Value of coronary stenotic flow velocity acceleration in prediction of angiographic restenosis following balloon angioplasty

Introduction: Quantitative angiographic assessment after balloon angioplasty is a poor predictor of immediate and long-term outcome. However, the measurement of blood flow velocity during angioplasty has been proved clinically useful. Aims: To analyse the value of the maximal stenotic flow velocity and the presence of stenotic flow velocity acceleration (aSV) for the long-term outcome after balloon angioplasty. Methods and Results: Patients undergoing single lesion angioplasty within the DEBATE trial were included. aSV was defined as acceleration in the stenotic coronary flow velocity >50% baseline velocity assessed at a reference site of the target vessel. After balloon angioplasty diameter stenosis, minimal lumen diameter (MLD) and coronary flow velocity reserve were similar between the aSV (n = 54) and non-aSV group (n = 125). At follow-up, the aSV group had a higher restenosis rate (52% vs 30%, P=0·006) The presence of aSV was the strongest independent predictor of restenosis (OR 3·08, 95% CI 1·35 to 7.05, P=0·008). The best predictive cut-off value of SV was 101 cm. s^-1 (sensitivity of 46%, specificity of 81%, positive predictive value of 85% and a negative predictive value of 58%). Conclusion: Following angioplasty, SV appears to be exquisitely sensitive to the changes experienced at the treated area without depending on the status of the microcirculation.