Last month at EuroPCR 2022, Dr Benjamin Honton, from Clinique Pasteur, Toulouse, presented the 1 year follow up pooled OCT analysis from Disrupt CAD III & IV studies, showing that consistent stent expansion and MSA post-IVL resulted in durable clinical outcomes, with no difference in event rates between concentric, eccentric and nodular calcium.
Discover what Dr. Honton thinks about the data and its impact in the treatment of calcified CAD patients in the Q&A below.
1. What does this 1-Year OCT Patient-level Pooled Analysis add to the interventional cardiology community?
The OCT Patient-level Pooled analysis brings meaningful insights into the midterm 12-month impact of OCT findings for patients treated by IVL. This pooled cohort of 160 patients from CAD III and CAD IV demonstrated a low rate of Target Lesion Failure (TLF) (6.9%) at one year with only one subacute stent thrombosis despite complex coronary lesions included in these studies. Moreover, this rate is essentially driven by periprocedural MI with a low rate of events in the follow-up. Interestingly, the OCT independent core-lab analysis showed that the only factor associated with TLF in OCT baseline was a higher maximum calcium arc (328° +/- 48 vs 273° +/- 80; p = 0.03). However, none of the post-stent OCT findings were correlated to the occurrence of TLF, especially those known as strong predictors of cardiovascular events like MSA, maximum stent expansion, or strut malapposition. Moreover, these OCT analyses show that IVL is safe and effective across all types of calcified pattern lesions like eccentric lesions or calcified nodules.
2. From your perspective, what did we learn about the long-term clinical outcomes in calcified nodules and eccentric lesions treated with coronary IVL?
Initially, IVL was studied to target concentric calcified lesions. However, this OCT Patient-level Pooled analysis demonstrates that CAD III and CAD IV studies included patients with eccentric lesions (Calcium Arc <180°; n =30) or calcified nodules (CN; n = 26). These features, particularly CN, remain a significant challenge in our daily practice, often complex to treat with a worst outcome. The OCT Patient-level Pooled analysis brings confidence for IVL in this setting as there is no difference in 12-month TLF in patients treated for a CN or an eccentric calcified lesion than the others. Moreover, post-OCT findings show a mean MSA of 6.2 +/- 2 mm2 with a stent expansion of 101 +/- 18% in the CNs groups confirming the effectiveness of IVL for the management of such complex lesions.
3. How do these outcomes compare with previous reports on the use of rotational atherectomy to treat calcified nodules?
It is always hazardous to compare results from previous studies. However, we can affirm that the rate of complications with IVL for this kind of lesion is drastically low. Moreover, we know that the CNs are more prone to set in the tortuosity of the right coronary artery making the realization of rotational atherectomy (RA) more complex, with a higher risk of complications and a potential guide wire bias impairing RA lesion preparation. In this view, IVL appears to be safer, and the OCT Patient-level Pooled analysis brings clinical evidence that it is also effective. In this perspective, IVL opens new perspectives and should be considered a first-line therapy to prepare CN lesions before stenting.
4. What would you say to your peers who don’t use concomitantly intracoronary imaging with IVL to treat calcified lesions. Do you think that intracoronary imaging is mandatory in a real-world setting in order to attain good results with IVL?
Intracoronary imaging gives meaningful information on calcification patterns ignored by angiography, as calcium angle which is associated with higher TLF in the OCT pool analysis. There is a significant world wild heterogeneity in intracoronary imaging use for multiple reasons. The OCT Patient-level Pooled analysis gives confidence that IVL effectively treats all types of calcium with no procedural adjustment needed for that purpose. In this setting, intravascular imaging could not be mandatory "per se" but remains a valuable tool for planning our PCI strategy with IVL and appreciating stent failure patterns such as malapposition or underexpansion more frequently in the calcified lesion. In this view, intracoronary imagery is expected to increase over time and should be promoted.
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