title: Comparison of myocardial contrast echocardiography derived myocardial perfusion reserve with invasive determination of coronary flow reserve.
abstract: OBJECTIVE
  Invasive measurements of coronary flow reserve (CFR) by Doppler flow wire are an established method for determining coronary blood flow physiology. Myocardial contrast echocardiography (MCE) is a potential non-invasive method for quantifying myocardial blood flow (MBF). However, few studies have compared MCE-derived myocardial perfusion reserve (MPR) with Doppler flow wire-derived CFR, measured simultaneously in human subjects. This study aimed to correlate MCE-derived MPR with Doppler flow wire-derived CFR.
  
  
  RESULTS
  Ten patients with at least two angiographically normal coronary arteries underwent simultaneous invasive Doppler flow wire measurements and MCE imaging at rest and at peak hyperaemia. Hyperaemia was induced by intravenous adenosine infusion. Doppler-derived CFR was calculated as the ratio of hyperaemic to baseline average peak red blood cell velocity. MPR was calculated as the hyperaemic to baseline ratio of the following parameters: myocardial blood volume (MBV), myocardial microbubble velocity (MMV), and MBF. MCE was performed using real-time and triggered imaging with contrast infused intravenously by bolus and continuous methods. Regardless of whether the contrast was infused by bolus or continuous methods, Doppler flow wire-derived CFR had a stronger correlation with MPR derived by MBV (r=0.8, P=0.05) than with MPR derived by microbubble velocity (r=0.3, P>0.05) or MBF (r=0.4, P>0.05). Real-time imaging with continuous infusion provided better correlation with CFR than triggered imaging methods or bolus administration.
  
  
  CONCLUSIONS
  Myocardial perfusion reserve derived by real-time infusion MBV measurements correlates with Doppler flow wire-derived CFR. Therefore, MPR may be a potential surrogate for Doppler flow wire-derived CFR in patients with angiographically normal coronary arteries.
authors: Echocardiography Laboratory, St Louis University School of Medicine, FDT-14, St Louis, MO 63110, USA. bierigsm@slu.edu
authors: S Michelle
authors: SM
authors: Bierig
authors: Peter
authors: P
authors: Mikolajczak
authors: Steven C
authors: SC
authors: Herrmann
authors: Nicole
authors: N
authors: Elmore
authors: Morton
authors: M
authors: Kern
authors: Arthur J
authors: AJ
authors: Labovitz
mesh_terms: D000328:Adult; D003287:Contrast Media; D017023:Coronary Angiography; D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000473:pathology; D005260:Female; D053805:Fractional Flow Reserve, Myocardial; D006801:Humans; D008297:Male; D008875:Middle Aged; D015425:Myocardial Reperfusion; D009206:Myocardium / Q000473:pathology*; D013223:Statistics as Topic; D013318:Stroke Volume; D013599:Systole; D014463:Ultrasonography; D016277:Ventricular Function, Left
chemical_list: D003287:Contrast Media