Hyperacute T-wave criteria using computer ECG analysis

Hyperacute T waves (HATWs) have been described as tall-amplitude, primary T-wave abnormalities sometimes seen in the early phases of transmural myocardial infarction. Despite numerous human and animal studies addressing the presence and significance of HATWs, there are no widely held, reliable ECG criteria for their accurate identification. Using a specially designed computer program on a Hewlett-Packard Realm ECG analysis system, we screened 13,393 adult ECGs to identify those having T-wave amplitudes greater than accepted standards (limb leads, greater than 0.5 mV; precordial leads, greater than 1.0 mV). Patients with other known causes of primary and secondary tall T waves were excluded from the study sample. Patients with tall-amplitude T-waves who then developed clinically verifiable myocardial infarction were labeled the HATW group. The HATW group (21) represented 4.1% of the tall T wave group (513) and 0.16% of the entire sample. The remaining patients, who did not meet HATW criteria, were called the early repolarization variant (ERV) group (51). Both groups underwent comparative computer morphology analysis. Nine parameters were statistically significant in discriminating HATWs from early repolarization variants. A combination of J-point position/T-wave amplitude of more than 25%, T-wave amplitude/QRS amplitude of more than 75%, J-point position of more than 0.30 mV, and age of more than 45 years predicted HATWs from a control group with a specificity of 98.0% and a sensitivity of 61.9% and with positive and negative predictive values of 92.9% and 86.2%, respectively. We conclude that HATWs have characterizable discriminating ECG morphology as determined by computer ECG analysis compared with a control group.