Imaging findings of Bachmann bundle and its arterial supply on dual-source CT coronary angiography

Abstract

Objective To investigate the morphologic features of Bachmann bundle (BB) and its vascular supply on dual-source CT coronary angiography(DSCTCA) in healthy volunteers and patients with coronary artery lesion (CAL). Methods Clinical histories, electrocardiograms (ECGs), and images of DSCTCA of 106 patients ( CAL group) and 100 healthy volunteers ( Control group) were reviewed. All 106 patients underwent conventional coronary angiography ( CCA ). The Gensini scoring system was used to assess the results of CCA. The patients were divided into three groups according to their Gensini scores. The length, width and superoinferior diameter, CT value, and vascular supply of BB were studied. Rank sum test for continuous variables and Chi-square test for categorical variables were used in statistical analysis.Results ( 1 ) BB visualization rate of control group was higher than CAL group [86.0% (86/100) vs 51.9%(55/106), x2 = 27.726, P ＜ 0.01]. The higher the Gensini score of CAL subgroup, the lower the visualization rate of its BB [80.0% ( 28/35 ), 55.6% ( 20/36 ), 20.0% ( 7/35 ), x2 = 25.530, P ＜ 0.01].(2)The median of measurements of length,width and superoinferior diameter of control and CAL group were 13.0 vs 13.8,5.0 vs 5.2 and 5.9 vs 6.2 mm, respectively ( P ＞ 0.05 ). (3) The CT value of the BB region in control group( median :42.6 HU ) was higher than that of CAL group( median: 13.0 HU) ( Z = - 7.061, P ＜0.01). The CT values of BB regions in patients with nonvisualized BB (median: -16.0 HU) were lower. The CT values of the BB regions in CAL group were negatively-correlated with Gensini scores( median:19.0) (r = -0.553, P ＜0.01 ). (4)The blood supply of BB and BB region was provided by right sinuatrial node artery ( SNA, 58.7%, 121/206 ), left SNA ( 35.9%, 74/206 ) or both SNAs ( 5.3%, 11/206 ).Conclusions DSCTCA could can show the anatomical characteristics of BB and its arterial supply. The serious the degree of CAL , the lower the BB display rate, and the higher the abnormal ECG incidence,which indicate that the occurrence of BB lesions is probably related to ischemia. Key words: Coronary disease; Tomograph,X-ray computed; Anatomy