Coronary Artery Disease Flashcards
Angina — definition / criteria ?
left thoracic or retrosternal pain or tightness
associated with physical or psychological stress
completely reversible at rest or with nitroglycerine
1+: thoracic pain, 2+: atypical angina, 3+: typical angina
stable angina — MRI findings ?
stress perfusion defect
wall motion irregularities (at rest or at stress)
acute coronary syndrome (ACS) — definition and facts ?
STEMI — myocardial necrosis with specific ECG changes
NSTEMI — myocardial necrosis without specific ECG changes
unstable angina — myocardial ischemia without necrosis
acute coronary syndrome (ACS) — MRI findings ?
wall motion abnormality
perfusion defect
focal cardiac edema
subendocardial late gadolinium enhancement (LGE)
acute coronary syndrome (ACS) — role of MRI (detailed) ?
- gold standard in assessment of global and regional LV function
- detection of ischaema (perfusion defect)
- detecting scar tissue / myocardial cell membrane destabilisation - LGE
- myocardium at risk (mismatch edema/LGE)
- prognosis / risk stratification (myocardial salvage, microvascular obstruction, haemorrhage)
- exclusion of DDx eg. myocarditis or Takotsubo
- discrepancy to clinical symptoms eg. spontaneous revascularisation, coronary vasospasm
unstable angina, chest pain without ECG changes or elevated troponin
I3 Indication: stress MRI in stable patients with low or intermediate risk
NSTEMI
I2 Indication: exclude DDx e.g. myocarditis
U Indication: (TEI, area at risk, microvascular obstruction)
STEMI
I3 Indication: risk stratification in early phase (“myocardial salvage”, microvascular obstruction, myocardial haemorrhage)
acute coronary syndrome (ACS) — epidemiology ?
incidence 100-300/100000 per year
15% STEMI, 40% NSTEMI, 45% unstable angina
10-20% of all patients presenting with thoracic pain
acute coronary syndrome (ACS) — aetiology / pathophysiology ?
coronary arteriosclerosis — coronary plaque formation
imbalance between oxygen supply and demand -> ischaemia
plaque rupture -> coronary thrombosis / occlusion
coronary emboli
coronary vasospasm
acute coronary syndrome (ACS) — differential diagnosis (DDx) ?
cardiac origin — e.g. myocarditis, Takotsubo
non-cardiac vascular origin — aortic dissection, pulmonary embolism
pulmonary origin — pneumothorax, pneumonia
gastrointestinal origin — GERD, oesophageal rupture
musculoskeletal origin
coronary embolus / thrombosis — presentation ?
present as acute coronary syndrome (ACS) with elevated troponin
-> NSTEMI, STEMI
coronary thrombosis — aetiology ?
plaque rupture ~70% coronary vasospasm cocaine abuse heparin induced thrombocytopenia antithrombin III deficiency hormone therapy
coronary embolus — aetiology ?
atrial fibrillation
cardiomyopathy
valvular disease
septic or paradoxical emboli (rare)
coronary embolus — diagnosis ?
usually well defined (round) filling defect on ICA
usually no other arteriosclerotic changes
usually no causative lesion / plaque after thrombectomy
presence of risk factors
coronary embolus / thrombosis — role of MRI?
assessing consequences / outcome
volumes / function
LGE (TEI — transmural extent of infarction)
myocardial area at risk / myocardial salvage
microvascular obstruction, myocardial haemorrhage
coronary embolus / thrombosis — therapy ?
- thrombectomy and stent placement
- surgery
coronary embolus — prognosis ?
acute mortality 3-6%
~10% repeated embolic events within 5 years
~27% other relevant cardiogenic or cerebrovascular complications
~28% of patients with cardiac embolus die within 5 years vs ~7.6% with MI of other origin
coronary thrombosis — prognosis ?
acute mortality 3-6%
after multifocal coronary thrombosis
~ 18% develop heart failure within 2 years
~ 4% develop an additional MI within 2 years
coronary embolus / thrombosis — complications ?
cardiogenic shock
death
coronary aneurysm — definition and facts ?
> 150% of normal lumen
<50% of vessel length otherwise coronary ectasia
true aneurysms include all three vascular layers
coronary pseudo-aneurysms are rare (include one or two layers)
coronary aneurysms — aetiology ?
arteriosclerosis
congenital
infection
inflammation (Kawasaki syndrome)
Kawasaki syndrome — definition and facts ?
coronary vasculitis of unknown origin leading to coronary aneurysms
Stress CMR - advantages ?
- really non-invasive
- high spatial resolution (vs NM)
- high temporal resolution (vs CT)
- high contrast resolution (vs CT and NM)
- less artefacts (vs NM)
- structural and functional information
- allows quantification
- special issues: multi-vessel-disease (MVD), LBBB, women
Ischaemia detection with stress CMR - evidence ?
- IMPACT1 -> stress CMR > SPECT
- IMPACT2 -> stress CMR > SPECT
- CEMARK -> stress CMR > SPECT
- CEMARK2 -> stress CMR > NICE guideline care
Viability definition ?
- preserved ED wall thickness
- preserved contractile reserve
- present but maybe reduced perfusion
- preserved cell metabolism
- functional intact (recovered) myocardium after revascularisation
Stunned myocardium - definition ?
- usually after acute ischaemic event
- impaired function
- preserved contractile reserve
- preserved perfusion
- preserved metabolism
- no remodeling
Hibernating myocardium - definition ?
- usually in case of chronic ongoing ischaemia
- impaired function (RWMA)
- not fully preserved contractile reserve
- present but reduced perfusion
- normal metabolism
- no remodeling
Acute coronary syndrome - risk stratification ?
- infarct size
- transmurality (TEI)
- peri-infarct zone (independent predictor)
- microvascular obstruction (MVO) - associated with remodeling
- haemorrhage - associated with remodeling
- area at risk (AAR)
- right ventricular infarction - worse prognosis
Role of CMR in acute coronary syndrome (short) ?
- detection / confirm diagnosis
- age
- stratifying risk (TEI, MVO, haemorrhage, RVI)
- predicting response to therapy
- detecting complications
- differential diagnosis
