Coronary Artery Disease Flashcards
What are the inferior, anterior, and lateral leads and which blood vessels supply those areas?
II, III, aVF - supplied by RCA
V1-V4 - supplied by LAD
I, aVL, V5-V6 - supplied by circumflex
What can a new LBBB in a patient presenting with chest pain be suspicious for?
STEMI
Of the acute coronary syndromes, which are more common?
NSTEMI and unstable angina more common than STEMI
Where is a plaque particularly vulnerable to rupture?
The shoulder
When during the day is acute MI most likely to occur?
Between 6am and noon
Peak incidence in first three hours after awakening
What’s the main goal of treatment for patients presenting with a STEMI?
Achieve reperfusion within 120 minutes - optimally within 60
What are the options for reperfusion in a STEMI?
PCI - primary coronary intervention - door to balloon time of less than 90 minutes
Thrombolytic therapy - door to needle time within 30 minutes
What are absolute contraindications to thrombolytic therapy?
Active internal bleeding
Recent (<1 mo) GI bleeding
Recent serious trauma, including prolonged CPR
What are relative contraindications to thrombolytic therapy?
Severe hypertension (s>200, d>110) Recent minor trauma Hemostatic defect Severe hepatic or renal disease Diabetic hemorrhagic retinopathy
What are 3 major factors to consider when crossing between PCI and thrombolytic therapy?
Availability of PCI capable lab that can achieve door to balloon of 90 minutes - if not, thrombolytic, then transfer later
Bleeding risk or contraindications for thrombolytic - use PCI
experience of operator doing PCI
What are acute medications commonly given after MI?
Aspirin Other antiplatelet agents (clopidogrel) Heparin Nitrates Beta blockers - but can precipitate cardiogenic shock in tachycardia, heart failures or large infarctions - don't use ACE inhibitors - if normal creatinine and not hypotension Statins Admin of oxygen
Which two drugs have been proven in long term studies to reduce mortality following MIs?
Beta blockers
Captopril (ACE inhibitor)
What is the pathophysiology of NSTEMI or unstable angina?
Periodic platelet plugging and platelet mediated coronary arterial vasoconstriction occur after which portions of plug break off and are swept away, partially restoring perfusion
What is the medical therapy for NSTEMI and unstable angina?
Reperfusion with thrombolytics not beneficial
Emergent coronary intervention not required
Invasive management reduces morbidity but not mortality and is warranted if: older than 65, marked ST and T alterations, enzyme evidence of myocyte necrosis –> angiography followed by revascularization (catheter based or surgical)
Also indicated if patient has spontaneous or inducible ischemia despite adequate medical therapy
In addition to coronary revascularization, what does therapy of unstable angina or NSTEMI center on?
Platelet inhibition (clopidogrel, aspirin) Thrombin inhibition (LMWH) Control of oxygen demands (beta blocker) Prevention of vasoconstriction (nitroglycerin)
