ECG Flashcards
Approach
Rate
Rhythm
Axis
Ischaemia
Intervals
Others
R R intervals
300 / large box
P wave = SR
Axis = I and aVF
Territories:
Q S
V1 V2 septal
V3 4 anterior
V5 6 lateral
aVL I lateral
II III aVF
Interval
PR 1 box
QRS < 120ms
QT 440 460
J point
STE
S V2
R V5
LVH
Concentric hypertrophy
Rate: 80-85
Rhythm: SR
Axis: Normal
Ischaemia:
II III aVF - STEMI
Q wave: 6-8 hrs to develop = transmural infarction
Inferolateral STE - reperfusion - infarct
Q wave preceding STE - subacute infact
Reciprocal changes in anterior (V1 V2) lateral (avL) lead
Bottom strip
Mobitz I PR progressively increading
RCA infarct - supplies purkinje
- STE III > II + STD aVL - favours RCA infarct
- SII > III - favour Circumflex
Rate: 75
Rhythm: SR
Axis: LAD
Ischaemia: STE V2-V4 V5-V6
TWI III V1
Tombstone STE across praecordium
Q wave
V1 - widening QRS - efficiency of depolarisation
V1 Positive deflection - RBBB, posterior infarct, RVH/strain, WPW
Rate: 100, SR, normal
STE
Saddle shape morphology
PR
High takeoff V2-V6
Pleuritic CP
PR depression - pericardial
PERICARDIAL effusion
Rate: irregular >100 (120)
Rhythm: irregular, relationship P to QRS
V1 - P but does not mean SR
Irregular irregular
HTN –> LVH –> LVEDP inc –> atrial strain –> remodel –> AF
Degenerative
Nothing to ablate
3 P waves for every QRS
Fixed relationship
Macro Reentract Circuit
Ablatable / Cardiovert
Hard to control rate
AF rules
- Find the cause
- infection/TFT/ischaemia - Fix the cause
- Control rate
- anticoagulate
CHADVASc 2 = 2% / annum
No bridging required
V1 RSR TWI
V2
SR
Normal axis
Widened QRS in V2
RBBB
RBBB + LAD
LAFB
RBBB + RAD
LPFB
Bifascicular block
RV strain
1. Dom V wave R1
2. TWI V1-4, II,III,aVF
3. RAD
PE
PHTN
Memorizing ECG criteria for right ventricular (RV) strain, pulmonary embolism (PE), and pulmonary hypertension (PH) can be streamlined using systematic mnemonics and pattern recognition. Below is a structured approach based on high-yield findings from international guidelines and cardiology literature.
- Right Ventricular (RV) Strain
Key ECG Features ([1][11][12]):
- ST depression/T-wave inversions in right precordial leads (V1–V4) and inferior leads (II, III, aVF).
- Right axis deviation (> +110°).
- Dominant R wave in V1 (R/S ratio > 1 or R > 7 mm).
- Incomplete/complete RBBB (often transient in acute PE).
Mnemonic: “STRAIN”
- ST/T changes (V1–V4, II/III/aVF)
- Transient RBBB
- Right axis deviation
- Anterior T inversions (V1–V4)
- Inferior T inversions (II/III/aVF)
- Negative T waves (primary repolarization abnormalities)
- Pulmonary Embolism (PE)
Key ECG Features ([3][4][14]):
- Sinus tachycardia (most common finding).
- S1Q3T3 pattern: Deep S in I, Q in III, inverted T in III (specific but insensitive).
- Anterior T-wave inversions (V1–V4) ± inferior T inversions.
- Transient RBBB or right axis deviation.
Mnemonic: “S1Q3T3 + TIPS”
- S1Q3T3
- Tachycardia
- Inverted T waves (anterior/inferior)
- Pulmonary embolism
- Strain (RV)
- Pulmonary Hypertension (PH)
Key ECG Features ([5][6][7][10]):
- P pulmonale: Tall P waves (> 2.5 mm in II/III/aVF).
- Right axis deviation (> +110°).
- Dominant R in V1 (R/S > 1) ± deep S in V5–V6 (R/S 1.05 mV.
Mnemonic: “PHASES”
- P pulmonale
- Hypertrophy (RVH)
- Axis deviation (right)
- S waves (deep in V5–V6)
- Elevated RV pressures (ST/T changes in V1–V4)
- Strain pattern
Comparison Table
| Feature | RV Strain | PE | PH |
|————————|——————-|——————-|——————-|
| T-wave inversions | V1–V4, II/III/aVF | V1–V4, ± II/III/aVF | V1–V4, II/III/aVF |
| Axis | Right | Right/neutral | Right |
| RBBB | Common (acute) | Transient | Rare |
| Pulmonale | No | No | Yes (P > 2.5 mm) |
| Dominant R in V1 | ± | ± | Yes |
Clinical Pearls
1. Overlap: PE often causes acute RV strain, while PH reflects chronic RV pressure overload[1][11].
2. Specificity:
- S1Q3T3 is specific for PE but seen in 0.6 predicts severe PH[10].
