The Heartflow Coronary Disease Progression Evaluation Study

Invasively measured fractional flow reserve (FFR) has proven to be useful in guiding coronary revascularization. Several studies have shown that it is justified to treat lesions with a value of 0.80 or lower and safe to defer from PCI in lesions with a value of >0.80. Recently, computational fluid dynamics have allowed FFR measurement from coronary computed tomography angiography images (FFRCT) with excellent diagnostic accuracy compared to invasive FFR.

FFRCT can also effectively guide revascularization safely deferring patient with FFRCT >0.80 from invasive angiography. In functionally non-significant lesions, computational fluid dynamic models in addition to CT plaque characteristics (low attenuation, positive remodelling, spotty calcification and napkin-ring sign) may be able to predict which lesions will become flow-limiting, causing clinical events in the future.

This study will evaluate disease progression in intermediate lesions (invasive FFR 0.81-0.90 at baseline) using FFRCT at 2 years and determine whether CT characteristics may help to identify lesions that are more susceptible for FFR decline. Additionally, we will correlate CT characteristics with coronary events (a composite endpoint consisting of all-cause mortality, target-vessel myocardial infarction and clinically driven target-vessel revascularization) up to 5 years after the baseline invasive FFR.