Atrioventricular junction ablation in patients with atrial fibrillation treated with cardiac resynchronization therapy: positive impact on ventricular arrhythmias, implantable cardioverter-defibrillator therapies and hospitalizations.

AIMS: We sought to determine whether atrioventricular junction ablation (AVJA) in patients with cardiac resynchronization therapy (CRT) implantable cardioverter-defibrillator (ICD) and with permanent atrial fibrillation (AF) has a positive impact on ICD shocks and hospitalizations compared with rate-slowing drugs. METHODS AND RESULTS: This is a pooled analysis of data from 179 international centres participating in two randomized trials and one prospective observational research. The co-primary endpoints were all-cause ICD shocks and all-cause hospitalizations. Out of 3358 CRT-ICD patients (2720 male, 66.6 years), 2694 (80%) were in sinus rhythm (SR) and 664 (20%) had permanent AF-262 (8%) treated with AVJA (AF + AVJA) and 402 (12%) treated with rate-slowing drugs (AF + Drugs). Median follow-up was 18 months. The mean (95% confidence intervals) annual rate of all-cause ICD shocks per 100 patient years was 8.0 (5.3-11.9) in AF + AVJA, 43.6 (37.7-50.4) in AF + Drugs, and 34.4 (32.5-36.5) in SR patients, resulting in incidence rate ratio (IRR) reductions of 0.18 (0.10-0.32) for AF + AVJA vs. AF + Drugs (P < 0.001) and 0.48 (0.35-0.66) for AF + AVJA vs. SR (P < 0.001). These reductions were driven by significant reductions in both appropriate ICD shocks [IRR 0.23 (0.13-0.40), P < 0.001, vs. AF + Drugs] and inappropriate ICD shocks [IRR 0.09 (0.04-0.21), P < 0.001, vs. AF + Drugs]. Annual rate of all-cause hospitalizations was significantly lower in AF + AVJA vs. AF + Drugs [IRR 0.57 (0.41-0.79), P < 0.001] and SR [IRR 0.85 (073-0.98), P = 0.027]. CONCLUSION: In AF patients treated with CRT, AVJA results in a lower incidence and burden of all-cause, appropriate and inappropriate ICD shocks, as well as to fewer all-cause and heart failure hospitalizations. CLINICAL TRIAL REGISTRATION: NCT00147290, NCT00617175, NCT01007474.

Long Detection Programming in Single-Chamber Defibrillators Reduces Unnecessary Therapies and Mortality: The ADVANCE III Trial.

OBJECTIVES: This study sought to evaluate the effects of programming a long detection in single-chamber (VVI) implantable cardioverter-defibrillators (ICDs) in the multicenter prospective ADVANCE III (Avoid DeliVering TherApies for Non-sustained Arrhythmias in ICD PatiEnts III) trial. BACKGROUND: Programming strategies may reduce unnecessary ICD shocks and their adverse effects but to date have been described only for dual-chamber ICDs. METHODS: A total of 545 subjects (85% male; atrial fibrillation 25%, left ventricular ejection fraction 31%, ischemic etiology 68%, secondary prevention indications 32%) receiving a VVI ICD were randomized to long detection (30 of 40 intervals) or standard programming (18 of 24 intervals) based on device type, atrial fibrillation history, and indication. In both arms, antitachycardia pacing (ATP) therapy during charging was programmed for episodes with cycle length 320 to 200 ms and shock only for cycle length <200 ms. Wavelet and stability functions enabled. Therapies delivered were compared using a negative binomial regression model. RESULTS: A total of 267 patients were randomized to long detection and 278 to the control group. Median follow-up was 12 months. One hundred twelve therapies (shocks and ATP) occurred in the long detection arm versus 257 in the control arm, for a 48% reduction with 30 of 40 intervals (95% confidence interval [CI]: 0.36 to 0.76; p = 0.002). In the long detection arm, overall shocks were reduced by 40% compared to the control arm (48 vs. 24; 95% CI: 0.38 to 0.94; p = 0.026) and appropriate shocks by 51% (34 vs. 74; 95% CI: 0.26 to 0.94; p = 0.033). Syncopal events did not differ between arms, but survival improved in the long detection arm. CONCLUSIONS: Among patients implanted with a VVI ICD, programming with the long detection interval significantly reduced appropriate therapies, shocks, and all-cause mortality. (Avoid DeliVering TherApies for Non-sustained Arrhythmias in ICD PatiEnts III [ADVANCEIII]; NCT00617175).

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

AIMS: A 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 RESULTS: A 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. CONCLUSION: The 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.

Efficacy of long detection interval implantable cardioverter-defibrillator settings in secondary prevention population: data from the Avoid Delivering Therapies for Nonsustained Arrhythmias in ICD Patients III (ADVANCE III) trial.

