Stable Angina Flashcards
When severe, what might angina-like chest pain be accompanied with?
- Autonomic features e.g. sweating, nausea
What is angina?
Symptoms (such as chest pain/discomort/tightness, SOB etc…) due to blood - and hence oxygen- supply to heart muscle being reduced.
In other words “symptomatic reversible myocardial ischaemia”
NO INFARCTION OCCURS
Discuss the pathophysiology of angina (be specific about difference between stable & unstable angina)
- Stable angina: build up of atherosclerotic plaques in coronary arteries. Plaques are stable
- Unstable angina: build up of atherosclerotic plaques in coronary arteries which are unstable and have eroded/ruptured forming a thrombus which partially occludes the coronary artery
- *NOTE: NSTEMI and unstable angina have same pathophysiology- only difference is whether it causes infarction*
State and describe the four most common types of angina
- Stable angina: induced by effort, relieved by rest
- Unstable angina (cresendo angina): angina that occurs on minimal exertion or at rest. We also classify angina that is increasing in frequency and severity unstable angina
- Variant (Prinzmetal) angina: caused by coronary artery spasm
- Also have:*
- ** Cardiac syndrome X= symptoms of angina & positive exercise test yet normal coronary arteries on angiogram*
- Decubitus angina: precipitated by lying flat
The most common cause of stable angina is atheroma; state a few other possible rarer causes
- Anaemia
- Coronary artery spasm
- Aortic stenosis
- Tachyarrhythmias
- Hypertrophic cardiomyopathy
- Arteritis/small vessel disease
State some risk factors for developing stable angina
*NOTE: risk factors for stable angina are same as those for ACS
- Hypertension
- Diabetes
- Smoking
- Hypercholesterolaemia
- Family history
- Other vascular disease
- Age
- Male
- Obesity
- Low physical activity
State whether angina is likely or unlikely if pt says pain is:
- Continuous/prolonged
- Related to activity
- Brought on by breathing
- Other symptoms such as dizziness & dysphagia
- Continuous/prolonged= unlikely
- Related to activity= likely
- Brought on by breathing= unlikely
- Other symptoms such as dizziness & dysphagia= unlikely
State some symptoms of stable angina
- Chest pain/discomfort/constriction which may radiate to jaw, neck, shoulders or arms
- Pain brought on by exertion or other triggers e.g. emotion, cold, heavy meals
- Symptoms relieved within 5 minutes by rest and/or relieved by GTN
- Associated nausea, sweatiness, faintness
- Dyspnoea
We often talk about angina being typical, atypical or non-anginal; discuss what criteria we use to classify angina into these categories
We look at how many of the following features a pt has:
- Constricting/heavy discomfort to chest, jaw, neck, shoulders or arms
- Symptoms brought on by exertion
- Symptoms relieved within 5 mins or by GTN
All three= typical angina
Two features= atypical angina
No or one feature= non-anginal chest pain
Discuss what you might find on clinical examination of a pt with stableangina
- Tachycardia
- Tachypnoea
- Autonomic features: cold, sweaty, pale
- Signs of hypercholesteroleamia: premature corneal arcus, xanthelamsa, xanthoma
- Signs of smoking: odour, nicotine staining
- Other evidence of vascular disease: carotid bruits
- Signs of conditions which can cause decompensation of angina: anaemia, thyrotoxicosis
- Heart failure signs: raised JVP, peripheral oedema, bibasal creps
- Other causes of angina: arrhythmias, aortic stenosis, hypertrophic cardiomyopathy
State some alternative differentials for stable angina chest pain
Most Common
- MSK e.g. costochondritis, intercostal muscle spasm
- GORD
- Oesophageal spasm
- Psychogenic- anxiety & depression
Less common BUT IMPORTANT NOT TO MISS
- PE
- Aortic dissection
- ACS
- Pneumothorax
- Pericarditis
- Shingles
Why would you want a pts weight & height if you are suspecting any cardiovascular pathology?
