Cutting-balloon angioplasty before drug-eluting stent implantation for the treatment of severely calcified coronary lesions

BACKGROUND Severely calcified coronary lesions respond poorly to balloon angioplasty, resulting in incomplete and asymmetrical stent expansion. Therefore, adequate plaque modification prior to drug-eluting stent (DES) implantation is the key for calcified lesion treatment. This study was to evaluate the safety and efficacy of cutting balloon angioplasty for severely calcified coronary lesions. METHODS Ninety-two consecutive patients with severely calcified lesions (defined as calcium arc ≥ 180° calcium length ratio ≥ 0.5) treated with balloon dilatation before DES implantation were randomly divided into two groups based on the balloon type: 45 patients in the conventional balloon angioplasty (BA) group and 47 patients in the cutting balloon angioplasty (CB) group. Seven cases in BA group did not satisfactorily achieve dilatation and were transferred into the CB group. Intravascular ultrasound (IVUS) was performed before balloon dilatation and after stent implantation to obtain qualitative and quantitative lesion characteristics and evaluate the stent, including minimum lumen cross-sectional area (CSA), calcified arc and length, minimum stent CSA, stent apposition, stent symmetry, stent expansion, vessel dissection, and branch vessel jail. In-hospital, 1-month, and 6-month major adverse cardiac events (MACE) were reported. RESULTS There were no statistical differences in clinical characteristics between the two groups, including calcium arc (222.2° ± 22.2° vs. 235.0° ± 22.1°, P = 0.570), calcium length ratio (0.67 ± 0.06 vs. 0.77 ± 0.05, P = 0.130), and minimum lumen CSA before PCI (2.59 ± 0.08 mm(2) vs. 2.52 ± 0.08 mm(2), P = 0.550). After stent implantation, the final minimum stent CSA (6.26 ± 0.40 mm(2) vs. 5.03 ± 0.33 mm(2); P = 0.031) and acute lumen gain (3.74 ± 0.38 mm(2) vs. 2.44 ± 0.29 mm(2), P = 0.015) were significantly larger in the CB group than that of the BA group. There were not statistically differences in stent expansion, stent symmetry, incomplete stent apposition, vessel dissection and branch vessel jail between two groups. The 30-day and 6-month MACE rates were also not different. CONCLUSIONS Cutting balloon angioplasty before DES implantation in severely calcified lesions appears to be more efficacies including significantly larger final stent CSA and larger acute lumen gain, without increasing complications during operations and the MACE rate in 6-month.