BACKGROUND: Three trials demonstrated recently that a long detection window reduces implantable cardioverter-defibrillator (ICD) therapy in primary prevention patients. Avoid Delivering Therapies for Nonsustained Arrhythmias in ICD Patients III (ADVANCE III) was the only trial that enrolled both primary and secondary prevention patients. METHODS AND RESULTS: Of the 1902 patients enrolled in the ADVANCE III trial, 477 received a defibrillator for secondary prevention; 248 patients were randomly assigned to a long detection setting (30 of 40 intervals) and 229 to the nominal setting (18 of 24 intervals) for ventricular arrhythmias with cycle length ≤ 320 ms. Eight-five percent of patients were men, with a mean age of 65 ± 12 years, a previous history of ventricular fibrillation in 37% of the cases, and a mean ejection fraction of 38 ± 13%. The ICD device mix was 37% single chamber, 47% dual chamber, and 16% triple chamber. Over a median period of 12 months, the long detection period was associated with a 25% reduction in the number of overall therapies (115.6 versus 86.8 per 100 patient-years; incidence rate ratio, 0.75; 95% confidence interval, 0.61-0.93; P=0.008) and a 34% reduction in the number of shocks (rate per 100 patient-years, 51.2 versus 38.1; incidence rate ratio, 0.66; 95% confidence interval, 0.48-0.89; P=0.007). Appropriate therapies (89.7 versus 67.7; incidence rate ratio, 0.77; 95% confidence interval, 0.60-0.97; P=0.029) and appropriate shocks (37.1 versus 28.1; incidence rate ratio, 0.64; 95% confidence interval, 0.45-0.93; P=0.018) were also reduced. CONCLUSIONS: ADVANCE III is the first randomized trial to assess a long detection window setting in ICDs in both primary and secondary prevention populations and demonstrates a reduction of overall therapies and shocks in the subgroup of secondary prevention patients. These data suggest that even the secondary prevention population may benefit from programming that combines a long detection period with antitachycardia pacing during charging. CLINICAL TRIAL REGISTRATION URL: http://www/clinicaltrials.gov. Unique identifier: NCT00617175.

Effect of long-detection interval vs standard-detection interval for implantable cardioverter-defibrillators on antitachycardia pacing and shock delivery: the ADVANCE III randomized clinical trial.

IMPORTANCE: Using more intervals to detect ventricular tachyarrhythmias has been associated with reducing unnecessary implantable cardioverter-defibrillator (ICD) therapies. OBJECTIVE: To determine whether using 30 of 40 intervals to detect ventricular arrhythmias (VT) (long detection) during spontaneous fast VT episodes reduces antitachycardia pacing (ATP) and shock delivery more than 18 of 24 intervals (standard detection). DESIGN, SETTING, AND PARTICIPANTS: Randomized, single-blind, parallel-group trial that enrolled 1902 primary and secondary prevention patients (mean [SD] age, 65 [11] years; 84% men; 75% primary prevention ICD) with ischemic and nonischemic etiology undergoing first ICD implant at 1 of 94 international centers (March 2008-December 2010). INTERVENTIONS: Patients were randomized 1:1 to programming with long- (n = 948) or standard-detection (n = 954) intervals. MAIN OUTCOMES AND MEASURES: Total number of ATPs and shocks delivered for all episodes (primary outcomes) and inappropriate shocks, mortality, and syncopal rate (secondary outcomes). RESULTS: During a median follow-up of 12 months (interquartile range, 11-13), long-detection group had 346 delivered therapies (42 therapies per 100 person-years, 95% CI, 38-47) vs 557 in the standard-detection group (67 therapies per 100 person-years [95% CI, 62-73]; incident rate ratio [IRR], 0.63 [95% CI, 0.51-0.78]; P < .001). The long- vs the standard-detection group experienced 23 ATPs per 100 person-years (95% CI, 20-27) vs 37 ATPs per 100 person-years (95% CI, 33-41; IRR, 0.58 [95% CI, 0.47-0.72]; P < .001); 19 shocks per 100 person-years (95% CI, 16-22) vs 30 shocks per 100 person-years (95% CI, 26-34; IRR, 0.77 [95% CI, 0.59-1.01]; P = .06), with a significant difference in the probability of therapy occurrence (P < .001); and a reduction in first occurrence of inappropriate shock (5.1 per 100 patient-years [95% CI, 3.7-6.9] vs 11.6 [95% CI, 9.4-14.1]; IRR, 0.55 [95% CI, 0.36-0.85]; P = .008). Mortality (5.5 [95% CI, 4.0-7.2] vs 6.3 [95% CI, 4.8-8.2] per 100 patient-years; HR, 0.87; P = .50) and arrhythmic syncope rates (3.1 [95% CI, 2.6-4.6] vs 1.9 [95% CI, 1.1-3.1] per 100 patient-years; IRR, 1.60 [95% CI, 0.76-3.41]; P = .22) did not differ significantly between groups. CONCLUSIONS AND RELEVANCE: Among patients receiving an ICD, the use of a long- vs standard-detection interval resulted in a lower rate of ATP and shocks, and inappropriate shocks. This programming strategy may be an appropriate alternative. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00617175.