Dual antiplatelet therapy duration determines outcome after 2- but not 1-stent strategy in left main bifurcation percutaneous coronary intervention

Selected in JACC Cardiovascular Interventions by E.W. Holy , S. Brugaletta

This joint review is part of the PCRonline GLOBAL Journal Club Initiative by selected members of the EAPCI/PCR Journal Club and PCR NextGen, and is based on the underlying idea of “Bringing peers together, exchanging ideas, towards a common standard of care”.

Reviewers

Erik Walter Holy

Interventional cardiologist / Cardiologist

Andreas Grüntzig Catheterization Laboratories, University Heart Center Zurich -

Salvatore Brugaletta

@sbrugaletta

Interventional cardiologist / Cardiologist

Barcelona, Spain

Our Comment

Why this study – the rationale/objective?

Despite the recent advances made in the field of PCI techniques and coronary stent technologies, the treatment of distal left main (LM) bifurcation lesions remains challenging. In particular, the choice of the optimal PCI strategy (1- or 2-stent), as well as duration of dual antiplatelet therapy (DAPT) depending on the chosen strategy, is still debated. The current analysis investigates the clinical outcomes after LM bifurcation PCI using 1 or 2 new generation drug-eluting stents and the impact of DAPT duration.

How was it executed – the methodology?

Data from 5 different multicenter observational studies conducted in Korea were pooled in the Grand DES Registry analysis. 13,172 patients who were treated with new-generation DES were subject for analysis. Following exclusion of patients without bifurcation lesions or with non-LM lesions, 700 patients with LM bifurcation lesions remained as the final study population.

• Primary outcomes: target lesion failure (TLF) and thrombotic adverse cardiovascular events (TACE) including cardiac death, all-cause MI, and stent thrombosis (ST).
• Secondary outcomes: individual clinical outcomes including the components of composite outcomes.
• Clinical follow-up was performed at 1, 3, 9, and 12 months and then annually up to 3 years.
• Choice of PCI strategy (1 stent or 2 stents) and duration of DAPT (aspirin+clopidogrel) were left to the operators’ discretion.

What is the main result?

• Out of the 700 patients treated for LM bifurcation lesions, 567 were treated with a 1-stent strategy and 133 with a 2-stent strategy.
• Rates of TLF were higher in the 2-stent group, while risks for TACE and its components were comparable between the 2 strategies.
• Risks for TLF and TACE in the 2-stent group were significantly higher in patients with DAPT interruption <1 year, while they were similar in those receiving DAPT maintenance for at least 1 year.

Critical reading and the relevance for clinical practice

The present study adds further evidence on the role of PCI complexity in addition to patient related characteristics as an independent ischemic risk factor guiding optimal duration of DAPT in LM bifurcation stenting. While use of a 2-stent strategy for treatment of LM bifurcations with new generation DES resulted in similar clinical outcomes in terms of hard endpoints compared to a single stent strategy up to 3 years after the index procedure, a higher rate of TLF was observed in the 2-stent group when associated with DAPT discontinuation < 1 year. Authors said that prolonged DAPT may be necessary when considering a 2-stent strategy in LM bifurcation PCI.

The observational study design does not allow unfortunately a real evaluation of DAPT duration based on an intention-to-treat analysis. This finding is indeed a result of a multiple subgroup analysis, which significantly reduces its statistical and clinical value. Furthermore, details on the reasons for DAPT discontinuation < 1 year as well as on lesion complexity are not fully explored, so that it is hard to know if it is the real cause of the event or conversely a consequence of an event. It cannot be also excluded that patients undergoing complex PCI with a 2-stent strategy may have a more extensive coronary artery disease and are therefore more prone to TLF upon earlier DAPT interruption.

Which DAPT duration do you usually prescribe in your left main PCI with 1- or 2-stent?