Slow flow or no-reflow during the primary angioplasty is associated with a poor prognosis. The impact of adjuvant balloon inflation on infarct artery flow after successful primary stenting has not yet been studied. Therefore, we investigated the effect of adjuvant balloon inflation on infarct related artery flow after successful stenting in patients with acute myocardial infarction.

The changes in infarct artery flow before and after adjuvant balloon inflation were assessed in 46 patients with a first episode of acute myocardial infarction (pain duration > 12 hr) who underwent adjuvant balloon inflation after successful primary stenting. Infarct artery flow was evaluated by corrected TIMI frame count (CTFC).

After adjuvant balloon inflation, 20 patients (43%) showed a slower flow. The minimal lumen diameter became greater (3.0 > 0.5 mm vs. 3.2 > 0.5 mm, p=0.002) and the residual stenosis lessened (12.2 > 9.6% vs. 6.4 > 8.1%, p<0.001). There was no change in reference vessel diameter. CTFC was significantly increased after adjuvant balloon inflation (21.6 > 11.5 frames vs. 26.9 > 20.5 frames, p=0.005). On multivariate analysis, only pre-adjuvant balloon CTFC was a predictor of a slower flow after adjuvant balloon inflation (odds ratio 1.148, 95% CI:1.014-1.301).

Adjuvant balloon inflation after successful primary stenting reduced residual stenosis but deteriorated the infarct artery flow. Further studies are required to define the clinical impact of the positive and negative effects of adjuvant balloon inflation.