ISSN 2996-8215
International Journal of Cardiology | Vol. 6, No. 1, January 2015 | pp. 1–8
DOI: 10.46882/2015/IJC/000070
Original Research Article
Diagnostic Accuracy of CT-Derived Fractional Flow Reserve in Intermediate Coronary Stenosis
Arjun Patel¹, Rohan Mehta¹, Vikram Singh²
¹Department of Cardiology, Post Graduate Institute of Medical Education and Research, Chandigarh, India
²Division of Cardiovascular Radiology, All India Institute of Medical Sciences, New Delhi, India
Abstract:
Computed tomography coronary angiography (CTCA) provides high structural accuracy for ruling out coronary artery disease (CAD) but lacks functional capacity to determine if intermediate anatomical stenoses induce myocardial ischemia. Fractional flow reserve computed non-invasively from CTCA datasets (FFR-CT) applies computational fluid dynamics to fill this gap. This prospective study evaluated the diagnostic accuracy of FFR-CT for identifying lesion-specific ischemia, using invasive FFR as the gold standard. We enrolled 110 symptomatic patients with a single intermediate coronary stenosis (30% to 70% lumen reduction on CTCA) who were scheduled for invasive coronary angiography and FFR testing. FFR-CT was processed off-line using specialized fluid software, with ischemia defined as an FFR-CT less than or equal to 0.80. On a vessel-based analysis (134 vessels total), invasive FFR confirmed ischemia in 42 vessels (31.3%). Non-invasive FFR-CT demonstrated a diagnostic sensitivity of 88.1% (95% CI: 74.4%–96.0%), a specificity of 85.9% (95% CI: 77.0%–92.3%), a positive predictive value of 74.0%, and an exceptional negative predictive value of 93.9% (95% CI: 86.3%–97.9%). The area under the receiver operating characteristic curve for FFR-CT was significantly superior to standard anatomical CTCA narrowing criteria alone (0.90 vs. 0.72, p < 0.001). Fractional flow reserve derived from computed tomography coronary angiography achieves excellent diagnostic accuracy and a high negative predictive value for identifying ischemia-producing intermediate lesions, presenting a reliable tool to minimize unnecessary diagnostic invasive examinations.
Keywords: Computed tomography coronary angiography, Fractional flow reserve, Computational fluid dynamics, Myocardial ischemia, Diagnostic accuracy, Intermediate stenosis
Received: October 10, 2014; Revised: November 24, 2014; Accepted: December 15, 2014; Published: January 18, 2015.