ABSTRACT
Objective To evaluate the potential correlation between coronary artery tortuosity caused by myocardial bridge and coronary atherosclerosis. Methods The data of 88 patients with suspected coronary heart disease in the Affiliated Hospital of North China University of Science and Technology during the period from March 2015 to June 2016 were retrospectively analyzed.Coronary artery tortuosity caused by myocardial bridge was diagnozed by computed tomography coronary angiography.Meanwhile,the contemporary data of patients diagnosed with coronary artery tortuosity without myocardial bridge were selected as the control group.The coronary atherosclerosis as well as coronary artery stenosis were observed,and clinical data including age,gender,hypertension,hyperlipidemia,diabetes,smoking history,family history,and body mass index(BMI) were collected and compared.The incidence of coronary atherosclerosis in terms of whole coronary artery,anterior segment of tortuosity,tortuosity segment,and posterior segment of tortuosity was compared firstly,followed by the comparisons of the differences in coronary artery stenosis degree in terms of anterior segment of tortuosity,tortuosity segment,and posterior segment of tortuosity.Finally,the differences of the incidence of coronary atherosclerosis in the complete MB group,incomplete MB group,and non-MB group with different degrees of tortuosity were compared.Results The incidences of coronary atherosclerosis on whole coronary artery(χ=15.565,P=0.000),anterior segment of tortuosity(χ=8.606,P=0.003),tortuosity segment(χ=13.475,P=0.000) and posterior segment of tortuosity(χ=4.314,P=0.038) in the MB group were significantly lower than those in the non-MB group.The incidences of mild stenosis in anterior segment of tortuosity(χ=6.988,P=0.008),tortuosity segment(χ=10.050,P=0.002),and posterior segment of tortuosity(χ=4.314,P=0.038) in the MB group were significantly lower than those in the non-MB group.However,the incidences of moderate and severe stenosis on anterior segment of tortuosity(χ=0.586,P=0.444),tortuosity segment(χ=1.356,P=0.244),and posterior segment of tortuosity were not significantly different between these two groups.The incidence of coronary atherosclerosis on anterior segment of tortuosity of mild(χ=13.526,P=0.000) and moderate tortuosity(Fisher exact probability,P=0.015) in the complete MB group was significantly lower than that in the non-MB group;however,the severe tortuosity was not significantly different(Fisher exact probability,P=0.155).The incidence of coronary atherosclerosis on anterior segment of tortuosity of mild tortuosity(χ=9.167,P=0.002) in the incomplete MB group was significantly lower than that in the non-MB group;however,no significant difference of moderate(Fisher exact probability,P=0.047) and severe tortuosity(Fisher exact probability,P=0.031) was identified between these two groups(P>0.0167).Finally,no significant difference of the incidence of coronary atherosclerosis on anterior segment of tortuosity of mild(χ=1.239,P=0.266),moderate(Fisher exact probability,P=1.000),and severe tortuosity(Fisher exact probability,P=1.000) was identified between the complete MB group and the incomplete MB group.Conclusions Compared with non-MB patients,patients with coronary artery tortuosity caused by MB(especially complete MB) tend to have lower incidences of coronary atherosclerosis and mild coronary stenosis.However,coronary artery tortuosity caused by MB is not correlated with moderate or severe coronary stenosis.
ABSTRACT
Objective To study the impact of myocardial bridge (MB)-mural coronary artery (MCA) on myocardial functions.Methods Totally 82 patients presenting with chest tightness and chest pain who were diagnosed with the MB in the left anterior descending artery by CT coronary angiography were enrolled as the MB group,in which the thickness and length of MB and the systolic stenosis degree of MCA were measured.In addition,82 healthy subjects,as confirmed by health check-up,were set as the control group.The age,gender,body mass index (BMI),heart rate (HR),smoking history,interventricular septal thickness,left ventricular posterior wall thickness,diameter of left atrium,left ventricular end-diastolic diameter,left ventricular end-systolic diameter,left ventricular ejection fraction,and the cases of E'/A'<1 were compared between MB group and control group.The potential correlations among the thicken/length of MB,the systolic stenosis degree of MCA and early diastolic peak strain rate(SRe)/late diastolic peak strain rate(SRa) were analyzed.Results The age (t=0.97,P=0.65),gender (χ=0.10,P=0.75),BMI (t=1.82,P=0.07),HR (t=0.87,P=0.39) and smoking history (χ=0.43,P=0.51) were not significantly difference between these two group.The interventricular septal thickness (t=1.54,P=0.13),left ventricular posterior wall thickness (t=1.47,P=0.14),diameter of left atrium (t=1.62,P=0.11),left ventricular end-diastolic diameter (t=0.49,P=0.63),left ventricular end-systolic diameter (t=1.29,P=0.20),and left ventricular ejection fraction (t=0.56,P=0.57) were also not significantly different between the normal and MB group.However,there was significant difference in the cases of E'/A'<1 (χ=38.22,P=0.00).The SRe (r=-0.97,P=0.00;r=-0.93,P=0.00)and SRa (r=-0.89,P=0.00;r=-0.90,P=0.00) the left ventricular anterior wall were negatively correlated with the thickness of MB and the systolic stenosis degree of MCA and were not correlated with the length of MB (r=-0.09,P=0.76;r=-0.13,P=0.66).Conclusions MB is not correlated with myocardial systolic function,but can affect myocardial diastolic function.When the MB thickness increases,the systolic stenosis degree of MCA increases,the myocardial diastolic function gradually decreases,but the MB length is not related to myocardial systolic function.