What effects do LBBB, RBBB and LVH with repolarization abnormalities have on exercise stress testing interpretation?
🔴 LBBB → ST changes are unreliable due to abnormal repolarization. False-positive ST depressions may appear in V5-V6, I, aVL. Instead, use nuclear stress imaging or stress echo for accurate assessment.
🔵 RBBB → Less impact than LBBB, but ST-T changes in V1-V3 are not ischemic. Focus on inferolateral leads (V5-V6, II, III, aVF, I, aVL) for valid ischemia detection.
🟢 LVH with repolarization abnormalities → ST depressions & T-wave inversions (strain pattern) are common, especially in lateral leads (I, aVL, V5-V6). These changes often lead to false positives, making imaging crucial for confirmation.