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
What is heart failure?
Cardiac output is inadequate for the body’s requirements
What causes heart failure?
Hypertension, IHD, valvular disease, arrhythmias, cardiomyopathies, thyroid defects, pregnancy, chronic disease
How should heart failure be diagnosed?
CLINICAL, Pro-BNP, Echo
What are the symptoms of heart failure?
NO CHEST PAIN, fatigue, dyspnoea (PND, orthopnoea), wheeze, cold peripheries, weight loss
How should HF be managed?
- Diuretics (loops relieve symptoms)
- ACE-i
- B-blockers (with caution)
- Spironolactone (K sparing diuretic)
- Digoxin (although normally used for AF)
- Vasodilators
How should decompensated heart failure be treated? (LMNOP)
Lasix (furosemide) Morphine Nitrates (GTN) Oxygen Position (not flat)
What devices can be used when medication isn’t working?
- Internal cardiac defibrillator
- Left ventricular assist device
If someone is prescribed ACEis, what measures should be taken?
RENOTOXIC - monitor UandE within 2 weeks of prescription and repeat every 3-6 months
What are the signs of decompensated heart failure?
Pink, frothy sputum Orthopnea Wheezing Anxiety Sweating
What does a non-pulsatile JVP mean?
Superior vena cava obstruction
What does the a wave represent in the JVP waveform?
Atrial contraction
absent in AF
What is a cannon a wave caused by?
Complete heart block, VT
What does the c wave represent in the JVP waveform?
Closure of tricuspid valve
not normally visible
What does the x wave represent in the JVP waveform?
Fall in atrial pressure during ventricular systole
What does the v wave represent in the JVP waveform?
Passive filling of blood into the atrium
What does the y descent represent in the JVP waveform?
Opening of tricuspid valve
What is pericarditis, and what causes it?
Inflammation of the pericardium due to:
- Viruses (EBV, coxsackie, HIV)
- Bacteria (TB)
- MI (dresslers syndrome)
- Autoimmune (rheumatoid, SLE)
What are the symptoms of pericarditis?
Sharp retrosternal pain, relieved by sitting forwards
Radiates to left arm
What is HCOM?
Autosomal dominant LV hypertrophy, usually of the septum.
What are the symptoms of HCOM?
Dyspnoea, angina, palpitations, syncope
Ejection systolic murmer at left sternal edge
What is rheumatic fever?
A multisystem immune disease following infection with group A strep
What are the features of rheumatic fever, according to the Jones criteria?
Polyarthritis Carditis Syndenhams chorea Erythema marginatum (painless rash) Subcutaneous nodules
What is cardiac tamponade, and what are the symptoms?
When fluid in the pericardium compresses the heart, causing:
- Dypsnoea
- Tachycardia
- Hypotension
- Muffled heart sounds
- Pulsus paradoxus
How does cardiac tamponade affect the JVP?
Raised JVP with an absent Y descent
What is pulses paradoxus?
An abnormally large decreases in systolic blood pressure during inspiration (>10mmhg)
What is the Vaughan-Williams classification?
A method of classifying antiarrhythmics, such as: 1a - quinidine 1b - lidocaine 1c - fleicanide (all block sodium channels)
2 - propanolol, atenolol (beta blocker)
3 - amiodarone (potassium channel blocker)
4 - verapamil (calcium channel blocker)
What is amiodarone?
A potassium channel blocker that is used in life-threatening arrhythmias such as VF and VT
What is torsade de pointes?
A form of VT with a constantly varying axis and long QT syndrome, associated with electrolyte deficiencies
What is broad complex tachycardia?
ECG rate >100bpm and QRS>120ms
What causes broad complex tachycardia?
Ventricular tachycardia (pulseless VT, torsade de points) SVT with aberrant conduction
How is broad complex tachycardia managed?
Mild - correct electrolyte problems
Severe - sedation, then shock, then amiodarone
What is a narrow complex tachycardia?
ECG rate >100bpm and QRS<120ms
What causes narrow complex tachycardia?
Sinus tachycardia Atrial tachyarryhthmias (AF, flutter) Junctional tachycardia (AVNR, AVR)
What is the significance of a P wave buried in the QRS complex or occurring after it?
Junctional narrow complex tachycardia:
- AVNR
- AVR (eg. WPW)
How is narrow complex tachycardia managed?
Mild (AF, flutter) - rate control (b-blocker)
Severe (SCT, junctional tachycardia) - adenosine, verapamil or b-blockers
