Side Branch Additional Treatment for Coronary Bifurcation Lesion Revascularization: Insights From the KISS Randomized Trial.

Summary

In 616 patients with non-left main bifurcations, a no–systematic side-branch strategy was noninferior to routine SB intervention for periprocedural MI/injury and reduced procedure time, radiation, and contrast. Bail-out SB treatment was rarely needed (2%), with similar 12-month target lesion failure and fewer SB dissections versus systematic SB intervention.

Key Findings

• No-SBI strategy was noninferior for periprocedural MI/injury (4.1% vs 5.7%; P<0.001 for noninferiority).
• Bail-out SB intervention was required in only 2.0% of no-SBI patients.
• Procedure time, radiation dose, and contrast volume were significantly lower without routine SBI.
• SB dissection occurred more often with SBI (2.9% vs 0.0%; P=0.004).
• 12-month target lesion failure was similar (4.9% vs 6.4%; P=0.442).

Clinical Implications

For most non-left main bifurcations, default main-branch-only stenting with proximal optimization can minimize procedural risk and resource use without compromising outcomes; reserve SB treatment for flow impairment or bail-out needs.

Limitations

• Excludes left main bifurcations; generalizability to complex anatomies may be limited.
• Single stent platform used; longer-term outcomes beyond 12 months not primary.

Future Directions

Pragmatic trials in left main and complex bifurcations, cost-effectiveness analyses, and physiology-guided criteria to trigger selective SB optimization.