Evaluation of splenic switch off in a tertiary imaging centre: validation and assessment of utility.
OBJECTIVE
Adenosine can induce splenic vasoconstriction (splenic switch-off, SSO). In this study, we aim to evaluate the utility of identifying a lack of SSO for detecting false-negative adenosine stress perfusion cardiac magnetic resonance (CMR) scans.


RESULTS
We visually analysed 492 adenosine stress perfusion CMR scans reported as negative in a cohort of patients with no previous history of coronary artery disease. A lack of SSO was identified in 11%. We quantified the phenomenon by drawing regions of interest on the spleen and comparing intensity between stress and rest scans, the spleen intensity ratio (SIR). Inter-rater agreement for qualitative determination of SSO was κ = 0.81 and inter-class correlation for quantitative determination of SSO was 0.94. The optimal threshold for SIR as an indicator of SSO was 0.40 (sensitivity = 82.5%, specificity = 92.3%, AUC = 0.91). 23 065 CMR scans and 9926 invasive coronary angiogram reports were retrospectively examined to identify patients with negative CMR scans who required coronary intervention in the subsequent 12 months (false negatives). We compared these scans with true positives who had positive adenosine stress perfusion CMR scans followed by coronary intervention. The rate of lack of SSO was 20.7% in the false-negative group versus 13.1% in true positives (P = 0.37).


CONCLUSIONS
The lack of SSO is prevalent, easily measureable, and has potential to improve on haemodynamic criteria as a marker of adenosine understress in CMR perfusion scans.
Barts and the London School of Medicine and Dentistry, Queen Mary University of London, Garrod Building, Turner Street, London E1 2AD, UK.
Alice
A
Hosking
Barts and the London School of Medicine and Dentistry, Queen Mary University of London, Garrod Building, Turner Street, London E1 2AD, UK.
Marinos
M
Koulouroudias
NIHR Cardiovascular Biomedical Research Unit at Barts, William Harvey Research Institute, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK.
Filip
F
Zemrak
NIHR Cardiovascular Biomedical Research Unit at Barts, William Harvey Research Institute, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK.|Institute of Cardiovascular Science, University College London, Gower Street, London WC1E 6BT, UK.|Barts Heart Centre, Barts Health NHS Trust, St Bartholomew's Hospital, West Smithfield, London EC1A 7BE, UK.
James C
JC
Moon
NIHR Cardiovascular Biomedical Research Unit at Barts, William Harvey Research Institute, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK.|Barts Heart Centre, Barts Health NHS Trust, St Bartholomew's Hospital, West Smithfield, London EC1A 7BE, UK.
Alexia
A
Rossi
NIHR Cardiovascular Biomedical Research Unit at Barts, William Harvey Research Institute, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK.|Barts Heart Centre, Barts Health NHS Trust, St Bartholomew's Hospital, West Smithfield, London EC1A 7BE, UK.
Aaron
A
Lee
NIHR Cardiovascular Biomedical Research Unit at Barts, William Harvey Research Institute, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK.|Barts Heart Centre, Barts Health NHS Trust, St Bartholomew's Hospital, West Smithfield, London EC1A 7BE, UK.
Michael R
MR
Barnes
NIHR Cardiovascular Biomedical Research Unit at Barts, William Harvey Research Institute, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK.|Barts Heart Centre, Barts Health NHS Trust, St Bartholomew's Hospital, West Smithfield, London EC1A 7BE, UK.
Redha
R
Boubertakh
NIHR Cardiovascular Biomedical Research Unit at Barts, William Harvey Research Institute, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK.|Barts Heart Centre, Barts Health NHS Trust, St Bartholomew's Hospital, West Smithfield, London EC1A 7BE, UK.
Francesca
F
Pugliese
NIHR Cardiovascular Biomedical Research Unit at Barts, William Harvey Research Institute, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK.|Institute of Cardiovascular Science, University College London, Gower Street, London WC1E 6BT, UK.|Barts Heart Centre, Barts Health NHS Trust, St Bartholomew's Hospital, West Smithfield, London EC1A 7BE, UK.
Charlotte
C
Manisty
NIHR Cardiovascular Biomedical Research Unit at Barts, William Harvey Research Institute, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK.|Barts Heart Centre, Barts Health NHS Trust, St Bartholomew's Hospital, West Smithfield, London EC1A 7BE, UK.
Steffen E
SE
Petersen
D000241:Adenosine; D016022:Case-Control Studies; D003287:Contrast Media; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging*; D005080:Exercise Test; D005188:False Negative Reactions; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008536:Meglumine; D008875:Middle Aged; D009942:Organometallic Compounds; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013154:Spleen / Q000098:blood supply*
D003287:Contrast Media; D009942:Organometallic Compounds; D008536:Meglumine; D000241:Adenosine; C072417:gadoterate meglumine
Adenosine; Cardiac magnetic resonance; Splenic switch-off; Stress CMR