title: Relation of response to cardiac resynchronization therapy to left ventricular reverse remodeling.
abstract: Cardiac resynchronization therapy (CRT) reverses left ventricular (LV) remodeling in patients with congestive heart failure. However, the mechanisms leading to the clinical response to CRT remain unclear. The aim of this study was to analyze whether patients who improve clinically have greater LV reverse remodeling than nonresponders after a 12-month follow-up period. The sample comprised 64 consecutive patients with heart failure, complete left bundle branch block, and LV ejection fractions (EFs) < or =35% who were treated with CRT. Doppler echocardiographic scans were taken just before and immediately after the implantation of the pacemakers and at 6- and 12-month follow-up examinations. LV diameters, volumes, and EFs were compared. Responders were defined as those patients who were alive without cardiac transplantation and with > or =10% improvement in the 6-minute walking test after 1 year of follow-up. There were no clinical differences at baseline between responders and nonresponders. At 6- and 12-month follow-up, LV dimensions decreased significantly in responders but did not change in nonresponders. Furthermore, LVEFs improved only in responders. In conclusion, patients who clinically respond to CRT have greater LV reverse remodeling than nonresponders after 6 and 12 months of follow-up. The effect of CRT on LV remodeling may explain, at least in part, the clinical benefit of this therapy.
authors.affiliation: Thorax Clinic Institute, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi i Sunyer, University of Barcelona, Spain. mstiges@clinic.ub.es
authors.forename: Bàrbara
authors.initials: B
authors.lastname: Vidal
authors.forename: Marta
authors.initials: M
authors.lastname: Sitges
authors.forename: Alba
authors.initials: A
authors.lastname: Marigliano
authors.forename: Ernesto
authors.initials: E
authors.lastname: Díaz-Infante
authors.forename: Manel
authors.initials: M
authors.lastname: Azqueta
authors.forename: David
authors.initials: D
authors.lastname: Tamborero
authors.forename: Alfonso
authors.initials: A
authors.lastname: Macías
authors.forename: Eulàlia
authors.initials: E
authors.lastname: Roig
authors.forename: Josep
authors.initials: J
authors.lastname: Brugada
authors.forename: Carles
authors.initials: C
authors.lastname: Paré
authors.forename: Lluís
authors.initials: L
authors.lastname: Mont
mesh_terms: D000368:Aged; D002304:Cardiac Pacing, Artificial; D015150:Echocardiography, Doppler; D005080:Exercise Test; D005260:Female; D006333:Heart Failure / Q000503:physiopathology* / Q000628:therapy*; D006801:Humans; D008297:Male; D011446:Prospective Studies; D011788:Quality of Life; D013318:Stroke Volume / Q000502:physiology; D011795:Surveys and Questionnaires; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging / Q000503:physiopathology*; D020257:Ventricular Remodeling / Q000502:physiology*