Bellocci F, Fenici R, Loperfido F, Santarelli P, Zecchi P
G Ital Cardiol. 1977;7(7):691-705.
His Bundle Electrogram (HBE) was recorded in 20 patients with Mobitz type II block. All patients were clinically evaluated and a history of syncope was carefully investigated. These patients were prospectively followed (mean follow up: 20,4 months). ECG showed LBBB in 9 patients, RBBB + LAHI in 6, RBBB + LPH in 3, LAH in 1, left axis deviation in 1. In all patients HBE revealed prolungation of H-Q interval and localization of block within the His-Purkinje system (within H in 4) distal to H in 16. In 9 patients intermittent complete heart block localized within the H-P system was documented during HBE recording. 15 patients (75%) experienced syncopal attacks. All patients underwent implantation of permanent demand pace-maker, without further episodes of syncope. Since the site of block is the most important determinant of prognosis, in all patients with Mobitz type II block, whether or not symptoms are present, prophylactic implantation of pace-maker is indicated, because high incidence of progression to complete heart block, with potential risk of Adams-Stokes syndrome and sudden death.
对20例莫氏Ⅱ型阻滞患者记录了希氏束电图（HBE）。所有患者均进行了临床评估，并仔细调查了晕厥病史。对这些患者进行了前瞻性随访（平均随访时间：20.4个月）。心电图显示9例患者为左束支传导阻滞（LBBB），6例为右束支传导阻滞+左前分支阻滞（RBBB + LAHI），3例为右束支传导阻滞+左后分支阻滞（RBBB + LPH），1例为左前分支阻滞（LAH），1例为电轴左偏。所有患者的希氏束电图均显示H-Q间期延长，阻滞位于希氏-浦肯野系统内（4例在希氏束内，16例在希氏束远端）。9例患者在希氏束电图记录期间记录到希氏-浦肯野系统内间歇性完全性心脏阻滞。15例患者（75%）发生了晕厥发作。所有患者均植入了按需型永久性起搏器，此后未再发生晕厥。由于阻滞部位是预后的最重要决定因素，因此对于所有莫氏Ⅱ型阻滞患者，无论有无症状，均建议预防性植入起搏器，因为进展为完全性心脏阻滞的发生率较高，存在发生阿-斯综合征和猝死的潜在风险。
