Table 3 Key MR sequence and their utility in pre-operative evaluation for TAVI
Sequence | Purpose |
|---|---|
Three-plane localizer | Localize aortic valve plane |
Axial SSFP non-ECG gated without contrast | Identify potential ascending aorta and subclavian access sites, determine size, calcification, and presence of aneurysmal dilatation of aorta |
Breath held/free breathing 2D ECG-gated SSFP: Coronal Aorta, LVOT and Aortic Root | Evaluate aortic annulus, aortic valve structure, and sinus height Planimetry valve orifice area |
SSFP ECG gated images: short axis stack | Calculate ejection fraction, ventricular volumes and mass |
Breath held/free breathing phase contrast at aortic orifice | Calculate blood flow velocity, pressure gradient and flow volume across the aortic valve Calculate aortic regurgitant volume |
3-D Navigator assisted SSFP | Coronary ostia height Aortic diameter |
T2 Black Blood | Useful in presence of susceptibility artifacts from sternal wires or prosthetic valves |