The QRS complex, during tachycardia could be in morphology of narrow, left bundle branch block (LBBB) and right bundle branch block(RBBB) with VA dissociation.

心动过速可呈窄QRS图形、左束支传导阻滞（LBBB）图形及右束支传导阻滞（RBBB）图形。

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Conclusions the IVF with RBBB and st segment elevation is a distinct syndrome, and the mutations in the cardiac sodium channel gene SCN 5 a are associated with IVF.

结论我们的工作显示了伴有rbbb和ST段抬高的IVF是一种明显的综合征，并且心脏钠通道基因scn 5 A与IVF的发生密切相关。

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