STEMI inferolateral

Introduction

The inferior wall can be supplied by the right coronary artery (RCA) via posterior descending artery (PDA) (in 80%) or PDA originating from the circumflex artery (RCA)  (20%). 

The lateral wall of the left ventricle is supplied by branches of the left anterior descending (LAD) and left circumflex (LCx) arteries.  

Etiology 

The majority of inferolateral MIs are caused by RCA occlusion. 

ECG features

  • ST elevation in the leads II, III, aVF, V5-6 (+-I, aVL) are indicating an extensive infarction of inferior and lateral walls.
  • Reciprocal changes in anterior leads

 Management

  • coronary angiography/PCI
  • UFH
  • ASA
  • P2Y12 inhibitors
  • nitrates
  • analgesia
  • 02  

ECG 1 STEMI inferolateral (atrial fibrillation related embolic occlusion of circumflex and second marginal artery bifurcation) - ST elevations in inferolateral leads, ST depressions in V1-V3 

ECG 2 STEMI inferolateral - ST elevations in II, III, aVF, V5-V6, ST depressions in V1-V4

References

  1. Dr. Smith's ECG Blog: Inferolateral STEMI: is there right ventricular MI also?. Dr. Smith's ECG Blog [online]. http://hqmeded-ecg.blogspot.com/2019/01/inferolateral-stemi-is-there-right.html
  2. Berger PB, Ryan TJ. Inferior myocardial infarction: High-risk subgroups. Circulation. 1990; 81(2): 401-11.
  3. https://litfl.com/inferior-stemi-ecg-library/
  4. Ibanez B, James S, Agewall S, Antunes MJ, Bucciarelli-Ducci C, Bueno H, Caforio ALP, Crea F, Goudevenos JA, Halvorsen S, Hindricks G, Kastrati A, Lenzen MJ, Prescott E, Roffi M, Valgimigli M, Varenhorst C, Vranckx P, Widimský P. 2017 ESC Guidelines for the management of acute myocardial infarction in patients presenting with ST-segment elevation: The Task Force for the management of acute myocardial infarction in patients presenting with ST-segment elevation of the European Society of Cardiology (ESC). Eur Heart J 2018;39:119–177.