Detection of the sinus node artery using electron beam computed tomography of the heart.

Background: Stenosis or obstruction of the sinus node artery (SNA) of the heart can cause cardiac arrhythmia and even sudden death. The purpose of this study was to evaluate the detectability of the SNA using electron beam computed tomography (EBCT). Material and methods: Eighty patients (mean age: 61 ± 10 years, range: 31–80 years) were examined with ECG-triggered EBCT (exposure time: 100 ms, slice thickness: 1.5 mm), using two different detector systems (n = 40; 9.5 line pairs/cm [Lp/cm]; n = 40; 7 Lp/cm) after intravenous contrast agent administration. Twenty-four out of 80 (30%) patients had supraventricular arrhythmia. Result: The SNA was detected in 60/80 (75%) of all patients with an average length of 16 ± 7 mm (3–35.2 mm). One additional branch of the SNA was detectable in 17/80 patients (21%), two branches in 6/80 (8%). There was no significant difference between the two used detector systems (p < 0.01) or between patients with or without supraventricular arrhythmia (71 vs. 77%; p = ns). Conclusion: EBCT allows to detect small coronary arteries such as the SNA of the heart.