Left ventricular hypertrophy – Part II

I know I promised to go over the voltage criteria for left ventricular hypertrophy (LVH) but I lied!

If you’re really interested you can check out the Wikipedia article HERE, the ECG Learning Center HERE, or Tom Evans’ crib sheet HERE.

Personally? I think it’s a distraction. As far as STEMI recognition goes, it misses the point entirely!

The ECG will either show a so-called “strain pattern” (or repolarization abnormality) or it will not! If it does, there’s a chance it will mimic an acute anterior STEMI.

Just because the voltage criteria for LVH is satisfied on a particular ECG does not mean that a secondary ST-T wave abnormality will be present! Even if it is, it will not necessarily mimic acute anterior STEMI.

What I’m trying to say (again) is this:

It’s far more important to recognize a strain pattern than it is to calculate the voltage criteria for left ventricular hypertrophy on a 12-lead ECG!

Having said that, I do know most of the voltage criteria for left ventricular hypertrophy, so I’m not trying to discourage you from learning. I just want to put it in context!

Let’s look at a couple of examples courtesy of my friend Tom Bernesser who is a paramedic in North Carolina. Both of these ECGs are actual “false positives” from North Carolina’s RACE program.

That means they presented with signs and symptoms consistent with ACS, acute STEMI was identified on the prehospital 12-lead ECG (including the computerized interpretive statement), the paramedic and the ED physician agreed the patient satisfied the reperfusion criteria, the patient was fast-tracked to the cardiac cath lab, and no culprit artery was found.

Example #1.

This is an atypical “strain pattern” with many typical features.

I suspect the possibility that leads V1 and V2 might have been accidentally transposed but that doesn’t really matter. For the purposes of STEMI recognition, the typical features outweigh the atypical features.

In the first place, you should immediately notice the “widened QRS-T angle” that is the hallmark of a secondary repolarization abnormality. You will notice the same finding for LBBB and paced rhythm!

Importantly, the degree of the secondary ST-T abnormality is, generally speaking (there are some caveats), proportional to the size (or amplitude) of the QRS complex in the opposite direction!

If you take nothing else away from this post, please learn this “trick”.

It’s really no different from the concept I demonstrated in the post called Wolff-Parkinson-White (WPW) – STEMI Mimic.

Herein lies a problem with prehospital 12-lead ECGs!

With left ventricular hypertrophy (LVH) the QRS complexes are often “cut off” at the top or bottom or they run together with other QRS complexes which can create the illusion that the QRS complexes are smaller, so you have to train your eye!

Take a look at this ECG and find the most severe ST-T wave abnormality.

That’s easy! Lead I clearly shows the most pronounced ST-T wave abnormality. The ST-segment is depressed, downwardly concave, and shows a deep inverted T-wave.

Does the amplitude of the R-wave in the opposite direction explain it? No way! It’s even smaller than the QRS complex in lead II, and the ST-T wave abnormality in lead II isn’t nearly as severe!

What is the second-worse ST-T wave abnormality? Lead V3! Does the depth of the S-wave in the opposite direction explain it? Not really.

But wait! Are we certain we’re getting an accurate “read” on the amplitude of the R-wave in lead I and the depth of the S-wave in lead V3?

I’m not so sure!

I suspect the possibility that the computer is “cropping” the QRS complexes to fit them on the ECG paper. See the little horizontal line that marks the “top” and “bottom” of these QRS complexes?

I’ve seen it many times before!

So ask yourself this question:

Generally speaking, does there seem to be a relationship between the QRS-complex and the degree of ST-elevation or depression in the opposite direction?

If the answer is “Yes!” then don’t call the STEMI Alert. Instead, perform serial ECGs and look for changing ST-segments and T-waves! ST-segments and T-waves shouldn’t “evolve” or change over time if it’s a simple secondary ST-T wave abnormality!

Example #2

Using the new “trick” you have learned, what do you think of this ECG?

More discussion to follow.

See also:

Left ventricular hypertrophy – Part I

Left Ventricular Hypertrophy May Result In Profound ST Elevation – Dr. Smith’s ECG Blog


  • Christopher says:

    The first 12L is less obvious than the second 12L which has "a lot of ink". Reviewing 12L #1, I would probably have called the STEMI! Although, the ST segment shape doesn't necessarily fit with what I'd be expecting ("leaning back" is what I see).

  • Tom B says:

    Christopher -What does "leaning back" mean? I'm not familiar with that terminology! In some ways, the first ECG is more "classic" for LVH than the second. However, the well defined J-points in leads V1 and V2 are unusual, along with the strange progression of the S-wave between V1 and V3.Otherwise, it's a homerun LVH with "strain pattern" ECG! Incidentally, the first ECG meets the limb lead criteria for LVH, which is why it's a mistake to limit yourself to the "S-wave in V1 (or V2 according to some sources) plus the R-wave in V5 or V6 = or > 35 mm" rule! The second ECG shows a downwardly deflected "strain pattern" in the inferior leads, which is unusual! We usually see that in the lateral leads, so again, there are no guarantees, but it seems to me the thing to look for is the ST-segment and T-wave discordance! It's a good indicator that you're probably dealing with a STEMI mimic! Tom

  • Christopher says:

    "Leaning back," that is if I were to sit on the ST segment, would it be comfortable to lean back on 🙂 It was described this way by one of our instructors and it appears to have stuck with me.I'm less familiar with the limb lead LVH voltage criteria, but I definitely can see where the R waves have a large amplitude.With that much ink on the page in the 2nd ECG, I was immediately drawn to LVH and was on the prowl for T-wave concordance. The first one, since the monitor chopped off the waves, didn't perk up the automagic search for "strain patterns". I hope I'll get better the more of these I'm exposed to 😉

  • Christopher,R waves in…Lead I, 12mm or greateraVL 11mm or greateraVF 20mm or greaterTom, good call on the cut off waves in the first ECG. Is it a Zoll thing or an adjustable option? Do you know?

  • Tom B says:

    Christopher – Okay! Now I get it.Yes, the T-wave inversion should be asymmetrical with a strain pattern in the setting of LVH! Particularly pronounced in the first ECG with the bradycardia (and associated longer QT-interval).Tom

  • Tom B says:

    Adam – I've seen it on all three (Physio-Control, ZOLL, and Philips). I don't think it's adjustable. I think it's just a consequence of using small rolls of graph paper! Tom

  • VinceD says:

    Wow, good point on the cropping of the QRS segments. I've done almost all of my ECG's on in-hospital setups with big paper, and now that I'm doing pre-hospital work as well, I probably would never have considered that the monitor might be cutting off the QRS if I saw ST changes as apparent as the first ECG.

  • Wes says:

    Tom, what is the best method to identify a stemi in the presence of lvh. If a strain pattern is recognized with typical asymmetrical inverted t waves in the high lateral leads and voltage criteria in the precordials. Do you recommend using Sgarbossa’s Criteria if this patient is presenting with acs symptoms?

  • Floyd says:

    This comment is a little late. What about your typical lvh strain pattern morphology of the st segments, that are semi-proportional to the q-r-s segments but without the amplitude "criteria" for LVH. Thank you, Floyd.

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