Block 31 Week 1 Flashcards
investigations for chest pain?
- ECG
- troponin
- lab tests
History for chest pain that suggests cardiac pain?
- central crushing/ heavy pain
- sudden onset
- clammy
MI RF?
- FHx
- hypertension
- diabetes
- smoking
what can cause inc troponin?
- loss of BS
- PE can put strain on R side of heart -> damage
- inflammation: pericarditis e.g.
PE?
- PE: pain more often pleuritic
- likely to be SOB
Myocarditis?
- Myocarditis pain is often positional
- can be pleuritic
- likely to be ECG changes
heart muscle damage: haemodynamic strain?
aortic dissections. sepeis, blood loss, burns, extreme exertion
heart muscle damage: very fast heart rate?
fast AF, VT, VF, SVT (palpitations in history)
HM damage: strain within heart?
aortic stenosis, obstruction in hypertrophic cardiomyopathy
what is associated w chest pain?
aortic stenosis
Takotsubo’s cardiomyopathy?
- Takotsubo’s cardiomyopathy: stressful situation which leads to a ballooning of the apex of the heart -> sig troponin rise and chest pain
HM damage: trauma to heart?
e.g. car collision, valve or bypass surgery
type 2 MI?
- MI secondary to another process e.g. sig sepsis - type 2 MI
Sepsis?
pyrexial, high white cell count etc
severe aortic stenosis?
ejection murmur
mechanisms of blood loss in the heart?
- thrombus formation on underlying diseased coronary arteries - atheromatous plaque
- coronary artery spasm - transient or peristent vasospasms
- spontaneous coronary artery dissection
coronary angio vs echocardiogram?
- coronary angiogram - visualisation of coronary arteries (confirms diagnosis)
- echocardiogram - asesss function of heart muscle
NSTEMI vs STEMI?
- NSTEMI: incomplete occlusion
- STEMI: restore blood flow within 12 hours
cardiac ischaemic pain?
- central
- crushing
- heavy
- tight band
- related to exertion
- relieved by GTN within minutes
descriptors that make u think its not cardiac ischaemic pain
Features assoc w cardiac pain?
- clammy
- nauseaous
- SOB
- light headed
- collapse
- palpitations
pain history?
- how long
- constant/ intermittent
- when was it worse
exacerbating factors for the pain?
- breathing
- food
- exertion
- position
cardiac differentials for chest pain?
- myocarditis
- takotsubos
- heart failure
- pericarditis
- ACS
- airtic dissection
- severe aortic stenosis
resp differentials for chest pain ?
- pleuritis
- pneumothorax
- PE
- pulm hypertension
- asthma exacerbation
GI differentials for chest pain?
- GORD
- oeseophagitis
- oeseophageal spasm
- gastritis
- gastric ulcer
MSK differentials for chest pain?
- rib fractures
- costochondritis
other differentials for chest pain?
- panic attacks
- somatisation
ripping tearing severe central chest pain radiating to the back ->
aortic dissection
sharp positional pain worse when lying flat and eased when sitting ->
pericarditis, myocarditis
central, heaving crushing pain worse on exertion, radiation to jaw or arms, clammy, sweaty, nausea ->
MI
Sharp pain, worse on inspiration, SOB, D dimer positive ->
PE
Central crushing pain Ix
angina?
- lumen diameter reduced by around 50% so coronary blood flow is unable to respond to an inc in metabolic demand
NSTEMI/ unstable angina
- resting flow affected when lumen diameter reduced by ~80%
STEMI?
- sudden complete occlusion
Ix for SOB + chest pain
angina Ix results
- ECG can have ST depression and/or T wave inversion
- troponin negative
NSTEMI Ix results?
- ECG can be normal or have ST depression and or T wave inversion
- troponin positive
STEMI results?
- troponin positive
GI bleed and type 2 MI?
- massive GI bleed can precipitate MI from hypovolemia and myocardial hypoerfusion
Causes of MI
angina pain?
- chest pain on exertion
- less severe partial occlusion w plaque
unstable angina characteristic pain?
- chest pain on progressively less exertion and now episodes at rest
- partial occlusion
- increasing plaque and thrombus
NSTEMI pain?
- sudden onset chest pain at rest
- partial occlusion
STEMI pain?
- sudden onset chest pain at rest
- total occlusion
- plaque rupture and thrombus
types of MI?
Angina and NSTEMI can have ST depression/ T wave inversion
differentials for angina/ MI?
