Background: A single guide wire, RADI Analyzer^TMhas advantage for evaluating coronary heart disease by simultaneous measurement of pressure and coronary flow reserve(CFR). We studied feasibility of this single guide wire for evaluating of coronary flow reserve.
Methods: In 24 coronary artery lesions(LCA=21, RCA=3) with 18 patients(59짹11 yrs, M=13) were studied. All patients had experienced chest pain(SA=3, UA=11, AMI=4). Both normal and stenotic vessels were included. A pressure-temperature sensor-tipped 0.014-inch guide wire(RADI Analyzer^TM) and 0.014-inch Doppler guide were introduced at distal site of lesions. With 4mL of saline at room temperature used as an indicator, by hand-injection, thermodilution curves in coronary artery were obtained in triplicate, both at baseline and at continous infusion of intracoronary(IC) adenosine(240關g/min) for inducing maximum hyperemia. After adequate curve-fitting, CFRthermo was calculated from the ratio of inverse mean transit times and compared with CFRdoppl calculated by the ratio of average peak velocity(APV) at maximum hyperemia induced by IC bolus injection of adenosine(24���48關g) and baseline. Also CFRthermo was compared with CFRdoppl calculated by the ratio of APV at maximum hyperemia induced by IC continuous infusion of adenosine(240關g/min) and baseline.
Result: In 24 coronary artery lesions, measured CFR was not different between CFRdoppl and CFRthermo(2.67짹1.22 vs 2.66짹1.02, P=0.97), CFRthermo showed good correlation with CFRdoppl estimated by IC bolus injection method (CFRthermo= 0.64CFRdoppl +0.94; r=0.79; P<0.001). In 21 coronary artery lesions, CFRthermo showed good correlation with CFRdoppl estimated by IC continuous infusion method(CFRthermo=0.30CFRdoppl+1.71; r=0.73; P<0.001).
Conclusion: This study shows the feasibility of measurement of CFR by coronary thermodilution method with one single guide wire and this single guide wire may be useful and facilitate for assessment of coronary hemodynamics by simultaneous measurement of FFR and CFR.