8/22/24 LVH - Beware OMI

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Written by Esteban Davila MD and Eric Tang MD

Learning Objectives

Recognize the common ECG characteristics of LVH
Understand the limitations of ECG diagnostic criteria for OMI in patients with LVH and utilize strategies to workup these patients
Differentiate between LVH and OMI

LVH ECG

Voltage Characteristics

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ECG finding #1: Precordial (V1-V6) QRS complexes are large and may touch & overlap.

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ECG finding #2: Left sided leads may have tall R waves

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ECG finding #3: Right sided and anterior leads may have deep S waves

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ECG finding #4: A combination of #2 and #3 increases the specificity for LVH.

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Exception: Generally, QRS duration in LVH is ≤ 120 ms, with the exception of RBBB. If LBBB or an interventricular conduction delay is present, LVH cannot be diagnosed.

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Should you memorize all the voltage criteria?

ECG Practice (7 ECGs)

What voltage findings are suggestive of LVH? Just focus on voltage.

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Source

Hold up…I’m an EM doctor. Do I care about diagnosing LVH in the ED?

In most cases…no. However, you do care about diagnosing MI in LVH. The presence of LVH on ECG makes the diagnosis of ischemia very difficult and this has tortured EM doctors since the dawn of our specialty. In fact, the Fourth Universal Definition of MI excludes the LVH from “classic” STEMI findings (Table 2 below). Knowing that the typical rules of ST segment elevation and depression may not apply to LVH is crucial.

Non-voltage Characteristics

The following LVH findings are classically known as “strain pattern” but now are often referred to as “repolarization abnormalities.” Not every ECG with LVH will have these abnormalities.

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ECG finding #1: Leads with tall R waves may have ST depressions (STD) and T wave inversions

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ECG finding #2: Leads with deep S waves may have ST Elevations (STE) and upright T waves. Some of these STE may be ≥ 2 mm in V2-V3 and ≥ 1mm in other leads.

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ECG finding #3: The lead with the tallest R wave may have the deepest STD and similarly the lead with the deepest S wave may have the tallest STE.

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ECG finding #4: STE and STD are generally concave and T waves are asymmetric

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ECG finding #5: You can’t diagnose strain pattern on an ECG without the presence of LVH.

LVH and OMI

Why is it difficult to distinguish LVH and OMI?

LVH is excluded when using STEMI criteria
LVH might cause enough STE to meet STEMI criteria
Common patterns normally specific for OMI can be normal in LVH

Have you noticed in LVH that the tallest R waves and deepest S waves are in leads that may be reciprocal to each other? This means there may be ST segments that are reciprocal to each other.

ECG findings that look like strain pattern may also represent OMI in LVH
Patients may clinically present exactly as a patient with ACS may present

Tips for identifying OMI in LVH

The following are ECG findings that may indicate OMI in LVH. The absence of these findings does not rule out OMI and the presence of these findings does not necessarily rule in OMI.

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Tip #1: Discordant STE is disproportionally tall compared to accompanying S wave.

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Tip #2: The largest discordant ST deviation does NOT accompany the tallest R or deepest S wave

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Tip #3: The ST segments are linear, horizontal, or convex.

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Tip #4: There are concordant STE.

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Tip #5: The T waves are symmetrical and may be disproportionally large relative to QRS complexes

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Other clues

Lastly, accept that there are no perfect ways to distinguish LVH from OMI with ECG, so use your adjuncts to aid your decision making (serial ECGs, troponin, echo)

ECG Practice (14 half ECGs)

Evaluate each set of limb or precordial limbs.

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Source 12 Lead ECG

After completion

Consider reviewing the following additional resources:

LVH with anterior ST Elevation. When is it anterior STEMI?
Jesse McLaren EM cases | ECG cases 13: LVH + occlusion MI
ECG Weekly: STAT ECG Diagnoses: How to identify acute coronary occlusion in LVH with strain
Chapters 11 and 14 of Tomas Garcia’s 12 Lead ECG: Art of Interpretation
Ed Burns Left Ventricular Hypertrophy (LVH)