Rapid rest/stress regadenoson ungated perfusion CMR for detection of coronary artery disease in patients with atrial fibrillation

Abstract

Cardiovascular magnetic resonance (CMR) perfusion has been established as a useful imaging modality for the detection of coronary artery disease (CAD). However, there are several limitations when applying standard, ECG-gated stress/rest perfusion CMR to patients with atrial fibrillation (AF). In this study we investigate an approach with no ECG gating and a rapid rest/stress perfusion protocol to determine its accuracy for detection of CAD in patients with AF. 26 patients with AF underwent a rapid rest/regadenoson stress CMR perfusion imaging protocol, and all patients had X-ray coronary angiography. An ungated radial myocardial perfusion sequence was used. Imaging protocol included: rest perfusion image acquisition, followed nearly immediately by administration of regadenoson to induce hyperemia, 60 s wait, and stress image acquisition. CMR perfusion images were interpreted by three blinded readers as normal or abnormal. Diagnostic accuracy was evaluated by comparison to X-ray angiography. 21 of the CMR rest/stress perfusion scans were negative, and 5 were positive by angiography criteria. Majority results of the ungated datasets from all of the readers showed a sensitivity, specificity and accuracy of 80, 100 and 96%, respectively, for detection of CAD. An ungated, rapid rest/stress regadenoson perfusion CMR protocol appears to be useful for the diagnosis of obstructive CAD in patients with AF.

Trial registration: ClinicalTrials.gov NCT01710254.

Keywords: Atrial fibrillation; Cardiac perfusion; ECG gating; Myocardial perfusion imaging; Ungated cardiac MR.

Conflict of interest statement

Competing interests

The authors declare that they have no competing interests.

Figures

Fig. 1

The protocol for rapid regadenoson ungated CMR perfusion imaging is shown. Rest perfusion imaging was completed and stress agent dosing was administered immediately with stress perfusion imaging. Average scan time for the entire perfusion protocol was 4 minutes and 40 seconds ± 60 seconds.

Fig. 2

Rest and stress perfusion images showing inferior wall defect with corresponding coronary X-ray angiography of an example patient are shown. The patient is a 74 year old female with a history of hypertension who presented with syncope and chest pain, found to have onset of atrial fibrillation in the setting of a non-ST segment elevation acute myocardial infarction. (A) Rest perfusion image demonstrating mid inferior wall defect. (B) Stress perfusion image demonstrating mid inferior wall defect with septal wall extension. (C) Coronary X-ray angiography demonstrating chronic total occlusion of the mid right coronary artery. (D) Coronary X-ray angiography demonstrating distal right coronary artery filling via collaterals.

Fig. 3

Example ungated rest and stress perfusion images for each patient with obstructive CAD by X-ray angiography are shown. (A) A patient with a total occlusion of the posterior descending artery with an inferior wall stress perfusion defect. (B) A patient with three-vessel obstructive CAD with a matched anterior perfusion defect. (C) A patient with three-vessel obstructive CAD with a diffuse subendocardial perfusion defect. (D) A patient with obstructive lesions of the mid left anterior descending artery and first diagonal branch without associated perfusion defect (false negative study). (E) A patient with multiple obstructive lesions in the right coronary artery with a stress perfusion defect in the inferior wall and inferior septum.