2ECG - Acute Coronary Syndromes Reviewing ECG for changes related to ACSECGs evolve over time, during and after ACOECG interpretation linked to management decisionsSystematic approach to reading ECGsPrinciples discussed and examples of Macstrak ECG data capture
3ACS - early assessment ECG can provide answers to: Acute Coronary Occlusion (ACO)Is the vessel open or closed?How long was it closed?What territory is at risk?Threatened ACO (TACO)Is there a risk of an occlusion event?Consequences of an occlusion event?
4ACO - early assessmentECG assessed in conjunction with history at presentation – e.g. prolonged chest pain?Artery open/closed? ST elevation means closedDuration of occlusion:ST resolution artery may have openedQ waves present long duration of closureST elevation shape convex early occlusionST elevation shape concave late occlusion
5ACO - early assessment Each lead looks at specific area of myocardium Grouped leads represent heart muscle territoryTerritory Leads Coronaryinferior II,III,aVF RCA or Circanterior V1-V LADlateral I,aVL Diagonal or OM apical V5-V6 LADposterior V7-V9 CircInferior STUp requires a right sided ECGRV V4R RCA
7TACO - early assessment TACO (Threatened ACO) arteries have unstable plaque or partial occlusion that is at risk for complete closureRisk of occlusion event is greater if:pain is cardiac; troponins +ve; ST’s, T’s changingpain at presentation or recentprolonged > brief episodes (>2 min)pain present despite therapy (ASA, clopidogrel, heparin, GP2b/3a inhib., IABP)
8TACO - early assessment Consequences of occlusion event:What is the territory at risk ?anteriorlarge inferior with RV involvementprevious infarction – Q wavesClinical assessment during ischemiahypotension, pulmonary edema
9ACS - ECG interpretation Approach:Rhythm:Is it NSR? If not – intervention for brady/tachy?Is morphology valid?P wave - in sync with QRSQRS width > RBBB V1- rSR, V6 - RSLBBB V1- QS, V6 - RR
10ACS - ECG interpretation Approach:The ECG can be used to look for ACS changes when none of the following conditions are present:LBBBPacedVTAccelerated idioventricular rhythm (AIVR)
11ACS - ECG interpretation Approach:Morphology:ST’s - Up or down- ST Up - 1 mm, except V1-4 2 mm- ST Down 1 mm (flat)Q’s wide (one box)T’s - inversion (where QRS is positive)V4R - ST Up - 1 mmV7-V9 - ST Up - 1 mm
19These are the pictures from the patient’s PCI These are the pictures from the patient’s PCI. The top picture shows an acute total occlusion of the RCA. The bottom, shows restored blood flow to the area supplied by the RCA.
20Patient presented with a history of on and off chest pain yesterday that became continuous and more intense about 3 hours ago.
21Using the approach presented P wave one with QRS QRS width 0.12 Will morphology be valid? YESNote: First three beats are ectopic atrial – not NSR but morphology is valid