Bail-out intravascular lithotripsy for severe stent underexpansion during primary angioplasty: a case report

BACKGROUND: Intravascular lithotripsy is safe and effective for the treatment of de novo coronary artery calcifications. Its bail-out use in acute coronary syndrome and for underexpanded stents, although currently off-label, could be the best option when other conventional techniques fail. CASE SUMMARY: A patient with an inferior ST-segment elevation myocardial infarction underwent a primary percutaneous coronary intervention. Stent underexpansion due to a heavily calcified lesion was refractory to high-pressure balloon dilatations. Complete stent expansion was achieved with intravascular lithotripsy, as evidenced by intravascular ultrasound, and no acute complications occurred. DISCUSSION: Treatment strategies for stent underexpansion due to coronary artery calcifications are still debated. High-pressure non-compliant balloon dilatations are rarely sufficient to gain a complete stent expansion. Rotational and orbital atherectomy are contraindicated in presence of a thrombus. Given the possible risks of stent damages, intravascular lithotripsy is currently not indicated in acutely deployed stents but could be the best bail-out technique for otherwise undilatable stents due to severely calcified plaques.