Author + information
- Cristiano Bezerra1,
- Fábio A. Pinton2,
- Breno Falcão3,
- José Mariani Jr.1,
- Carlos A. Bulant4,
- Gonzalo Talou5,
- Antonio Esteves Filh Esteves6,
- Pablo Blanco5 and
- Pedro A. Lemos7
- 1University of São Paulo - InCor HCFMUSP, São Paulo, São Paulo, Brazil
- 2InCor, São Paulo, São Paulo, Brazil
- 3InCor - HCFMUSP, São paulo, São Paulo, Brazil
- 4LNCC - MACC, Petrópolis - RJ, Rio de Janeiro, Brazil
- 5LNCC, Petrópolis, Rio de Janeiro, Brazil
- 6Hospital Sírio Libanês, São Paulo, São Paulo, Brazil
- 7Heart Institute-InCor, University of São Paulo, São Paulo, São Paulo, Brazil
Fractional flow reserve (FFR) and intravascular ultrasound (IVUS) imaging, respectively, are considered as the “gold standard” for functional and anatomical assessments of angiographic intermediate stenoses. Associating both in a single method could optimize diagnosis and treatment of coronary artery disease.
We enrolled patients with suspected chronic coronary disease who underwent IVUS and FFR evaluation by clinical indication. Three-dimensional coronary models were obtained from the integration between IVUS images and the spatial location of the IVUS catheter through fluoroscopy. Computational fluid dynamics was applied, introducing a new strategy to estimate computational FFR from three-dimensional IVUS (FFRIVUS). The performance of FFRIVUS in patients with intermediate stenoses was evaluated using conventional FFR with a pressure guidewire (FFRPW) as reference.
FFRIVUS was estimated in 34 arteries of 24 patients with intermediate lesions. The mean minimum luminal area evaluated by IVUS (MLAIVUS) was 4.14 ± 1.74 mm2, with mean plaque burden of 66 ± 10%. There was a significant correlation between the FFRIVUS and FFRPW (r = 0.79, p <0.01), with a mean difference of -0.008 ± 0.067. Considering FFR ≤ 0.80 as indicative of ischemia, the accuracy, sensitivity, specificity, positive and negative predictive values were respectively: 91%, 89%, 92%, 80% and 96%. The area under the receiver operating characteristic curve was 0.93 for FFRIVUS and 0.81 for MLAIVUS and 0.69 for maximum percent angiographic stenosis (AX%), with a gain in FFRIVUS performance compared to AX% (p < 0.05). No systematic nor proportional differences between FFRIVUS and FFRPW were demonstrated.
FFRIVUS is a new computational method that allows the evaluation of the functional significance of intermediate coronary stenosis in an accurate way, enriching the anatomical information of IVUS.
IMAGING: Cath Lab of the Future