A randomized study to compare ramp versus burst antitachycardia pacing therapies to treat fast ventricular tachyarrhythmias in patients with implantable cardioverter defibrillators: the PITAGORA ICD trial.
BACKGROUND
In patients with implantable cardioverter-defibrillators (ICDs), antitachycardia pacing (ATP) is highly effective in terminating fast ventricular tachycardias (FVTs) and lowers the use of high-energy shocks, without increasing the risk of arrhythmia acceleration or syncope.


RESULTS
The aim of the PITAGORA ICD trial was to randomly compare 2 ATP strategies (88% coupling interval burst versus 91% coupling interval ramp, both 8 pulses) in terms of ATP efficacy, arrhythmia acceleration, and syncope. Two hundred six ICD patients (83% male, 67+/-11 years) were enrolled. FVT episodes with cycle lengths between 240 and 320 ms were treated by 1 ATP sequence and, in the event of failure, by shocks. Over a median follow-up of 36 months, 829 spontaneous ventricular tachyarrhythmia episodes were detected in 79 patients. Episode review identified 595 episodes as true ventricular arrhythmias in 72 patients; devices classified 111 (18.7%) episodes as VF, 216 (36.3%) as FVT, and 268 (45.0%) as VT. Fifty-six patients had 214 treated FVT episodes-2 FVTs self-terminated before ATP release; 44 (79%) of these had at least 1 effective ATP intervention, and 34 (61%) were spared ICD shocks. Burst terminated 100 of 133 (75.2%) FVT episodes, whereas ramp terminated 44 of 81 (54.3%; P=0.015). Acceleration occurred in 9 of 214 (4.2%) FVT episodes treated: 6 episodes in 3 ramp patients and 3 episodes in 3 burst patients. Two patients-1 in each group-suffered 1 syncopal event associated to a nonterminated FVT episode.


CONCLUSIONS
Burst is significantly more efficacious than ramp in terminating FVT episodes. As the first therapy for FVT episodes, ATP carries a low risk of acceleration or syncopal events.
Gulizia
Michele M
MM
Garibaldi-Nesima Hospital, Catania, Italy. michele.gulizia@tin.it
Piraino
Leandro
L
Scherillo
Marino
M
Puntrello
Calogero
C
Vasco
Calogero
C
Scianaro
Maria Carmela
MC
Mascia
Franco
F
Pensabene
Orazio
O
Giglia
Salvatore
S
Chiarandà
Giacomo
G
Vaccaro
Ignazio
I
Mangiameli
Salvatore
S
Corrao
Dario
D
Santi
Elisabetta
E
Grammatico
Andrea
A
D000368:Aged; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D017147:Defibrillators, Implantable; D005260:Female; D005500:Follow-Up Studies; D006760:Hospitalization; D006801:Humans; D008297:Male; D008875:Middle Aged; D011788:Quality of Life; D013575:Syncope / Q000503:physiopathology / Q000628:therapy; D017180:Tachycardia, Ventricular / Q000503:physiopathology* / Q000628:therapy*; D016896:Treatment Outcome