The Care Group, LLC, Indianapolis, Indiana, USA.
J Cardiovasc Electrophysiol. 2010 Jul;21(7):781-5. doi: 10.1111/j.1540-8167.2009.01714.x. Epub 2010 Feb 1.
Patients with left bundle branch block (LBBB) undergoing right heart catheterization can develop complete heart block (CHB) or right bundle branch block (RBBB) in response to right bundle branch (RBB) trauma. We hypothesized that LBBB patients with an initial r wave (>or=1 mm) in lead V1 have intact left to right ventricular septal (VS) activation suggesting persistent conduction over the left bundle branch. Trauma to the RBB should result in RBBB pattern rather than CHB in such patients.
Between January 2002 and February 2007, we prospectively evaluated 27 consecutive patients with LBBB developing either CHB or RBBB during right heart catheterization. The prevalence of an r wave >or=1 mm in lead V1 was determined using 118 serial LBBB electrocardiographs (ECGs) from our hospital database.
Catheter trauma to the RBB resulted in CHB in 18 patients and RBBB in 9 patients. All 6 patients with >or=1 mm r wave in V1 developed RBBB. Among these 6 patients q wave in lead I, V5, or V6 were present in 3. Four patients (3 in CHB group and 1 in RBBB group) developed spontaneous CHB during a median follow-up of 61 months. V1 q wave >or=1 mm was present in 28% of hospitalized complete LBBB patients.
An initial r wave of >or=1 mm in lead V1 suggests intact left to right VS activation and identifies LBBB patients at low risk of CHB during right heart catheterization. These preliminary findings indicate that an initial r wave of >or=1 mm in lead V1, present in approximately 28% of ECGs with classically defined LBBB, may constitute a new exclusion criterion when defining complete LBBB.
接受右心导管检查的左束支传导阻滞（LBBB）患者可能会因右束支（RBB）损伤而发生完全性心脏阻滞（CHB）或右束支传导阻滞（RBBB）。我们假设，初始 V1 导联 r 波（≥1mm）的 LBBB 患者，其左至右室间隔（VS）激活完整，提示左束支持续传导。在这些患者中，RBB 损伤应导致 RBBB 模式，而不是 CHB。
2002 年 1 月至 2007 年 2 月，我们前瞻性评估了 27 例 LBBB 患者，这些患者在右心导管检查过程中发生 CHB 或 RBBB。使用我们医院数据库中的 118 份连续 LBBB 心电图（ECG）确定 V1 导联 r 波＞=1mm 的发生率。
RBB 导管损伤导致 18 例患者发生 CHB，9 例患者发生 RBBB。所有 6 例 V1 导联 r 波＞=1mm 的患者均发生 RBBB。在这 6 例患者中，3 例患者 I 导联、V5 导联或 V6 导联存在 q 波。4 例患者（CHB 组 3 例，RBBB 组 1 例）在中位随访 61 个月时发生自发性 CHB。28%住院的完全性 LBBB 患者 V1 导联 q 波＞=1mm。
V1 导联初始 r 波＞=1mm 提示左至右 VS 激活完整，可识别右心导管检查中 CHB 风险较低的 LBBB 患者。这些初步发现表明，在大约 28%的经典定义 LBBB 的 ECG 中存在 V1 导联初始 r 波＞=1mm，可能构成定义完全性 LBBB 的新排除标准。
