Evaluation Of Right Ventricular Function And Pulmonary Parenchymal Changes In Patients With Chronic Obstructive Pulmonary Disease By 256 Slice ICT

Objective:(1)To investigate the value of Multi-detector row spiral Computed Tomography(MDCT)in evaluating right ventricular function(RVF)in patients with chronic obstructive pulmonary diseases(COPD),(2)the application value of MDCT in pulmonary function changes in COPD patients,(3)To investigate the correlation between RVF,quantitative CT analysis and pulmonary function test(PFT)changes in patients with COPD.Method:86 subjects including 20 control subjects,66 COPD patients of this study.And according to the percentage of predicted value of the FEV1(FEV1 %),the COPD group was divided into mild(grade I)20 cases,moderate(grade II)20 cases,severe(grade III)16 cases and extremely severe(grade IV)10 cases.Coronary angiography was taken by 256 slice iCT with retrospective ECG gated,and Cardiac Scoring sequence was changed into lung high resolution CT in COPD groups.Coronary artery results,RVF parameters were obtained in all patients,high resolution lung images were obtained in all COPD patients.The differences of RVF parameters between normal control group and COPD group were compared.And the correlation between RVF,the ratio of low attenuation areas(LAA %)measured by quantitative CT,PFT.Also,the volume CT dose index(CTDIvol)and dose length product(DLP)were compared in of this two scanning sequences and whom underwent those two scanning sequences.Result:(1)All enrolled subjects had no significant coronary stenosis,MDCT findings of the RVF showed:the ratio of Right Ventricular End Systolic Volume to Body Surface Area(RVESV/BSA)of normal control group was higher than that of COPD extremely severe group;RV End Diastolic Volume(RV-EDV)of COPD groups was lower than that in normal control group,RV Ejection Fraction(RV-EF)of COPD mild and moderate group was higher than extremely severe group;RV Stroke Volume(RV-SV)of normal control group was higher than that of COPD extremely severe group,and the ratio of Pulmonary Artery Diameter to Aortic Diameter(PAD/AD)was lower than that group,PAD of normal control group was lower than that of COPD groups,the difference was statistically significant(P<0.05).Logistic regression showed that PAD between normal control group and COPD grade I,the Odds Ratio(OR)value was 1.265,P value was 0.026;RV-EDV/BSA between normal control group and COPD grade II: OR value was 0.025,P value was 0.037;RV-EF between normal control group and COPD grade II: OR value was 0.012,P value was 0.039.(2)LAA% in COPD groups showed that the proportion of right lung was significantly different(P value was 0.026)during grade II and grade I,but the LAA % of left lung and total lung was not statistically significant(P>0.05),LAA% compared in the rest of the COPD groups were statistically significant(P<0.05).The LAA% was negatively correlated with clinical pulmonary function test(PFT).The total LAA% had the strongest correlation with FEV1 %(r value was-0.902),which reflect the severity of COPD;and the correlation with FEV1/FVC was-0.767,which reflect the airway resistance.(3)The right ventricular function of COPD patients had some correlation with PFT.RV-ESV,RV-ESV/BSA,RV-EDV/BSA were positively correlated with FEV1% predicted value(r value was 0.350,0.477,0.365 and P value was 0.004,0.001,0.003,respectively).Quantitative CT analysis showed that RV-ESV/BSA、PAD、PAD/AD were correlated with LAA%(r value was-0.413,0.524,0.299,P value was 0.001,<0.001,0.014,respectively).The CTDIvol and DLP of whom underwent those two scanning sequences(P value was <0.001).Conclusion:(1)The data of the coronary angiography,the RVF and the lung images could be obtained in the same examination by 256 slice iCT.PAD is an early indication of impaired RVF in COPD patients,and PAD/AD may indicate the severity of right ventricular dysfunction in COPD patients.(2)The LAA% of quantitative CT analysis had a strong consistency with PFT,it has a great significance in the evaluation of the severity of COPD,especially in the unilateral lung parenchyma destruction in early COPD patients,with a better clinical value.(3)There was a certain correlation between LAA% and RVF.LAA% negatively correlated with RV-ESV/BSA and positively correlated with PAD and PAD/AD,MDCT can be used to evaluate the changes of RVF and pulmonary function in COPD patients and reduce the radiation dose.