RT Journal Article
SR Electronic
T1 18 Baseline coronary flow varies with normal cardiac catheter laboratory stimuli
JF Heart
JO Heart
FD BMJ Publishing Group Ltd and British Cardiovascular Society
SP A10
OP A10
DO 10.1136/heartjnl-2016-309588.18
VO 102
IS Suppl 4
A1 Bhavik N Modi
A1 Howard Ellis
A1 Satpal Arri
A1 Matthew Lumley
A1 Natalia Briceno
A1 Rupert Williams
A1 Brian Clapp
A1 Simon Redwood
A1 Michael Marber
A1 Divaka Perera
YR 2016
UL http://heart.bmj.com/content/102/Suppl_4/A10.1.abstract
AB Introduction Fractional Flow Reserve (FFR) is a pressure-derived estimate of coronary flow impairment during maximal and constant hyperaemia provided by an adenosine infusion, when flow and pressure approximate linearly. The need for adenosine-induced hyperaemia has led to development of a stenosis severity index measured at rest, Instantaneous Wave Free Ratio (iFR). Its use and proposed applicability to serial/diffuse disease has relied on assumptions that coronary flow at rest is maintained at constant levels. This study aimed to assess variability of resting coronary flow with normal Catheter laboratory stimuli.Methods Forty-Seven elective patients were recruited with a variety of coronary artery disease severity (mean FFR: 0.883; SD: 0.938). Simultaneous intracoronary pressure (Pd) and Doppler Average Peak Flow Velocity, APV(U), recordings were made. These were made both at rest and just prior to supine bicycle exercise or intravenous adenosine infusion.Results Average peak flow velocity varied significantly between measurements at rest and just prior to commencement of adenosine or supine bicycle exercise (18.1765cm/s vs. 19.4689cm/s, p 0.002). This was without significant change in haemodynamics (Table 1).Conclusion Resting coronary flow appears to vary significantly with normal Catheter Laboratory stimuli, such as simple warnings, irrespective of haemodynamic status.View this table:Abstract 18 Table 1 Table illustrating changes in Heart Rate, Systolic Blood Pressure (SBP), Ratio of distal coronary pressure to proximal aortic pressure (Pd/Pa) and Average Peak Coronary Flow Velocity (APV)