional pain — suggestive of musculoskeletal issues

5. Short in Duration

Time Frame:
Typically lasts for 2–10 minutes and resolves with rest or medication.

Not Characteristic Of:

Pain lasting >20 minutes → suspect unstable angina or myocardial infarction
Pain <1 minute → likely non-cardiac

Significance:
The short duration underscores that myocardial damage has not yet occurred — making this a window of opportunity for intervention.

6. Sublingual GTN ↓ Pain

GTN (Glyceryl Trinitrate):

A vasodilator that increases coronary blood flow and reduces preload
Commonly taken sublingually during anginal episodes

Response in Stable Angina:

Rapid relief of pain within 1–3 minutes is typical

Clinical Implication:

Positive response to GTN helps confirm angina diagnosis
Failure to respond may point to other pathologies or unstable angina

Summary Table: 6S Mnemonic for Stable Angina

S #	Feature	Explanation
1	Sudden Onset	Triggered by exertion, emotional stress
2	Substernal Location	Central chest pain, classic ischemic pattern
3	Spread to Arm	Radiates to left arm, neck, jaw
4	Squeezing in Nature	Tight, heavy, or pressure-like pain
5	Short in Duration	<10 minutes, resolves with rest
6	Sublingual GTN Relief	Rapid response confirms ischemic origin

Risk Factors for Stable Angina

Age >50 years
Hypertension
Diabetes Mellitus
Dyslipidemia
Smoking
Obesity
Family history of CAD
Sedentary lifestyle
Stress and poor diet

Investigations for Suspected Stable Angina

1. ECG (at rest):

May show normal results
Can show old ischemic changes: ST depression, T-wave inversion

2. Stress Test:

Treadmill test (TMT)
Stress echocardiography
Nuclear perfusion scanning

3. Echocardiogram:

Assess LV function and wall motion

4. Coronary Angiography:

Definitive for evaluating coronary artery stenosis

5. Blood Tests:

Troponin: Normal in stable angina
Lipid profile, HbA1c, renal function

Treatment of Stable Angina

1. Lifestyle Modification:

Smoking cessation
Regular exercise
Weight reduction
Heart-healthy diet (DASH/Mediterranean)
Stress management

2. Pharmacological Therapy:

Class	Drugs	Action
Nitrates	GTN, Isosorbide dinitrate	Vasodilation, ↓ preload, ↑ perfusion
Beta-blockers	Metoprolol, Atenolol	↓ HR and myocardial oxygen demand
Calcium channel blockers	Amlodipine, Diltiazem	Coronary vasodilation
Antiplatelet agents	Aspirin, Clopidogrel	Prevent thrombosis
Statins	Atorvastatin, Rosuvastatin	Lower LDL, stabilize plaque
ACE Inhibitors	Ramipril, Lisinopril	Cardio-protective in diabetics and hypertensives

3. Revascularization (for refractory symptoms):

Percutaneous Coronary Intervention (PCI): Angioplasty + stenting
Coronary Artery Bypass Grafting (CABG): For multi-vessel disease

Stable Angina vs. Unstable Angina

Feature	Stable Angina	Unstable Angina
Trigger	Exertion or stress	Occurs at rest or minimal exertion
Duration	<10 min	>20 min
Response to GTN	Good	Partial or no relief
ECG	Often normal	ST depression or T-wave inversion
Troponin	Negative	Negative
Urgency	Outpatient management	Medical emergency

Prognosis of Stable Angina

With proper medical management, lifestyle changes, and regular follow-up, stable angina has a good prognosis. However, lack of treatment may progress to unstable angina or myocardial infarction.

Red Flag Symptoms (Seek Emergency Care):

Chest pain at rest
Pain lasting >15 minutes
New or worsening angina
Syncope, palpitations, or breathlessness

Frequently Asked Questions (FAQs)

What is the “6S” mnemonic for stable angina?

The 6S mnemonic stands for: Sudden onset, Substernal, Spread to arm, Squeezing in nature, Short duration, and Sublingual GTN relief — capturing classic angina symptoms.

How do I know if my chest pain is angina?

If your chest pain starts with exertion, feels like pressure, radiates to the arm, and goes away with rest or nitrates — it’s likely angina. But always consult a doctor for ECG and evaluation.

Is stable angina reversible?

While the symptoms can be managed and the risk reduced, the underlying atherosclerosis is usually not reversible but can be slowed with lifestyle and medication.

Can women present differently?

Yes. Women may have more atypical symptoms such as fatigue, nausea, shortness of breath, or back pain instead of classic chest pain.

What is the first-line treatment for stable angina?

Lifestyle modification, nitrates for acute relief, beta-blockers for long-term symptom control, and aspirin/statins for cardiovascular protection.

Conclusion: Stability Begins with “6S”

Stable angina is a manageable yet serious cardiac condition that signals underlying coronary artery disease. Recognizing the “6S” — sudden onset, substernal location, spread to arm, squeezing quality, short duration, and sublingual relief — can lead to early diagnosis, better treatment, and improved outcomes.

Stable Angina Symptoms - 6S Mnemonic for Easy Diagnosis

What Is Stable Angina?