rossing the lesion, initial dilatation by balloons and final stent expansion can present a challenge to the operator's skill and experience with heavily calcified lesions (HCL), because of the highly angulated lumen of these lesions and their resistance to expansion. 1,2 If balloons cannot cross or be expanded and the poorly steerable, thin, uncoated Rotablator ® wire (Boston Scientific, Natick, MA, USA) can be advanced, rotational atherectomy can result in favorable lesion modification that facilitates lesion dilatation and stent expansion. 3,4 Other methods of lesion preparation (eg, cutting balloon, high pressure pre-and post-dilatation) have been advocated for obtaining optimal stent expansion and apposition. Based on the examination of 3 representative cases with optical coherence tomography (OCT), we explain why optimal strut apposition remains an elusive target in the presence of heavy eccentric calcified plaques.
Case Reports
Case 1A 66-year-old male admitted with typical angina pectoris on a background of hypertension, hyperlipidemia and previous myocardial infarction underwent coronary angiography, which demonstrated long segments of heavily calcified severe stenoses in the mid left circumflex artery (Fig 1). The
Circulation Journal Vol.72, January 2008lesions were sequentially dilated with 1.5 and 2.0 mm noncompliant balloons up to 16 atm. Three sirolimus-eluting stents (SES, Cypher Select™, Cordis, Johnson and Johnson Co, Miami Lake, FL, US), 2.5×18, 3.0×13 and 3.0×23 mm, were implanted in an overlapping fashion and post-dilated with a non-compliant 3.0 mm balloon to 22 atm. Although the angiogram showed optimal lesion dilatation with only minimal lumen haziness (Fig 1C), OCT (LightLab Imaging Inc, Westford, MA, USA) revealed suboptimal stent expansion and poor stent strut apposition. 5 Despite multiple high-pressure dilatations, optimal circumferential expansion could not be achieved (Fig 2A). The irregular contours of the stent struts maintained a circular geometry and were unable to fully conform to the slit-like lumen induced by the severe calcification. Although circumferential expansion showed greater minimal lumen diameter compared with elliptic expansion (3.17×2.86 mm vs 3.33×1.97 mm), some struts still remained malapposed to the intima at the intimal tear between the superficial eccentric calcification and non-calcified intima (Fig 2). Although the stent expansion was acceptable, matching the distal reference lumen area, the irregularity of the lumen contours because of protruding eccentric calcification precluded strut apposition. We administered IIb/IIIa inhibitors and recommended long-term dual anti-platelet treatment. Follow-up at 4 months was uneventful.
Case 2A 71-year-old male admitted with angina pectoris on a background of hypertension, hyperlipidemia and previous myocardial infarction underwent coronary angiography, which demonstrated HCL in the mid right coronary artery. As no balloon could cross the stenosis, a Rotablator wire was inserted and a 1.5-mm burr was used, followed by ...