Ammirati F, Colivicchi F, Toscano S, Pandozi C, Laudadio M T, De Seta F, Santini M
Department of Heart Disease, San Filippo Neri Hospital, Rome, Italy.
Pacing Clin Electrophysiol. 1998 Nov;21(11 Pt 2):2178-81. doi: 10.1111/j.1540-8159.1998.tb01148.x.
The effectiveness of cardiac pacing in preventing vasovagal syncope remains controversial. However, DDI pacing with rate hysteresis has been reported to prevent the recurrence of cardioinhibitory vasovagal syncope in up to 35% of affected subjects and to reduce the overall incidence of syncopal episodes in the others. Recently, DDD pacing with a new promising rate drop response function (Medtronic Thera-I model 7960) has become available in clinical practice.
The aim of the present open trial was to test the effectiveness of this new pacing modality in patients with cardioinhibitory vasovagal syncope.
The study population included 20 patients (12 males and 8 females; mean age 61.1 +/- 14 yrs) with recurrent syncope (mean number of prior episode = 6.8, range 5-11) and cardioinhibitory responses during two head-up tilt tests: the first diagnostic and the second during drug therapy with either beta-blockade or etilephrine. The study patients were randomized to receive either DDI pacing with rate hysteresis (8 patients) or DDD pacing with rate drop response function (11 patients). The head-up tilt test performed 1 month after pacemaker implantation was positive in 3 of 12 patients (25%) with DDD pacing with rate drop response function and in 5 of 8 patients (62.5%) with DDI pacing with rate hysteresis. The mean duration of follow-up was 17.7 +/- 7.4 months. During follow-up no patients with a DDD pacemaker with rate drop response function had syncope, while 3 of 8 patients with a DDI pacemaker with rate hysteresis had recurrence of syncope (P < 0.05).
These data suggest that DDD pacing with rate drop response function is effective in cardioinhibitory vasovagal syncope and may be preferable to DDI pacing with rate hysteresis.
心脏起搏预防血管迷走性晕厥的有效性仍存在争议。然而，据报道，具有频率滞后功能的DDI起搏可预防高达35%的心脏抑制性血管迷走性晕厥患者复发，并降低其他患者晕厥发作的总体发生率。最近，一种具有新的、前景良好的频率下降反应功能的DDD起搏（美敦力Thera-I 7960型）已应用于临床实践。
本开放性试验的目的是测试这种新的起搏方式对心脏抑制性血管迷走性晕厥患者的有效性。
研究对象包括20例患者（12例男性，8例女性；平均年龄61.1±14岁），这些患者反复晕厥（既往发作次数平均为6.8次，范围5 - 11次），且在两次头高位倾斜试验中出现心脏抑制反应：第一次为诊断性试验，第二次在使用β受体阻滞剂或依替福林药物治疗期间进行。研究患者被随机分为接受具有频率滞后功能的DDI起搏（8例患者）或具有频率下降反应功能的DDD起搏（11例患者）。在起搏器植入后1个月进行的头高位倾斜试验中，11例接受具有频率下降反应功能的DDD起搏的患者中有3例（25%）试验结果为阳性，8例接受具有频率滞后功能的DDI起搏的患者中有5例（62.5%）试验结果为阳性。平均随访时间为17.7±7.4个月。在随访期间，接受具有频率下降反应功能的DDD起搏器的患者无晕厥发生，而接受具有频率滞后功能的DDI起搏器的8例患者中有3例晕厥复发（P<0.05）。
这些数据表明，具有频率下降反应功能的DDD起搏对心脏抑制性血管迷走性晕厥有效，可能优于具有频率滞后功能的DDI起搏。
