The pressure ratio in the resting phase of the cardiac cycle is a newly Introduced procedure for the assessment of coronary stenoses based on pressure measurement without adenosine. It generated interest with over 1500 comparisons with the FFR since its introduction at TCT 2011. The discrepancies between the two methods have been attributed to the retrospective design, different algorithms for measuring IFR failure electrocardiogram to determine the period without waves, etc. It took a rigorous prospective study to establish the clinical value of the iFR.
Patients were treated according to iFR and FFR value. If the IFR was <0.85, they were treated; with a value between 0.86 and 0.93, they underwent FFR to decide and, with a value >0.94, they were not treated. The pressure ratio in the resting phase of the cardiac cycle (iFR) is a newly introduced procedure for the assessment of coronary stenoses based on pressure measurement without adenosine. It generated interest with over 1500 comparisons with the FFR since its introduction at TCT 2011. The discrepancies between the two methods have been attributed to the retrospective design, different algorithms for measuring iFR, electrocardiogram failure to determine the period without waves, etc. It took a rigorous prospective study to establish the clinical value of the iFR. Patients were treated according to iFR and FFR value. If the IFR was <0.85, they were treated; with a value between 0.86 and 0.93, they underwent FFR to decide and, with a value >0.94, they were not treated. Included for analysis were 308 patients with 354 stenoses. The best cutoff point for the iFR turned out to be 0.89 with a specificity of 87.5%, sensitivity of 72.2%, positive predictive value of 78% and negative predictive value of 83.7%. The hybrid approach (iFR / FFR) increased the sensitivity, specificity and positive and negative predictive value of the method (94.8%, 86.1%, 91.1% and 91.7% respectively).
Conclusions: iFR appropriately classifies stenoses in 88.2% of lesions between the values of 0.85 and 0.94. The optimal cutoff for the iFR to identify lesions with FFR <0.8 was 0.89.
Javier Escaned.
2013-05-23
Original title: Adenosine vasodilator independent stenosis evaluation II (ADVISE II).
