Author + information
- Alejandro Gutierrez-Barrios1,
- Santiago Camacho Freire2,
- Soledad Ojeda3,
- German Calle4,
- Jose Diaz2,
- Manuel Pan3 and
- Rafael Vázquez-García1
In this Study we evaluated the relationship and correlation between three adenosine-free indexes (Pd/Pa); contrast FFR (cFFR) and Pd/Pa after intracoronary nitroglycerine (0.2 mg) and 3cc of contrast (Pd/Pa-NTG-C) and fractional flow reserve with adenosine (FFR).
We conducted a multicenter prospective study including 95 patients with 110 intermediate coronary stenosis evaluated with pressure wire. Resting baseline Pd/Pa, Pd/Pa-NTG-C, cFFR and the fractional flow reserve with intravenous adenosine (FFR) were measured.
The most frequently studied vessel was the left anterior descending (54.1%) and the average angiographic stenosis was 54.5±14%. Resting Pd/Pa value was 0.91±0.07, Pd/Pa-NTG-C was 0.85±0.07, cFFR was 0.84±0.09 and FFR was 0.81±0.09. A strong correlation was found between FFR and the three indexes analyzed: Pd/Pa (r=0.8, p<0.001); cFFR (r=0.88, p<0.001) and Pd/Pa-NTG-C (r=0.87, p<0.001), the correlation between these indexes, including FFR, and the angiographic stenosis was weak (r≤0.4, p<0.05 for all). The ROC curves using a FFR≤0.80 showed an area under the curve (AUC) of 0.93 (95% CI 0.87-0.97, p<0.001) for resting Pd/Pa; 0.94 (95% CI 0.87-0.98, p<0.001) for cFFR and 0.96 (95% CI 0.89 – 0.99, p=0.019) for Pd/Pa-NTG-C. The optimal cutoff values for a FFR>0.8 of resting Pd/Pa, cFFR and Pd/Pa-NTG-C were >0.9, >0.85 and >0.86 respectively. These cutoff values were present in a 41.7%, 50.7% and 48.3% of the total lesions respectively and showed a negative predictive value (NPV) of: 83.9%, 84.5% and 97.6% respectively, a sensitivity of: 83%, 82.4% and 96.2% and a specificity of 85.5%, 92.5% and 89.1%. When the three indexes were positives according to these cutoff values the probability of a positive FFR was 97% and when Pd/Pa and Pd/Pa-NTG-C were positives the probability was 94%.
The cutoff values of the three adenosine-free indexes analyzed provides excellent capacity to predict the functional significance of coronary lesions. The Pd/Pa-NTG-C showed the better correlation to FFR and the higher NPV and sensitivity. These indexes could allow limiting the use of adenosine to obtain FFR.
IMAGING: FFR and Physiologic Lesion Assessment