title: Ventricular antitachycardia pacing therapy in patients with heart failure implanted with a cardiac resynchronization therapy defibrillator device: Efficacy, safety, and impact on mortality.
abstract: BACKGROUND
  Cardiac resynchronization therapy defibrillator can terminate ventricular tachycardia (VT) and fast VT (FVT) via antitachycardia pacing (ATP).
  
  
  OBJECTIVE
  We evaluated efficacy and safety of ATP, whether ATP induces ventricular arrhythmias after inappropriate ATP or atrial fibrillation (AF) after appropriate ATP, and whether ATP is associated with mortality.
  
  
  METHODS
  A total of 1404 patients with a cardiac resynchronization therapy defibrillator were followed in a prospective multicenter observational research. All-cause mortality rates were estimated in patient subgroups in order to uncouple the trigger (VT/FVT or other rhythms causing inappropriate detections) from ATP therapy.
  
  
  RESULTS
  Over a median follow-up of 31 months, 2938 VT/FVT episodes were treated with ATP in 360 patients. The adjusted ATP success rate was 63% (95% confidence interval [CI] 57%-69%) on FVTs and 68% (95% CI 62%-74%) on VTs. Acceleration occurred in 55 (1.87%) and syncope in 4 (0.14%) of all ATP-treated episodes. In 14 true VT/FVT episodes in 5 patients, AF followed ATP therapy. In 4 episodes in 2 patients, VT followed ATP inappropriately applied during AF. Death rate per 100 patient-years was 5.6 (95% CI 4.3-7.5) in patients with appropriate ATP and 1.5 (95% CI 0.4-6.1) in patients with inappropriate ATP (P = .045).
  
  
  CONCLUSIONS
  ATP was effective in terminating VT/FVT episodes and displayed a good safety profile. ATP therapies by themselves did not increase death risk; prognosis was indeed better in patients without arrhythmic episodes, even if they received inappropriate ATP, than in patients with ATP on VT/FVT episodes. Adverse outcomes observed in patients receiving implantable cardioverter-defibrillator therapies are probably related to the arrhythmia itself, a marker of disease progression, rather than to adverse effects of ATP.
authors.affiliation: Fondazione Policlinico S. Matteo IRCCS, Pavia, Italy; Ospedale Maggiore, Crema, Italy. Electronic address: maurizio.landolina02@gmail.com.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Landolina
authors.affiliation: Ospedale Niguarda Ca' Granda, Milan, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Lunati
authors.affiliation: Università di Bologna e Azienda Ospedaliera S. Orsola-Malpighi, Bologna, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Boriani
authors.affiliation: Ospedale San Filippo Neri, Rome, Italy.
authors.forename: Renato
authors.initials: R
authors.lastname: Pietro Ricci
authors.affiliation: Ospedale S. Maria della Misericordia, Udine, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Proclemer
authors.affiliation: Ospedale S. Maria della Misericordia, Udine, Italy.
authors.forename: Domenico
authors.initials: D
authors.lastname: Facchin
authors.affiliation: Fondazione Policlinico S. Matteo IRCCS, Pavia, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Rordorf
authors.affiliation: Ospedale Borgo Trento, Verona, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Morani
authors.affiliation: Ospedale Santa Maria del Carmine Rovereto, Italy.
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Maines
authors.affiliation: Ospedale dell'Angelo, Mestre, Italy.
authors.forename: Gianni
authors.initials: G
authors.lastname: Gasparini
authors.affiliation: Ospedale Sacro Cuore Don Calabria, Negrar, Italy.
authors.forename: Giulio
authors.initials: G
authors.lastname: Molon
authors.affiliation: Ospedale P. Cosma, Camposampiero, Italy.
authors.forename: Pietro
authors.initials: P
authors.lastname: Turrini
authors.affiliation: IRCCS Istituto Clinico Humanitas, Rozzano, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Gasparini
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000209:etiology / Q000517:prevention & control; D058406:Cardiac Resynchronization Therapy / Q000009:adverse effects / Q000379:methods; D058409:Cardiac Resynchronization Therapy Devices / Q000009:adverse effects*; D018450:Disease Progression; D019544:Equipment Failure Analysis / Q000379:methods; D005260:Female; D006333:Heart Failure / Q000150:complications / Q000175:diagnosis / Q000401:mortality / Q000628:therapy; D006801:Humans; D007558:Italy; D008297:Male; D008875:Middle Aged; D009026:Mortality; D011379:Prognosis; D011446:Prospective Studies; D017180:Tachycardia, Ventricular / Q000209:etiology / Q000401:mortality / Q000517:prevention & control; D016896:Treatment Outcome
keywords: Antitachycardia pacing therapy (ATP); Death; Implantable cardioverter-defibrillators; Safety