Long term effects of surgical and transcatheter aortic valve replacement on FFRCT in patients with severe aortic valve stenosis.

ABSTRACT

The long-term variations of fractional flow reserve derived from coronary computed tomography (FFRCT) after surgical (SAVR) or transcatheter (TAVR) aortic valve replacement in patients with severe aortic valve stenosis (AS) have not been investigated. A total of 25 patients with isolated, severe AS underwent coronary computed tomography with 3-vessel FFRCT analysis (Heartflow Inc.-Redwood City, California, USA) and measurement of total coronary volume (V), left ventricular mass (M) and their ratio (V/M) before and 6 months after SAVR or TAVR. A significant increase in V/M due to a decrease in left ventricular mass 6 months after intervention was observed, whereas total coronary volume did not change (coronary volume pre 2924.5 ± 867.9 mm3, coronary volume post 2844.2 ± 792.8 mm3, P = 0.158; LV mass pre 151.7 ± 40.7 g, LV mass post 127.3 ± 34.7 g, P < 0.001; V/M pre 19.5 ± 4.1 mm3/g, V/M post 22.7 ± 4.28 mm3/g, P = 0.002). FFRCT (expressed as area under the virtual pullback curve) remained constant. This proof-of-concept study showed that FFRCT was not subject to the confounding effect of left ventricular mass regression after SAVR or TAVR. Despite significant left ventricular remodeling at 6 months after AS treatment, FFRCT values remained constant. Further studies are needed comparing the performance of the different invasive and non-invasive coronary physiological indices in this patient cohort.