Old Myocardial Infarction Ecg Fixed Jun 2026

Hypertrophic Cardiomyopathy (HCM): Can produce deep Q waves due to a thickened septum rather than scar tissue. Clinical Importance

(adults):

“Sinus rhythm, rate 72. Pathologic Q waves in leads II, III, and aVF (duration 44–56 ms) consistent with old inferior myocardial infarction . No acute ST-segment elevations. Fragmented QRS noted in III and aVF. Compared to prior ECG from [date], findings are unchanged.” old myocardial infarction ecg

: Unlike an acute MI where you see ST-segment elevation , an old MI usually shows the ST segment returning to the baseline (isoelectric). Hypertrophic Cardiomyopathy (HCM): Can produce deep Q waves

In a normal heart, the R wave size increases progressively from lead V1 to V5 (a concept known as R-wave progression). In an old anterior infarction, this progression is disrupted. No acute ST-segment elevations

| Infarct location | Leads with pathologic Q waves | Coronary artery | Typical Q-wave morphology | |---|---|---|---| | | V2–V4 (may extend to V1–V5) | LAD | Loss of R wave progression; QR or QS in V2–V4 | | Inferior | II, III, aVF | RCA (80%) or LCx | Q ≥40 ms, often >1/3 of R in III, aVF | | Lateral | I, aVL, V5–V6 | LCx or diagonal | Narrow but deep Q; often subtle | | Posterior (old) | Tall R wave in V1–V2 (mirror of posterior Q) | RCA or LCx | R/S ratio >1 in V1-V2 with upright T wave (mirror test) | | Septal | V1–V2 | Septal perforators (LAD) | QS or QR; loss of small septal R |