- Oral presentation
- Open Access
Detection of haemodynamically significant coronary stenoses with k-t SENSE-accelerated Myocardial Perfusion MR Imaging at 3.0 Tesla - a comparison with fractional flow reserve
© Lockie et al; licensee BioMed Central Ltd. 2010
Published: 21 January 2010
k-space and time sensitivity encoding (k-t SENSE) has been used to improve temporal or spatial resolution of perfusion CMR against visual interpretation of x-ray angiography (XRA).
To compare high spatial resolution k-t SENSE CMR perfusion at 3 T against fractional flow reserve (FFR), the reference method for detection of flow-limiting coronary stenoses in the catheter laboratory.
Patients with known or suspected coronary artery disease awaiting coronary XRA were studied, undergoing a CMR scan <48 hrs before XRA.
k-t SENSE accelerated perfusion CMR was performed on a 3 T Philips Achieva system (saturation recovery gradient echo, repetition time/echo time 3.0 ms/1.0 ms, flip angle 15°, 5× k-t SENSE acceleration, 11 interleaved training profiles, effective acceleration 3.8, spatial resolution 1.1 × 1.1 × 10 mm3, 3 slices acquired at each RR interval). Data were acquired during adenosine hyperaemia and at rest (0.05 mmol/kg Gd-DTPA). FFR was measured in all vessels with >40% severity stenosis using a pressure sensor-tipped wire (Volcano®). FFR < 0.75 was considered to represent a haemodynamically significant lesion. FFR was calculated as (Pd - Pv)/(Pa - Pv), where Pa, Pv and Pd are simultaneous aortic, right atrial and distal coronary pressures measured during an intravenous infusion of adenosine at 140 μg/kg/min. Two experienced observers blinded to the results of the angiogram visually interpreted ischemia on CMR data as relative underperfusion of a sector within a slice or relative endocardial underperfusion compared with epicardial perfusion. The performance of visual analysis of CMR to detect flow-limiting coronary stenosis on angiography was determined. Interobserver variability was calculated using the k coefficient.
k-t SENSE accelerated high-resolution perfusion MR at 3 T accurately detects flow-limiting coronary artery disease as defined by FFR, with good inter-observer agreement. The high specificity of perfusion CMR in this study may be the result of the high spatial resolution at which endocardial dark rim artefacts are reduced.
This article is published under license to BioMed Central Ltd.