Acute QFR demonstrated a 93% classification agreement with staged QFR, 84% with staged FFR, and 74% with staged iFR for assessing nonculprit lesions in STEMI patients.
Observational (n=112)
Blinded core-lab analysis
Yes
Does acute quantitative flow ratio (QFR) assessment accurately evaluate nonculprit lesions in patients with STEMI compared to staged QFR, FFR, and iFR?
Acute QFR assessment of nonculprit lesions in STEMI patients shows very good diagnostic agreement with staged QFR and good agreement with staged FFR, supporting its potential utility for immediate functional evaluation.
Effect estimate: 93% agreement (95% CI 87-99)
OBJECTIVES: We evaluated the diagnostic performance of quantitative flow ratio (QFR) assessment of nonculprit lesions (NCLs) based on acute setting angiograms obtained in patients with ST-segment elevation myocardial infarction (STEMI) with QFR, fractional flow reserve (FFR), and instantaneous wave-free ratio (iFR) in the staged setting as reference. BACKGROUND: QFR is an angiography-based approach for the functional evaluation of coronary artery lesions. METHODS: This was a post-hoc analysis of the iSTEMI study. NCLs were assessed with iFR in the acute setting and with iFR and FFR at staged (median 13 days) follow-up. Acute and staged QFR values were computed in a core laboratory based on the coronary angiography recordings. Diagnostic cut-off values were ≤0.80 for QFR and FFR, and ≤0.89 for iFR. RESULTS: Staged iFR and FFR data were available for 146 NCLs in 112 patients in the iSTEMI study. Among these, QFR analysis was feasible in 103 (71%) lesions assessed in the acute setting with a mean QFR value of 0.82 (IQR: 0.73-0.91). Staged QFR, FFR, and iFR were 0.80 (IQR: 0.70-0.90), 0.81 (IQR: 0.71-0.88), and 0.91 (IQR: 0.87-0.96), respectively. Classification agreement of acute and staged QFR was 93% (95%Cl: 87-99). The classification agreement of acute QFR was 84% (95%CI: 76-90) using staged FFR as reference and 74% (95%CI: 65-83) using staged iFR as reference. CONCLUSIONS: Acute QFR showed a very good diagnostic performance with staged QFR as reference, a good diagnostic performance with staged FFR as reference, and a moderate diagnostic performance with staged iFR as reference.
Sejr‐Hansen et al. (Mon,) conducted a observational in ST-segment elevation myocardial infarction (STEMI) with nonculprit lesions (n=112). Acute Quantitative flow ratio (QFR) vs. Staged QFR, FFR, and iFR was evaluated on Classification agreement of acute QFR with staged QFR (93% agreement, 95% CI 87-99). Acute QFR demonstrated a 93% classification agreement with staged QFR, 84% with staged FFR, and 74% with staged iFR for assessing nonculprit lesions in STEMI patients.