Advanced ecgs
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![Page 1: Advanced ecgs](https://reader036.fdocuments.in/reader036/viewer/2022062401/58a1f26e1a28ab531e8b70f5/html5/thumbnails/1.jpg)
Alastair Jones
ADVANCED ECGsBeyond the basics…
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Quiz Q1
✤ 55 year old man presents with central crushing chest pain.
✤ Comment on the ECG and what is you treatment plan?
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Quiz Q1
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Quiz Q2
✤ 78 year old diabetic man. Previous MI. Presents with sudden onset SOB and an odd feeling in chest.
✤ Comment on the ECG and what is you treatment plan?
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Quiz Q2
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Quiz Q3
✤ 45 year old male. Brought in by wife after an episode of severe indigestion last night. Now symptoms free. Insists he’s fine and wants to go home. Thinks his wife is worrying unnecessarily.
✤ Obs fine. Bloods normal. Trop negative.
✤ Comment on the ECG and what is your management plan?
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Quiz Q3
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Quiz Q4
✤ 78 year old lady who presents with ischaemic chest pain.
✤ Comment on the ECG.
✤ How can you confirm your diagnosis and what is your management plan?
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Quiz Q4
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Quiz Q5
✤ 20 year old student. Brought in after collapse.
✤ Went to feel lightheaded and then blacked out for a few seconds.
✤ Not happened before. Now feels fine and wants to go home.
✤ Comment on his ECG and what would you tell him?
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Quiz Q5
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Quiz Q6
✤ VT OR SVT?
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Quiz Q6
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Elevation in aVR
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Elevation in aVR
✤ Single lead - significant?
✤ Yes. STE in aVR implies lesion of the left main coronary artery
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Elevation in aVR✤ STE in aVR itself of more than 1.5 mm carries a 75%
specificity of LMCA and ~75% mortality!
✤ STE in aVR + avL -- 90% specificity AMI
✤ STE in aVR + V1 -- suggestive either prox LAD or LMCA occlusion but
✤ STE in aVR > V1 -- more suggestive of LMCA
✤ The significance of STE in aVR is dubious in the presence of BBB.
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Sgarbossa Criteria
✤ Or how to detect AMI in LBBB
✤ ST elevation ≥1 mm in a lead with upward (concordant) QRS complex - 5 points
✤ ST depression ≥1 mm in lead V1, V2, or V3 (concordant) - 3 points
✤ ST elevation ≥5 mm in a lead with downward (discordant) QRS complex - 2 points
✤ ≥3 points = specificity of 98% and sensitivity of 20% (10 paper meta-analysis of 614 patients)
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Sgarbossa Criteria
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Sgarbossa Criteria
✤ Only one lead required BUT the significance of elevation in aVR is no longer certain.
✤ Serial / old ECG’s can also help
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Wellens’ Syndrome✤ Wellens’ syndrome is a pattern of inverted or biphasic T
waves in V2-3 (in patients presenting with ischaemic chest pain) that is highly specific for critical stenosis of the left anterior descending artery.
✤ Patients may be pain free by the time the ECG is taken and have normally or minimally elevated cardiac enzymes; however, they are at extremely high risk for extensive anterior wall MI within the next 2-3 weeks.
✤ Type 1 Wellens’ T-waves are deeply and symmetrically inverted
✤ Type 2 Wellens’ T-waves are biphasic, with the initial deflection positive and the terminal deflection negative
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Wellens’ Syndrome - Type 1
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Wellens’ Syndrome - Type 2
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Wellen’s Syndrome✤ Wellen's criteria is not dependent on ST changes, just the T
inversion!
✤ VERY worrying...Signifies critical LAD stenosis!
✤ 100% of 180 patients with the pattern having >50% stenosis of the left anterior descending coronary artery (mean = 85%), with complete or near complete occlusion in almost 60%.
✤ Likely to need a cath lab rather than medical therapy...
✤ Should be investigated urgently even if now asymptomatic!
✤ BUT - young children and especially female up to 40 years, may have normal variant of T inversion (the juvenile pattern).
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Posterior MI
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Posterior MI
✤ Be wary in any patient with infero-lateral ischaemia.
