Levy M N, Kerin N, Eisenstein I
J Electrocardiol. 1977 Jul;10(3):225-32. doi: 10.1016/s0022-0736(77)80063-0.
A subvariant of the "even variant" of concealed bigeminy was studied in two patients. The typical pattern consisted of two types of sequences of conducted sinus beats between extrasystoles. One pattern was bigeminal, i.e., alternating sinus beats and extrasystoles. Between bigeminal sequences were intervals in which there were more than one conducted sinus beat between extrasystoles. In such longer sequences, the numbers of sinus beats were almost invariably even. In the bigeminal sequences, the coupling intervals progressively diminished for each successive extrasystole in the sequence. The proposed explanation for the subvariant was based on a reentry loop in which there were three sites of block: proximal, intermediate, and distal. Block was postulated to take place at the proximal site after those extrasystoles with the shortest coupling intervals, at the intermediate site after odd-numbered conducted sinus beats in the non-bigeminal sequences, and at the distal site ("concealment") after the even-numbered sinus beats in these longer sequences.
对两名患者的隐匿性二联律“偶数型变异”的一个亚型进行了研究。典型模式由早搏之间传导的窦性搏动的两种序列类型组成。一种模式是二联律，即窦性搏动和早搏交替出现。在二联律序列之间存在一些间期，其中早搏之间有一个以上传导的窦性搏动。在这样较长的序列中，窦性搏动的数量几乎总是偶数。在二联律序列中，该序列中每个连续早搏的配对间期逐渐缩短。对该亚型的推测解释基于一个折返环，其中有三个阻滞部位：近端、中间和远端。推测在配对间期最短的早搏之后，近端部位发生阻滞；在非二联律序列中的奇数传导窦性搏动之后，中间部位发生阻滞；在这些较长序列中的偶数窦性搏动之后，远端部位发生阻滞（“隐匿”）。
