这一基质可以是旁道（可引起房室折返性心动过速或预激综合征）；心房或心室的异常兴奋灶（房性异位性心动过速或室性心动过速）；心房或心室的一个瘢痕，形成折返性心动过速环路的一个成分（房扑或室性心动过速）；或房室结双径路（房室结折返性心过动速）。
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