The effect of postdilatation on coronary blood flow and inhospital mortality after stent implantation in st-segment elevation myocardial infarction patients

Abstract

Background: Adjunctive balloon postdilatation is often performed after stent deployment to improve stent expansion during percutaneous coronary intervention (PCI). However, aggressive mechanical expansion may increase distal thromboembolization and microvascular injury, especially for patients with ST-segment elevation myocardial infarction (STEMI). Therefore, the benefit of postdilatation in these patients remains controversial. We aimed to investigate the effects of postdilation on coronary blood flow and inhospital mortality. Materials and Methods: A retrospective analysis was made of patients who received primary PCI because of STEMI. A total of 216 patients were included, as 108 applied with postdilatation following stent implantation and 108 not applied with postdilatation using propensity score matching method. Coronary blood flow was evaluated using the thrombolysis in myocardial infarction (TIMI) flow and myocardial blush grade (MBG). Results: The baseline clinical, angiographic, and laboratory characteristics of the groups were similar (P > 0.05). No-reflow developed in 34 (15.7%) of all patients according to TIMI flow (0–2), and in 36 (16.6%) according to MBG (0–1). While the no-reflow (TIMI 0–2) rates of the groups at baseline and following stent implantation were similar (94.4% vs. 95.4%, P = 0.757 and 23.1% vs. 20.4%, P = 0.621), the final no-reflow (TIMI 0–2) rate was significantly higher in the postdilatation group (22.2% vs. 9.3%, P = 0.009). Inhospital mortality rate was determined to be higher in the postdilatation group, but it was statistically nonsignificant (8.3% vs. 5.6%, P = 0.422). Conclusion: The application of postdilatation during primary PCI increased the development of no-reflow phenomenon in STEMI patients.