Intracoronary Doppler- and quantitative coronary angiography-derived predictors of major adverse cardiac events after stent implantation

Background-Distal coronary flow velocity reserve (CVR) is significantly imp roved after a successful balloon angioplasty (PTCA). Furthermore. a postint erventional CVR >2.5 and a percent diameter stenosis (%DS) less than or equ al to 35% are predictive for a low incidence of major adverse cardiac event s (MACE) at 6 months of 16%. Similar results are lacking for coronary stent ing. Methods and Results-In 150 patients, baseline and hyperemic coronary flow v elocities were recorded with a Doppler guidewire distal to the target lesio n and in an unobstructed reference artery before and after PTCA, after sten ting, and at 6 months. Distal CVR and relative CVR (CVRrel) were calculated . Logistic regression and receiver operating characteristic analyses were a pplied to determine prognostic cutoff values of CVR, CVRrel %DS, and minima l lumen diameter separately and in combination to predict MACE at 6 months. After stenting, CVR (2.96 +/- 0.87 versus 2.40 +/- 0.7; P=0.001), CVRrel ( 1.02 +/- 0.24 versus 0.81 +/- 0.24; P=0.001), and minimal lumen diameter (2 .98 +/- 0.56 versus 2.11 +/- 0.74 mm, P=0.001) were significantly higher th an after PTCA. Thirty-three patients developed MACE. A postinterventional C VRrel>0,88 was the best single predictor of MACE, with an incidence of 6.8% , whereas the combination of a CVRrel>0.88 and a %DS less than or equal to 11.2% predicted an incidence of MACE of 1.5%. Conclusions-Measurement of CVRrel and %DS after stent implantation are best suitable to predict MACE at 6 months.