What findings indicate posterior wall MI on ECG?

Prepare for the Cleveland Clinic EKG Test with flashcards and multiple choice questions. Gain insights with hints and explanations. Ace your exam today!

Multiple Choice

What findings indicate posterior wall MI on ECG?

Posterior wall myocardial infarction is best identified by reciprocal changes seen in the standard chest leads, because the posterior surface isn’t directly seen with these leads. When the posterior wall is infarcted, the anterior leads (V1–V3) typically show ST depression and tall R waves—the mirror image of what would be seen as ST elevation and Q waves if viewed directly from the posterior perspective. If posterior leads (V7–V9) show ST elevation, that confirms the posterior infarct. So the pattern of ST depression and tall R waves in V1–V2 with concurrent reciprocal ST elevations in the posterior leads V7–V9 is the classic sign of a posterior wall MI. The other patterns point to different localizations or non-specific findings: ST elevations in V1–V3 suggest an anterior wall MI, tall R waves in V5–V6 are not the posterior pattern, and ST depressions in II, III, aVF point to an inferior MI with different reciprocal changes.

Posterior wall myocardial infarction is best identified by reciprocal changes seen in the standard chest leads, because the posterior surface isn’t directly seen with these leads. When the posterior wall is infarcted, the anterior leads (V1–V3) typically show ST depression and tall R waves—the mirror image of what would be seen as ST elevation and Q waves if viewed directly from the posterior perspective. If posterior leads (V7–V9) show ST elevation, that confirms the posterior infarct. So the pattern of ST depression and tall R waves in V1–V2 with concurrent reciprocal ST elevations in the posterior leads V7–V9 is the classic sign of a posterior wall MI. The other patterns point to different localizations or non-specific findings: ST elevations in V1–V3 suggest an anterior wall MI, tall R waves in V5–V6 are not the posterior pattern, and ST depressions in II, III, aVF point to an inferior MI with different reciprocal changes.

More practice questions