Cardiology Flashcards
(86 cards)
Atherosclerosis definition
Combination of fatty deposits in artery walls (atheromas) and hardening/ stiffening of vessel walls (sclerosis)
Consequences of atherosclerosis
- stiffening of artery walls -> extra resistance against blood flow -> high blood pressure -> inc strain on the heart
- stenosis -> reduced blood flow (eg angina)
- plaque rupture -> thrombus -> vessel blocked -> ACS
CVD non-modifiable risk factors
- Older age
- Family history
- Male
CVD modifiable risk factors
- Raised cholesterol
- Smoking
- Alcohol consumption
- Poor diet
- Lack of exercise
- Obesity
- Poor sleep
- Stress
End results of atherosclerosis
- Angina
- Myocardial infarction
- Transient ischaemic attacks
- Strokes
- Peripheral arterial disease
- Chronic mesenteric ischaemia
What does QRISK3 calculate
percentage risk that a patient will have a stroke or myocardial infarction in the next 10 years
QRISK3: what threshold for what intervention?
10% or above - should be offered statin
How soon should lipids be checked after starting a statin?
- check 3 months after starting
- increase dose to aim for a greater than 40% reduction in non-HDL cholesterol
When should LFT’s be checked after starting a statin
- check within 3 months of starting and again at 12 months
- Statins can cause a transient and mild rise in ALT and AST in the first few weeks of use - only need to be stopped if rise is <3 times the upper limit of normal
Statin side effects
- Myopathy (causing muscle weakness and pain)
- Rhabdomyolysis (muscle damage – check the creatine kinase in patients with muscle pain)
- Type 2 diabetes
- Haemorrhagic strokes (very rarely)
Statins should be stopped when taking which medication?
macrolide abx (clarithromycin/ erythromycin)
4 methods of secondary prevention of CVD
4 A’s (depends on condition):
* Antiplatelet medications (e.g., aspirin, clopidogrel and ticagrelor)
* Atorvastatin 80mg
* Atenolol (or an alternative beta blocker – commonly bisoprolol) titrated to the maximum tolerated dose
* ACE inhibitor (commonly ramipril) titrated to the maximum tolerated dose
Clinical diagnosis of familial hypercholesterolaemia
* Family history of premature cardiovascular disease (e.g., myocardial infarction under 60 in a first-degree relative)
* **Very high cholesterol **(e.g., above 7.5 mmol/L in an adult)
* **Tendon xanthomata **(hard nodules in the tendons containing cholesterol, often on the back of the hand and Achilles)
At what threshold of sclerosis do exertional symptoms show?
70-80% sclerosed
Cause of angina
- atherosclerosis of coronary arteries -> reduced blood flow to the heart
- high oxygen demand (eg exercise) -> insufficient blood supply -> chest pain
Stable vs unstable angina
- “stable” = symptoms only come on with exertion, always relieved by rest or GTN spray
- “unstable” = symptoms appear randomly at rest -> ACS, requires immediate management
Angina investigations
- Physical examination (e.g., heart sounds, signs of heart failure, blood pressure and BMI)
- ECG (a normal ECG does not exclude stable angina)
- FBC (anaemia)
- U&Es (required before starting an ACE inhibitor and other medications)
- LFTs (required before starting statins)
- Lipid profile
- Thyroid function tests (hypothyroidism or hyperthyroidism)
- HbA1C and fasting glucose (diabetes)
What does cardiac stress testing involve?
- assesses heart function during exertion
- stress the heart with exercise (eg treadmill) or medication (eg dobutamine)
- cardiac function assessed via ECG, echocardiogram, MRI or a myocardial perfusion scan (nuclear medicine scan)
2 types of coronary angiography
- CT coronary angiography - inject contrast and take CT images
- Invasive coronary angiography - insert catheter into radial/ femoral artery, direct through to coronary arteris, inject contrast and take X-ray images (gold standard)
Stable angina management
- R – Refer to cardiology
- A – Advise them about the diagnosis, management and when to call an ambulance
- M – Medical treatment
- P – Procedural or surgical interventions
- S – Secondary prevention
3 aims of medical management of stable angina
- Immediate symptomatic relief during episodes of angina - GTN spray
- Long-term symptomatic relief - beta blocker +/- CCB, specialist drugs (isosorbide mononitrate, Ivabradine, Nicorandil, Ranolazine)
- Secondary prevention of cardiovascular disease (4A’s)
How does GTN work
- GTN causes vasodilation by relaxing vascular smooth muscle
How to use GTN spray
- Take the GTN when the symptoms start
- Take a second dose after 5 minutes if the symptoms remain
- Take a third dose after a further 5 minutes if the symptoms remain
- Call an ambulance after a further 5 minutes if the symptoms remain
What does percutaneous coronary intervention involve?
- inserting catheter into radial/ femoral artery
- guided to coronary arteries -> contrast injected to identify areas of stenosis -> dilate balloon to widen the lumen (angioplasty) and insert stent to keep it open