Comparative impact of intravascular lithotripsy, rotational atherectomy, and orbital atherectomy on microvascular resistance and myocardial injury in complex coronary disease

Background Heavily Calcified coronary lesions are a challenge for advanced percutaneaous coronary interventions (PCI). While Rotational Atherectomy (RA), Orbital Atherectomy (OA) and Intravascular lithotripsy (IVL) are used to modify calcified plaques, their respective impact on microcirculatory function and periprocedural myocardial injury are not fully investigated. Purpose We aimed to compare the physiological and biological safety profiles of RA, OA and IVL. Methods From a monocentric prospective registry, we analyzed 60 consecutive patients (n=20 per group) undergoing PCI for severely calcified lesions using IVL (Shockwave), RA (Rotapro) or OA (Diamonback). Micovascular resistance (AMR) was measured pre- and post-procedure. Periprocedural myocardial injury was assessed by the variation of high-sensitivity troponin (ΔTropo). Statistical analysis for Δtroponin utilized the Kruskal-Wallis test for global comparison and the Dunn test for post-hoc pairwise comparisons due to non-normal distribution. Results Baseline clinical characteristics including age (72.8 ± 8.2 years), LVEF (56.8 ± 10.6 %), and lesion complexity (length >20 mm in 68.3 %), were well-balanced across the groups (p> 0.05). Procedural success (TIMI 3 flow) was achieved in 100% of cases. Significant micocircularoty impairement was observed in mechanical atherectomy groups, with marked increase in AMR for OA (+39.4%, p=0.008) an RA (+14.8 %, p=0.041) whereas AMR remained stable in the AVL group (+14.5 %, p=0.12). Regarding myocardial injury, a significant global difference was found between the three groups (p=0.024). Pairwise comparisons concluded that IVL was associated with significantly lower troponin elevation compared to RA (p=0.018) and OA (p=0.044). No significant difference was observed between OA and RA (p=0.58). Conclusion In patients with severely calcified lesions, IVL preserves microcirculatory function an minimizes periprocedural myocardial injyry more effectively than mechanical atherectomy. While both RA and OA significantly increase micovascular resistance, IVL demonstrates a superior safety profile, with significantly lower troponin release compared to both mechanical techniques.