Intracoronary ultrasound-guided angioplasty for coronary chronic total occlusion.

Background: Recanalisation for coronary chronic total occlusion (CTO) is associated with high rates of restenosis and reocclusion. The use of intracoronary ultrasound (ICUS) may improve immediate and long-term outcomes following recanalisation. To our knowledge, no study has examined the use of ICUS-guided balloon angioplasty in CTO.

Aim: To compare the results of ICUS-guided balloon angioplasty and ICUS-guided angioplasty with stent implantation in patients with CTO.

Methods: The study involved 51 CTO patients in whom optimal balloon angioplasty results were achieved according to quantitative coronary angiography (QCA). These patients then underwent ICUS-guided balloon angioplasty with the goal of achieving a minimal luminal cross-sectional area (MLCSA) of > 6.0 mm2 and a residual plaque burden (RPB) of < 65%. Of the 51 patients, the ICUS criteria defining optimal balloon angioplasty were achieved in 23 patients and 7 patients did not undergo stent implantation due to calcification and/or small vessel diameters (group A--30 patients). In 21 patients, the failure to achieve optimal ICUS parameters resulted in stent implantation with the goal of achieving in stent MLCSA > 9 mm2 and > 55% of average total cross-sectional area of the vessel according to distal and proximal reference segments (group B). The two groups were similar in terms of clinical and angiographic characteristics.

Results: Balloon angioplasty which was regarded as optimal by QCA, was shown to be non-optimal by ICUS in 41 patients (80.4%). The MLCSA was smaller in group A than group B (6.5 +/- 1.5 vs. 8.9 +/- 2.0 mm2; p < 0.001). Restenosis was found in 8 (26.6%) group A patients and 4 group B patients (19%) (p > 0.05). The restenosis rate in 23 group A patients with optimal ICUS parameters was 8.6% (2 patients). Consecutive ICUS measurements showed a gradual increase in the total vessel area during the PCI procedure and at the 6-month follow-up (p < 0.05).

Conclusions: (1) Achieving an optimal balloon angioplasty result in CTO patients requires confirmation using ICUS. (2) In some patients immediate and long-term outcomes following ICUS-guided optimised balloon angioplasty are comparable to those of ICUS-guided stent implantation. (3) Direct measurement of a chronically occluded coronary artery at pre-intervention, during the intervention and at long-term follow-up may argue in favour of using ICUS in recanalisation of CTO. (4) ICUS-guided balloon angioplasty for CTO could be a method of choice in patients in whom long-term dual antiplatelet therapy is associated with a high probability of bleeding complications.