Efficacy of a tool combining guide-wire and stylet for the left ventricular lead positioning.

AIMS: The left ventricular (LV) lead for cardiac resynchronization therapy (CRT) is usually positioned in the coronary sinus via a stylet-guided or an 'over-the-wire' approach. Recently, a new tool has been developed, the Medtronic Attain Hybrid, that combines guide-wire and stylet features. We assessed its safety and efficacy in comparison with standard tools currently used in clinical practice. METHODS AND RESULTS: Patients undergoing standard CRT device implantation were enrolled in seven Italian centres. In the preliminary phase of the study (Phase I), data were collected during implantation procedures performed with standard tools (three patients per centre). Subsequently, the Attain Hybrid was made available in the centres and data were collected for all consecutive patients undergoing implantation during the following year. A learning phase was considered (Phase II), and the last three patients per centre (Phase III) were used for comparison with Phase I. One hundred and seventeen patients were enrolled: 21 patients in Phase I, 75 in Phase II, and 21 in Phase III. Rates of successful implantation were similar in Phases I and III (95 vs. 100%, P=1.000). The pre-defined target vein was reached in 15 (71%) patients in Phase I and in 21 (100%) patients in Phase III (P=0.021). In 10 (48%) procedures during Phase I, LV lead positioning necessitated switching from guide-wire to stylet; this proportion decreased during Phase III (14%, P=0.043). Mean LV positioning time was 16±7 min in Phase I and 11±6 min in Phase III (P=0.040). No adverse events or lead-related complications were detected on implantation or during a follow-up of 6±4 months. CONCLUSION: The Attain Hybrid is safe and effective. It significantly improves target vein accessibility and reduces procedural time in comparison with conventional tools.

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. METHODS AND 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.