Improvement in coronary haemodynamics after percutaneous coronary intervention: assessment using instantaneous wave-free ratio

• Type of Material: Article
• Authors: Sukhjinder S. Nijjer, Imperial College London; Sayan Sen, Imperial College London; Ricardo Petraco, Imperial College London; Rajesh Sachdeva, Emory University; Florim Cuculi, John Radcliffe Hospital; Javier Escaned, Hospital Clinico San Carlos; Christopher Broyd, Imperial College London; Nicolas Foin, Imperial College London; Nearchos Hadjiloizou, Imperial College London; Rodney A. Foale, Imperial College London; Iqbal Malik, Imperial College London; Ghada W. Mikhail, Imperial College London; Amarjit S. Sethi, Imperial College London; Mahmud Al-Bustami, Imperial College London; Raffi R. Kaprielian, Imperial College London; Masood A. Khan, Imperial College London; Christopher S. Baker, Imperial College London; Michael F. Bellamy, Imperial College London; Alun D. Hughes, Imperial College London; Jamil Mayet, Imperial College London; Rajesh K. Kharbanda, John Radcliffe Hospital; Carlo Di Mario, Imperial College London; Justin E. Davies, Imperial College London
• Language: English
• Date: 2013-12-01
• Publisher: BMJ PUBLISHING GROUP
• Publication Version: Final Published Version
• Copyright Statement: Published by the BMJ Publishing Group Limited.
• License: Creative Commons Attribution 3.0 Unported
• Final Published Version (URL): http://dx.doi.org/10.1136/heartjnl-2013-304387
• Title of Journal or Parent Work: HEART
• Volume: 99
• Issue: 23
• Start Page: 1740
• End Page: 1748
• Grant/Funding Information: SSN (G1100443) and SS (G1000357) are Medical Research Council fellows. RP (FS/11/46/28861), JED (FS/05/006) and Dr Francis (FS 10/038) are British Heart Foundation fellows. The study also received support from National Institute for Health Research (NIHR) Biomedical Research Centre based at Imperial College Healthcare NHS Trust and Imperial College London, UK.
• Keywords: ACUTE MYOCARDIAL-INFARCTION; MICROVASCULAR RESISTANCE; Cardiovascular System & Cardiology; BALLOON ANGIOPLASTY; PRESSURE MEASUREMENT; ARTERY STENOSIS; STENOSIS SEVERITY; INTRAVASCULAR ULTRASOUND; LESION SEVERITY; INTRACORONARY PRESSURE; Life Sciences & Biomedicine; Science & Technology; Cardiac & Cardiovascular Systems; FRACTIONAL FLOW RESERVE; CORONARY PHYSIOLOGY
• Research Categories: Health Sciences, Medicine and Surgery

Abstract

Objective: To determine whether the instantaneous wave-free ratio (iFR) can detect improvement in stenosis significance after percutaneous coronary intervention (PCI) and compare this with fractional flow reserve (FFR) and whole cycle Pd/Pa. Design: A prospective observational study was undertaken in elective patients scheduled for PCI with FFR ≤0.80. Intracoronary pressures were measured at rest and during adenosine-mediated vasodilatation, before and after PCI. iFR, Pd/Pa and FFR values were calculated using the validated fully automated algorithms. Setting: Coronary catheter laboratories in two UK centres and one in the USA. Patients: 120 coronary stenoses in 112 patients were assessed. The mean age was 63±10 years, while 84% were male; 39% smokers; 33% with diabetes. Mean diameter stenosis was 68±16% by quantitative coronary angiography. Results: Pre-PCI, mean FFR was 0.66±0.14, mean iFR was 0.75±0.21 and mean Pd/Pa 0.83±0.16. PCI increased all indices significantly (FFR 0.89±0.07, p<0.001; iFR 0.94±0.05, p<0.001; Pd/Pa 0.96±0.04, p<0.001). The change in iFR after intervention (0.20 ±0.21) was similar to ÄFFR 0.22±0.15 (p=0.25). ΔFFR and ΔiFR were significantly larger than resting ΔPd/Pa (0.13±0.16, both p<0.001). Similar incremental changes occurred in patients with a higher prevalence of risk factors for microcirculatory disease such as diabetes and hypertension. Conclusions: iFR and FFR detect the changes in coronary haemodynamics elicited by PCI. FFR and iFR have a signi ficantly larger dynamic range than resting Pd/Pa. iFR might be used to objectively document improvement in coronary haemodynamics following PCI in a similar manner to FFR.