Improved stent expansion with prolonged compared with short balloon inflation: A meta-analysis

Despite evidence from individual studies suggesting that prolonged inflation improves coronary stent expansion, relatively shorter inflation times are commonly employed in clinical practice.

We performed an electronic search of PubMed, Web of Science, Cochrane, and CINAHL databases to retrieve outcome studies comparing prolonged versus short inflation times during stent deployment. Outcomes studied included minimal stent diameter (MSD) and minimal stent area (MSA). Standardized mean difference (SMD) was used to estimate the effect sizes for these continuous variables.

Seven studies with a total of 341 patients (415 lesions; mean age 67.6 years; 82% male) were included. Drug-eluting stents were used in 89 ± 15% of coronary lesions. Prolonged stent inflation was associated with increased minimal stent diameter (2.93 ± 0.34 mm vs. 2.72 ± 0.28 mm; SMD = 0.42; 95% CI 0.25-0.59; P < 0.001) and minimal stent area (5.99 ± 1.21 mm² vs. 5.17 ± 0.87 mm² ; SMD = 0.46; 95% CI 0.19-0.73; P = 0.001) compared with shorter duration stent inflation. This difference remained significant in sensitivity analyses that excluded studies with very prolonged inflation duration or multiple stent balloon inflations.

Despite differences in duration and methodology, prolonged stent inflation is associated with improved expansion compared with shorter duration. The effect of this optimization recommends randomized trials to determine whether long-term outcomes can be improved by this simple technical modification.