| Part I: Contrastive study of cardiac computed tomography angiography and invasive coronary angiography in the diagnosis of myocardial bridgeBackground: Myocardial bridging(MB)is a congenital abnormality.A coronary artery is underwent a "tunnel" in the form of a "bridge" in the myocardium.The intracoronary coronary artery is called mural coronary artery(MCA).This mutation causes the blood vessels to be compressed in the systolic phase,and the associated hemodynamic changes may lead to angina,myocardial ischemia,acute coronary syndrome,left ventricular dysfunction,arrhythmias,and even sudden cardiac death.Due to changes in blood shear force,the coronary artery near the compression zone is more prone to atherosclerosis.At present,invasive coronary angiography(ICA)is the most commonly used technique in the diagnosis of myocardial bridge,but the examination technique will cause some trauma to the patient,and the high radiation,high cost and infection risk are limit.The growing development of computed tomography angiography(CCTA)has become a valuable tool for analyzing coronary artery dissection and patency.Its noninvasive characteristics,making it a great potential for the diagnosis of myocardial bridge,and there is need for further study to enable patients to benefit from it.Subjects and methods: A total of 243 outpatients and inpatients with 64-slice spiral CT coronary angiography and coronary angiography were collected from July 2015 to July 2018 in Hanting District People's Hospital including 126 male,117 female patients,aged about 64.3 ± 10.1(mean ± standard deviation)years.Myocardial bridge and mural coronary artery detection rate of CCTA and ICA were compared.Results: Of the 207 patients,98 were diagnosed with ICA and 145 were negative.The positive rate of CCTA was 100%(98/98),the negative rate was 96.55%(140/145),the positive predictive value was 95.15%(98/103),the negative predictive value was 100%(140/140),the coincidence rate was 97.94%(238/243).?2=5.00,P=0.0625.The difference of myocardial bridge detection rate between CCTA and ICA was not statistically significant(P> 0.05).The MCA segments detection rate was 48.56%(118/243)in 64 slice spiral CT coronary angiography,including 12 in the anterior descending proximal branch,64 in the anterior descending middle branch,13 in the anterior descending distal branch,9 in the right posterior descending branch,11 in the middle branch,3 in the first diagonal branch,4 in the first blunt branch.ICA showed a total of 105 MCA segments.Its detection rate was 43.21%(105/243),including 11 in the anterior descending proximal branch,59 in the anterior descending middle branch,13 in the anterior descending distal branch,7 in the right posterior descending branch,8 in the middle branch,3 in the first diagonal branch,4 in the first blunt branch.ICA detected 105 MCA of the same location of CCTA,ICA did not diagnose the remaining 13.Conclution:The detection rate of myocardial bridge between 64-slice spiral CT coronary angiography and invasive coronary angiography was no difference,and CCTA was noninvasive.Myocardial bridge occurs in the middle part of left anterior descending coronary had the highest incidence of middle descending descent.Part II: Study on the relationship between the depth or length of the mural coronary artery and the dynamic compression in the middle of left anterior descending branchBackground: Myocardial bridge(MB)is a congenital anomaly of coronary artery,which means the segment of the coronary artery passes through the myocardium.This abnormality can lead to myocardial ischemia,arrhythmia,and even death.In some previous studies,it has been shown that CCTA is effective in detecting MB and mural coronary artery(MCA),and MCA is most common in the middle of the left anterior descending artery.The aim of this study was to evaluate the correlation between the depth or length of the coronary artery and the dynamic compression in the left anterior descending artery(LAD)using CTA and ICA.Subjects and methods: 87 patients with CCTA diagnosed as left anterior descending branch of myocardial bridge and underwent ICA examination were enrolled in the hospital from July 2015 to July 2018 in Hanting District People's Hospital,Weifang People's Hospital.The depth and length of the mural coronary artery in the left anterior descending artery were measured with CTA.The ICA was used to calculate the degree of dynamic myocardial compression.The correlation between the depth and length of the mural coronary artery in the left anterior descending branch and the degree of dynamic compression of the coronary artery was then assessed.Results: A total of 87 patients were enrolled in the study.The most common MB-MCA depth was 2<d?3mm(n = 33,37.9%),and the dynamic compression degree was 50.15 ± 1.62%.The maximum degree of dynamic compression was in d>4 mm(72.84 ± 1.67%),and the lightest degree of dynamic compression was in 0<d?1mm(25.43 ± 1.38).The most common MB-MCA length was 10<l?15 mm(n= 37,42.5%),with the most severe dynamic compression(52.52 ± 9.73%).The degree of dynamic compression was 15 <l?20mm(49.87±16.86%).Fifty patients in 87 patients were randomized to 25 groups according to different MCA depths.Two-way analysis of variance were used to calculate the degree of dynamic compression in different MB-MCA depth and length.Depth main effect F=1542.91,P <0.01,the difference was statistically significant.Length main effect F=1.03,P = 0.41(> 0.05),the difference was not statistically significant.Depth X-length interaction F = 1.27,P = 0.29(>0.05),the difference was not statistically significant.Conclution: 1.The degree of dynamic compression of mural coronary artery is related to its depth 2.The degree of dynamic compression of mural coronary artery was independent of its length 3.There was no interaction between the depth and length of mural coronary artery on dynamic compression... |
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