Novel application of intravascular lithotripsy in stent under-expansion: A single-center experience

Introduction: Stent under-expansion due to calcification is associated with a less durable result. The development of intravascular lithotripsy (IVL) has provided clinicians with a readily available, simple-to-use treatment option for coronary calcification, but the use of IVL within a previously stented segment is currently off-license. There are, however, developing data suggesting that the use of IVL can be an effective treatment option for patients with calcific stent under-expansion.

Method: This was a single-center study of all patients treated with IVL for calcific stent under-expansion between January 2019 and June 2021. The impact of IVL on quantitative coronary angiography (QCA) stenosis and on the minimal stent area (MSA) derived from intracoronary imaging were recorded. The presence of periprocedural complications and adverse cardiovascular events was obtained from the clinical record during the study timeframe.

Results: Thirty-nine patients underwent IVL for calcific stent under-expansion during the study time frame with one patient treated with more than one lesion in the same session. In all lesions, there was an improvement in the QCA stenosis with 37 (92.5%) having a residual stenosis of ≤30%. The mean QCA stenosis pre-IVL was 68 ± 21% and following IVL the mean QCA was 18 ± 9% (p < 0.001). In all lesions, there was an improvement in the MSA, with 26 (92.9%) achieving an MSA of more than 4.5 mm² . The mean MSA pre-IVL was 3.88 ± 1.51 mm² and following IVL the mean MSA was 7.41 ± 2.34 mm² (p < 0.001). There were no major procedural complications. Over a mean follow-up of 506 ± 277 days, one patient died from ventricular arrhythmia but there were no other major adverse cardiovascular events.

Conclusion: This single-center study demonstrates that IVL is a safe and effective treatment for calcific stent under-expansion with good medium-term results.