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.