6114Indications, procedural parameters, complications and consequences of fractional flow reserve measurements in a multicenter cohort
Authors: Troebs M , Marwan M , Gaede L , Feyrer J , Nazli B , Moellmann H , Giesler T , Rittger H , Pauschinger M , Rudolph T , Moshage W , Brueck M , Achenbach S 
Published: October 2019

Abstract

Background
Determination of the Fractional Flow Reserve (FFR) has become part of routine clinical practice. Contemporary clinical use, consequences as well as complications in consecutive, large cohorts have not been thoroughly investigated. We report the results of the prospective Fractional Flow Reserve Fax Registry F (FR2) conducted in Germany.

Purpose
To systematically analyze indications, procedural parameters, complications and consequences of intracoronary pressure measurements in a large contemporary cohort.

Methods
Data of 2000 consecutive patients undergoing clinically indicated FFR, iFR or pd/pa measurements in 8 interventional centres in Germany were prospectively collected in a systematic fashion. Data included basic patient characteristics, procedural aspects of intracoronary pressure measurements, associated complications, visual stenosis degree, measurement results and treatment decisions.

Results
Mean patient age was 68±11 years, 73% of patients were male. Of all patients, 300 patients (15%) had an acute coronary syndrome (STEMI: 9; NSTEMI: 94; unstable angina: 197) and 1002 patients (50%) had undergone previous revascularization. A mean of 1.7±0.9 measurements were performed per patient, for which an average of 1.02 pressure wires were required (more than 1 wire in 64 patients). For all 3373 interrogated lesions, median stenosis degree was 60%. Vasodilator-free measurements were performed in 415/3373 cases (12%, iFR: 346; pd/pa: 69). For vasodilation, i.v. adenosine was used in 396 cases (13%), i.c. adenosine in 2628 cases (87%), and other drugs in 10 cases (0.3%). Measurement was performed before potential revascularization in 3232 cases (96%) and during or following PCI in 141 cases. In 2958 lesions analyzed by FFR, mean FFR was 0.87, with 588 FFR measurements ≤0.80 (19.8%). Median FFR values were higher for i.c than i.v. adenosine administration (0.88 vs. 0.84), but not significantly different after adjustment for stenosis degree. In 735 cases (20.2%), intracoronary pressure measurement was followed by revascularization measures, while in 2637 cases (79.8%), no revascularization or no further revascularization was performed. In 36 out of 117 stenoses visually estimated to be ≥90%, revascularization was deferred following pressure measurement (31%). In 75 out of 2958 lesions analyzed by FFR, revascularization was performed even though FFR was >0.80 (3%). Severe complications (vessel dissection or occlusion) occurred in 5 out of 2000 patients as a consequence of intracoronary pressure measurement, resulting in death of 1 patient.

Conclusion
In clinical practice, the majority of intracoronary pressure measurements are performed in stenoses of intermediate angiographic severity and revascularization is deferred in approximately 80% of lesions. Vasodilator-free measurements are infrequent and route of adenosine administration has no effect on results. Complication rate is low but not negligible.

Acknowledgement/Funding
Abbott Vascular