Allow you to calculate BMI (obesity is risk factor for CVD)
What investigations would you want for someone presenting with what sounds like stable angina, include:
- Bedside
- Bloods
- Imaging
*Where possible, include the reason why you do each test
Bedside
- ECG
- Normal observations
- Weight & height
Bloods
- FBC (anaemia)
- U&Es
- TFTs (hyperthyroidism can cause myocardial ischaemia)
- Lipids (risk factor)
- HbA1c (diabetes as risk factor)
- Glucose (diabetes as risk factor)
Imaging
- CT coronary angiography (GOLD STANDARD)
State the 4 principles of management of stable angina (RAMP)
- R – Refer to cardiology (urgently if unstable)
- A – Advise them about the diagnosis, lifestyle modifications and when to call an ambulance
- M – Medical treatment
- P – Procedural or surgical interventions
Describe some lifestyle modifications you would advise for someone with stable angina
- Smoking cessation
- Improve diet:
- Lower salt
- Lower fat
- Increase fruit & veg
- Exercise
Discuss the pharmacological treatment of stable angina
*NOTE: to help, think about the two categories of drugs you need to prescribe: anti-anginal meds & CVD preventation meds
Anti-Anginal Medication
All patients should be started on:
- Sublingual GTN
- Beta blocker (or non-dihyrdopyridine CCB if BB contraindicated e.g. verapamil, ditliazem etc…)
If the above fails to control angina symptoms, consider:
- Switching to CCB if BB (and vice versa)
- Both beta blocker & CCB (if using both then should use a long acting dihydropyridine CCB e.g. modified release nifedipine, amlodipine)
- If on monotherapy and can’t tolerate addition of CCB or BB OR they are on dual therapy and awaiting assessment for PCI or CABG add one of:
- Isosorbide mononitrate (long acting nitrate)
- Ivabradine (5-7.5mg BD)
- Nicorandil
- Ranolazine
CVD Prevention
All patients should be started on:
- Asprin (75mg OD)
- Statin (atorvastatin 80mg OD)
Consider:
- ACE inhibitor (e.g. if coexisting HTN, heart failure, CKD, diabetes)
- **REMEMBER: if on CCB monotherapy it is non-dihydropyridine/rate-limiting CCB and if in combination with BB it is dihydropyridine e.g. amlodipine*
What should you advise a person regarding use of their GTN spray if it fails to relieve symptoms?
- Repeat GTN after 5 mins if first one didn’t have any effect
- If there is still pain after the repeat dose call ambulance
What are the main goals of treatment for stable angina?
- Reduce & manage symptoms to improve quality of life
- Reduce complications such as MI, death
Why do you want to slow heart rate in angina?
- Decrease HR, increase diastole, coronary arterys fill in diastole
- Decrease HR, decrease demand of heart
Giving beta blockers to angina pts nt only prevents angina symptoms but also reduces CVS mortality and morbidity; true or false?
True
Describe the mechanism of action of nicorandil
Has actions of both a nitrate and KATP channel acvitor. By binding to KATP channels it activates them and increase K+ efflux; this results in hyperpolarisation of cell (cell becomes more negative inside relative to outside) and thus prevents normal membrane depolarisation and consequent calcium influx. This leads to vasodilation. Works in angina by dilating coronary arteries.
There is value in adding a long acting nitrate to a patient on established on nicorandil and vice versa; true or false?
FALSE- there is no value in doing this; because they both do the same thing
A pt with angina can only be prescribed ivabradine if they fit what two criteria?
- Sinus rhythm
- HR is >70bpm
Should ivabradine be prescribed with diltiazem or verapamil?
Latest guidance is NO!
Describe the mechanism of action of ranolazine
New anti-anginal drug; below mechanism is proposed mechanism but yet to be fully understood.
- Blocks late inward Na+ channels in myocardium
- Decreases rise in Na+
- Rise in Na+ causes rise in Ca2+
- Therefore decrease in rise in Na+, decreases rise in Ca2+
- Relaxation
*NOTE: ranolazine shouldn’t be used if GFR <30 and should only be initiated by consulatants in chronic stable angina.
Discuss the potential complications of stable angina
- Progression to ACS (which can then has whole host of complications e.g. heart failure, arrhythmia_
- Stroke
- Death
If lifestyle modification & pharmacological intervention doesn’t work in the treatment of stable angina what could you do next?
- PCI
- CABG
For Prinzmetal angina, describe:
- What it is
- ECG changes
- Risk factors
- Triggers
- Spasm of coronary arteries leading to angina (usually at rest) in normal, non-stenosed arteries
- ST elevation (during pain)
- Smoking increases risk (hypertension & hypercholesterolaemia do not)
- Triggers:
- Cocaine
- Marijuana
- Low magnesium
- Amphetamine
What should you advise a person regarding use of their GTN spray if it fails to relieve symptoms?
Repeat GTN after 5 mins if first one didn’t have any effect
If there is still pain after the repeat dose call ambulance
What do NICE advise patients should do when taking standard release isosorbide mononitrate?
- many patients who take nitrates develop tolerance and experience reduced efficacy
- NICE advises that patients who take standard-release isosorbide mononitrate should use an asymmetric dosing interval to maintain a daily nitrate-free time of 10-14 hours to minimise the development of nitrate tolerance
- this effect is not seen in patients who take once-daily modified-release isosorbide mononitrate
