Angina (Stable)

Question 1

What is angina?

Answer 1

Angina is pain (or constricting discomfort) in the chest, in the neck, shoulders, jaw, or arms caused by an insufficient blood supply to the myocardium.

Question 2

What is stable angina?

Answer 2

Usually occurs predictably with physical exertion or emotional stress, last for no more than 10 minutes (usually less) and is relieved within minutes of rest, as well as sublingual nitrates.

Question 3

Briefly describe the cause of angina

Answer 3

Angina is usually caused by coronary artery disease- atherosclerotic plaques in the coronary arteries cause progressive narrowing of the lumen, and symptoms occur when blood flow does not provide adequate amounts of oxygen to the myocardium at times when oxygen demand increases (such as during exercise).

Less commonly, angina is caused by valve disease (for example aortic stenosis), hypertrophic obstructive cardiomyopathy, or hypertensive heart disease.

Question 4

What risk factors are associated with stable angina?

Answer 4

• Smoking
• Hypertension
• Hyperlipidaemia
• Isolated low HDL cholesterol
• Diabetes
• Inactivity
• Obesity
• Family history of coronary heart disease
• Male sex
• Illicit drug use

Question 5

What are the signs of stable angina?

Answer 5

Physical examination is often normal or non-specific in patients with stable angina but may reveal signs of associated conditions such as heart failure, valvular disease, or hypertrophic cardiomyopathy

Question 6

What are the symptoms of stable angina?

Answer 6

• Typical angina presents with all three of the following features:
  
  • Precipitated by physical exertion.
  • Constricting discomfort in the front of the chest, in the neck, shoulders, jaw, or arms.
  • Relieved by rest or glyceryl trinitrate (GTN) within about 5 minutes.
• Atypical angina presents with two of the above features.
  
  • In addition, atypical symptoms include gastrointestinal discomfort, and/or breathlessness and/or nausea.

Question 7

What investigations should be ordered for stable angina?

Answer 7

• CT Coronary Angiography (Gold Standard diagnostic investigation)
• ECG
• FBC (including haemoglobin)
• LFT
• U&E
• Lipid profile
• Fasting blood glucose or HbA₁c
• Thyroid function tests

Question 8

Briefly describe the use of CT Coronary Angiography

Answer 8

The Gold Standard diagnostic investigation. This involves injecting contrast and taking CT images timed with the heart beat to give a detailed view of the coronary arteries, highlighting any narrowing.

Question 9

Why investigate using ECG?

Answer 9

Resting ECG is appropriate for initial evaluation of all patients with known or suspected ischaemic heart disease. In addition to providing diagnostic and prognostic information, the presence of baseline ECG abnormalities may also guide use of further testing such as echocardiography and stress testing.

Often normal, but may reveal ST-T changes suggestive of ischaemia or Q waves indicative of prior infarction.

Question 10

Why investigate FBC (including haemoglobin)?

Answer 10

Anaemia results in additional cardiac workload and reduced oxygen delivery to the heart, which can exacerbate angina. Severe anaemia may cause angina without obstructive coronary lesions.

Question 11

Why investigate LFT?

Answer 11

Prior to starting statins.

Question 12

Why investigate U&E?

Answer 12

Prior to starting ACEi and other meds.

Question 13

Why investigate lipid profile?

Answer 13

Dyslipidaemia is an important risk factor for ischaemic heart disease.

Elevated LDL cholesterol is associated with increased risk; elevated HDL is protective.

Question 14

Why investigate fasting blood glucose or HbA₁c?

Answer 14

Diabetes is an important risk factor for ischaemic heart disease.

Elevated in diabetes.

Question 15

Why investigate thyroid function?

Answer 15

Rule out hyper- or hypo- thyroidism.

Question 16

What is the management of stable angina?

Answer 16

R- Refer to cardiology (urgently if unstable)

A- Advise them about the diagnosis, management and when to call an ambulance

M- Medical treatment

P- Procedural or surgical interventions

Question 17

Briefly descirbe lifestyle education in treating stable angina

Answer 17

All patients should be provided with individualised patient education and guideline-directed medical therapy with the goals of reducing the risk of future cardiovascular events and reducing anginal symptoms.

Patient education includes ongoing assessments and recommendations to help patients achieve weight management, increased physical activity, dietary modifications, lipid goals, and smoking cessation.

Question 18

Briefly describe the pharmacological treatment options in stable angina

Answer 18

• Antiplatelet therapy
• Beta-blockers
• Renin-angiotensin-aldosterone antagonists
• Lipid management
• Blood pressure control
• Diabetes management
• Anti-anginal pharmacotherapy

Question 19

What treatment is used for immediate symptomatic relief?

Answer 19

Their GTN spray is used required. It causes vasodilation and helps relieves the symptoms.

Take GTN, then repeat after 5 minutes. If there is still pain 5 minutes after the repeat dose – call an ambulance.

Question 20

What treatment is used for long term symptomatic relief?

Answer 20

Either (or used in combination if symptoms are not controlled on one):

• Beta blocker (e.g. bisoprolol 5mg once daily)
• Calcium channel blocker (e.g. amlodipine 5mg once daily)

Question 21

What treatment is used for secondary prevention?

Answer 21

• Aspirin (i.e. 75mg once daily)
• Atorvastatin 80mg once daily
• ACE inhibitor
• Already on a beta-blocker for symptomatic relief

Question 22

Briefly describe the antiplatelet therapy in stable angina

Answer 22

All patients should be started on aspirin and this should be continued indefinitely. For patients with a contraindication to aspirin therapy, it is reasonable to use clopidogrel.

