Discussion. This tracing is from a 17-year-old boy with Duchenne muscular dystrophy who is wheelchair-bound. The tall R waves in V1 and deep, narrow Q waves in leads 1, aVL, and V4-6 are typical ...

The P waves are negative in leads V1-V2, consistent with a left atrial abnormality or left atrial hypertrophy. ... Lateral wall myocardial infarction (with a deep Q wave in leads I and aVL) ...