The Left Ventricular Function And Hemodynamic Changes Of Coronary Artery With Transthoracic Doppler Echocardiography In Diabetic Patients

Objectives: To analyze the changes of the left ventricular(LV) function in diabetes mellitus at rest by color Doppler Echocardiography, so as to realize its pathological and physiological changs.Methods: After detecting 36 DM patients and 24 healthy subjects with routine echocardiography, transmitral inflow velocity Ep and Ap were obtained from the apical long-aixs view using Pulse Doppler Echocardiography and Ep /Ap was calculated. From the same apical long-axis view, peak systolic velocity(Vs), peak early diastolic velocity(Ve) and peak late diastolic velocity(Va) of posterior mitral annulus were obtained using PW-DTI, then Ve/ Va and Ep/ Ve ratio were calculated.Results: indexes of LV diastolic function: the ratio Ep /Ap,Ve/ Va and Ep /Ve between DM group and normal group are all significantly different(P<0.05); if taking Ep/Ap<1,Ve/Va<1 as abnormal diagnosis standard respectively, the detection rate of LV diastolic dysfunction in 36 DM patients using PDE and PW-DTI are respectively 55.6%(20/36)and 83.3% (30/36);indexes of LV systolic function: EF,FS and Vs between DM group and normal group are neither significantly different.Conclusion: LV dysfunction is present in diabetic patients without overt cardiac disease, LV diastolic dysfunction happens earlier, myocardial ischemic contributes to the changes of heart function in diabetic patients.Part two: Hemodynamic changes of the distal left anterior descending artery by ultrasound in diabetic patientsObjectives: To observe and analyze the hemodynamic changes of the distal left anterior descending artery by transthoracic color Doppler echocardiography(TTDE) and to determine the relations between those changs and the microvascular impairments.Methods: 24 normal subjects and 31 patients were studied. The distal LAD flow signal was observed and the pulsed-Doppler velocity curve was recorded by TTDE. Systolic peak velocity(SPV), systolic velocity time integrity(VTIs), diastolic peak velocity(DPV), diastolic velocity time integrity(VTId), time from the beginning of diastole to diastolic peak velocity(TPVd), diastolic deceleration rate (DDR), diastolic deceleration duration(DDD) were measured.Results: The distal LAD flow signal could be observed in all cases of normal subjects and 29 cases in patients. SPV DPV had no significant difference between the patients and the controls. VTIs VTId TPVd and DDD were significantly lower in patients than those in controls(P<0.01), DDR was higher in patients than in controls(P<0.05).Conclusion: the intramyocardial microvascular impairments in diabetic patients may affect the flow dynamics of epicardial coronary artery. The increased microcirculation resistance and decreased coronary perfused capacity may contribute to the changes. Monitoring of The distal LAD flow velocity by TTDE was useful in early detecting latent myocardial ischemia in diabetic patients. Part three: Hemodynamic changes of intramyocardial microvascular by ultrasound in diabetic patientsObjectives: To observe and analyze the hemodynamic changes of intramyocardial microvascular which is caused by intramyocardial microvasculopathy in diabetic patients using TTDE.Methods: 27 normal subjects and 50 patients were studied. The intramyocardial coronary artery flow signal of the left ventricular anterior wall, posterior wall, anterior lateral wall, anterior septum and the apical part was carefully observed, and the pulsed-Doppler velocity curve was recorded by TTDE. diastolic peak velocity(Vm), diastolic velocity time integrity(VTId), time from the beginning of diastole to diastolic peak velocity(TPVd), diastolic deceleration duration(DDD) were measured.Results: The intramyocardial coronary artery flow signal of the left ventricular anterior lateral wall and anterior septum was observed more easily. At rest, Vm in diabetic group is higher than that of normal group, and TPVd,DDD in diabetic group are all less than normal group, and there are notable differences(P<0.01)in the two groups. Among these, VTId in the intramyocardial coronary artery flow of the anterior septum is significantly less than normal group(P<0.01),but VTId in the left ventricular anterior lateral wall is just a little bit less than normal group,and there is no statistical difference between them(P>0.05).Conclusion: intramyocardial microvasculopathy on the early stage of diabetic patients may affect the flow dynamics of intramyocardial microvascular, and lead to myocardial ischemia impairments when no any coronary pathological changes exist in diabetic patients. TTDE offers a good measure in early detecting latent myocardial ischemia in diabetic patients.