Combined Orbital and Rotational Atherectomy for Severe Nodular Calcification at Curved Arteries

An 81-year-old woman with aplastic anemia, severe chronic kidney disease, pacemaker for sick sinus syndrome, and chronic heart failure secondary to severe atrial functional mitral regurgitation presented with progressive exertional angina. Coronary angiography and electrocardiography-gated non-contrast computed tomography showed calcified stenosis with severe nodular calcification (NC) in the mid-right coronary artery (Figure A–C). Intravascular ultrasound (IVUS) showed eccentric calcification with nonuniform rotational distortion (Figure D-i,E-i). Rotational atherectomy (RA) was unfeasible because of coronary perforation risk at the outer curvature, but the morphological NC characteristics at the inner curvature were suitable for low-speed orbital atherectomy (OA). After 2.0-mm semi-compliant balloon angioplasty, the OA-crown was successfully delivered (Figure D-ii,E-ii). IVUS after 12 pullback low-speed OA confirmed appropriate and safe NC debulking, supporting additional high-speed OA (Figure D-iii,E-iii). After 10 pullback high-speed OAs, IVUS showed further effective NC debulking and preferable wire bias for RA; however, a partial deep-cut of the media was found at the distal lesion (Figure D-iv,E-iv). Thereafter, RA with a 1.75-mm burr (180,000 rpm) was performed using the halfway technique, while avoiding coronary perforation (Figure D-v,E-v). Balloon angioplasty with a 2.75/13-mm scoring balloon and 2.75/30-mm drug-coated balloon was performed with acceptable results while considering possible additional NC debulking in the future (Figure E-vi,F). The patient had an uneventful outcome.

Figure.

(A) Initial and (F) final coronary angiography images (B,C) Electrocardiography-gated non-contrast computed tomography (CT). Arrowheads show nodular calcification (NC). (D) Schematic showing the debulking strategy for NC at the inner artery curvature. (E) Intravascular ultrasound imaging of each step. Asterisk, extravascular structures; arrowheads, nodular calcification; arrow, deep-cut of the media. OA, orbital atherectomy; POBA, plain old balloon angioplasty.

Debulking with RA alone for severe NC in curved arteries has the risk of coronary injury due to the unfavorable wire bias at the outer curvature. This case of NC at the inner curvature suggested that pullback OA could move the wire more centrally, providing favorable wire positions for safe RA. Moreover, careful lumen evaluation with intracoronary images guided the RA using the halfway technique, preventing further coronary injuries distal to the NC where the wire bias was pointed to the outer curvature. When the OA-crown smoothly reaches distally, staged debulking with pullback OA followed by RA may be useful for severe NC of the inner curvature.

Acknowledgments

None.