Cardio Flashcards
What happens in atherogenesis?
Damage to endothelial cells → endothelium secretes chemoattractants → leukocytes migrate and accumulate in intima → foam cells/macrophages/T-lymphocytes form fatty streaks → foam cells rupture, releasing lipids + SMC migrate from media to intima → dense, fibrous cap w necrotic core formed
This plaque can partially occlude the lumen → blood flood is restricted → ischemia
Plaque can rupture → thrombus formed →lumen is fully occluded → infarction
Which arteries does atherogenesis affect most commonly?
LAD, circumflex, RCA
What are the risk factors for IHD?
age
smoking
obesity, high serum cholesterol
diabetes
hypertension
family history
M>F
What is IHD?
cardiac myocyte damage (and eventual death) due to insufficient oxygen-rich blood
in ascending order of severity: stable angina> unstable angina > NSTEMI > STEMI
can be due to increased myocardial workload + coronary artery occlusion OR due to insufficient oxygen-rich blood supply
main causes: atheroma, valvular disease (aortic stenosis), anaemia (demand & supply)
What is angina?
Angina is the result of myocardial ischaemia, where blood supply < metabolic demand
What is stable angina?
chest pain precipitated by exposure to cold/exercise
lasts 1-5 minutes
relieved by rest/GTN spray
radiation of pain
induced by exertion
relieved by rest/GTN spray
What is unstable angina/stemi/nstemi?
chest pain at rest
prolonged, >20 minutes
no relief by rest/GTN spray
NSTEMI, STEMI: increase in troponin, myoglobin, CK levels
STEMI: ST-elevations on ECG
What is prinzmetal’s angina?
caused by coronary artery spasms; occur at rest/night
What are the symptoms of IHD?
chest pain: discomfort, heaviness, squeezing, burning
radiation: left arm, shoulder, neck, jaw
NSFW: nausea, sweating, fatigue, weak breathing
Some patients will have atypical presentations!
no pain
low-grade fever
pale, cool, clammy skin
hyper/hypotension
How is IHD diagnosed?
history taking, physical examination
investigations
resting ECG
exercise ECG (to induce ischaemia)
Blood tests: HBA1C, FBC, cholesterol profile
CT coronary angiography*
biological markers: troponin, myoglobin, CK
How is IHD treated?
BANS
statin: simvastatin
nitrate: GTN spray (to abort attacks)
dual antiplatelet: aspirin + clopidogrel
Acute (UA/NSTEMI): BMOAN
b-blocker, morphine, oxygen, aspirin, nitrate
Acute STEMI
(if available within 120 min of medical contact) PCI
if not, fibrinolysis (alteplase, streptokinase)
surgical interventions
PCI
CABG (preferred in patients with diabetes, >65 years)
What areas of the heart are represented by the ECG leads?
What is heart failure?
Inability of the heart to deliver blood and thus oxygen at a rate that is commensurate with the requirements of the body
can result from structural/functional cardiac disorder that impairs the heart’s ability to function
when heart begins to fail, other systems try to compensate to maintain CO and perfusion
[sympathetic system activation] BP falls → detected by baroreceptors → sympathetic activation → positively inotropic/chronotropic → CO increases
RAAS system
What causes heart failure?
Ischemic heart disease*
cardiomyopathy (heart walls become thickened, stiff or stretched)
valvular heart disease (AS/MR)
hypertension
alcohol excess
cor pulmonale (disease of lung/pulmonary vessels → pulmonary hypertension → RV hypertrophy → RHF with venous overload, peripheral oedema, hepatic congestion)
anemia, arrhythmias, hyperthyroidism
congestive HF = both sided HF
What are the different types of heart failure?
systolic HF: inability of ventricle to contract properly
diastolic HF: inability of ventricle to relax and fill
acute/chronic
HF reserved ejection fraction
systolic, EF <40%
HF preserved ejection fraction
diastolic, EF > 40%
What are the risk factors for heart failure?
>65, male, obese, people who have previously had an MI, African descent
What are the signs and symptoms of heart failure?
SOFA PC
shortness of breath
orthopnea
fatigue
ankle swelling
pulmonary oedema (due to backflow from decreased CO; produced cough with pink frothy sputum)
cold peripheries
Raised JVP
End respiratory crackles
How is heart failure diagnosed?
Blood test
brain natriuretic peptide (BNP)*
ECG
Transthoracic ECG
wall motion abnormalities
valvular disease
cardiomyopathies
Chest X-Ray
Alveolar oedema
B-lines
Cardiomegaly
Dilated upper lobe vessels
Effusion (pleural)
How is heart failure treated?
