Differential Diagnosis for RSR Pattern in Lead 1 and aVL with 'W' Pattern in V1

• Single Most Likely Diagnosis
  • Acute Coronary Syndrome (ACS) with Lateral and Anterior Involvement: The RSR' pattern in leads I and aVL suggests lateral wall involvement, while the 'W' pattern (also known as a "W" sign or a pseudo-S wave) in V1 can indicate anterior wall ischemia or infarction. This combination can be seen in ACS affecting both lateral and anterior territories.
• Other Likely Diagnoses
  • Lateral and Anterior Myocardial Infarction: Similar to ACS, but this diagnosis implies completed infarction rather than ongoing ischemia. The ECG findings support the involvement of both lateral and anterior walls.
  • Left Ventricular Hypertrophy (LVH) with Strain Pattern: LVH can cause an RSR' pattern in lateral leads due to increased voltage, and a 'W' pattern in V1 might be seen due to the strain pattern associated with LVH, although this is less common.
• Do Not Miss Diagnoses
  • Pulmonary Embolism (PE): Although less common, a large PE can cause right ventricular strain, leading to ECG changes that might mimic or overlap with the described pattern, especially if there's associated right ventricular ischemia or infarction.
  • Cardiac Sarcoidosis: This condition can cause various ECG abnormalities, including patterns that mimic myocardial infarction or ischemia, due to granulomatous infiltration of the myocardium.
• Rare Diagnoses
  • Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC): This condition primarily affects the right ventricle and can cause ECG abnormalities, including a 'W' sign in V1 due to epsilon waves, but it's less likely to cause an RSR' pattern in leads I and aVL.
  • Myocardial Bridging: This is a rare condition where a portion of a coronary artery dives into and is surrounded by myocardium. It can cause ischemia, especially during exercise, and might lead to ECG changes, but it's an uncommon cause of the described pattern.