Purpose
Aim of this study was to assess the diagnostic value of 128-DSCT for sizing of the aortic valve area (AVA).
Therefore cardiac CT scans of patients with severe AS that were scheduled for TAVI were analyzed retrospectively,
measuring AVA from different cardiac phases and comparing them to TTE results.
Specifically,
the best phases for sizing and image quality in different phases were analyzed.
Methods and Materials
Study population
44 patients (age 82.5 range: 69-92; 50% females) with severe aortic valve stenosis were examined with contrast enhanced ECG-gated 128-slice dual source CT (gantry rot.
0.28s) prior to transcatheter aortic valve implantation (TAVI) for procedure planning.
CT examination
Image acquisition was performed using 128-slice dual source CT (SomatomDefinitionTM Flash,
Siemens Healthcare,
Forchheim,
Germany)
For contrast enhancement 70 to 110ml of iopromide (Ultravist 370™,
Bayer Schering Pharma,
Berlin,
Germany) were injected via a cubital vein using an automatic injector at a flow rate between...
Results
Among the 44 patients 32 Patients were in Sinus rhythm,
the remaining 12 had atrial fibrillation.
Mean heart rate was 73 bpm (range 49-101).
Phase of best correlation
For the best correlation between CT and TTE (AVAbestcorr; r=0.94,
p=0.001),
the most frequently chosen phase was 35% of the RR-interval.
(11/44,
19%) as shown in Table1.
Phase of largest Aortic valve area
The largest AVA (AVAmax) was most likely to be found at 25% (17/44; 39%) of cardiac cycle in early to mid systole and far...
Conclusion
The phase with widest opening of the aortic valve was most likely to be found in early-to-mid systole at 20-25% of RR interval.
This was also the interval of the cardiac cycle,
where best image quality was achieved and is therefore the interval most suitable for AVA planimetry.
That accords to data previously published for 16- and 64-slice CT,
where 20-30% [1],
20-25% [2],
5-20% [3] and 12% [4] were suggested to be the phases of widest opening of aortic valve.
AVAmax showed a good...
References
1.
Bouvier,
E.,
et al.,
Diagnosis of aortic valvular stenosis by multislice cardiac computed tomography. European heart journal,
2006.
27(24): p.
3033-8.
2.
Lembcke,
A.,
et al.,
Quantification of aortic valve stenosis: head-to-head comparison of 64-slice spiral computed tomography with transesophageal and transthoracic echocardiography and cardiac catheterization. Investigative radiology,
2009.
44(1): p.
7-14.
3.
Ropers,
D.,
et al.,
Comparison of dual-source computed tomography for the quantification of the aortic valve area in patients with aortic stenosis versus transthoracic echocardiography and invasive hemodynamic assessment. The American...