Objective To investigate the effects of staccato reperfusion (SR) during percutaneous coronary intervention (PCI) on myocardial microcirculatory function as assessed by myocardial contrast echocardiography.

Setting Tertiary centre.

Methods Thirty-nine patients were randomised to SR (n=20) or abrupt reperfusion (AR, n=19) within 48 h of an acute coronary syndrome. Contrast intensity replenishment curves were constructed to assess the blood volume (An), velocity (β) and flow (A×β) of the segments associated with the PCI-treated artery before, 48 h, 1 and 12 months after PCI. Left ventricular (LV) end-diastolic (EDVs) and systolic volumes (ESVs) were evaluated. Plasma malondialdehyde (MDA) was determined immediately before and 18 min after PCI to assess oxidative stress.

Results SR was related to a greater improvement in A_n, β and A×β at 48 h, 1 and 12 months after intervention compared with AR (mean A×β: 0.91, 5.5, 7.14, 6.9 for SR vs 1.02, 3.34, 4.28, 3.71 for AR, p<0.01). After PCI, the mean MDA change was −27% in SR patients and +55% in the AR patients (p<0.05). The percentage change in MDA correlated with the percentage change in A_n at all time points (r=0.468, r=0.682, r=0.674, p<0.01). Compared with AR, SR was related to a greater percentage decrease in EDV (−11.61% vs −4.13%) and ESV (−34.68% vs −14.83%) at 12 months after PCI (p<0.05). The percentage change in ESV at 12 months correlated with the corresponding percentage changes in A_n, β and A×β (r=−0.410, r=−0.509, r=−0.577, respectively, p<0.05).

Conclusions SR improves myocardial microcirculatory function after PCI, leading to a concomitant improvement in LV geometry, probably through reduction of oxidative stress.