title: Avoiding non-responders to cardiac resynchronization therapy: a practical guide.
abstract: Over two decades after the introduction of cardiac resynchronization therapy (CRT) into clinical practice, ∼30% of candidates continue to fail to respond to this highly effective treatment of drug-refractory heart failure (HF). Since the causes of this non-response (NR) are multifactorial, it will require multidisciplinary efforts to overcome. Progress has, thus far, been slowed by several factors, ranging from a lack of consensus regarding the definition of NR and technological limitations to the delivery of therapy. We critically review the various endpoints that have been used in landmark clinical trials of CRT, and the variability in response rates that has been observed as a result of these different investigational designs, different sample populations enrolled and different means of therapy delivered, including new means of multisite and left ventricular endocardial simulation. Precise recommendations are offered regarding the optimal device programming, use of telemonitoring and optimization of management of HF. Potentially reversible causes of NR to CRT are reviewed, with emphasis on loss of biventricular stimulation due to competing arrhythmias. The prevention of NR to CRT is essential to improve the overall performance of this treatment and lower its risk-benefit ratio. These objectives require collaborative efforts by the HF team, the electrophysiologists and the cardiac imaging experts.
authors.affiliation: School of medicine, Rennes 1 University, Rennes, France.|LTSI INSERM U1099, Rennes, France.
authors.forename: Claude
authors.initials: C
authors.lastname: Daubert
authors.affiliation: Cardiology and vascular diseases Division, Rennes University Hospital, Rennes, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Behar
authors.affiliation: School of medicine, Rennes 1 University, Rennes, France.|LTSI INSERM U1099, Rennes, France.|Cardiology and vascular diseases Division, Rennes University Hospital, Rennes, France.
authors.forename: Raphaël P
authors.initials: RP
authors.lastname: Martins
authors.affiliation: School of medicine, Rennes 1 University, Rennes, France.|LTSI INSERM U1099, Rennes, France.|Cardiology and vascular diseases Division, Rennes University Hospital, Rennes, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Mabo
authors.affiliation: School of medicine, Rennes 1 University, Rennes, France.|LTSI INSERM U1099, Rennes, France.|Cardiology and vascular diseases Division, Rennes University Hospital, Rennes, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Leclercq
mesh_terms: D002304:Cardiac Pacing, Artificial / Q000379:methods; D058406:Cardiac Resynchronization Therapy; D002986:Clinical Trials as Topic; D032921:Consensus; D004452:Echocardiography; D019317:Evidence-Based Medicine; D006333:Heart Failure / Q000628:therapy*; D006801:Humans; D018579:Patient Selection; D017410:Practice Guidelines as Topic; D011788:Quality of Life; D017211:Treatment Failure; D018487:Ventricular Dysfunction, Left / Q000628:therapy; D020257:Ventricular Remodeling / Q000502:physiology
keywords: Cardiac resynchronization therapy; Heart failure; Left bundle branch block; Therapeutic response; Ventricular remodelling