Acute HF: OMFG
oxygen, morphine, furosemide, GTN spray
Chronic HF
lifestyle
stop smoking!
eat less salt, optimise weight and nutrition
avoid NSAIDs/verapamil
medical: AABCDD
1st line: ACE-I + B-blocker
2nd line: ARB + nitrate
3rd line: cardiac resynchronization or digoxin
diuretics: furosemide (symptom relief)
What is stage 1 hypertension?
>140/90 mmHg or ABPM >135/85
How does hypertension present?
Usually asymptomatic
Malignant: look for damage in brain, eye, heart, kidney
H(ead)-EYE-PE(cs, heart)R(enal)
Head: cerebral oedema, haemorrhage → stroke symptoms, headache
Eye: papilloedema, cotton-wool spots
Pecs/heart: AHF, aortic dissection → chest pain, dyspnoea
Renal: AKI → haematuria, proteinuria
How is hypertension diagnosed?
If patient comes in with clinic BP > 140/90
recheck BP on 2-3 occasions over next few weeks/months
if persistently high, offer ABPM
if stage 1 diagnosed → do QRISK to decide treatment
if stage 2 diagnosed → start antihypertensive treatment
If patient has malignant hypertension AND signs of papilloedema and/or signs of renal haemorrhage
same day admission
start antihypertensive drug treatment immediately
How is hypertension treated?
First line: ACE-I
Second line: ACE-I + CCB, or ACE-I + Diuretic
Third line: ACE-I + CCB + Diuretic
for diabetics, ACE-I is ALWAYS first line
for black patients, start with CCB as they are not responsive to ACE-I
give CCB before D, unless evidence of oedema/intolerance
ACE-I are CI in pregnancy/if patient is on general anestheia
What is pericarditis?
Inflammation of the pericardium with/ without effusion
Common in young adults (tend to have prior viral infection)
What causes pericarditis?
Causes:
Infectious
Viral (common)
Coxsackievirus
Bacterial
Mycobacterium tuberculosis
Non-infectious
Trauma (common)
Uraemia, MI
How does pericarditis present?
Chest pain
Relieved by sitting forward/ leaning forward
Worsened by inspiration
Fever/ shortness of breath → sign of infection
Pericardial friction rub (high pitched scratchy sound heard loudest on the midline during inspiration)
How is pericarditis investigated?
ECG (diagnostic)
Saddle- shaped ST elevation
PR depression
Do a echo/ chest X-ray if suspect effusion
How is pericarditis managed?
NSAIDs (ibuprofen) + Colchicine
What are the complications of pericarditis?
Cardiac tamponade
What is cardiac tamponade?
Life threatening condition whereby there is an accumulation of fluid in the pericardial space → compression of the heart chambers → decrease in venous return → decrease in filling in the heart → reducing cardiac output
How does cardiac tamponade present?
Beck’s triad
falling BP
rising JVP
muffled heart sound
Pulsus paradoxus (large decrease in stroke volume → systolic blood pressure drops by > 10mmHg on inspiration
How is cardiac tamponade investigated?
Echocardiogram
How is cardiac tamponade managed?
pericardiocentesis (removal of the fluids from the pericardial space)
What is infective endocarditis?
Infection of the inner lining of the heart/ valves (endocardium)
What causes infective endocarditis?
Stahpylococcus aureus (most common → IVDU)
Streptococcus viridans (mouth/ oral sugery, most common→ non-IVDU)
Staphylococcus epidermis (prosthetic valves)
How does infective endocarditis present?
signs of infection (fever, fatigue, loss of appetite)
Splinter haemorrhages
Osler nodes (tender nodules in finger)
Janeway lesions (nodules on palms)
Roth spots (haemorrhage with clear centre on fundoscopy)
*If someone comes in with fever and a new murmur, suspect IE
How is infective endocarditis diagnosed?
Modified Duke’s Criteria
Echo (gold standard)
What is the modified Duke’s criteria?
How is infective endocarditis treated?
Antibiotics (4-6 weeks)
If staphylococcus
(Flucloxacillin + rifampicin + gentamicin)
*MRSA → vancomycin + rifampicin + gentamicin
Not staphylococcus
Benzylpenicillin + gentamicin
Not sure which organism (first line)
FAG (flucloxacillin + ampilicin + gentamicin)
Valvular disease
What is tachycardia?
Fast heart rate >100 bpm
What is atrial tachycardia?
Abnormal P waves
Normal QRS
>150bpm
What is AV nodal re-entrant tachycardia?
Absent P wave
Normal QRS
What is ventricular tachycardia?
No P waves
Regular wide QRS
No T waves
What is bradycardia?
Slow heart rate <60bpm
PR interval between 0.12 and 0.20 seconds
QRS complex <0.12
What is atrial fibrillation?