By anchoring these patterns to clinical scenarios (e.g., sudden dyspnea → PE vs. progressive fatigue → PH), retention improves. Pairing ECG findings with bedside ultrasound (RV dilation on echo) or biomarkers (elevated troponin/BNP) enhances diagnostic accuracy[14][10].
Citations:
[1] https://en.wikipedia.org/wiki/Right_heart_strain
[2] https://pmc.ncbi.nlm.nih.gov/articles/PMC7307602/
[3] https://ecgwaves.com/topic/pulmonary-embolism-causes-risk-factors-diagnosis-wells-score-treatment/
[4] https://pmc.ncbi.nlm.nih.gov/articles/PMC4613926/
[5] https://pubmed.ncbi.nlm.nih.gov/17651847/
[6] https://pubmed.ncbi.nlm.nih.gov/36913785/
[7] https://www.wikidoc.org/index.php/Pulmonary_hypertension_electrocardiogram
[8] https://www.emdocs.net/ecg-pointers-7-cant-miss-ecg-patterns-of-high-risk-syncope-the-abcde-left-right-mnemonic/
[9] https://www.healio.com/cardiology/learn-the-heart/ecg-review/ecg-interpretation-tutorial/10-steps-course-to-learn-ecg-interpretation
[10] https://pmc.ncbi.nlm.nih.gov/articles/PMC11679519/
[11] https://litfl.com/right-ventricular-strain-ecg-library/
[12] https://litfl.com/right-ventricular-hypertrophy-rvh-ecg-library/
[13] https://www.youtube.com/watch?v=Hc97vk-Y6r8
[14] https://emergencymedicinecases.com/ecg-cases-26-pulmonary-embolism-and-acute-rv-strain/
[15] https://pmc.ncbi.nlm.nih.gov/articles/PMC6711008/
[16] https://www.ecgstampede.com/glossary/right-heart-strain/
[17] https://radiopaedia.org/articles/right-heart-strain
[18] https://www.maimonidesem.org/blog/right-heart-strain-on-ekg
[19] https://www.healio.com/cardiology/learn-the-heart/ecg-review/ecg-topic-reviews-and-criteria/pulmonary-embolism
[20] https://www.healthline.com/health/pulmonary-embolism-ecg
[21] https://pmc.ncbi.nlm.nih.gov/articles/PMC3267566/
[22] https://www.thepermanentejournal.org/doi/10.7812/tpp/11-112
[23] https://www.medscape.com/viewarticle/456942_4
[24] https://litfl.com/pulmonary-hypertension/
[25] https://www.mayoclinic.org/diseases-conditions/pulmonary-hypertension/diagnosis-treatment/drc-20350702
[26] https://www.archbronconeumol.org/en-the-electrocardiogram-in-pulmonary-hypertension-articulo-S1579212921000732
[27] https://litfl.com/ecg-changes-in-pulmonary-embolism/
[28] https://emergencymedicinecases.com/ecg-cases-poor-r-wave-progression-late-mnemonic/
[29] https://www.acc.org/Latest-in-Cardiology/ten-points-to-remember/2022/08/30/19/11/2022-ESC-Guidelines-for-Pulmonary-Hypertension-ESC-2022
[30] https://www.healio.com/cardiology/learn-the-heart/cardiology-review/cardiology-mnemonics
[31] https://www.youtube.com/watch?v=ktj5eo_932s
[32] https://www.ahajournals.org/doi/10.1161/circulationaha.114.006971
[33] https://geekymedics.com/pulmonary-embolism-pe-acute-management-abcde-approach/
[34] https://pmc.ncbi.nlm.nih.gov/articles/PMC8129798/
[35] https://www.healio.com/cardiology/learn-the-heart/ecg-review/ecg-topic-reviews-and-criteria/right-ventricular-hypertrophy-review
[36] https://pubmed.ncbi.nlm.nih.gov/9118684/
[37] https://onlinelibrary.wiley.com/doi/10.1111/acem.12769
[38] https://gpnotebook.com/en-AU/pages/cardiovascular-medicine/ecg-changes-in-pulmonary-embolus-pe
[39] https://pmc.ncbi.nlm.nih.gov/articles/PMC5306533/
[40] https://casereports.bmj.com/content/2013/bcr-2013-008697
[41] https://pmc.ncbi.nlm.nih.gov/articles/PMC2516288/
[42] https://litfl.com/ecg-in-chronic-obstructive-pulmonary-disease/
[43] https://publications.ersnet.org/content/erj/37/5/994
[44] https://publications.ersnet.org/content/erj/53/1/1801904
[45] https://oxfordmedicaleducation.com/ecgs/ecg-interpretation/
[46] https://pmc.ncbi.nlm.nih.gov/articles/PMC10363571/
Answer from Perplexity: pplx.ai/share
Brugada: electrical condition ~ SCD
Different morphology of STE
Downsloping pattern
SR
Broadened QRS
LAD
Broad complex tachycardia
Monomorphic VT
RV OT VT
Narrow complex tachy
Rate: 150
AVNRT
Treat with adenosine
SVT - include AF/A flutter
Look for retrograde P wave
CHB
Complete dissociation P and QRS
2ND degree AV block
WPW
slurred upstroke
VT
HoCM
J point
Diffuse deep TWI across V1-V6
