The Application Of Cardiac Magnetic Resonance T1 Mapping In Uremic Cardiomyopathy

Objective:Patients with end-stage renal disease(ESRD)have the significantly higher risk of cardiovascular diseases.Patient’s heart abnormalities are known as uremic cardiomyopathy.T1 mapping is an emerging cardiac magnetic resonance imaging technique that allows quantitative assessment of myocardial T1 times,which reflect myocardial fibrosis.The aim of the study is to assess the value of T1 mapping in uremic cardiomyopathy.Materials and Methods:ESRD patients were recruited at Beijing Hospital from September to December in 2016.A total of 10 patients with ESRD and 12 healthy volunteers who were matched for age and sex were included in the study.Both groups underwent MR scan with Philips Achieva 3.0T TX magnetic resonance scanner.ECG gating technology and respiratory gating technology were applied for image acquisition.Short axis cine sequence was used to assess the left ventricular function parameters,including ejection fraction(EF),stroke volume index(SVI),left ventricular end diastolic volume index(LVEDVI),left ventricular end systolic volume index(LVESVI),left ventricular mass index(LVMI).After the T1 mapping sequence scan is complete,the T1 times image is automatically generated.The DICOM browser was used to set the region of interest(ROI)in the T1 times image.Native T1 times of different segments of the myocardium are measured.And the mean value of the data was calculated.Continuous variables of normal distribution were expressed as mean±SD and the difference between the two groups was compared using independent t test.Abnormal distribution data were expressed as median and quartile numbers,and the difference between the two groups was compared using the Mann-Whitney test.The One-Way ANOVA test was used to compare the differences between the native T1 times of different segments of myocardium.The differences between the two groups were compared by IBM SPSS 20.0.P value<0.05 was considered to indicate statistical significance.Results:LVMI,LVEDVI,LVESVI in ESRD group were significantly higher than those in control group(p<0.05).LVEF in ESRD group were significantly lower than that of control group(p<0.05).SVI was lower in ESRD group,however,the difference was not statistically significant(p>0.05).Compared with the control group,the native T1 times of the mid anterior wall,mid anteroseptal wall,mid inferoseptal wall,mid inferior wall and mid inferolateral wall in ESRD group were significantly higher(p<0.05)..The native T1 times of the mid anterolateral wall was higher in the ESRD group,but the difference was not statistically significant(p>0.05).The native T1 times of the basal anterior wall,basal anteroseptal wall,basal inferoseptal wall,basal inferior wall were significantly higher in ESRD group than these in control group(p<0.05).The native T1 times of the ’basal inferolateral wall and basal anterolateral wall were also higher in ESRD group,but the difference was not statistically significant(p>0.05).The native T1 times of ventricular septal myocardium in ESRD group was higher than that in other segments(p<0.05).While the native T1 times of the septal myocardium in the control group was also higher than other segments,the difference was not statistically significant.Conclusion:Left ventricular hypertrophy is a common appearance in the uremic cardiomyopathy.T1 mapping is a sensitive method to detect the changes of the myocardium and has a wide range of potential applications.