IHD Flashcards
Prasugrel is contraindicated in 3 occasions?
- Older than 75
- Haemorrhagic stroke - massive increase in risk
- Weight <60kg
Risk factors for IHD? (11)
- HTN
- Smoking
- DM
- Cholesterol
- FH (especially 1st degree relatives <60)
- Obesity
- Lack of exercise
- Erectile dysfunction (often precedes IHD symptoms, marker of endothelial dysfunction)
- Homocysteine
- COX2 or NSAIDs
- OCPs or premature onset of menopause
While at R, what questions / investigations can you ask about adequate risk factor control? (6)
- BP – salt restriction??
- Smoking cessation
- HBA1C
- LDL (<1.8), Cholesterol (<4)
- Weight loss + exercise
- Whether NSAIDs / COX2 are consciously avoided or used liberally
IHD: Complications to ask? (5)
- Heart failure
- Arrhythmias – brady + tachy (Inferior / posterior MI → AV node dysfunction → heart block, VT/VF)
- Embolic events – e.g. stroke from LV thrombus
- Further heart attacks / ACS
- Whether surgery was required for e.g. acute MR or infarc-related VSD
Patient had CABG and has no radial pulse - What does this mean?
•Patient may have had CABG using radial artery
Approach to acute STEMI mx
- Activate the Cathlab
- If unavailable, consider thrombolysis
- Start DAPT – second choice depends on situations
- Planned PCI → tigarelor (180mg) or prasugrel (60mg) loading dose if no CI (prior stroke/TIA, 75yo or older, weight <60kg) – if so Clopidogrel 600mg
- Thrombolysed → clopidogrel 300mg (<75) or 75mg (>75yo)
- Not for thrombolysis → ticagrelor 180mg loading
•Heparin infusion (consider clexane if PCI or thrombolysis not being performed)
Why do you need to Cath the patient who was already thrombolysed?
•Even if thrombolysed, usually PCI required as <60% of patients would have definite opening of infarct-related artery
When would you thrombolyse STEMI patient? (2)
- <12 hours since onset + no absolute contraindications + PCI cannot be performed within recommended time (1A) – usually 2-3 hours
- Symptomatic patient who present after 12 hours (but <24h) when PCI not readily available (2A)
- Tenecteplase or Reteplase is recommended instead of alteplase (2B)
- Regardless, early transfer to PCI centre to decided whether rescue vs. elective PCI is needed.
Approach to UA/NSTEMI?
•DAPT
- For PCI → Ticagrelor 180mg or prasugrel 60mg
- If >75yo, stroke/TIA, <60kg → clopidogrel (300-600mg depending on bleeding risk, thrombocytopaenia…etc) or ticagrelor 180mg
- Not for PCI → Ticagrelor 180mg
•Anticoagulation
- Heparin infusion if PCI planned within 4-48 hours
- Not for PCI → Clexane, at 1mg Kg 12 hourly, dose adjust if CrCl <30 → 1mg/kg every 24 hours
The use of ticagrelor or prasugrel (P2Y12 inhibitor) is based on what trials?
- TRITON-TIMI 38 trial (prasugrel vs. clopidogrel) – HR 0.81 (CV death, non-fatal MI, non-fatal stroke) - But more bleeding events → RF identified are TIA/Stroke, age 75 or above or weight <60kg
- PLATO trial (ticagrelor vs. clopidogrel in ACS) - HR 0.84 at 12 months (death from vascular events, MI or stroke)
- No difference in major bleeding events (11.6% vs 11.2%)
- Associated with higher rate of major bleeding not related to CABG (4.5% VS. 3.8%)
Summary: both ticagrelor & prasugrel are better, but higher risk of bleeding if risk factors present (<75yo, weight <60kg, TIA/stroke).
Is there any other therapy you would consider for those with very high risk of ischaemic event of complication of PCI (e.g. large thrombus burden seen in angiogram)?
- Consider Glycoprotein IIb/IIIa inhibitor (abciximab, tirofiban or epti-fiba-tide) – Grade 2C
- Argument for this is stronger if patient did not have ticagrelor or prasugrel
- However in most patient it is NOT recommended if oral DAPT has been given (1B) so talk to cardiologist
What is your approach to investigating symptomatic patient with IHD? (SOB/CP)
- Assess infarct size, complications and presence of further ischaemia
- TTE: to look for infarct size (RWMA), LV function and complications of infarct (e.g. MR, LV thrombus, infarct related VSD)
- Stress test: inducible ischaemia
- MIBI: inducible ischaemia + viability
- Angiogram
3 indications to consider CABG?
