Stent underexpansion due to calcifications is a predictor of stent failure and adverse clinical outcomes. Intravasular lithotripsy (IVL) has proved to be effective in dilating calcified de novo coronary lesions, but indications for the technique are expanding.
A 56-year-old man was scheduled for percutaneous coronary intervention due to severely calcified in-stent restenosis (ISR) in a bifurcation dedicated drug-eluting stent (DES) BiossLimC 3.5/4.25/24 mm which had been implanted 2 years prior into the left main/left anterior descending artery (LM/LAD) with a suboptimal result (residual stenosis of 50% in the proxLAD due to calcificatitons). As confimed during the present admission, the lesion progressed (90% calcified ISR) (Fig. 1A) and was unsuccessfully dilated with non-compliant balloon (NCB) inflations (Fig. 1B). Advancement of intavascular ultrasound catheter to interrogate the lesion was unsuccessful. Considering the presence of severe calcifications, calcium deposits covered by the previously implanted stent and angiographically visible calcifications in the outer layers of the vessel, we elected to use IVL. IVL balloon (Shockwave 3.5/12 mm) was positioned and inflated within the lesion in the proxLAD (4 atm).Then, 80 shockwave pulses were delivered with a subsequent pressure increase (6 atm). The “dog--boning“ effect (Fig. 1B) which had been observed during NCB inflations dissapeared (Fig. 1C) and the lesion was re-dilated with NCBs (NC Emerge 3.5/12 mm, Pantera Leo 3.75/12 mm). Subsequently, DES (Orsiro 3.5/13 mm) was implanted (Fig. 1D) and post-dilated with a NCB (Pantera Leo 3.75/ /12 mm). A satisfactory angiographic result was achieved (Fig. 1E) with good expansion/apposition of the stent, and achievement of Kang’s criteria (Fig. 1F).
The present case implies that IVL is an effective modality for undilatable ISR caused by stent underexpansion secondary to calcifications.
