Abstract 17192: 3T Myocardial Perfusion Imaging with Multitransmit Technology Compared to Coronary Angiography and FFR

Abstract

Background: Due to steady technical development cardiac magnetic resonance imaging has become a powerful tool to determine myocardial vitality, perfusion and function. In particular the new generation of 3T multitransmit MR scanner with higher field strength, better spatial resolution, improved homogeneity and a reduction of dielectric shading has the potential to increase the accuracy of first pass myocardial perfusion imaging. So far cardiac magnetic resonance perfusion imaging (CMRPI) on a 3T multitransmit MR scanner has not been evaluated against coronary angiography (CA) and/or measurements of the fractional flow reserve (FFR). Objective: To evaluate the predictive value of first pass perfusion MRI using 3T multitransmit technology in patients with significant and intermediate lesions using CA as well as FFR- measurements. Materials and Method: 111 patients with suspected coronary artery stenosis were investigated applying CMRPI on a 3T using multitransmission technology within ±5 days of CA. A high dose adenosine stress/rest perfusion protocol was used. After 3 minutes of adenosine infusion (170 µg · kg-1 · min-1 for 3 minutes), perfusion scans were performed (in-plane spatial resolution 2.97x 2.97mm, slice thickness 8mm; Achieva 3T Tx; Philips Healthcare; Netherlands). In patients with intermediate lesions (40-79%), FFR measurements (St. Jude; USA) were performed to assess functional relevance. Perfusion images were assessed visually. Interobserver disagreements were resolved by consensus in a joint session. Results: In 52 vessels revealing either a lesion > 80% on CA or a pathological FFR (< 0.75), adenosine induced stress perfusion deficits could be detected in 92 % (Sensitivity 92 %). In 281 vessels without pathological FFR or lesion < 40 % a perfusion defect could be excluded in 98 % (specificity 98 %). Using ROC analysis, CMPRI was found highly accurate up to an FFR threshold of 0.77. Conclusion: Using 3T multitransmit technology we could demonstrate that CMPRI is an excellent tool to assess the functional relevance of significant and intermediate coronary stenosis with a high specificity and sensitivity. CMPRI was highly accurate up to an FFR threshold of 0.77.