Preventive PCI of non-flow-limiting plaque was linked to benefit only when the plaque was lipid-rich

Design

Post hoc analysis of an open-label randomised trial

Population

598 patients with 632 non-flow-limiting high-risk lesions imaged with NIRS-IVUS

Primary outcome

Cardiac death, target-vessel MI, ischaemia-driven revascularisation or angina admission

Effect

Lipid-rich: 7.3% vs 17.6%, adjusted HR 0.23 (0.13 to 0.41); non-lipid-rich: HR 1.00 (0.54 to 1.86)

PREVENT randomised patients with non-flow-limiting but high-risk coronary plaques (FFR above 0.80) to preventive PCI or medical therapy. This post hoc analysis took the 598 patients who also had near-infrared spectroscopy, all with plaque burden above 70% and minimal lumen area below 4 mm² on intravascular ultrasound.

About 37% had a lipid-rich plaque by the prespecified threshold. Over a median 5.6 years, events were more frequent with lipid-rich plaque (12.5% vs 4.7%). Within that group, preventive PCI was associated with fewer events than medical therapy alone (7.3% vs 17.6%; adjusted HR 0.23, 95% CI 0.13 to 0.41). In plaques that were large and tight but not lipid-rich, there was no difference (adjusted HR 1.00).

This points to plaque composition, not just size, as the thing that might pick out lesions worth treating. But it is a post hoc subgroup in an open-label trial, the spectroscopy subset may not represent the whole trial, and the imaging is costly and not widely available.

• Do not change practice on this subgroup; preventive PCI of non-flow-limiting lesions is not standard care
• Large plaque burden alone did not predict benefit from stenting in this analysis
• Where intravascular imaging is used, lipid content may become part of the decision, pending a dedicated trial
• Intensive lipid lowering and antiplatelet therapy remain the treatment for non-flow-limiting plaque

Why it matters

It suggests the case for treating vulnerable plaque depends on what is inside it, not how big it looks.

Don't overread it

A post hoc subgroup of an open-label trial cannot establish that stenting lipid-rich plaque improves outcomes.

The statistics, in plain English

A hazard ratio of 0.23 would be a very large effect, which is one reason to be cautious: post hoc subgroups often overestimate. The significant interaction test strengthens the signal, but it remains hypothesis-generating.

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