Article Text
Abstract
Background Three-dimensional (3D) myocardial perfusion cardiovascular magnetic resonance (CMR) permits whole heart coverage and can establish an estimation of myocardium at risk and ischaemic burden. For invasive estimation of ischaemic burden, semi-quantitative angiographic scores including the Duke Jeopardy Score have clinical legitimacy as the magnitude of myocardium at risk due to severe coronary stenosis is associated with an adverse prognosis. The Duke Jeopardy score combines assessment of stenosis severity and location.
Objectives To determine the association between myocardium at risk defined by the Duke Jeopardy Score and 3D CMR perfusion imaging.
Methods 53 patients referred for angiography underwent rest and adenosine stress 3D myocardial perfusion CMR at 3Tesla (3D turbo gradient echo, flip angle 15, TR 2.0 ms/TE 1.0 ms, 12 slices of 5 mm thickness, in-plane resolution 2.3×2.3 mm2, 10-fold k-space and time k-t broad linear speed up technique acceleration with k-t principal component analysis). Volume of myocardial hypoperfusion was calculated by a blinded observer using with GTVolume software (GyroTools, Switzerland) with quantitative methods based upon adjusting the signal intensity threshold >2 SDs below the signal of remote myocardium. Volume of hypoperfusion was calculated by summation of the contiguous slices. Jeopardy score was calculated from the coronary angiograms to quantify the myocardium at risk. The coronary tree was divided into six segments of nearly equal myocardial perfusion (eg, left anterior descending artery, major diagonal branch, circumflex artery, major obtuse marginal branch artery, right coronary artery, and posterior descending artery). A score of 2 for each significant lesion was given. Vessels were analysed by a cardiologist blinded to CMR and clinical details and assigned a score ranging from 0 (no Jeopardy) to 12 (maximum Jeopardy).
Results 53 patients were scanned with 159 coronary vessels anaylsed. The mean percentage volume of hypoperfusion on 3D-CMR was 9.9% (±10.9). The mean Jeopardy Score was 4.0 (±3.9). The mean percentage volume of hypoperfusion for Jeopardy scores of 0, 6, 12 were 0, 13.1% and 36.7% respectively. Pearsons correlation coefficient showed a strong correlation (r=0.82, 95% CI 0.70 to 0.89) between the Jeopardy Score and volume of hypoperfusion on CMR (p<0.0001) (Abstract 099 figure 1).
Conclusion There is a strong correlation between myocardium at risk by invasive indices and volume of inducible ischaemia by dynamic 3D CMR whole heart perfusion imaging. 3D CMR perfusion imaging offers a non-invasive alternative method of detecting ischaemic burden and myocardium at risk for the purpose of serial studies, guiding revascularisation and risk stratification.
- Cardiac MRI
- myocardial perfusion imaging
- duke jeopardy score