A New Method To Measure The Extend Of Coronary Tortuosity And Its Application

Objective: Coronary tortuosity can cause changes in coronary artery hemodynamics. The severity of coronary tortuosity is considered to be correlated with its hemodynamic influence. A new method for quantitating coronary tortuosity can provide favorable conditions for understanding the hemodynamic effects caused by coronary tortuosity.Methods: we obtained all images and clinic data from 188 patients who received coronary computed tomography scanning during 1st July 2014 to 31 th July 2014. After image post-processing,we extracted the medial axis of three main coronary vessel and analysed its coordinates on three dimensions. Then we calculated the tortuosity coefficient of coronary artery. We have proved its validity as an index which reflects the changes in morphology with simulated shapes.Simulations: Through the establishment of the left anterior descending coronary artery tortuosity model, we found that the tortuosity angle linear correlation with the tortuosity coefficient, The correlation coefficient R2=0.999. through this we demonstrated its validityResult: Of all patients the average age is 66.21 ± 10.92 years old. The youngest is 39 years old, and the oldest is 93 years old. 88 cases were male, 100 cases were female; 57 patients has a history of smoking; 22 patients has a history of smoking;. LAD average tortuosity coefficient TC3 DLAD :0.0906±0.0800; LCX average tortuosity coefficient TC3 DLCX :0.2368±0.2379; RCA average tortuosity coefficient TC3 DRCA :0.4242±0.3043. LAD :35 non-tortuosity patients(18.62%)combine with artery stenosis, 12 patients(12.77%) in which combine with significant stenosis; 45 tortuosity patients(23.94%) combine with stenosis, 21 patients(22.34%) in which combine with significant stenosis. LCX :14 non-tortuosity patients(7.45%) combine with coronary artery stenosis, 5 patients(5.32%) in which combine with significant stenosis; 16 tortuosity patients(8.51%) combine with artery stenosis,6 patients(6.38%) in which combine with significant stenosis. 18 non-tortuosity patients(9.57%) coronary artery stenosis, 5 patients(5.32%) in which significant stenosis; RCA :29 tortuosity patients(15.43%) combine with artery stenosis,7 patients(7.45%) in which combine with significant stenosis. Tortuosity group has a higher incidence of coronary artery stenosis than non-tortuosity group in three coronary. Average age: LAD: tortuosity group average age is 68.52±10.46, non-tortuosity group average age is 64.03±10.97. LCX: tortuosity group average age is 67.93±10.52, non-tortuosity group average age is 64.63±11.12. RCA: tortuosity group average age is 68.28±10.44, nontortuosity group average age is 64.28±11.08. The average age tortuosity group was significantly older than non-tortuosity group in all three coronaries.(P<0.05)Conclusion: We propose a new method for quantitating coronary tortuosity, based on computed tomography Coronary imaging. The results of the measurement will not be affected by projection plane,vessel length or other artificial factors. In this study, the mean tortuosity coefficient of the RCA is higher than the other two coronary arteries, patients with artery tortuosity have higher incidence of coronary artery stenosis, it shows that coronary tortuosity may be associated with coronary artery stenosis.