Coronary sinus catheterization is important in electrophysiological studies. However the mor-phologic feature of the coronary sinus and its significance in patients with supraventricular tachycardia (SVT) have not been determined. During diagnostic electrophysiological studies, coronary sinus catheterization was easier in patients with atrioventricular nodal reentry tachycardia (AVNRT) than in patients with atrioventricular reentry tachycardia (AVRT). Therefore, we studied coronary sinus morphology in patients with SVT and compared AVNRT and AVRT patients.

The size and shape of the coronary sinus were measured in 13 patients who underwent retrograde coronary sinus venogram during electrophysiologic study between May and June 1996. The diagnosis was 7 cases of AVNRT, 2 of Wolff-Parkinson-White syndrome and 4 of concealed bypass tracts (mean age, 40 years : male vs female, 1 : 1.2).

The mean coronary sinus ostial diameter was 10.4±2.0 mm:for AVNRT, it was 11.4±2.2 mm, and for AVRT it was 9.3±1.0 mm in left anterior oblique projection (p=0.031). The mean coronary sinus-to-spine angle was 82.6±17.4degrees : AVNRT 95.4±24.4degrees and AVRT 67.7±15.2degrees in anterior posterior projection (p=0.035).

The coronary sinus ostial diameter of AVNRT patients was significantly larger than that of AVRT patients. This finding may have important implications for arrythmia pathogenesis in such patients.