Author + information
- Dominik C. Benz,
- Christoph Gräni,
- Paola Ferro,
- Luis Neumeier,
- Michael Messerli,
- Oliver Gaemperli,
- Aju Paul Pazhenkottil,
- Philipp Kaufmann and
- Ronny Buechel
Background: The functional relevance of a coronary stenosis can be estimated by fractional flow reserve from coronary computed tomography angiography (CCTA). Since its calculation is a complex process with limited availability, the corrected contrast opacification (CCO) decrease has been proposed as a faster alternative with promising diagnostic accuracy. It has, nevertheless, not yet been investigated in comparison to positron emission tomography (PET) myocardial perfusion imaging (MPI). The aim of the present study was to assess the accuracy of CCO decrease to predict an abnormal relative flow reserve (RFR) as derived from the gold standard PET MPI.
Methods: The present retrospective study consists of 41 patients who underwent hybrid CCTA/PET-MPI with coronary artery disease (defined as luminal diameter narrowing ≥50%). Mean attenuation of the coronary lumen was measured before and after a stenosis and corrected to the aorta to calculate CCO. The difference between CCO before and after the stenosis was defined as CCO decrease. RFR was calculated by dividing the stress myocardial blood flow (MBF) of a coronary artery with a stenosis by the stress MBF in the reference vessel(s) without a coronary stenosis. An RFR below 0.69 was considered abnormal as previously defined.
Results: CCO decrease was successfully assessed in 73 vessels. After exclusion of 32 vessels due to lack of reference vessel (i.e. three-vessel disease or left coronary dominance), RFR was abnormal in 11 of 41 vessels (27%). The ROC curve analysis resulted in an AUC of 0.712 for CCO decrease to predict an abnormal RFR (p<0.05). An optimal cut-off for CCO decrease was identified at 0.166, resulting in a sensitivity, specificity, negative predictive value, positive predictive value and accuracy of 73%, 70%, 88%, 47% and 70%, respectively. Median RFR was significantly lower in vessels with an abnormal CCO decrease compared to vessels with a normal CCO decrease (0.69 vs. 1.02; p<0.05).
Conclusions: CCTA-derived CCO decrease predicts an abnormal RFR in PET MPI with moderate diagnostic accuracy. Its high negative predictive value may confer clinical implications in the diagnostic work-up of patients with a coronary stenosis.
Poster Hall, Hall C
Friday, March 17, 2017, 3:45 p.m.-4:30 p.m.
Session Title: Non Invasive Imaging: Expanding Clinical Applications
Abstract Category: 27. Non Invasive Imaging: CT/Multimodality, Angiography, and Non-CT Angiography
Presentation Number: 1161-242
- 2017 American College of Cardiology Foundation