the long way round…
the case.
a 52 year old male presents to your Emergency Department with more than 24 hours of typical sounding, retrosternal chest pain.
He has a prior history of ischaemic heart disease & an LAD stent placed 3 years earlier.
On examination:
Pale & clammy.
P 136/min, BP 104/60 mmHg, SaO2 92% (RA).
RR 30 with slight bilateral crackles.
This is his ECG…
[DDET Describe & interpret his ECG…]
- Rate:
- 138 bpm.
- Rhythm.
- Sinus.
- Axis.
- Normal [+40*].
- Intervals.
- PR ~ 160msec.
- QRS ~ 80msec.
- QTc ~ 380msec.
- Segments.
- Widespread ST elevation;
- “Tombstone” STE V1-4 [max ~5mm] w/ associated Q-waves.
- Concave-up STE V5-6 + lead I
- Concave-up STE [1-2mm] in inferior leads [II, III + aVF].
- ST-depression in aVR ~1.5mm.
- PR segments.
- Depressed in III + aVF
- ?subtle elevation in aVR
- Widespread ST elevation;
Interpretation.
Widespread ST-segment elevation consistent with acute anterior “tombstone” ST-elevation myocardial infarction meeting reperfusion criteria.
- Prior Hx of LAD stent + presence of anterior Q-waves ?stent thrombosis
- Inferior ST-segment elevation.
- ?wrap around LAD
- ???associated pericarditis.
The presence of tachycardia, basal crackles and borderline hypotension is concerning for early cardiogenic shock.
This patient warrants early Cardiology involvement and prompt transfer for PCI.
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[DDET The angiogram…]
Left ventriculogram:
- Ejection fraction ~ 49%
- Regional wall motion abnormalities:
- Anterolateral akinesis
- Apical akinesis
- Inferior hypokinesis
Angiogram:
Left coronary…
100% mid-LAD occlusion → successfully stented [see below]
Right coronary…
Despite the inferior changes, the RCA was pristine.
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[DDET Post-balloon…]
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[DDET The diagnosis…]
Wrap around LAD.
ECG.
- Simultaneous ST-segment elevation in the precordial and inferior leads.
In the presence of anterior STEMI, the amount of ST depression in the inferior leads is typically predictive of a more proximal LAD lesion. Even in the presence of a wrap-around LAD (ie. with inferior wall transmural ischaemia), almost all LAD occlusion proximal to D1 is show inferior ST depression.
A more distally occluded LAD is thought to be a prerequisite for isoelectric inferior ST-segments.
Additional ECG findings suggestive of a wrap-around LAD include ST-depression in lead III (with a positive T-wave) associated with ST-elevation in aVL.
Anatomically.
- Occurs due to an occlusion of a variant “type III” LAD.
- This wraps around the cardiac apex, supplying both the anterior and [partial] inferior walls of the left ventricle.
In our patients’ case;
For more examples of wrap around LAD lesions check out the following from Dr Smith’s ECG Blog;
- 24 yo woman with chest pain: Is this STEMI? Pericarditis?
- Pericarditis, or Anterior STEMI? The QRS proves it.Hyperacute T-waves, with a Twist
- Hyperacute T-waves, with a Twist.
Interestingly, the combination of anterior and inferior ST-segment elevation appears to be associated with limited AMI size and better preserved LV function (when compared to anterior STEMIs with either isoelectric or depressed inferior ST segments).
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[DDET References.]
- Sadanandan, S., et al. (2003). Clinical and angiographic characteristics of patients with combined anterior and inferior ST-segment elevation on the initial electrocardiogram during acute myocardial infarction. American Heart Journal, 146(4), 653–661.
- Engelen, D. J., et al. (1999). Value of the electrocardiogram in localizing the occlusion site in the left anterior descending coronary artery in acute anterior myocardial infarction. Journal of the American College of Cardiology, 34(2), 389–395.
- Porter A, Sclarovsky S, Ben-Gal T, et al. Value of T-wave direction with lead III ST-segment depression in acute anterior myocardial infarction: electrocardiographic prediction of a wrapped left anterior descending artery. Clin Cardiol 1998;21:562–6.
- Gibson, CM., et al. (1996). TIMI frame count: a quantitative method of assessing coronary artery flow. Circulation. 1996 Mar 1;93(5):879-88.
- Anterior myocardial infarction – Life in the Fast Lane.
- Dr Smith’s ECG Blog
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