Successful calcium modification of a large calcified nodule using shockwave intravascular lithotripsy in the setting of acute coronary syndrome: a case report.

Background: Calcified nodules are associated with suboptimal preparation before stenting due to challenging crossing and unsuccessful pre-dilation and calcium cracking with conventional balloons. In this scenario, we report the use of shockwave intravascular lithotripsy for the successful lesion preparation of an undilatable and challenging calcified nodule in a patient presenting with ACS.

Case summary: We report a case of a 79-year-old male patient presented with non-ST elevation myocardial infarction. Coronary angiography revealed 90% stenosis in the proximal segment of the right coronary artery, with a hazy area of inhomogeneous contrast. Intravascular ultrasound (IVUS) imaging identified a large eccentric calcified nodule, with a minimum luminal area (MLA) of 4.18 mm². Rotablation was done with a ROTAPRO Atherectomy System, post-rotablation IVUS showed no plaque modification. Intravascular lithotripsy (IVL) was performed with the emission of 50 pulses. Post-IVL, IVUS showed that the calcium nodule was successfully cracked with increased MLA to 6.8 mm². The lesion was pre-dilated with a cutting balloon and stented using a SYNERGY MEGATRON stent and post-dilated with a non-compliant balloon with good final angiographic result and TIMI Grade 3 flow. Post-stenting IVUS confirmed optimal stent apposition and expansion with an MLA of 11.9 mm².

Discussion: In severely calcified lesions, like calcified nodules, lesion preparation before stenting is pivotal for optimal long-term outcomes. As demonstrated in this case, IVL can be used safely in the setting of ACS not only to treat superficial and deep calcium layers but also to crack a large, calcified nodule, after failure of rotablation.