IVUS Guidance In Complex High-Risk PCI Fails To Lower TVF

Key Takeaways

• Target-vessel failure occurred more often numerically with IVUS guidance, and a lower primary-endpoint risk was not reported with that strategy.
• IVUS-guided procedures lasted longer and more often included balloon angioplasty after stent implantation.
• Procedural complication frequencies were similar between groups, and follow-up extended to a median of 19.0 months.

In the IVUS-CHIP randomized trial, routine IVUS-guided PCI with prespecified stent-optimization criteria was not associated with lower target-vessel failure risk than angiography-guided PCI alone among patients undergoing complex high-risk PCI, with a hazard ratio of 1.25.

The study was an investigator-initiated, international, open-label randomized controlled trial in patients undergoing complex PCI. Patients were assigned to IVUS-guided PCI with prespecified stent-optimization criteria or angiography-guided PCI alone. For the primary analysis, 1010 patients were in the IVUS-guided group and 1009 were in the angiography-guided group. Mean age was 69 years, 79.4% were men, 27.4% presented with acute coronary syndrome, and the prespecified primary endpoint was target-vessel failure, defined as cardiac death, target-vessel myocardial infarction, or clinically indicated target-vessel revascularization. The trial was identified as IVUS-CHIP, with median follow-up of 19.0 months and an interquartile range of 15.2 to 23.4 months.

Procedural measures differed between the two strategies in the primary comparison. Mean procedure duration was 88.8 minutes with IVUS guidance and 66.2 minutes with angiography guidance. Balloon angioplasty after stent implantation was performed in 91.3% of IVUS-guided procedures and 84.5% of angiography-guided procedures. Procedural complications occurred in 11.3% and 10.2% of procedures, respectively. The more imaging-intensive strategy was accompanied by longer procedures and more post-stent balloon use, while complication frequencies were similar between groups.

At median follow-up, the target-vessel failure comparison showed events in 13.9% of the IVUS-guided group and 11.1% of the angiography-guided group. The reported effect estimate was a hazard ratio of 1.25 with a 95% confidence interval of 0.97 to 1.60. The reported P value was 0.08. The investigators concluded that routine IVUS-guided PCI was not associated with a lower risk of target-vessel failure than angiography-guided PCI alone. That comparison was the central finding of the randomized trial.