Comparison of Double Kissing Culotte Stenting With Double Kissing Crush Stenting for True Bifurcation Lesions
Condition: Coronary Heart Disease
MeSH terms: Heart Diseases; Coronary Disease; Coronary Artery Disease; Myocardial Ischemia
Study type: Interventional

Summary: 
      Percutaneous coronary intervention (PCI) for the treatment of coronary bifurcation lesion
      (BL) remains a challenging task. The DK-crush have been established as a safe and efficacious
      dual-stenting technique, which can effectively improve the success rate of final kissing
      balloon inflation (FKBI) and reduce long-term major adverse cardiac events (MACE). However,
      in the clinical real world, especially when the bifurcation angle was relatively small, the
      DK-crush still has several limitations, such as kissing unsatisfied (KUS), relatively complex
      wiring or rewiring technique, incomplete stent coverage in the distal side of the side-branch
      ostium and near the carina, severe stent deformation or evenly acute stent destruction. Our
      observational study showed that the DK-culotte was also a safe and feasible dual-stenting
      technique and was equal to DK-crush in terms of improving FKBI and MACE. Nonetheless, there
      remain no studies for head-to-head comparison of clinical outcomes between the two
      approaches. We, thereby, carry out a multicentre, non-inferior, randomized and controlled
      trial to compare DK-culotte stenting versus DK-crush stenting in the treatment of true BL.
    

Detailed description: 
      How to properly treat coronary bifurcation lesion (BL) is still controversial in the field of
      percutaneous coronary intervention (PCI). The current guidelines recommended simpler
      strategies, single crossover stenting or provisional stenting, as the preferred treatment.
      However, the acute occlusion or loss of important branches, which affects immediate as well
      as long-term outcomes, may result from such simpler strategies as treating severe true
      bifurcation lesion (TBL). Therefore, for the procedural safety, double stenting is clinically
      necessary particularly in treatment of major vessel bifurcation lesions.

      Up to date, a great number of double-stenting techniques have been introduced clinically:
      crush stenting (classic crush, mini-crush, step-crush, DK-crush), culotte stenting (classic
      or modified culotte stenting), T-stenting (classic or modified T), and V-stenting (step
      V-stenting, simultaneous kissing stenting). Of which, crush-based and culotte-based stenting
      have been the most popular techniques.

      The DK-crush has been demonstrated as a safe and efficient procedure, which can effectively
      elevate the success rate of final kissing balloon inflation (FKBI) and reduce long-term major
      adverse cardiac events (MACE). However, in the clinical real world, especially when the
      bifurcation angle was relative small or parallel, the DK-crush still has several limitations:
      (1) although initial kissing balloon inflation (IKBI) can push away the struts covering the
      side-branch ostium and remold the geometric shape of orifice, redundant struts will be
      crushed aside onto parent-vessel wall and the side-branch ostium, thereby inducing turbulent
      flow due to local unsmooth vessel lumen; (2) once the main-vessel stent was released, the
      side-branch orifice will be squeezed crushed again, thus resulting in stent deformation,
      malapposition or incomplete coverage near the bifurcation arena and carina; (3) because of
      deformation or crush of the side-branch stent at its ostium, rewiring the side-branch may be
      extremely hard with subsequent balloon passing difficulty, leading to low quality or failure
      of FKBI, or sometimes stent destruction as the wire runs out of the stent.

      Culotte-based stenting has been demonstrated superior to crush-based stenting in reduction of
      the side-branch restenosis though overall MACE is similar in Nordic studies [PMID: 20031690].
      However, it is an essential requirement of similar size of the two branches when using the
      conventional culotte stenting. As firstly described by us, the modified culotte stenting
      [PMID: 22088451], to start with stenting the side-branch (smaller branch) and by
      pre-imbedding a balloon in the main-branch for prevention of acute branch loss, has no strict
      requirement of similar size of the two branches and has been proven to be a safe and
      efficient procedure for treatment of TBL. However, if the diameter difference between two
      branches is too much (>0.75 mm), a circular under-expansion band (CUEB) of main-branch stent
      in the parent vessel near the bifurcation arena will frequently occurred since the
      side-branch stent implanted earlier will limit the expansion of the main-branch stent
      implanted subsequently by its side-hole and the portion protruding into the parent vessel,
      leading to local stent malapposition and the risk of in-stent thrombosis. For overcome CUEB,
      we further improved culotte-based stenting to order to develop a novel culotte stenting, the
      DK-mini-culotte stenting, by the following modifications: (1) pre-imbedding a balloon in the
      main-branch for prevention of acute vessel loss, (2) firstly stenting the smaller side-branch
      with shorter protrusion (mini-protrusion) of the stent into the parent vessel, (3) performing
      IKBI prior to the main-branch stenting for fully expanding the side-hole and protruded
      portion of the side-branch stent, (4) finally stenting main-branch after IKBI, followed by
      FKBI.

      Our series studies, including mimic stenting in artificial vessel in vitro, hemodynamics and
      flow-field investigations in vitro or in vivo, and pilot clinical observation, have
      demonstrated that the DK-mini-culotte stenting is necessary for the achievement of
      high-quality hemodynamic and morphological results, and is superior to the crush-based
      techniques for treating TBL.

      Particularly, our initial clinical experience has shown the DK-mini-culotte stenting has
      several advantages: (1) efficiently eliminating CUEB and preventing stent malapposition by
      IKBI;(2) technically easier to be performed, particularly for wiring/rewiring and for balloon
      passing during IKBI and FKBI; (3) technically safer to complete the procedure, especially for
      preventing the acute vessel occlusion or loss; (4) effectively preventing the deformation and
      collapse that occasionally happened when using the crush-based stenting; (5) mostly close to
      the general technique for treating BL regardless of size difference of branches and
      bifurcation angle; (6) potentially long-term benefits because of complete and even stent
      coverage in the treated segments particularly in the bifurcation arena and carina. However,
      there remains no strictly compared study to validate whether the above-mentioned technical
      superiorities can be translated into clinical benefits as using the DK-mini-culotte stenting
      for treatment of BL.

      So, we hypothesized that the DK-mini-culotte stenting is not only feasible technically but
      also may be superior to or at least not inferior to the DK-crush stenting in terms of
      reducing in-stent restenosis and MACE. Hereby, we now carry out a head-to-head, prospective,
      multicentre, non-inferior, randomized and controlled study to compare DK-culotte stenting
      versus DK-crush stenting in the treatment of TBL.
    

Intervention name(s): Resolute stents
Intervention type(s): Device
Intervention description(s): zotarolimus-eluting Resolute stents made by Medtronic Vascular, Inc (http://www.fda.gov/MedicalDevices/ProductsandMedicalProcedures/DeviceApprovalsandClearances/Recently-ApprovedDevices/ucm294951.htm).
Other intervention name(s): zotarolimus-eluting stents
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Treatment
Keywords: Coronary heart disease;; Percutaneous coronary intervention;; Bifurcation lesion;; Double kissing culotte technique;; clinical trial