- coronary artery spasm
- SCAD
- Takosubo’s
X rays?
- different tissues attenuate the beam to varying degrees depending on atomic constituents
- The image starts all white. If x-rays reach the detector that part of the image turns black.
Why are bones white on X ray?
- bones have a high atomic denstity so white as lots of X rays are abs so only a few pass through
heart on an XR?
Lungs on an XR
Consolidation?
- radiological sign
- alveoli and small airways fill up with material
- Larger airways remain air-filled giving rise to an ‘air bronchogram’ sign
What can give rise to consolidation on a CXR (3)
- Pus (e.g. in pneumonia)
- Fluid (e.g. in pulmonary oedema)
- Blood (e.g. in traumatic contusions)
e.g. of consolidation
air bronchogram?
- black areas within the area of inc density
- these are larger airways that remain air filled so you can see them clearly
- key part of consolidation
lung collapse?
- can be partial - collapse of one lobe of the lung
- or total which is collapse of an entire lung
lung collapse - compression?
(e.g. due to fluid or air in the pleural space around the lung in an effusion or pneumothorax respectively)
Lung collapse - obstruction?
- or obstruction of a bronchus e.g. by tumour or an inhaled foreign body (where the lung distal to the obstruction will collpased)
Lung collapse in a child?
- lung collapse in a child is often due to inhalation of a foreign body or mucus obst in asthma
lung collapse in an adult?
- Lung collapse in an older person raises concern for an underlying tumour (e.g. primary lung cancer) and further investigation is often required (e.g. with CT and/or bronchoscopy).
main features of collapse?
- area of homogenous increased density without air bronchograms (vs consolidation).
- There are no air bronchograms as all the airways are collapsed distal to the obstruction and do not contain air.
sail sign?
- left lower lobe collapse
- creates triangle of increased density behidnt he heart
- makes it look like there are 2 heart borders
CT of left lower lobe collapse?
pleural effusion?
- accumulation of fluid in the pleural space
- appears as an area of homogenous increased density (whiter than the normal lungs)
pleural effusion CXR?
- If the CXR is taken with the patient sat up or stood up, the fluid will settle dependently and will obscure the diaphragm.
bilateral vs unilateral Pleural effusion?
- It can be unilateral (typical in malignant causes) or bilateral (typical in heart failure)
pleural effusion x ray
P effusion causes
V large pleural effusion
- an effusion as large as this is v concerning for a malignant cause like lung cancer, mesothelioma etc
- complete collapse of the left lung
- signs of colume loss in the left hemithorax - trachea is pulled to the left and the D is pulled up - stomach bubble seen high on left side
- massive left pleural effusion
- this is bc there are signs of increased volume in the left hemithorax due to the fluid - trachea and heart are shifted away to right side
How to differentiate large effusion from collapse?
- Working out whether there is volume loss or increased volume in the hemithorax is key to differentiating between a large effusion or collapse.
PLC on CXR?
- primary LC appears as a solid mass on CXR usually
- This will usually not contain air bronchograms (like consolidation does)
- Sometimes you will not see the actual mass but will see the result of the mass such as collapse of the lung or one lobe of the lung, or a pleural effusion.
CXR vs CT for lung cancer
- CXR usually done as first Ix as it is readily available and involves little radiation exposure
- CT is more sensitive for lung cancer than CXR - so if high clinical suspicion do a CT
lung cancer CXR?
Causes of PF
Severe fibrosis scan
cardiomegaly
- normal cardiothoracic ratio: 50%
HF features on CXR?
- cardiomegaly
- pleural effusions (due to fluid leak into the pleural space)
- septal thickening - due to fluid leak into the intersitial space
- consolidation due to fluid leak into the alveoli
HF signs are usually?
bilateral
HF CXR ?
Summary of HF CXR?
- cardiomegaly,
- small pleural effusions,
- some septal thickening
- and bilateral consolidation
CHD incidence?
- 1 in 6 male deaths and 1 in 9 female deaths
- most common cause of death in under 75s in the UK
ACS cause?
- ACS are caused by rupture of lipid rich atheroma plaques.
- -> platelet adhesion
- activation and thrombin activation with resultant occlusion / partial occlusion of the coronary artery and ischaemia/infarction.
stable angina cause?
- stable angina is usually caused by plaques which sig reduce lumen of the artery so ischemia occurs on exertion
occluded artery image
history taking?
- the character, duration, severity and radiation of the pain.
