Abstract: FR-PO1028
Reproducibility and Clinical Determinants of Stress T1-Mapping in Patients on Haemodialysis: A Feasibility Study
Session Information
- Hypertension and CVD: Clinical Outcomes, Trials
November 08, 2019 | Location: Exhibit Hall, Walter E. Washington Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Hypertension and CVD
- 1402 Hypertension and CVD: Clinical, Outcomes, and Trials
Authors
- Poli, Federica E., University of Leicester, Leicester, United Kingdom
- March, Daniel Scott, University of Leicester, Leicester, United Kingdom
- Gulsin, Gaurav S., University of Leicester, Leicester, United Kingdom
- Mccann, Gerry Patrick, University of Leicester, Leicester, United Kingdom
- Burton, James, University of Leicester, Leicester, United Kingdom
- Graham-Brown, Matthew P.M., University of Leicester, Leicester, United Kingdom
Background
Identification of coronary artery disease (CAD) in patients with end stage renal disease (ESRD) is challenging. Adenosine stress non-contrast native T1 mapping on cardiac MRI has been proposed as a method to assess myocardial blood volume changes. It has been shown to accurately detect obstructive CAD and microvascular dysfunction in the general population. However, it has never been tested in patients with ESRD, who have higher resting native T1 times compared to control subjects. This study assesses the potential of stress T1 mapping to identify myocardial ischaemia in patients on haemodialysis (HD).
Methods
124 patients underwent rest T1 mapping. 58 of them had stress scans. 10 patients had identical reproducibility scans within two weeks. Myocardial stress T1 reactivity was calculated as ΔT1=[(stress T1−rest T1)/rest T1]×100. Interstudy reproducibility, inter-observer and intra-observer variability were assessed using intraclass correlation coefficient (ICC), coefficient of variability (CoV) and Bland-Altman analyses. Differences between groups and correlations between T1 and clinical variables were assessed. Independent predictors of ΔT1 were examined on multivariate linear regression.
Results
There were no clinically relevant differences between baseline characteristics of patients undergoing rest only or rest and stress scans. Of the 58 patients who had stress scans, only one had an inadequate haemodynamic response to adenosine. All patients tolerated and completed the scan, with no adverse effects. Inter- and intra-observer variability of rest T1, stress T1 and ΔT1 were excellent (ICC >0.9). Interstudy reproducibility for rest and stress T1 was good (CoV 1.2% and 1.5%; ICC 0.79 and 0.69, respectively), but average for ΔT1 (CoV 27.4%, ICC 0.55). On multivariate analysis, CAD, diabetes and rest native T1 time were independent predictors of ΔT1 (β= -0.244, p=0.038; β= -0.326, p=0.008; β= -0.458; p<0.001, respectively).
Conclusion
Stress T1 mapping is a feasible, reproducible and well-tolerated technique in patients on HD. It has the potential to evaluate myocardial ischaemia secondary to obstructive epicardial CAD or microvascular dysfunction despite the elevated resting native T1 values in this population. However, the reproducibility of ΔT1 is sub-optimal.