- Diffuse TVD
- Left main disease
- Tight proximal LAD (before 1st diagonal branch)
Non-pharmacological Mx – secondary prevention? (9)
- Cessation of smoking
- Weight loss
- Exercise
- Mediterranean diet (+statin)
- BP control: salt and fluid restriction (+ACEi/BB)
- Diabetes control
- Stress management
- Cardiac rehab
- No sexual intercourse for 1 month following event
Total duration of DAPT following PCI? in following situations
Default
No bleeding risk
High bleeding risk
Duration of single antiplatelet
- Individualised depending on bleeding vs. ischaemic risk
- Regardless of stent type, recommended for at least 6-12 months
- In free of moderate (needing transfusion) or severe bleeding risk → at 12 months review → most advocates additional 18-24 months of DAPT
- Most will favour at least 3 months of DAPT where bleeding risk is very high
- Some will consider as short as 1 month
- Single antiplatelet recommended indefinitely, however, single agent anticoagulation (warfarin, NOACs) would be a suitable alternative if they were already on it for e.g. AF.
Is there any tool that you can use for stratification to decide on the duration of DAPT following PCI in patients with bleeding risk to decide whether to continue further than 12 months of DAPT?
DAPT score – based on DAPT trial (2014)
- Based on traditional ACS risk factors (age, active smoking, DM) and;
- Stent type, whether vein graft was stented
- Prior MI/PCI or MI at presentation, HF, LVEF <30%
Low score (<2) → risk of bleeding > risk of ischaemia ⇒ Harm > benefit with prolonged therapy beyond 12 months
High score (=>2) → risk of ischaemia > risk of bleeding ⇒ Benefit > harm with prolonged DAPT beyond 12 months (18 additional months)
Still need external validation, hence clinical judgement still applies
When would you choose BMS over DES? (3)
• 2nd generation DES preferred then BMS in most cases due to lower need for target vessel revascularization + better safety profile
However, in following occasions BMS is generally more preferred
- Patients who require non-cardiac surgery within four to six weeks of PCI (T&O says if surgery planned within 6-12 months).
- Patients with active bleeding at the time of PCI or those at very high risk of bleeding while taking DAPT.
- Patients unlikely to comply with antiplatelet therapy for at least one month.
Difference between BMS and DES – how are they differ in terms of re-stenosis / thrombosis risk?
BMS
- Increased in-stent restenosis
- Decreased late stent thrombosis
DES
- Decreased in-stent restenosis ⇒ as drugs are anti-neoplastic and prevent migration of SMC into the lumen of vessels (causing restenosis)
- Increased late stent thrombosis
DDx for very early angina following CABG? (5)
- Graft spasm – e.g. mammary artery spasm
- Thrombosis of SVG
- Grafting wrong vessel
- Grafting to wrong area (i.e. proximal to area of stenosis)
- Residual distal disease that is not suitable for grafting – so read the operation notes
Is Aspirin indicated following CABG?
- Yes – shown to prolong graft survival
- Patients with severe diffuse disease are often given DAPT
Would you always consider stenting stable angina patient with single or double vessel disease?
- Optimal medical therapy is just as good as angioplasty in terms of prognosis (except Left main or proximal LAD disease)
- However, angina is better controlled by angioplasty
- Benefit compared with OMT when FFR (fractional flow reserve) during angiogram is suggestive of ischaemia (<0.75 or <0.8)
So to a significant degree, patient preference is important.
What do you mean optimal medical therapy? (6)
- Aspirin + / − clopidogrel (for 1 year post ACS)
- Statin – target LDL 1.8 mmol / L
- ACEI or ARB at maximum tolerated dose
- Beta-blocker – heart rate down to < 70
- Hypertension treated to < 130 / 80
- Exercise 3 times a week at least for > 150 minutes / week
STEMI or NSTEMI in patient already on NOAC
- Difficult Mx problem
- Options are DAPT + NOAC vs. Clopidogrel + NOAC or NOAC only
- Depending on risk of bleeding vs. risk of recurrent ischaemia
Syntax trial?
•PTCA vs. CABG in multivessel and LM CAD
- Same survival
- Increased procedures with PTCA
- Worse outcome in DM with PTCA
- Low Syntax score do equally well
- High Syntax score do much better with CABG
•Syntax score is an assessment of the severity and location of coronary disease used to predict risk of PCI and CABG surgery