✤ Posterior MI is suggested by the following changes in V1-3:
✤ Horizontal ST depression
✤ Tall, broad R waves (>30ms)
✤ Upright T waves
✤ Dominant R wave (R/S ratio > 1) in V2
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Posterior MI✤ Posterior Leads:
✤ V7 – Left posterior axillary line, in the same horizontal plane as V6.
✤ V8 – Tip of the left scapula, in the same horizontal plane as V6.
✤ V9 – Left paraspinal region, in the same horizontal plane as V6.
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Posterior MI
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Posterior MI
✤ The degree of ST elevation seen in V7-9 is typically modest – note that only 0.5 mm of ST elevation is required to make the diagnosis of posterior MI!
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Posterior MI
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Posterior MI
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Brugada Syndrome
✤ 25 year old Asian male has had a collapse. Now feels fine and wants to go home...
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Brugada Syndrome
✤ Brugada syndrome is an ECG abnormality with a high incidence of sudden cardiac death in structurally normal hearts...
✤ Sodium channel mutation (at least 60 different types described so far)
✤ Diagnosis depends upon ECG criteria (which may be transient and clinical criteria (VF, VT, syncope, FHx sudden cardiac death <45)
✤ Definitive treatment = ICD
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Brugada Syndrome✤ May be unmasked / augmented by the following:
✤ Fever
✤ Ischaemia
✤ Multiple Drugs: Sodium channel blockers (eg Flecainide, Propafenone), Calcium channel blockers, Alpha agonists, Beta Blockers, Nitrates, Cholinergic stimulation, Cocaine, Alcohol
✤ Hypokalaemia
✤ Hypothermia
✤ Post DC cardioversion
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Brugada Syndrome - Type 1
Type 1: Coved ST segment elevation >2mm in >1 of V1-V3 followed by a negative T wave (don’t confuse with RBBB which
should have ST depression)
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Brugada Syndrome - Type 2
Type 2 has >2mm of saddleback shaped ST elevation.
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Brugada Syndrome - Type 3
Brugada type 3 can have either type 1 or type 2 morphology, but with <2mm of ST segment elevation.
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Brugada Syndrome
✤ Do they need admitting?
✤ Type 1 ECG and symptomatic = YES!
✤ If undiagnosed - 10% mortality per year...
✤ Asymptomatic patients with a type 1 ECG pattern and all type 2 + 3 ECG patterns can probably go home and have outpatient electrophysiology...
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Brugada Syndrome
✤ ...however, EPS is far from a gold standard, with a negative predictive value of less than 50% and some studies suggest that we might be getting a little over-excited about this relatively recently described ECG finding (1992).
✤ One study followed 98 asymptomatic japanese patients with a type 1 ECG found incidentally for 7.8 years and found them to have no greater mortality than the rest of a 14000 strong cohort. This highlights the importance of the clinical criteria required for diagnosis listed above.
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Trifasicular block
✤ Disease in all 3 conduction fasicles (RBB, LAF, LPF)
✤ May be complete or incomplete:
✤ Incomplete (or Impending) – RBBB, LAD, 1st degree HB
✤ Complete – 3rd degree HB and bifasicular block (usually RBBB and LAD)
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Trifasicular block (incomplete)
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Trifasicular block✤ Incomplete trifascicular block may progress to
complete heart block.
✤ Patients who present with a syncopal episode and have an ECG showing incomplete trifascicular block should be admitted for a cardiology review as they may be having episodes of complete heart block. Therefore, some of these patients will require a pacemaker.
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VT or SVT with aberrant conduction???
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VT or SVT with aberrant conduction???
✤ 3 possibilities:
✤ VT
✤ SVT with aberrant conduction due to bundle branch block
✤ SVT with aberrant conduction due to the Wolff-Parkinson-White syndrome
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VT or SVT with aberrant conduction???
✤ While it is not always possible to differentiate VT from SVT with aberrant conduction it is important to try. SVT is amenable to AV nodal blockers. But someone in VT can suffer haemodynamic collapse if AV blockers given...
✤ Unfortunately, the electrocardiographic differentiation of VT from SVT with aberrancy is not always possible. However, there are several electrocardiographic features that increase the likelihood of VT:
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More likely to be VT...
