Transcatheter Aortic Valve Implantation Without Predilation
Condition: Aortic Stenosis; Left Ventricular Function Systolic Dysfunction; High-risk Patients; Transcatheter Aortic Valve Implantation
MeSH terms: Aortic Valve Stenosis
Study type: Interventional

Summary: 
      The purpose of this study is to demonstrate that the avoidance of balloon valvuloplasty for
      predilation of the native aortic valve is associated with a reduction of the composite
      primary endpoint in TAVI patients with severely impaired left-ventricular ejection fraction
      (LVEF ≤35%).
    

Detailed description: 
      Transcatheter aortic valve implantation (TAVI) has evolved as an alternative to surgical
      aortic valve replacement (SAVR) with now more than 50,000 implantations in patients with
      symptomatic severe aortic stenosis, who were considered to be at very high or prohibitive
      operative risk. Before deployment of transcatheter heart valves (THV), current medical
      practice requires right-ventricular rapid burst pacing (>180 bpm) with induction of a
      functional cardiac arrest for up to 30 seconds for balloon aortic valvuloplasty (BAV). This
      step is thought to be necessary to predilate the native aortic valve and to facilitate an
      accurate positioning of the THV. However, BAV has been shown to have numerous detrimental
      effects: i) the functional cardiac arrest induced by rapid pacing for BAV leads to transient
      coronary, cerebral, and renal ischemia. ii) In patients with impaired left ventricular
      ejection fraction, prolonged cardiac depression after rapid pacing is observed and may result
      in hemodynamic failure and systemic inflammatory response syndrome (SIRS), which are both
      associated with a high peri-procedural mortality. iii) BAV has been identified as a major
      source of embolization of thrombotic and valvular material and increases the risk for
      coronary obstruction with subsequent myocardial infarction and stroke. iv) the local trauma
      in the left-ventricular outflow tract caused by BAV contributes to conduction disturbances
      with the need for permanent pacemaker implantation after TAVI.

      A non-randomized pilot study by Grube et al. (JACC Interventions 2011) has recently shown
      that TAVI without BAV is feasible and safe, since self-expanding THV are able to "dilate" the
      stenosed aortic valve through the radial forces of the self-expanding nitinol frame, in which
      the prosthesis is mounted. According to the mentioned study, omitting BAV allows the delivery
      of the THV in a controlled fashion without hemodynamic compromise of the patient.

      Patients with LVEF≤35% will be randomized (like the flip of a coin) to TAVI without BAV
      (experimental group) or TAVI with BAV for predilation (control group).
    

Intervention name(s): TAVI without BAV; TAVI standard procedure
Intervention type(s): Procedure; Procedure
Intervention description(s): Avoidance of balloon valvuloplasty (BAV) of the native aortic valve before valve deployment; TAVI standard procedure including BAV before valve deployment
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: Aortic stenosis; Transcatheter aortic valve implantation; TAVI; Predilation; Balloon valvuloplasty; BAV; CoreValve