Multislice computed tomography for bioresorbable scaffolds: the end of invasive diagnostic studies?

Original title: Multislice Computed Tomography Angiography for Non-invasive Assessment of the 18-Months Performance of a Novel Radiolucent Bioresorbable Vascular Scaffolding Device (ABSORB Trial). Reference: Koen Nieman et al. J Am Coll Cardiol, article in press.

Metal stents revolutionized coronary angioplasty procedures; however, they are permanent prosthetic devices that make re intervention difficult and prolongue thrombosis risk. This problem could be solved by the new bioresorbable scaffolds which provide initial support, but dissolve in time, re-establishing the integrity of native vessels. The absence of metal in these new scaffolds allows both angiography and fractional flow reserve by multislice tomography imaging. 

This study evaluated the midterm clinical, angiographical and functional results of ABSORB study patients assessed by multislice tomography. All patients included in this study were elective, received a standard technique PCI and mandatory dilation. Combined end point at 18 months was death, infarction and revascularization of ischemia driven target lesion.

From 101 patients included in the ABSORB study, 71 received a 64 slice tomography that evaluated, among others, the difference between minimal lumen and vessel reference, considering >75% as a significant value. Fractional flow reserve analysis was also tomography based (TAC FFR) using HeartFlow, Inc (Redwood City, CA) which, based on clinical and tomographic data, can simulate coronary flow and median pressure during hyperemia, taking 0.8 as cutoff value.

At 18 months, there were 3 non Q wave infarctions, (all related to procedures), 5 ischemia driven revascularizations and no deaths. The mean stenosis area resulted in 22.7% ± 22.4% in the quantitative analysis of tomography imaging and the TAC FFR resulted in 0.89 ± 0.06. No significant correlation was observed between stenosis area, minimal lumen and TAC FFR, which suggests systematic under estimation of the latter.

Conclusion: 

Events combined at 18 months from second generation Absorb scaffold implants resulted acceptable (7.9%) as well as angiographic permeability by multislice tomography. 

Editorial Comment: 

This study, that now appears distant from clinical practice, is a window to the future. No doubt, both scaffolding and tomography techniques need perfecting. However, soon enough we will be able to follow our PCI results (both anatomical and functional) in a non invasive way and in one single study.

SOLACI.ORG

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