Different impact of long-detection interval and anti-tachycardia pacing in reducing unnecessary shocks: data from the ADVANCE III trial

Abstract

AimsA long-detection interval (LDI) (30/40 intervals) has been proved to be superior to a standard-detection interval (SDI) (18/24 intervals) in terms of reducing unnecessary implantable cardioverter defibrillator (ICD) therapies. To better evaluate the different impact of LDI and anti-tachycardia pacing (ATP) on reducing painful shocks, we assessed all treated episodes in the ADVANCE III trial.Methods and resultsA total of 452 fast (200 ms < cycle length ≤ 320 ms) arrhythmic episodes were recorded: 284 in 138 patients in the SDI arm and 168 in 82 patients in the LDI arm (106/452 inappropriate detections). A total of 346 fast ventricular tachycardias (FVT) were detected in 169 patients: 208 in 105 patients with SDI and 138 in 64 patients with LDI. Setting LDI determined a significant reduction in appropriate but unnecessary therapies [208 in SDI vs. 138 in LDI; incidence rate ratio (IRR): 0.61 (95% CI 0.45–0.83), P = 0.002]. Anti-tachycardia pacing determined another 52% reduction in unnecessary shocks [208 in SDI with hypothetical shock-only programming vs. 66 in LDI with ATP; IRR: 0.37 (95% CI 0.25–0.53, P < 0.001)]. The efficacy of ATP in terminating FVT was 63% in SDI and 52% in LDI (P = 0.022). No difference in the safety profile (acceleration/degeneration and death/cardiovascular hospitalizations) was observed between the two groups.ConclusionThe combination of LDI and ATP during charging is extremely effective and significantly reduces appropriate but unnecessary therapies. The use of LDI alone yielded a 39% reduction in appropriate but unnecessary therapies; ATP on top of LDI determined another 52% reduction in unnecessary shocks. The strategy of associating ATP and LDI could be considered in the majority of ICD recipients.

Clinical parameters to optimize patient selection for subcutaneous and transvenous implantable defibrillator therapy

“…A longer cycle length of the ventricular arrhythmias, has been identified as predictors for successful ATP therapy in some prior studies . However, in this cohort, cycle length did not differ between successful and unsuccessful ATP attempts.…”

“…In one case, an inappropriate ATP delivered during AF induced a VT, which was terminated by a shock. Contemporary programming allows for longer detection times resulting in less inappropriate therapy, but exact impact is not well studied . However, one can expect a reduction in these numbers as the total number of ATP therapy episodes is reduced.…”

“…The monitor zone was programmed as >160 beats/min, the VT zone was programmed between >180 beats/min and <250 beats/min, and the VF zone was programmed at >250 beats/min. Contemporary number of intervals needed to detect were programmed, 30/40 intervals or similar delays (Supplementary Material). Two bursts of ATP were programmed in the VT zone.…”

“…In MADIT‐RIT, this incidence dropped from 20% to 4% . Regardless, ATP therapy remains valuable for this small percentage of patients as it provides a painless therapy modality to end sustained ventricular arrhythmia episodes …”

Inappropriate ICD Shocks in Pediatric and Congenital Heart Disease Patients

“…56,57 These studies had a significant impact on ICD programming strategies, and spawned a number of similar studies examining variations on lenient programming practices. Several studies have examined high rate programming, 58,59 while others have considered prolonged detection, [60][61][62][63][64][65] or a combination of these two approaches. 66,67 In general, lenient programming practices in these studies have demonstrated a decrease in the rate of appropriate and inappropriate shocks, with either a decrease in overall mortality or no difference, when compared to conventional programming practices.…”