The association between fractional flow reserve (FFR) and dobutamine stress echocardiography (DSE) in real world stable angina patients is scant and controversial whereas no such comparison exists with instantaneous wave free ratio (iFR). The current retrospective study aimed to investigate the associations amongst these modalities in patients with stable coronary artery disease (CAD) and intermediate coronary lesions.
METHODS AND RESULTS:
We studied 62 consecutive stable angina patients who underwent DSE and subsequently coronary angiography with FFR (in all 62) and iFR (in 46/62 patients) assessment of intermediate single vessel lesions between 2014-2015. Using receiver-operating curves (ROC) we sought to identify the optimal FFR and iFR cut off points with the highest discriminative power to predict DSE result. Kappa coefficient was used to assess the agreement between FFR, iFR and DSE. Mean age of the study cohort was 63.5±12 years and 35 (56.5%) were males. Thirteen (21%) lesions were adjudicated as causing reversible ischemia on DSE. Using ROC (FFR predicting DSE result), the area under the curve was 0.952 (95% CI: 0.902 to 1), whereas for iFR was 0.743 (95%CI 0.560 to 0.927), p AUC comparison=0.03. Optimal FFR cut-off point predicting positive DSE was 0.80. There was a strong agreement between DSE and FFR (Kappa 0.682, p<0.001). There was only modest agreement between iFR and DSE (kappa 0.258, p=0.068) using a cut-off value of 0.9.
In patients referred for evaluation of stable CAD, there was good agreement between DSE and FFR (87%) but less so with iFR (71.7%).
Panoulas VF, et al. Association between fractional flow reserve, instantaneous wave free ratio and dobutamine stress echocardiography in patients with stable coronary artery disease. EuroIntervention. 2017 Oct 3. pii: EIJ-D-17-00594. doi: 10.4244/EIJ-D-17-00594. [Epub ahead of print] PMID:28966160