Evaluation Of The Early Changes Of Right Heart Secondary To Copd With3.0T MRI: An Experimental Study

Purpose: To explore the value of cine magnetic resonance imaging(Cine-MRI) in assessment of cardiac morphology and function in healthpiglets.Methods: A total of15healthy piglets were enrolled into this study, andall of piglets were examined with fast imaging employing steady-stateacquisition (FIESTA) cine MRI sequence. And all of the MRI images weredealed on Segment software. CUS was also performed in all of the piglets.The correlationships were determined with the dimensions of left ventricularwall, end-diastolic left and right myocardial mass, right ventricularend-diastolic volume and end-systolic volume, dimension of pulmonary byCine-MRI and CUS.Results:(1) CMRI measured end-diastolic right myocardial mass,end-diastolic right myocardial mass, the ratio of end-diastolic right ventricularmyocardial mass to end-diastolic left ventricular myocardial mass, rightventricular end-diastolic long and short dimension, right ventricularend-diastolic volume, right ventricular ejection fraction, left ventricularejection fraction were10±1g,38±2g,0.25±0.03,51.4±3.8mm,26.8±2.9mm,,54±4ml,0.54±0.04,0.53±0.06.(2) CMRI results: interventricularseptum:9.8±0.8mm, left ventricle posterior wall thickness:8.1±0.9mm,end-diastolic diameter of right ventricular:38.7±1.3mm, end-systolic volumediameters of right ventricular:27.6±1.9mm, dimension of pulmonary:18.9±1.1mm; CUS results: interventricular septum:9.3±0.5mm, leftventricle posterior wall thickness:9.1±0.9mm, end-diastolic diameter of right ventricular:36.7±1.3mm, end-systolic volume diameters of rightventricular:24.3±2.5mm, dimension of pulmonary:16.3±1.2mm; theresults of the two technologies has good correlation (r=0.976,0.860,0.849,0.699and0.720, respectively, all P<0.05).Conclusion: CMRI could evaluate the morphology and function of rightventricular (RV) and left ventricular (LV) invasively in piglets. Objective: Explore3.0T MRI to evaluation of the early changes ofcardiac function and ventricle thickness secondary to COPD.Materials and Methods: Fifteen piglets were prospectively used tomodel early COPD by papain and Elastase injected into pig. On0,5th,10th,15th and20th weekend after the beginning of the modeling, all of piglets wereexamined with fast imaging employing steady-state acquisition (FIESTA)cine MRI sequence. And measurement of cardiac function parameters,interventricular septum thickness, right ventricular end-diastolic volume,end-diastolic right myocardial mass, the ratio of end-diastolic right ventricularmyocardial mass to end-diastolic left ventricular myocardial mass, dimensionof pulmonary, and statistically analyzed to determine which diameter couldfollow-up diagnostic COPD.Results:(1) During the progress from lung normality to early COPD,end-diastolic right myocardial mass and the ratio of end-diastolic right ventricular myocardial mass to end-diastolic left ventricular myocardial masshas increased, and there were significant differences between lung normalityand15th、20th(all P<0.05); interventricular septum slightly thickened, but therewere no significant difference(all P>0.05); left ventricular myocardial massand the dimension of pulmonary were no significant difference(all P>0.05).(2)During the progress from lung normality to early COPD, right ventricularejection fraction and left ventricular ejection fraction were no significantdifference (all P>0.05), but right ventricular end-diastolic volume wassignificant differences between lung normality and20th(all P<0.05).(3)During the progress from lung normality to early COPD, right ventricularmyocardial mass was correlated with lung function index (r=0.422,0.381,0.360,0.262, respectively; all P<0.05); and the ratio of rightventricular myocardial mass to left ventricular myocardial mass wascorrelated with lung function index (r=0.401,0.350,0.357,0.283, respectively;all P<0.05); and right ventricular end-diastolic volume were correlated withinspiratory airway resistance, functional residual capacity, total lung capacity(r=-0.343,-0.343,-0.259, respectively; all P<0.05), but not correlated withexpiratory airway resistance (r=-0.208, P>0.05).Conclusion: CMRI can be used to assess cardiac function andmorphology changes in early COPD； right ventricular end-diastolic volume,right ventricular myocardial mass, end-diastolic right myocardial mass andthe ratio of end-diastolic right ventricular myocardial mass to end-diastolicleft ventricular myocardial mass has important value to assess right heartsecondary to early COPD.