iFR pullback accurate in predicting tandem, diffuse coronary disease
Instantaneous wave-free ratio pullback may predict the physiological outcome of PCI with a high degree of accuracy in tandem and diffuse coronary disease.
According to results published in JACC: Cardiovascular Interventions, the availability of instantaneous wave-free ratio (iFR) pullback altered revascularization procedure planning in nearly one-third of patients compared with angiography alone.
“An iFR pullback recording provides a physiological map of lesion severity along the length of a vessel and can be used to predict the physiological outcome post-virtual PCI with a high degree of accuracy,” Yuetsu Kikuta, MD, from Imperial College London and Hammersmith Hospital NHS Trust in London and the Fukuyama Cardiovascular Hospital in Fukuyama, Japan, and colleagues wrote in the study background. “However, until recently, the ability to generate an iFR pullback recording was only possible using offline computer algorithms that limited real-world clinical applicability.”
To evaluate the accuracy of iFR pullback measurements to predict outcomes after PCI and to quantify how often iFR pullback alters PCI strategy in real-world clinical settings, Kikuta and colleagues conducted a study of patients with angiographically intermediate tandem and/or diffuse lesions from the iFR GRADIENT registry.
According to the study, operators were asked to submit their procedural strategy after angiography alone and then after iFR pullback measurement, incorporating virtual PCI and post-PCI iFR predictions. The researchers then repeated iFR assessment and compared the actual vs. predicted post-PCI iFR values.
The researchers measured paired pre- and post-PCI iFR in 134 vessels from 128 patients. Predicted post-PCI iFR calculated online was 0.93 ± 0.05, observed actual iFR was 0.92 ± 0.06 and iFR pullback predicted the post-PCI iFR outcome with 1.4 ± 0.5% error, Kikuta and colleagues wrote.
Compared with angiography alone, after iFR pullback, decision-making was changed in 31% of patients and was associated with a reduction in lesion number (0.18 ± 0.05 lesion per vessel; P = .0001) and length (4.4 ± 1 mm per vessel; P < .0001).
According to an editorial comment from Cardiology Today’s Intervention Editorial Board Member Morton J. Kern, MD, and Arnold H. Seto, MD, MPA, both from the Veterans Administration Long Beach Healthcare System and the University of California, Irvine, the study reinforces that elucidation of the lesion significance by physiology as opposed to reliance on the operator’s subjective observation can prevent excess stenting, and changes practice.
“IFR pullback coregistered to the angiographic images with PCI planning is one [of] the biggest advances in the interventional physiology community in recent years,” they wrote. “Looking into the future, we believe that the coregistration of a pressure pullback approach will be routinely incorporated into all physiology and imaging procedures.” by Dave Quaile
Disclosures: The study was funded by Volcano-Phillips and the National Institute of Health Research Imperial Biomedical Research Center. Kern reports he is a consultant and speaker for Abbott/St. Jude Medical, ACIST Medical Systems, Heartflow, Opsens and Philips/Volcano. Kikuta reports he consults for Philips/Volcano. Seto reports he is a speaker for ACIST Medical Systems and Phillips/Volcano. Please see the study for a list of the other authors’ relevant financial disclosures.