Department of Clinical Examination and Diagnosis, Oita University School of Medicine, Yufu City, Oita, Japan.
Heart Rhythm. 2012 May;9(5):782-8. doi: 10.1016/j.hrthm.2011.12.022. Epub 2011 Dec 30.
The false tendons (FTs) are fibromuscular bands that transverse the left ventricular cavity and often contain conduction tissue, suggesting that FTs may contribute to the occurrence of ventricular arrhythmias. The presence of J waves is associated with vulnerability to ventricular arrhythmias; however, the mechanisms underlying the manifestation of J waves remain to be elucidated.
To investigate the electrocardiographic characteristics, including the presence of J waves, in patients with FTs.
We studied 44 patients with distinct FTs detected by echocardiography (FT group) and 88 age- and sex-matched healthy subjects without FTs (control group). The PQ, QRS, JT, QT, corrected JT, and corrected QT intervals were automatically measured on surface 12-lead electrocardiograms, and the presence or absence of J waves was also determined. J waves were defined as terminal QRS notching or slurring. FTs were classified according to their points of attachment as type 1 (longitudinal, 52%), type 2 (diagonal, 25%), type 3 (transverse, 16%), and type 4 (weblike, 7%).
QRS and corrected QT intervals were significantly longer in the FT group than in the control group (P <.005 and P <.05, respectively). The incidence of J waves was significantly higher in the FT group (64%) than in the control group (19%) (P <.0001). J waves were more prevalent in type 1 (78%) and type 2 (73%) than in type 3 (14%) and 4 FTs (33%) (P <0.05) and in patients with thick FTs (≥ 2 mm) than with thinner FTs (<2 mm) (71% vs 33%; P <.05). The J-wave location differed according to the FT type.
Our results suggest that FTs may carry a certain role to the genesis of J waves.
假腱索（FTs）是横过左心室腔的纤维肌肉带，通常包含传导组织，这表明 FTs 可能导致室性心律失常的发生。J 波的存在与室性心律失常的易感性相关；然而，J 波表现的机制仍有待阐明。
研究超声心动图检测到的 FTs 患者的心电图特征，包括 J 波的存在。
我们研究了 44 例经超声心动图明确诊断为 FTs 的患者（FT 组）和 88 例年龄和性别匹配的无 FTs 的健康对照者（对照组）。自动测量体表 12 导联心电图的 PQ、QRS、JT、QT、校正 JT 和校正 QT 间期，并确定 J 波的存在与否。J 波定义为终末 QRS 切迹或模糊。FTs 根据其附着点分为 4 型：1 型（纵向，52%）、2 型（对角，25%）、3 型（横向，16%）和 4 型（网状，7%）。
FT 组的 QRS 和校正 QT 间期明显长于对照组（P <.005 和 P <.05）。FT 组 J 波的发生率（64%）明显高于对照组（19%）（P <.0001）。1 型（78%）和 2 型（73%）FT 比 3 型（14%）和 4 型 FT（33%）更常见 J 波（P <0.05），厚 FTs（≥2mm）比薄 FTs（<2mm）更常见 J 波（71%比 33%）（P <.05）。J 波的位置与 FT 类型有关。
我们的结果表明，FTs 可能在 J 波的发生中起一定作用。
