摘要
Background-Successful antitachycardia pacing(ATP) terminates ventricular tachycardia(VT) up to 250 bpm without the need for painful shocks in implantable cardioverter-defibrillator(ICD) patients. Fast VT(FVT) >200 bpm is often treated by shock because of safety concerns, however. This prospective, randomized, multicenter trial compares the safety and utility of empirical ATP with shocks for FVT in a broad ICD population. Methods and Results-We randomized 634 ICD patients to 2 arms-standardized empirical ATP(n=313) or shock (n=321)-for initial therapy of spontaneous FVT. ICDs were programmed to detect FVT when 18 of 24 intervals were 188 to 250 bpm and 0 of the last 8 intervals were >250 bpm. Initial FVT therapy was ATP (8 pulses, 88%of FVT cycle length) or shock at 10 J above the defibrillation threshold. Syncope and arrhythmic symptoms were collected through patient diaries and interviews. In 11±3 months of follow-up, 431 episodes of FVT occurred in 98 patients, representing 32%of ventricular tachyarrhythmias and 76%of those that would be detected as ventricular fibrillation and shocked with traditional ICD programming. ATP was effective in 229 of 284 episodes in the ATP arm(81%, 72%adjusted). Acceleration, episode duration, syncope, and sudden death were similar between arms. Quality of life, measured with the SF-36, improved in patients with FVT in both arms but more so in the ATP arm. Conclusions-Compared with shocks, empirical ATP for FVT is highly effective, is equally safe, and improves quality of life. ATP may be the preferred FVT therapy in most ICD patients.
Background-Successful antitachycardia pacing(ATP) terminates ventricular tachycardia(VT) up to 250 bpm without the need for painful shocks in implantable cardioverter-defibrillator(ICD) patients. Fast VT(FVT) >200 bpm is often treated by shock because of safety concerns, however. This prospective, randomized, multicenter trial compares the safety and utility of empirical ATP with shocks for FVT in a broad ICD population. Methods and Results-We randomized 634 ICD patients to 2 arms-standardized empirical ATP(n=313) or shock (n=321)-for initial therapy of spontaneous FVT. ICDs were programmed to detect FVT when 18 of 24 intervals were 188 to 250 bpm and 0 of the last 8 intervals were >250 bpm. Initial FVT therapy was ATP (8 pulses, 88%of FVT cycle length) or shock at 10 J above the defibrillation threshold. Syncope and arrhythmic symptoms were collected through patient diaries and interviews. In 11±3 months of follow-up, 431 episodes of FVT occurred in 98 patients, representing 32%of ventricular tachyarrhythmias and 76%of those that would be detected as ventricular fibrillation and shocked with traditional ICD programming. ATP was effective in 229 of 284 episodes in the ATP arm(81%, 72%adjusted). Acceleration, episode duration, syncope, and sudden death were similar between arms. Quality of life, measured with the SF-36, improved in patients with FVT in both arms but more so in the ATP arm. Conclusions-Compared with shocks, empirical ATP for FVT is highly effective, is equally safe, and improves quality of life. ATP may be the preferred FVT therapy in most ICD patients.