✤ Absence of typical RBBB or LBBB morphology
✤ Extreme axis deviation (“northwest axis”)
✤ Very broad complexes (>160ms)
✤ AV dissociation (P and QRS complexes at different rates)
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More likely to be VT...✤ Capture beats — occur when the sinoatrial node transiently
‘captures’ the ventricles, in the midst of AV dissociation, to produce a QRS complex of normal duration.
✤ Fusion beats — occur when a sinus and ventricular beat coincides to produce a hybrid complex.
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More likely to be VT...
✤ Brugada’s sign – The distance from the onset of the QRS complex to the nadir of the S-wave is > 100ms
✤ Josephson’s sign – Notching near the nadir of the S-wave
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More likely to be VT...
✤ Positive or negative concordance throughout the chest leads, i.e. leads V1-6 show entirely positive (R) or entirely negative (QS) complexes, with no RS complexes seen.
✤ RSR’ complexes with a taller left rabbit ear. This is the most specific finding in favour of VT. This is in contrast to RBBB, where the right rabbit ear is taller.
VT
RBBB
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The likelihood of VT is also increased if:✤ Age > 35 (positive predictive value of 85%)
✤ Structural heart disease
✤ Ischaemic heart disease
✤ Previous MI
✤ Congestive heart failure
✤ Cardiomyopathy
✤ Family history of sudden cardiac death (suggesting conditions such as HOCM, congenital long QT syndrome, Brugada syndrome or arrhythmogenic right ventricular dysplasia that are associated with episodes of VT)
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The likelihood of SVT with aberrancy is increased if:✤ Previous ECGs show a bundle branch block pattern with
identical morphology to the broad complex tachycardia.
✤ Previous ECGs show evidence of WPW (short PR < 120ms, broad QRS, delta wave).
✤ The patient has a history of paroxysmal tachycardias that have been successfully terminated with adenosine or vagal manoeuvres.
✤ HOWEVER - IF IN DOUBT TREAT AS VT
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Quiz Answers Q1
✤ 55 year old man presents with central crushing chest pain.
✤ Comment on the ECG and what is you treatment plan?
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Quiz Answers Q1
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Quiz Answers Q1
✤ NSR
✤ Widespread ST depression
✤ Elevation in aVR --> LMCA lesion!!
✤ D/W Papworth for ?PPCI, ACS Rx etc…
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Quiz Answers Q2
✤ 78 year old diabetic man. Previous MI. Presents with sudden onset SOB and an odd feeling in chest.
✤ Comment on the ECG and what is you treatment plan?
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Quiz Answers Q2
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Quiz Answers Q2
✤ Paced rhythm - Broad complexes
✤ Positive Scarbossa Criteria
✤ > 5mm ST elevation in III, aVF
✤ < 1mm ST depression V2, V3
✤ 1mm ST elevation aVL
✤ Needs PPCI
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Quiz Answers Q3
✤ 45 year old male. Brought in by wife after an episode of severe indigestion last night. Now symptoms free. Insists he’s fine and wants to go home. Thinks his wife is worrying unnecessarily.
✤ Obs fine. Bloods normal. Trop 12.
✤ Comment on the ECG and what is your management plan?
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Quiz Answers Q3
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Quiz Answers Q3
✤ Wellens’ type 1 - deep symmetrical TWI anteriorly.
✤ Likely has a severe LAD stenosis and should be investigated urgently.
✤ Refer medics for urgent angiography.
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Quiz Answers Q4
✤ 78 year old lady who presents with ischaemic chest pain.
✤ Comment on the ECG.
✤ How can you confirm your diagnosis and what is your management plan?
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Quiz Answers Q4
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Quiz Answers Q4
✤ Likely posterior MI (borderline inferior MI also)
✤ Anterior ST depression with a dominant R wave.
✤ Confirm with posterior leads
✤ Treat as per AMI - PPCI
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Quiz Answers Q5
✤ 20 year old student. Brought in after collapse.
✤ Went to feel lightheaded and then blacked out for a few seconds.
✤ Not happened before. Now feels fine and wants to go home.
✤ Comment on his ECG and what would you tell him?
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Quiz Answers Q5
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Quiz Answers Q5
✤ Brugada syndrome type 1
✤ Risk of sudden death. Need admission for an ICD...
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Quiz Answers Q6
✤ VT OR SVT?
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Quiz Answers Q6
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Quiz Answers Q6
✤ Probably SVT with aberrant conduction.
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