- relieving/exacerbating factors
- associated symptoms (eg nausea)
- and consider differential diagnoses (eg varying with respiration - pleurisy or pericarditis, upper GI symptoms such as indigestion, weight loss).
PMH/ RF for CAD?
- previous vascular disease
- RF for coronary artery disease - smoking, diabetes, obesity, hypertension, FHx
Co-morbidities that can cause a contra-indication for ACS meds?
- Any potential co-morbidities that might indicate a contra-indication to the medications required for ACS treatment eg recent GI bleed when taking aspirin therapy
cardiac examination
- haemodynamic status - pulse, BP, resp rate, O2 sats
- signs of cardiac failure:
- crackles in the lung bases
- elevated JVP
- gallop rhythm
- peripheral oedema
- underlying cardiac disease e.g. murmur of aortic stenosis
Ix of CAD?
- make the diagnosis (ECG and cardiac enzymes)
- exclude exacerbating factors (eg anaemia)
- identify complications (eg pulmonary oedema on CXR)
- evaluate left ventricular function (echocardiography)
- in some cases exclude other diagnoses (eg amylase-acute pancreatitis)
meds for CAD?
Antiplatelets and statins
Mx of CAD?
- meds - antiplatelets, statins
- pain relief e.g. opiates + anti-emetics
- nitrates - sublingal GTN or IV infusion
- consider oxygen
STEMI Mx?
- PCI
- aspirin 300mg stat
- proximitiy to defibrillator requiredc
complications of AMI?
eg: arrhythmia, cardiac arrest, LV failure, recurrent ischaemia
All AMI ppts should undergo assessment of?
LV function prior to discharge - echo
PPCI?
- aims to restore blood flow by using a soft wire to cross the occluded coronary segment and perform intervention to open the narrowing
- thrombus may be extracted and procedure relies on pharm - anti-thrombotic and anti-platelets to treat the thrombus
What happens after PPCI?
- stent inserted to maintain vessel lumen then dual anti-platelet therapy required
nstemi - early Tx w?
- early treatment with aspirin, statin, and low molecular weight heparin to reduce the risk of AMI/death
- second anti-platelet agent should also be given (eg clopidogrel, ticagrelor or prasugrel)
NSTEMI - consider IV?
- Consider IV glycoprotein IIb/IIIa inhibitor for high risk/ unstable ppts
NSTEMI - anti-ischaemics?
BBs, nitrates (CCBS, nicorandil, ivabradine, ranolazine)
ACS Tx pathway
Ix for MI?
- Identify risk factors for atheroma
- eg glucose and cholesterol
- Identify factors that exacerbate angina
- eg haemoglobin (anaemia), thyroid function (hypothyroid / thyrotoxicosis)
CAD likelihood
Identify cardiac abnormalities
- ECG (often normal in patients with angina)
- Echocardiogram if needed (eg suspicion of LV dysfunction, cardiac murmur)
rapid access chest pain clinic?
- those with recent onset angina should be seen within 2 weeks of referral in a rapid access chest pain clinic
Tx of angina - anti-ischaemics?
e.g beta-blockers, calcium channel blockers, nicorandil, ivabradine, ranolazine, long-acting nitrates
angina - Additional treatment to reduce the risk of MI/death?
- aspirin, statins
- management of diabetes and hypertension, smoking cessation, encourage exercise (assuming symptoms are stable)
angina - symptoms despite medical therapy
- those w ongoing symptoms despite medical therapy should be considered for revascularization - either PCT or CABG
EA of heart?
- EA starts at SA node
- spreads through atrium to AV node where it is delayed
- travels down BoH
- down right and left bundle branches
P wave?
electrical signal from SA node spread through atria and cause them to depolarise
PR segment =
time signal travels through AV node
Q wave =
depolarisation of intraventricular septum
R wave =
depolarisation of bulk of ventricle
S wave =
last phase of ventricular depolarisation
ST segment?
plateau in myocardial action potential (when ventricles contract and pump blood)
T wave?
ventricular repolarisation
Segments and waves on an ECG
Q R and S waves
Basic ECG
Segment on an ECG?
Lines that connect waveforms
Which segment is used as the baseline on an ECG?
- TP segment is the least affected by pathology so can be used as the baseline within the ECG
QRS interval?
- QRS = duration of QRS complex alone, should be less than 120ms long
P-R interval?
- PR interval = 120-200ms
- P wave and PR segment