Correlation between non-reversible thallium-201 myocardial perfusion defect and ECG criteria in the diagnosis of apical myocardial infarction

Background: ECG identification of apical myocardial infarction (MI) is controversial and lacks of accuracy. Our aim was to investigate the sensitivity of different proposed ECG criteria in the presence of apical perfusion defects assessed with SPECT analysis. Methods: One hundred twenty-four (98 M, 26 F) out of 1500 patients with suspected coronary artery disease, showed apical perfusion defect not reversible at rest and after reinjection at tomographic SPECT analysis during thallium-201 scintigraphy. Results: In the group of 29 patients presenting wide isolated apical perfusion defect (wAPD) Q waves in anterior segments with definition of antero-septal MI was prevalent (51.7%), while few patients (41.3%) presented the ECG criteria of apical MI as proposed in the literature. In 19 of the 25 patients with partial isolated apical perfusion defect (pAPD), the absence of Q wave was clearly prevalent. Fifty patients had a wAPD partially extended in surrounding regions, as anterior or septal, inferior or lateral myocardial segments, in these patients, the site of Q wave location was more variable, with prevalent Q wave in anterior leads, but with more incidence of Q waves in leads II III aVF, especially in patients with associated perfusion defect in inferior segments. Substantially, the same finding resulted in the 20 patients showing a pAPD extended in surrounding myocardial segments. Conclusion: In conclusion, the low diagnostic sensitivity of the ECG criteria of identification of apical MI is clearly demonstrated by our analysis carried out using SPECT perfusion scintigraphy, with ECG findings of anterior/anterior- septal myocardial necrosis in the patients with wAPD.