Aims: The aim of this study was to investigate the prognostic value of fractional flow reserve (FFR) and a novel index (the D-index) of residual diffuse disease after intravascular ultrasound (IVUS)-guided second-generation drug-eluting stent (DES) implantation.
Methods and results: We evaluated 201 patients (201 lesions) who underwent IVUS-guided second-generation DES implantation in the left anterior descending artery with pre- and post-intervention physiological evaluations. Post-intervention hyperaemic pullback pressure recording was used to quantify residual diffuse disease using the novel D-index, defined as the difference between the distal stent and the far distal FFR values divided by distance. Clinical outcomes were assessed by vessel-oriented composite endpoints (VOCE) and major adverse cardiac events (MACE). The incremental discriminant and reclassification abilities of far distal FFR or D-index for VOCE and MACE were compared. Post intervention, far distal FFR and D-indices were significantly lower in vessels with VOCE. The optimal far distal FFR and D-index cut-off values for VOCE and MACE were 0.86 and 0.017 cm, respectively. Although both indices remained significant predictors of VOCE, only the D-index proved to be a significant predictor of MACE and significantly improved the incremental reclassification ability for MACE.
Conclusions: Residual diffuse disease assessed by the D-index after IVUS-guided second-generation DES implantation can help to predict both VOCE and MACE, while far distal FFR can help to predict VOCE specifically.