Atrial coronary angiography, tachyarrhythmias and the Ta segment.

Electrocardiograms and angiograms were reviewed to determine if atrial Ta segment displacements and atrial flutter or fibrillation indicate atrial coronary disease. Atrial circulation was assessed by angiography in 28 patients with chest pain and normal coronary arteries, 29 patients with significant stenosis of at least one major coronary vessel, and 16 with coronary artery disease and atrial flutter or fibrillation. The prevalence of Ta segment displacement was 71% without coronary disease and 79% with coronary disease. There was no relationship between Ta displacement and segmental atrial coronary insufficiency. Among an additional 28 patients with acute transmural myocardial infarction, 79% had equivalent Ta segment displacement. Half of the patients with atrial flutter/fibrillation had significant mitral regurgitation, in contrast to 3% of coronary patients in sinus rhythm (p less than 0.001), but their atrial coronary circulation was not more severely compromised. Thus, Ta segment displacement did not identify atrial coronary disease and was not more frequent during acute myocardial infarction. Abnormal atrial perfusion did not explain Ta segment displacement or atrial flutter/fibrillation.