What Is Provisional Stenting?

Provisional (conditional) stenting is a treatment philosophy that starts with one stent in a coronary bifurcation; it is not a fixed “one-stent technique” or a guarantee. The aim is to reconstruct the main vessel from proximal to distal across the side-branch opening, then match the proximal segment with proximal optimisation (POT). A second stent is added only if the side branch clearly needs it.^[1]

Parent overview: bifurcation and LMCA interventions.

What does a provisional approach mean?

The EBC 16th consensus treats it as a philosophy rather than a technique: one stent, the side-branch wire left in place (jailed wire), then systematic POT. Balloon diameter, pressure or a step-by-step operator list does not belong on a patient page.^[1]

In whom is it preferred?

Consensus recommends stepwise provisional for the vast majority of non-true non-left-main bifurcations and for true non-left-main lesions with side-branch lesion length under 10 mm. The 10 mm figure is a consensus boundary, not a validated cut-off that decides the case on its own. A one-stent approach may also be appropriate for true bifurcations with shorter side-branch lesions; EBC MAIN is cited in that frame.^[1]

Planned two-stent options are described on DK crush, culotte and, when needed, T-stenting.

What are the conceptual steps?

At patient level the sequence is:^[1,2]

1. Main-vessel stent: It covers the side-branch take-off (crossover). The side-branch wire may be left in place.
2. POT: The proximal main vessel is matched to its calibre with a balloon seated immediately proximal to the carina.
3. Rewiring the side branch: Consensus describes a distal crossing close to the carina as more favourable.
4. Balloon if needed: Opening the side branch or kissing inflation.
5. Second stent if needed: Options include T, TAP or culotte; no operator recipe is given here.

When is a second side-branch stent considered?

The EBC 18th consensus lists three conditions supporting side-branch stenting after main-vessel stenting: impaired TIMI flow; stenosis over 70% with angina and/or ECG changes; and extensive dissection greater than type B. The same table states the side branch should not be stented by default.^[2]

Trial protocols used related but non-identical thresholds. Nordic-Baltic IV used 75% residual ostial stenosis; DKCRUSH-VI used 70% in its angiography-guided arm. These numbers are not interchangeable universal rules and are not turned into patient instructions.^[2,4,5]

What does kissing balloon inflation do?

Nordic-Baltic III randomised 477 patients to final kissing or none after main-vessel stenting. Six-month major events were 2.1% versus 2.5%. At eight months side-branch restenosis was 7.9% versus 15.4% (p=0.039), and 7.6% versus 20.0% in true bifurcations. The angiographic side-branch result improved without a measurable short-term clinical difference. Angiographic restenosis is a surrogate. Kissing balloon inflation must not be said to reduce heart attack or death.^[6]

Can physiology show whether the side branch needs a stent?

DKCRUSH-VI randomised FFR-guided against angiography-guided provisional stenting. Side-branch stenting was attempted in 38.1% of the angiography arm versus 25.9% of the FFR arm; the 1-year composite was 18.1% in both. Fewer stents, the same clinical rate. A single trial of this size cannot exclude a modest difference. Physiology has not been shown to improve survival.^[5]

What are the limitations?

Crossover from provisional to a second stent varied widely: 3.7% in Nordic-Baltic IV, 28.6% in DKCRUSH-II, and 31% of provisional lesions in CACTUS. Anatomy and thresholds differ; these rates must not be averaged into a single “one-in-five rule”. The parent page’s approximately 20% figure is the EBC summary of randomised experience, not a separate pooled estimate.^[4,7,8]

Older trials (BBC ONE, Nordic I, CACTUS) predate contemporary drug-eluting stents and routine POT. Mixed-technique arms test a strategy, not a named technique.

Risks and emergency warnings

Provisional PCI carries the risks of stent treatment and coronary angiography. POT or kissing is not a survival promise. Call 112 for bleeding that will not stop, severe chest pain that does not settle, or impaired circulation in the access limb.^[9]

Assessment and decision

Provisional stenting is the starting plan for most bifurcations. The decision is renewed with the live side-branch result, imaging and centre experience. A second stent is part of stepwise treatment, not a failure label.^[1,2]