The reliability and feasibility of non-contrast adenosine stress cardiovascular magnetic resonance T1 mapping in patients on haemodialysis

Abstract

Background: Identifying coronary artery disease (CAD) in patients with end-stage renal disease (ESRD) is challenging. Adenosine stress native T1 mapping with cardiovascular magnetic resonance (CMR) may accurately detect obstructive CAD and microvascular dysfunction in the general population. This study assessed the feasibility and reliability of adenosine stress native T1 mapping in patients on haemodialysis.

Methods: The feasibility of undertaking rest and adenosine stress native T1 mapping using the single-shot Modified Look-Locker inversion recovery (MOLLI) sequence was assessed in 58 patients on maintenance haemodialysis using 3 T CMR. Ten patients underwent repeat stress CMR within 2 weeks for assessment of test-retest reliability of native T1, stress T1 and delta T1 (ΔT1). Interrater and intrarater agreement were assessed in 10 patients. Exploratory analyses were undertaken to assess associations between clinical variables and native T1 values in 51 patients on haemodialysis.

Results: Mean age of participants was 55 ± 15 years, 46 (79%) were male, and median dialysis vintage was 21 (8; 48) months. All patients completed the scan without complications. Mean native T1 rest, stress and ΔT1 were 1261 ± 57 ms, 1297 ± 50 ms and 2.9 ± 2.5%, respectively. Interrater and intrarater agreement of rest T1, stress T1 and ΔT1 were excellent, with intraclass correlation coefficients (ICC) > 0.9 for all. Test-retest reliability of rest and stress native T1 were excellent or good (CoV 1.2 and 1.5%; ICC, 0.79 and 0.69, respectively). Test-retest reliability of ΔT1 was moderate to poor (CoV 27.4%, ICC 0.55). On multivariate analysis, CAD, diabetes mellitus and resting native T1 time were independent determinants of ΔT1 (β = - 0.275, p = 0.019; β = - 0.297, p = 0.013; β = - 0.455; p < 0.001, respectively).

Conclusions: Rest and adenosine stress native T1 mapping is feasible and well-tolerated amongst patients with ESRD on haemodialysis. Although rater agreement of the technique is excellent, test-retest reliability of ΔT1 is moderate to poor. Prospective studies should evaluate the relationship between this technique and established methods of CAD assessment and association with outcomes.

Keywords: Coronary artery disease; End-stage renal disease; Feasibility; Haemodialysis; Myocardial ischaemia; Reliability; Reproducibility; Stress T1.

Fig. 1

T1 map analysis and segmentation of mid-ventricular slice (a) at rest and (b) during adenosine stress, based on definition of right ventricular insertion point (blue dot)

Fig. 2

Consort diagram

Fig. 3

Bland-Altman plots for test-retest reliability of (a) resting native T1, (b) stress native T1, (c) ΔT1; interrater agreement of (d) resting native T1, (e) stress native T1, (f) ΔT1; intrarater agreement of (g) resting native T1, (h) stress native T1, (i) ΔT1

Fig. 4

Scatter plots displaying correlations between (left) ΔT1 and age; (right) ΔT1 and glycosylated haemoglobin (HbA1c)

Fig. 5

Differences in myocardial stress T1 reactivity (ΔT1) between groups. ΔT1 was significantly lower in patients with coronary artery disease; diabetes mellitus compared to patients without these pathologies. Patient who previously had a kidney transplant displayed significantly higher ΔT1 compared to patients who had only been on dialysis