Chaotic irregular rhythm with an irregular ventricular rate
No P waves
Irregularly irregular QRS
●Stroke risk increase due to static blood in the atria – it pools and it remains still, causing it to clot and embolise
What causes atrial fibrillation?
- Idiopathic
- Hypertension
- Heart failure
- Coronary artery disease
- Valvular heart disease
- Cardiac surgery
- Cardiomyopathy
- Rheumatic heart disease
What are the risk factors for atrial fibrillation?
- 60+
- Diabetes
- High BP
- Coronary artery disease
- Past MI
- Structural heart disease
How does atrial fibrillation present?
- Asymptomatic
- Palpitations
- Dyspnoea
- Chest pains
- Fatigue
- NO P WAVES ON ECG
- Rapid/irregular QRS
- Apical pulse>radial
What is the pathophysiology of atrial fibrillation?
continuous rapid activation of the atria with no organised mechanical action at 300-600bpm.
How is atrial fibrillation treated?
Cardioversion
- Give a LMWH
- Shock with defibrillator
●LMWH = low molecular weight heparin e.g. dalteparin to prevent thromboembolism
What is atrial flutter?
organised atrial rhythm at a rate of 250-350bpm
Sawtooth pattern on ECG (F-waves) - definitive diagnosis
What causes atrial flutter?
- Idiopathic
- Coronary heart disease
- Obesity
- Hypertension
- Heart failure
- COPD
Pericarditis
What are the risk factors for atrial flutter?
Atrial fibrillation
How does atrial flutter present?
- Palpitations
- Breathlessness
- Chest pain
- Dizziness
- Syncope
- Fatigue
How is atrial flutter treated?
Cardioversion
- Give a LMWH
- Shock with defibrillator
- Catheter ablation – creates a conduction block
- IV Amiodarone – restore sinus rhythm
What is the pathophysiology of atrial flutter?
the P wave produces a sawtooth patten with regular conduction to the ventricles
- Wave of contraction around the atria causing the repolarisation of the AV node
What is bundle branch block?
a block in the conduction of one of the bundle branches, so the ventricles don’t receive impulses at the same time
What is right bundle branch block?
Right Bundle Branch Block
MaRRoW
Wide QRS
What causes right bundle branch block?
- Pulmonary embolism
- IHD
- Atrial Ventricular Septal Defect
What is the pathophysiology of right bundle branch block?
- Right bundle doesn’t conduct
- Impulse spreads from left ventricle to right
- Late activation of RV
How is right bundle branch block diagnosed?
ECG
How does right bundle branch block present?
- Asymptomatic
- Syncope/Presyncope
How is right bundle branch block treated?
- Pacemaker
- CRT – cardiac resynchronisation therapy
- Reduce blood pressure
What is left bundle branch block?
WiLLiaM
Wide QRS + notched top
T wave inversion in lateral leads
What causes left bundle branch block?
- IHD
- Aortic valve disease
What is the pathophysiology of left bundle branch block?
- Left bundle doesn’t conduct
- Impulse spreads from right ventricle to left
Late activation of LV
How is LBBB diagnosed?
ECG
How does LBBB present?
- Asymptomatic
- Syncope/Presyncope
How is LBBB treated?
- Pacemaker
- CRT – cardiac resynchronisation therapy
- Reduce blood pressure
What is heart block?
a block at any level of the conduction system in which conduction seizes
What is 1st degree heart block?
PR interval >200ms
Asymptomatic
What is 2nd degree heart block: Mobitz I?
Progressive lengthening of PR interval
One non-conducted P wave
Next PR interval is shorter
Light headedness
Dizziness
Syncope
What is 2nd degree heart block: Mobitz II?
Constant PR
Occasional non-conducted P-waves
Wide QRS
What is 2nd degree hear block: 2:1?
Two waves per QRS
Normal consistent PR intervals
SOB
Postural hypotension
Chest pain
What is 3rd degree heart block?
P waves and QRS at different rates
Dissociation
Abnormally shaped QRS
Dizziness
Blackouts
Permanent pacemaker
IV atropine
What causes heart block?
- Athletes
- Sick sinus syndrome
- IHD – esp MI
- Acute myocarditis
- Drugs
- Congenital
- Aortic valve calcification
- Cardiac surgery/trauma
How do you investigate heart block?
ECG
How do you treat heart block?
Cardioversion
- Give a LMWH
- Shock with defibrillator
- Catheter ablation – creates a conduction block
- IV Amiodarone – restore sinus rhythm
What is stage 2 hypertension?
>160/100 or ABPM 150/95
What is malignant hypertension?
>180/110
What causes hypertension?
Primary: unknown
Secondary: renal disease/pregnancy/endocrine diseases/coarctation/drugs and toxins
