Shock Reduction Using Antitachycardia Pacing for Spontaneous Rapid Ventricular Tachycardia in Patients With Coronary Artery Disease

Abstract

Background-Implantable cardioverter-defibrillators (ICDs) can terminate some ventricular tachycardias (VTs) painlessly with antitachycardia pacing (ATP). ATP has not routinely been applied for VT Ͼ188 bpm because of concerns about efficacy, risk of acceleration, and delay of definitive shock therapy. This prospective, multicenter study evaluated the efficacy of empirical ATP to terminate fast VT (FVT; Ͼ188 bpm). Methods and Results-Two hundred twenty coronary artery disease patients received ICDs for standard indications.Empirical, standardized therapy was programmed so that all FVT episodes (average cycle length [CL] 240 to 320 ms, 250 to 188 bpm) were treated with 2 ATP sequences (8-pulse burst pacing train at 88% of the FVT CL) before shock delivery. A total of 1100 episodes of spontaneous ventricular tachyarrhythmias occurred during a mean of 6.9Ϯ3.6 months of follow-up. Fifty-seven percent were classified as slow VT (CLՆ320 ms), 40% as FVT (240 msՅCLϽ320 ms), and 3% as ventricular fibrillation (CLϽ240 ms). A total of 446 FVT episodes, mean CLϭ301Ϯ24 ms, occurred in 52 patients (median 2 episodes per patient). ATP terminated 396 FVT episodes (89%), with an adjusted efficacy of 77% (95% CI 68% to 83%). VT acceleration caused by ATP occurred in 10 FVT episodes (4%). FVT arrhythmic syncope occurred on 9 occasions (2%) in 4 patients. Conclusions-FVT (CLϽ320 ms) is common in ICD patients. ATP can terminate 3 of 4 of these episodes with a low incidence of acceleration and syncope. ATP for FVT may safely reduce the morbidity of painful shocks.

2015 HRS/EHRA/APHRS/SOLAECE expert consensus statement on optimal implantable cardioverter-defibrillator programming and testing

“…This programming might improve survival [126]. Indeed, several studies have shown that ATP is effective at terminating slow and fast VT with exceedingly low rates of adverse events like syncope [93,135,[161][162][163][164][165]. The initial bias of the ICD community was to reserve ATP therapy for those patients in whom the therapy was demonstrated to be effective, usually during an electrophysiologic study.…”

“…It is not reflective of the arrhythmias experienced outside the electrophysiology laboratory for primary and secondary prevention patients with ischemic and nonischemic substrates [101,166]. Although the ideal number of ATP bursts has not been definitively determined, current data support the use of up to 2 ATP attempts, given additional attempts yield very little additional efficacy [93,135,[161][162][163][164][165]167,168]. In one study, up to 5 attempts were found to be safe [168].…”

Prospective Randomized Multicenter Trial of Empirical Antitachycardia Pacing Versus Shocks for Spontaneous Rapid Ventricular Tachycardia in Patients With Implantable Cardioverter-Defibrillators

“…ATP was equally effective in patients without coronary artery disease, a group excluded from the pilot study, PainFREE Rx. 11 The greatest predictor of ATP success in PainFREE Rx was NSVT. 11 One may infer that the device was claiming ATP success for treating nonsustained FVT episodes that were destined to terminate regardless of therapy, a reasonable conclusion given that VF plus FVT detection used 12 of 16 intervals.…”

“…11 The greatest predictor of ATP success in PainFREE Rx was NSVT. 11 One may infer that the device was claiming ATP success for treating nonsustained FVT episodes that were destined to terminate regardless of therapy, a reasonable conclusion given that VF plus FVT detection used 12 of 16 intervals. Consequently, this trial used 18 of 24 intervals for VF plus FVT detection and found that NSVT was not a predictor of ATP success.…”

“…Fast VT (FVT, 188 to 250 bpm) is typically programmed to receive painful shock therapy even though ATP might be successful. More recently, high success and low acceleration rates for FVT were demonstrated in coronary artery disease patients 10,11 but in a nonrandomized fashion, so a comparison with shocks for safety and QoL was not performed. This trial examined the efficacy, safety, and QoL associated with treatment of FVT with ATP compared with shocks in a broad ICD population.…”