Coronary laser with simultaneous contrast injection for the treatment of stent underexpansion.

Background: Stent underexpansion is a challenge in interventional cardiology. Some off-label treatments, such as rotational atherectomy, intravascular lithotripsy (IVL) and coronary lasing, have been used to overcome the problem. The purpose of this study is to evaluate the safety and efficacy of coronary laser atherectomy with simultaneous contrast injection and subsequent balloon dilation to optimize stent expansion.

Methods: Coronary laser atherectomy with simultaneous contrast injection was used. After lasing, non-compliant balloon dilation at high pressure was performed to overcome the underexpanded point. The average increase in the minimum stent area (MSA) was measured by intravascular ultrasound (IVUS), and any complication related to the technique was evaluated. Additionally, major adverse cardiovascular events (MACE), consisting of death from any cause, new myocardial infarction (MI) and target lesion revascularization (TLR), were scrutinized in a long-term follow-up.

Results: Sixteen underexpanded stents were treated with laser between August 2017 and November 2022. In all cases but one, IVUS was used to evaluate the MSA before and after lasing. The MSA showed an average increase of 2.34 ± 1.57 mm² (95% confidence interval [CI]: 1.47-3.21; p < 0.001) after laser application and balloon inflation. No complication related to the technique was detected. During a follow-up period of a median (interquartile range) of 457 (50-973) days, the combined MACE assessed by Kaplan-Meier estimator showed an event-free rate of 0.82 (95% CI: 0.59-1).

Conclusions: Coronary laser with simultaneous contrast injection is a safe method to optimize a stent underexpansion, with an acceptable event-free rate in long-term follow-up.