ABSTRACT
Purpose: The T wave in precordial lead V1 is normally inverted in normal adults. The significance of an upright T wave in precordial lead V1 as to the presence of coronary artery disease is controversial and not well studied in the literature. Our purpose is to show the relation between an upright T wave in V1 and the presence of coronary artery disease and specifically that of the circumflex
Material and methods: We studied, retrospectively, 624 consecutive patients referred for cardiac catheterization with normal electrocardiograms excluding patients with acute coronary syndromes, bundle branch blocks, left ventricular hypertrophy, intraventricular conduction delays, pacemakers, ST-T changes, significant valvular heart disease, cardiomyopathies and metabolic disorders. Significant coronary artery stenosis was considered when the stenosis was > 70%; normal or nonsignificant coronary artery stenosis was considered when the coronary stenosis was < 70% [all patients had < 50% coronary stenosis]. The ECG's and coronary arteriographies were reviewed. The 2x2 chi-square was used for statistical analysis
Results: Out of the 624 patients, 380 [60.89%] had normal coronary arteries out of which only 17 [4.47%] had an upright T wave in V1, 244 [39.11%] had significant coronary artery disease out of which 137 [56.14%] had positive T wave in V1, significantly more than the normal population with a p value < 0.0001. A total of 142 patients had significant circumflex stenosis out of whom 128 [90.1%] had a positive T wave in V1; a total of 482 patients had no significant circumflex stenosis, out of whom only 26 [5.39%] had a positive T wave in V1, the difference was highly significant with a p value < 0.00001 as to the presence of a T upright in V1 in patients with significant circumflex stenosis. This significance was maintained when excluding the patients with diabetis mellitus
Conclusion: An upright T wave in V1 is significantly related to the presence of significant coronary artery stenosis and specifically the circumflex coronary artery