From the Guidelines
T wave inversions in inferior leads (II, III, aVF) should prompt immediate evaluation for acute coronary syndrome (ACS) and consideration of further cardiac workup, as they may indicate myocardial ischemia or infarction, particularly if the inversions are new or dynamic. These findings can represent several cardiac conditions that require clinical correlation, including myocardial ischemia or infarction affecting the inferior wall of the heart, right ventricular strain, pulmonary embolism, or as a normal variant in some individuals 1. When encountering inferior T wave inversions, it is essential to compare with previous ECGs if available to determine if this is a new finding. Additional workup should include:
- Cardiac biomarkers (troponin) to assess for myocardial damage
- Assessment of other ECG leads for reciprocal changes, which can support the diagnosis of ACS
- Clinical evaluation for symptoms like chest pain or shortness of breath, which can guide the urgency of the workup If acute coronary syndrome is suspected, immediate cardiology consultation is warranted, along with:
- Appropriate antiplatelet therapy, such as aspirin 325mg loading dose followed by 81mg daily
- Consideration of anticoagulation to prevent further thrombus formation
- Possible cardiac catheterization to evaluate the coronary arteries and potentially intervene with angioplasty or stenting. T wave inversions occur due to alterations in ventricular repolarization, which can result from ischemia, electrolyte abnormalities, or structural heart changes affecting the inferior myocardium, as noted in the 2014 AHA/ACC guideline for the management of patients with non-ST-elevation acute coronary syndromes 1.
From the Research
T Wave Inversions in Inferior Leads
- T wave inversions in inferior leads can be an early warning sign of impending myocardial infarction, particularly when associated with critical stenosis of the right coronary artery (RCA) or left circumflex artery (LCx) 2
- A study found that T wave inversions in the inferior leads, along with a tall T wave in V2-V3, were seen prior to the development of an inferior-posterior ST-elevation myocardial infarction (STEMI) 2
- Another study suggested that the sum of T wave inversion in inferior leads can be used to differentiate between acute coronary syndrome (ACS) and acute pulmonary embolism (PE), with a higher sum indicating ACS 3
- However, a study found that simultaneous T wave inversions in anterior and inferior leads were associated with pulmonary embolism (PE) but were seen in only 4-11% of cases 4
- T wave inversions in the inferior lead group were found to be a benign phenomenon, not associated with an increased risk of coronary heart disease (CHD) or mortality 5
- A lone T wave inversion in aVL can precede an inferior myocardial infarction, highlighting the importance of careful inspection of ECG findings 6