NON - INVASIVE FFR, THEORY

There is much work on non-invasive FFR with CCTA. It obviously have a useful role for the detection of significant CAD with CCTA, as current anatomical CCTA scans, only tells what you see based on computerise volumetric reconstruction. The average CCTA has a positive predictive value of 60-80% and a negative predictive value of 95%.
With the use non-invasive FFR, these numbers all become better. From what I can understand, the computer engineers and also the bio-engineers have become very good. They can estimate flow and pressures with the CCTA scans and colour code them. By so doing, they can induce hyperemia in the same way that we do in the angio room, using IV adenosine. They then measure the pressure induce in the central aorta, and also in the pressure and flow across any given stenosis seen on the CCTA. This can be made obvious using their colour coding techniques. I will try and illustrate this.







How smart of them. What we need now is clinical correlation and more data, so that we know that it can be easily reproducible. How I wish that our local boys with the CCTA, will embark on such a correlation program, to document our own numbers, regarding accuracy and predictive value.