Assessment of safety, efficacy and learning curve of intravascular lithotripsy in real world practice within a high volume calcium modification centre
Authors: Hinton J , Din J , Kodoth V , Levy T , Swallow R , Talwar S , O'kane P 
Published: October 2024

Abstract

Background
There has been a rapid uptake in the use of intravascular lithotripsy (IVL) for calcium modification during percutaneous coronary intervention (PCI) due to its ease of use and excellent safety profile, particularly when compared to atherectomy devices.

Purpose
To review the adoption and safety of IVL in a high volume centre with established use of alternative calcium modification techniques

Methods
This was a retrospective analysis of all patients undergoing PCI from the introduction of IVL in January 2019 until December 2023. Patient demographics, comorbidity, procedure details and procedural complications were compared between IVL and non-IVL cases. Line charts were created to demonstrate the uptake and use of IVL per quarter compared with other established calcium modification strategies. A further line chart was created to compare the frequency of IVL use per quarter in more complex cases (left main intervention, ST elevation, treatment of in stent restenosis and in combination with rotational/orbital atherectomy).

Results
In the analysis timeframe there were 7,843 PCI cases performed, of which there were 301 IVL cases, 263 rotational/orbital atherectomy cases and 77 excimer laser atherectomy. IVL cases were older, more likely to have previous revascularisation (PCI (40.8% vs 57.1 % (p&lt;0.001)) or bypass grafts 4.8% vs 8.0% (p=0.012)), diabetes mellitus (22.7% vs 33.6% (p&lt;0.001)) and hypertension (45.4% vs 56.5% (p&lt;0.001)). From a procedural perspective, treatment of left main and restenosis were more common with IVL compared with the rest of the cohort (7.0% vs 27.6% (p&lt;0.001) and 8.3% vs 28.9% (p&lt;0.001) respectively). IVL cases were more frequently guided by intracoronary imaging (intravascular ultrasound 35.9% vs 70.4% (p&lt;0.001), optical coherence tomography 3.7% vs 18.9% (p&lt;0.001)). Atherectomy was more frequent in IVL cases (excimer laser atherectomy 0.7% vs 7.3% (p&lt;0.001) and rotational/orbital atherectomy 2.6% vs 22.9% (p&lt;0.001)). Figure 1 shows the frequency of IVL use compared with other established calcium modification strategies per quarter and demonstrates the rapid and sustained uptake in IVL usage. Interestingly the use of other atherectomy techniques does not appear to have reduced. Figure 2 shows that IVL was quickly utilised in more complex calcification cases and again this has remained consistent since the introduction. Both figures demonstrate the short learning curve associated with IVL. Finally, there was no significant increase in perforation or slow/no reflow with IVL use (0.5% vs 0.7% (p=0.647) and 1.1% vs 1.3% (p=0.675) respectively) consistent with the published literature. There was an increase in documented coronary dissection with uncertain impact (3.4% vs 6.5% p=0.017).

Conclusions
IVL has become an essential tool within the calcium modification algorithm as a result of its ease of use, efficacy and excellent safety profile.Calcium modification per quarterFrequency of complex IVL cases