title: Cardiac resynchronization therapy: effects on left and right ventricular ejection fraction during exercise.
abstract: In patients with heart failure and wide QRS complex, cardiac resynchronization therapy (CRT) is associated with improvement of symptoms and cardiac function. This study examined the effects of a 3-month period of CRT on left ventricular (LV) and right ventricular (RV) ejection fraction (EF) and on LV volumes, both at rest and during exercise. A CRT system was implanted in 15 patients with severe heart failure and wide QRS. Before implant and 3 months later, all patients underwent assessment of cardiac performance with equilibrium Tc(99) radionuclide angiography with imaging in the best septal left anterior oblique view. Exercise was performed on a bicycle ergometer. At 3 months, a significant improvement in New York Heart Association functional class was observed, and radionuclide angiography showed a significant decrease in LV volumes and a significant increase in LVEF at rest, as well as a significant increase in LVEF during exercise. The remodeling processes associated with CRT did not appear to include RV function, since RVEF did not improve, and changes in RVEF did not correlate with changes in LVEF, neither at rest nor during exercise.
authors.affiliation: Institute of Cardiology, University of Bologna. Bologna, Italy. cardio1@med.unibo.it
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Boriani
authors.forename: Francesco
authors.initials: F
authors.lastname: Fallani
authors.forename: Cristian
authors.initials: C
authors.lastname: Martignani
authors.forename: Mauro
authors.initials: M
authors.lastname: Biffi
authors.forename: Davide
authors.initials: D
authors.lastname: Saporito
authors.forename: Cristiano
authors.initials: C
authors.lastname: Greco
authors.forename: Matteo
authors.initials: M
authors.lastname: Ziacchi
authors.forename: Maurizio
authors.initials: M
authors.lastname: Levorato
authors.forename: Giulia
authors.initials: G
authors.lastname: Pontone
authors.forename: Cinzia
authors.initials: C
authors.lastname: Valzania
authors.forename: Igor
authors.initials: I
authors.lastname: Diemberger
authors.forename: Roberto
authors.initials: R
authors.lastname: Franchi
authors.forename: Angelo
authors.initials: A
authors.lastname: Branzi
mesh_terms: D002304:Cardiac Pacing, Artificial; D005080:Exercise Test; D005260:Female; D006333:Heart Failure / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015635:Radionuclide Ventriculography; D013318:Stroke Volume