Cardiology Flashcards
Which coronary artery supplies the anterior septum and anterior left ventricular wall?
Left anterior descending
Which coronary artery supplies the marginal branches of the left atrium and ventricle?
Left circumflex artery
Which coronary artery supplies the right atrium and ventricle?
Right coronary artery
Which coronary artery supplies the the posterior septum and the posterior right ventricular wall?
Right posterior descending
Which coronary artery supplies the sinus and AV nodes?
Usually a branch of the right coronary artery but it can be the left too
How does atherosclerosis form?
- Initial endothelial dysfunction
- Fatty infiltration of the sub endothelial space by LDL particles
- Migration of monocytes from the blood, which differentiate into macrophages, and then take up LDLs to become foam cells
- Smooth muscle proliferates and forms a fibrous capsule around the fatty streak
- Narrowed lumen
What are the complications of atherosclerosis?
- Progressive stenosis causing angina
2. Thromboemboli causing MI
What are the symptoms of angina?
Central chest pain on exertion, which radiates to the jaw or arm.
Associated with SoB, sweating, nausea
What are the symptoms of unstable angina?
As angina, but symptoms occur at rest
How should CHD be investigated?
- Exercise tolerance test
- Metabolic perfusion scan
- Stress echo
- PET
- Echogardiogram (USS)
- Cardiac CT
- Angiography (used to determine management)
- Nuclear imaging
How should stable angina be managed medically?
Antiplatelets - 75mg aspirin daily
Beta-blockers - atenolol, bisoprolol
Nitrates - GTN spray PRN (can become tolerant)
Calcium channel blockers - nifedipine, viramipril
Lipid lowering - statins
ACE inhibitors - ramipril
How is a STEMI treated?
Morphine Oxygen Nitrates (GTN) Aspirin (give 1st - 300mg) Clopidogrel
If within 120 mins:
Fibrinolysis with alteplase
If within 12 hours:
PCI - stent can be inserted to stenosed areas, and a balloon used to inflate it. Heparin is given during the procedure. Aspirin and clopidogrel are given before and after
Anticoagulate - bivalirudin
What is the treatment for a patient who has angina which doesn’t respond to treatment, and is not suitable for angioplasty?
Coronary artery bypass graft - usually reserved for 3 vessels or more
Uses saphenous and mammary veins
What are the symptoms of a STEMI/NSTEMI?
Crushing chest pain, sense of impeding doom, cold and clammy, nauseous
What is the difference between STEMI AND NSTEMI?
STEMI - coronary artery completely occluded
NSTEMI - partially occluded
If a NSTEMi develops pointed T waves or Q waves what should you be worried about?
Progression to STEMI
What does unstable angina look like on an ECG?
ST depression (myocardial ischaemia)
How is a STEMI diagnosed?
ECG changes in 2 contiguous leads:
- 2mm ST elevation in chest leads
- 1mm ST elevation in limb leads
- new LBBB
What leads represent the left anterior descending artery?
V1-4 (chest)
What leads represent the right coronary artery (inferior)
II, III, aVF
What leads represent the left circumflex artery (lateral)
I, aVL, V5 V6
What can cause ST elevation?
LBBB, MI, pericarditis, coronary spasm
What can cause ST depression?
Digoxin, myocardial ischaemia, hypokalemia, hypothermia, stroke