Question 23

Briefly describe the lipid-lowering therapy in stable angina

Answer 23

High-intensity statin therapy is indicated for most patients with stable angina and is the mainstay of lipid pharmacotherapy.

Statins include atorvastatin, rosuvastatin and simvastatin.

Question 24

Briefly describe blood pressure control in stable angina

Answer 24

There is consensus that antihypertensive medications are warranted for patients with stable angina whose blood pressure is >140/90 mmHg.

Beta-blockers and ACE inhibitors or angiotensin-II receptor antagonists are indicated regardless of blood pressure for some patients (i.e., those with left ventricular dysfunction, myocardial infarction in the past 3 years, or stable angina).

Question 25

Briefly describe the use of beta blockers in stable angina

Answer 25

Beta-blockers decrease heart rate and myocardial contractility and, in turn, **reduce myocardial oxygen demand and anginal symptoms.** These agents have been shown to **significantly improve mortality rates** among patients with prior MI and, in combination with ACE inhibitors, among those with reduced left ventricular (LV) function.

Question 26

Briefly describe blood sugar control in stable angina

Answer 26

Patients with ischaemic heart disease and diabetes mellitus are at high risk of morbidity and mortality from cardiovascular events. In type 1 diabetes, glycaemic control **reduces the risk of macrovascular complications** including angina, MI, and need for revascularisation.

Question 27

What are the surgical interventions in stable angina?

Answer 27

Revascularisation, either by **coronary artery bypass graft (CABG) surgery** or by **percutaneous coronary intervention (PCI)**, may be indicated to improve either the quality or quantity of life.

Question 28

What is percutaenous coronary intervention (PCI)? And when is it used?

Answer 28

Percutaneous Coronary Intervention (PCI) with coronary angioplasty (dilating the blood vessel with a balloon and/or inserting a stent) is offered to patients with **“proximal or extensive disease”** on CT coronary angiography. This involves putting a catheter into the patient’s **brachial or femoral artery**, feeding that up to the coronary arteries under **xray** guidance and injecting contrast so that the coronary arteries and any areas of stenosis are highlighted on the xray images. This can then be treated with **balloon dilatation followed by insertion of a stent.**

Question 29

What is coronary artery bypass graft (CABG)? And when should it be used?

Answer 29

Coronary Artery Bypass Graft (CABG) surgery may be offered to patients with **severe stenosis**. This involves **opening the chest along the sternum** (causing a midline sternotomy scar), taking a graft vein from the patient’s leg (usually the great saphenous vein) and **sewing it on to the affected coronary artery to bypass the stenosis**. The recovery is slower and the complication rate is higher than PCI.

Question 30

Briefly describe the use of sublingual glyceryl trinitrate in stable angina

Answer 30

**Sublingual glyceryl trinitrate** is the preferred therapy to terminate acute episodes of angina or for prophylaxis before activities known to induce anginal symptoms. The mechanism of action is to **reduce left ventricular wall stress** and associated myocardial oxygen demand through **systemic vasodilation**. Coronary blood flow is also increased by coronary vasodilation. Onset of action is within minutes. Failure to resolve anginal symptoms with a reduction in physical activity and a trial of sublingual glyceryl trinitrate should prompt emergency evaluation for an acute coronary syndrome (unstable angina or myocardial infarction).

Question 31

What complictions are associated with stable angina?

Answer 31

* Myocardial infarction * Ischemic cardiomyopathy/ heart failure * Sudden cardiac death

Question 32

What differentials should be considered for stable angina?

Answer 32

1. Aortic dissection 2. Pericarditis 3. Pulmonary embolism

Question 33

How does stable angina and aortic dissection differ?

Answer 33

Differentiating signs and symptoms: t * The pain of aortic dissection is typically severe, sudden in onset, and often described as tearing, sharp, or stabbing * The pain may be retrosternal, interscapular, abdominal, or in the neck, lower back, or lower extremities * Hypertension is common with distal aortic dissections * Pulse deficits are common, particularly in proximal dissections Differentiating investigations: * Chest radiograph may show a widened mediastinum, leading to initial suspicion * Contrast-enhanced CT or transoesophageal echocardiogram will demonstrate the presence of a true and false lumen with dissection flap

Question 34

How does stable angina and pericarditis differ?

Answer 34

Differentiating signs and symptoms: * The pain of acute pericarditis is typically severe, sudden in onset, and retrosternal or left precordial in location * The chest pain is often pleuritic, aggravated by supine positioning and relieved by sitting upright * A pericardial friction rub may be appreciated on examination Differentiating investigations: * ECG will show diffuse ST-segment elevation and PR-segment depression

Question 35

How does stable angina and pulmonary embolism differ?

Answer 35

Differentiating signs and symptoms: * Dyspnoea is the most common symptom of acute pulmonary embolus * History may reveal symptoms of lower extremity venous thrombosis (erythema, warmth, pain, or swelling) * Tachypnoea and tachycardia are the most common signs Differentiating investigations: * D-dimer: normal value is useful to rule out pulmonary embolism in patients with low clinical probability of pulmonary embolism. * An ECG is useful to exclude alternate diagnosis. * Non-specific findings seen with pulmonary embolism include ST abnormalities, T-wave changes and right or left axis deviation