Evaluation of the Intravascular Ultrasound Calcium Scoring System in Guiding Intravascular Lithotripsy During Percutaneous Coronary Intervention.

Background: In Japan, intravascular lithotripsy (IVL) is indicated during percutaneous coronary intervention (PCI) for calcified lesions when the calcium score assessed by intravascular ultrasound (IVUS) or optical coherence tomography (OCT) is ≥3. This study evaluated the effectiveness of IVL in achieving optimal stent expansion in lesions with an OCT calcium score ≥3, regardless of the IVUS calcium score.

Methods and results: We retrospectively compared 26 consecutive PCIs in 23 patients who underwent IVL with pre-PCI OCT or optical frequency domain imaging and simultaneous pre- and post-PCI IVUS with 102 patients who underwent PCI without atherectomy but similar imaging protocols. Of all 128 PCIs, 84 with an OCT calcium score ≥3 and a simultaneous IVUS calcium score ≤2 were analyzed. Stent expansion was measured by IVUS. Among the 84 PCIs included in the analysis, 17 were performed using IVL and 67 were performed without atherectomy or IVL (non-IVL group). Stent expansion at the site of maximum superficial calcium was greater in the IVL than non-IVL group (90.9% vs. 84.6%, respectively; P=0.028). The non-IVL group was independently associated with reduced stent expansion at the site of maximum superficial calcium, even after adjusting for IVUS calcium score components (B=-0.817; P<0.001).

Conclusions: Even in calcified lesions with an IVUS calcium score ≤2, IVL was independently associated with favorable stent expansion when the OCT calcium score was ≥3.